№，ï****************~~~~ze：zzzzzzzzzzzzzzz-z=aza， ||||||||||||| sº º ºsº & ERIS-PENINS gº º º ſº --------> |-> S.J.AGENUINºyº, JºJº Rºº É É º 2. - º & sº Eºº e º sº. --> <- § Rilliºttluntºuri, Engineering Library —r [= Lt-ºf | 9 | ,” *...* \. | & C II* Internat. Congress of Refrigeration, Vienna I9 Io ENGLISH EDITION of the Reports and Proceedings Vienna 1911. – Edited by the ,General Commissariat". Printed by J. Weiner, furnisher of the I. R. Court . Vienna VIII. DEDICATED TO THE ENGLISH SPEAKING MEMBERS. e-wººgºs s * II* International Congress of Refrigeration, { Vienna 1910. Protector: H. J. R. H. Archduke LEOPOLD SALVATOR. Honorary Presidents: . His Excellency Baron Dr. Richard von Bienerth, I. R. Ministerpräsident X) X (Prime-Minister); Baron Guido von Haerdtl, I. R. Minister des Innern (Home- Minister); Count Karl Stürgkh, I. R. Minister für Kultus und Unterricht (Minister of Public Worship and Instruction); * Dr. Richard Weisskirchner, I. R. Minister of Commerce; August Ritt, I. R. Minister for Public Works; Ludwig Wrba, I. R. Minister for the Railways; Knight Joseph von Pop, I. R. Sektionschef (head of department), Director of the I. R. Ministry of Agriculture; Count Erich Kielmansegg, ex-Premier, Governor of Lower Austria; Dr. Robert Pattai, President of the Chamber of Deputies; Dr. Joseph Neumayer, Major of Vienna, Capital of the Empire and Residence. Foreign Delegates elected Honorary Presidents on the Opening of the Congress: Secretary of State von Kázy (Hungary). Dr. Fernando Perez, Ambassador Extraordinary and Plenipotentiary (Argentina). Dr. Karl von Linde, Privy Aulic Counselor, Professor at the Polytechnic School of Munich (Bavaria). Dr. Hermann Hubert, Senior of the Polytechnic Department, Inspector General of Mines (Belgium). 232T'59 6 Dr. Emil Grandmasson (Brazils). Don Francisco Iosé Prado (Chile). *- Hon Té Van, Interpreter Secretary of the Chinese Embassy in Vienna (China). •w E. P. Bonnesen, Professor at the Polytechnic School of Kopenhagen (Denmark): Mr. Charles Charleton, Vice-President and Exchairman of the London Chamber of Commerce (England). ! Georges Villain, Head of the Commercial Control of Railways (France). M. Menozzi, Professor at the Agricultural Academy of Milan (Italy). Dr. Nagaoka Hantaro, University Professor (Japan). Professor J. Ph. Wagner (Luxemburg). --- Don Gilberto Crespo y Martinez, Ambassador Extraordinary and Pleni- potentiary (Mexico). Dr. Kamerlingh-Onnes, Professor at the University of Leyden (Holland). Theo O. Vilter, Pres, Vilter Mfg. Co., Milwaukee (Wis., U. S.A.). C. A. von Krogh, Manager of the R. Railways (Norway). Consul General Leo Hirsch (Paraguay). Eduard Moreira Marques, Secretary of Embassy (Portugal). Anderson, Privy Government Architect and Referring Counselor (Prussia). Dr. G. Moroiano, Commercial Attaché (Roumania). +. Basilius von Dennissoff, Counselor of State, Equerry of H. M. the Tsar, President of the Agricultural Society of the Don-Kuban-Terek Dis- tricts, etc. (Russia). Privy Aulic Counselor Professor Dr. Mollier (Saxony). * Frederic Adolf Georg von Berencreutz, Counselor of Legation (Sweden). M. Butticaz, President of the Swiss Society of Refrigeration (Switzerland). Georg Simitsch, Ambassador Extraordinary and Plenipotentiary (Servia). Fernando G. Lecomte, Agricultural Engineer (Spain) • - Dr. Frederico Susviella Guarch, Ambassador Extraordinary and Pleni- potentiary (Uruguay). * Comittee of the Congress. Presidents: - Dr. Sigmund Brosche, I. R. Sektionschef (head of department) in the Ministry of Commerce. - His Excellency Dr. Wilhelm Exner, H. M. Actual Privy Counselor, Member of the High Chamber, I. R. Sektionschef, etc. -- André Lebon, Ex-Minister of Commerce and ex-Minister for Colonial Affairs, President of the Association Internationale du Froid K. . …& Commissary General: I. Counselor Albert Saborsky. Secretary General: Dr. Alfred Grünberger, I. R. Vice-Secretary in the Ministry of Commerce. Honorary Secretary General: Engineer J. de Loverdo, Secretary General of the Association Générale - du Froids, Secretary General of the France Society of Refrigeration. Reporter for Press Affairs: Alois Schwarz, Professor and Headmaster of Lyceum in Mährisch-Ostrau. Official Delegates. England and Colonies. England : Charles Charleton, Vice-President and Ex-Chairman of the London Chamber of Commerce. R. M. Leonard, Vice-President of the Cold Storage and Ice Asso- ciation. - W. D. A. Bost, Member of the Executive Council of the Cold Storage and Ice Association. New South Wales: Hon. T. A. Coghlan, the Agent General for New South Wales. F. Ch. Govers. New Zealand: Sir William Hall-Jones, the High Commissioner for New Zealand. Queensland: - Major Sir T. B. Robinson, the Agent General. South Australia; Major A. E. M. Norton, the South Australian Government Trade Commissioner in the United Kingdom. Victoria: 3. ~ Sir John W. Taverner, the Agent General. United States of North America. •& John C. Bertsch. * Homer McDaniel, Cheriff Str. Market & Storage Co. Mr. Bruce Dodson, Mgr., Ice Manufacturers' Exchange. Theodor Kolischer. - - E. F. McPike, Agt. Refrigerator Service Bureau Illinois Central R. R. Co. . J. F. Nickerson, Secretary of American Association of Refrigeration. . Dr. Mary E. Pennington, Chief of Food Research Laboratory, Bureau of Chemistry, U. S. Department of Agriculture. – Theodore O. Vilter, Pres, Vilter Mfg. Co. Gardner T. Voorhees, Engineers-Club. Dr. Harvey W. Wiley, Chief Bureau of Chemistry U. S. Department o Agriculture. *. ADDRESS DELIVERED AT THE OPENING CEREMONY, ON THE 6TH OF OCTOBER 1910, BY THE GEHEIMRAT PROFESSOR C. v. LINDE. 11. Retrospective and Prospective Consideration on the Development of the Art of Refrigeration. By Geheimrat Professor C. v. Linde. When reviewing any continuous process of development, not only past ... and present happenings and not merely the state of objective realities will be perceived by the observer, according to his point of view, but the lines and shades of this picture will be much influenced by his subjective jud- - gment, and his limited vision will be unable to spañ the whole historic action. For me, again honoured, as one of the oldest veterans of refrige- ration matters, with the task of making such a survey, the view embraces much actually seen, and this fact necessitates careful statements on my part lest a one-sided view detract from the historical objective. In few other spheres will the three stages of development — the scientific conception, the technical development and the economical appli- cation — admit of being so clearly and exactly traced, as in the sphere of refrigeration. To the extent in which Physics, starting with the invention of the air- pump, discovered the dependence of the temperature upon the pressure, in the case of gases and evaporated liquids, it opened up ways for the pro- duction of refrigerating machines. When the evaporating temperature of water was first reduced to the freezing point, under the glass bell of the air-pump, the principle of the compressing cold vapor machine was established. To this the absorption prin- ciple was added, now nearly 100 years ago, when the effect of sulphuric acid on vapor was first observed. A short time after this the heating noticed in the compression of air led to the principle of the cold air machine. Thus in the first quarter of the last century the physical foundations were found for the three present systems of refrigerating machines. But these children of invention still had to wait several decades for the embodiment necessary for real and vigorous life. The first step was made in England by passing from the vapor of water to the somewhat more volatile liquid Sulphuric w ether. This, the first industrially applicable refrigerating machine, was followed 12 in Paris by Carré's ingenious ice-machine on the ammonia absorption system and further, again in England, by the admirable cold air machine of Kirk. Of these three types not a few were built about the middle of the 19th cen- tury. But nevertheless it was in 1870 still easily possible to count them, and, according to to-day's standards, but very small installations were neces- sary which — at all events on the continent — consisted solely for the production of ice in small cells which had to be lifted out of the salt. solution by hand. - In 1873, on the occasion of the World's Exhibition here in Vienna, an international congress of refrigeration was held, which closely considered the development of refrigeration. * s * It was a congress of brewers, of persons, therefore, who had great need of refrigeration which need they satisfied by storing large quantities of natural ice, and who dealt with the question as to whether there was prospect of satisfying their requirements by means of refrigerating machines, and how such requirements should be satisfied. * - To answer these questions I was called to Vienna, and was able to point to three things in particular: - 1. That theoretically possible relation between the effect and the power applied in a refrigerating machine could be determined by thermodynamics. (For the second time new bases were hereby found by scientific discovery — this time chiefly theoretical – for the production of refrigerating machines.) With this standard it was seen that the effect of the refrigeration machines previously built was less than 25%, so that technical improvements offered prospect of considerable increase ; 2. that such increase was particularly to be sought in the use of more volatile liquids in vapor compression machines whose design should be arranged in a special manner for overcoming the difficulties which at that time stood in the way of sufficiently tight packing against highly volatile vapours in the movable parts; 3. that in the place of the ice manufacture hitherto employed to com- plement the store of natural ice, only the direct transference of the heat from the various processes and rooms could make a rational cooling possible, and that suitable conduit means to this end must be matured. - The names Dreher and Faber, of Vienna, Sedlmayr, of Munich, Jacobsen (Copenhagen), Feltmann (Amsterdam) and others, who have done their part to effect these proposals, deserve to be mentioned beside those, usually quoted in the literature on refrigeration. On the one hand progress - was made thereby in the technical development of refrigerating machines, which immediately raised the effect to 50°/o of that shown by thermo- dynamics to be the maximum attainable, and on the other hand the first. great wave of the economic utilization of refrigerating machines began to flow over Germany and Austria, and then over the United States of North America, and everywhere where downward fermentation brewing is at home. 13 Not only was the building of rational refrigerating machines promoted thereby, but arrangements were perfected which were serviceable and necessary for the direct application of cold before, during and after fermentation in such proportions, that even to-day these great plants are unsurpassed in capacity. After the lapse of another decade a second great wave of the econo- mical use of cold was caused by the needs of England for imported meat, and it extended to the general preservation of fresh killed meat in slaughter- houses especially those of German lands. Besides these two waves, grown in a short period to powerful streams, the production and use of refrigerating plants developped in great variety and in so many spheres that to number them would be difficult and fatiguing. It is clear that this rapid economic growth of the art of refrigeration must have had fruitful effect, both on the technical development and Com- pletion of machines and buildings, aids to the production and application of refrigeration, and also on the economical examination of all physical and chemical processes. Soon the building of refrigerating plants had entered into profitable competition, to the general advantage of machine builders, and the data pertaining to the physical behaviour of bodies employed in refrigeration had been collected on nearly all essential points. - Scientific research, however, has proceeded far beyond this collective - work. After the fine discovery by Andrews concerning the critical state of gases had prepared the way, Cailletet, v. Wroblewski and Olzewski presented our own age with the liquefaction of the supposedly permanent gases and Kamerlingh-Onnes completed this victorious march of the art of refrigeration by lowering the temperature almost to the absolute zero in liquefying Helium. New spheres were hereby, for the third time, opened up to refrige- ration by physics. We know that science did not long hesitate in developping the new conquests for the building and operation of gas liquefying machines and to apply these to new economic uses. Let us review the period which lies between to-day and that first international congress, which in 1873 considered refrigeration affairs in Vienna. It presents to our view a broad well-cultivated field of scientific, technical and economic work. Scientific research has opened the way to the attainable end of temperature diminution. Technics has found the means of following up these path finders, step by step, and of offering new possi- bilities of progress to domestic economy in many thousands of refrigerating plants of the most varied kinds and sizes, from the smallest hand ice machines to the powerful refrigeration centres. Thus from this broad field of work, extending over four decades, a rich harvest has been reaped. It has resulted, moreover, in what is doubtless one of the most notable events of the pre- Sent day, namely, that to-day a second International Congress of Refrigera- tion has met, though but two years ago people connected with refrigeration from all civilised countries of the world assembled in Paris and founded a permanent international association, and that from this movement the for- 14 mation of a large number of national associations of refrigeration have sprung, such as hitherto had only existed in England and North America, Within the last two years an organization of thousands of men has been formed, which seeks to further the progress of refrigeration. To the individual effort in scientific research in the production and application of the re- frigerating machine, there has been added the demand for exchange, and for the collection of the means for and results of such work. Though the creative furtherance be always dependent on the intensiye work of the individual, yet it cannot be doubted that those combined endeavours will produce new effects in many directions, and therefore, in this social sense we may speak (at all events for the European continent) of the beginning of a new era. Of what kind these effects will be, and what results they will produce none can prophesy. It is extremely venturesome even to discuss the probable future deve- lopments of refrigeration, so that I would but try to do so as regards technical development in the closer sense, and with the further limitation that I only touch on suggestions and endeavours already present in embryo or in half formed condition. *. Here I have in mind, on the one hand, the reconsideration of pro- cesses long known in the normal temperature sphere of the old refrigerating industry with the means newly found by technics, and on the other hand the further use of the newly opened up sphere of low temperatures. The evaporation of water by means of the air-pump is known to us as the oldest method of producing cold with the aid of machines. The great volume of the vapour developped in the vacuum made the economical use of it impossible. The endeavour to replace the pump by absorption with the aid of sulphuric acid found no satisfactory technical solution. Thus the vacuum machine remained as a wreck lying by the side of the stream of cold technical development. Lately, however, trials have been set on foot to refloat it. The excellent success achieved by Le Blanc with his jetting apparatus for condensing the steam have led him to extend its suction effect down to the minimum of vapor tension, which corresponds to the freezing point of water. We read of noteworthy results that have been achieved in many cases with this combination through its simplicity. It has also been sought to solve the problem in other ways. Technics has formed new implements in the turbo engine, which work excellently down to the lowest tension of the pressure scale, and playfully handle those great specific volumes. Thus the turbo compressor is now to be placed at the service of the vacuum engine. And the use of turbo compressors is being considered not only for the steam engine, but also for compression machines working with volatile refrigerants. The cold air machine had a fate similar to that of the vacuum engine, The closed Kirk engine was entirely abandoned, and the open cold air 15 machine worked out and improved in England with such great energy and perseverance, was, owing to the comparatively large expenditure of work necessary, only able to hold its position to such a small extent that to-day it plays no part, quantitatively, in the development of refrigeration. Here, too, we know that it is the great volumes which stand as hindrances in the way, and consequently the replacing of piston compressing and expan- sion engines by turbo engines has been taken into consideration in many quarters, and the results that this new solution of an old problem will produce may be awaited with interest. With the well founded advantages admitted for the cold air engine, especially for maritime purposes, the rehabilitation of the closed piston engine with the use of low pressures must also appear promising for the high ab- solute pressures, such as have lately become customary in the technics of the compressed gases. & These suggestions may suffice to show the probability that the two old methods depending on the sole use of water and air may awake to new life in the vacuum and the cold air machines. While we have had to do here not with new cold effects but only with new technical developments, another picture of the future has been opened by the possibility of attaining, with simple machines, the lowest temperatures, at which the formerly permanent gases liquefy. But ten years ago the refrigerating industry moved solely between temperatures whose practical limit but seldom sank below — 20°, and whose attainable limit was fixed by the congealing point of carbonic acid, at some 50 degrees below the freezing point of water. Since then a new cold technics of low temperatures has come into existence and already shows a rapid development. Next I would like to refer to the fact that the chemical industry lately demanded a moderate reduction of temperature below the congealing point of carbonic acid (to about —80 degrees) and the extraction of large quan- tities of heat at such temperatures. This was a task whose solution it was possible to achieve with the aid of the well known cold vapor compression machines, making use of nitrous oxide and of ethyl, and which represents a step between the temperature sphere of the old cold technics and that of low temperature technics. The economic importance of this new low technics culminates in the ability to separate, or to purify gas mixtures which are composed of parts only coercible with difficulty analagous to the precipitation of water vapour from the air, as, especially for the purposes of furnace operations, has been effected during the last decade with the aid of our old cold technics. In the case of mixtures not easily coercible we have either to en- tirely liquefy and then separate by fractional evaporation or rectification, or else to separate the less volatile parts by partial condensation. The best known example of the first manner is the collecting of oxygen and nitrogen from liquefied air, a process which, within the last * 16 eight years, has become such a great industry that the number of oxygen and nitrogen plants in different parts of the world has already passed the first hundred. º An important example of partial condensation is the separation of ~ Oxygen from gas mixtures containing Oxygen, such as water gas, as also the separation of sulphuric acid combinations and other impure substances from gas mixtures, in which only the hydrogen remains unliquefied. The development of this new means of working cooperates with the great development of electro-chemistry and thermo-chemistry, and seems destined to assist in many directions in the important question of the combination of atmospheric oxygen for purposes of agriculture and Science. This short review of the history of refrigeration shows it sometimes as help towards progress in other branches of work, sometimes as recipient of suggestions from new conquests in other spheres — a fruitful changing. effect that continually generalizes the importance of refrigeration. Though it may never equal in importance its older brother fire, the gift of Titan Prometheus, yet the ability not only to raise temperatures high above the surroundings but also to reduce them far below it, has taken its place in the course of human civilisation, and has become one of the elements that are passed on to coming generations for continued progress. COMMISSION I. . Scientific. 19 Experiments at the Cryogenic Laboratory at Leyden. By Prof. Dr. H. Kamerlingh-Onnes. It is a pleasure to me to comply with the request from many quarters for an exposition on the latest operations at the Cryogenic laboratory. In-so- far as they have contributed to the literature during the last biennial period, these operations may be arranged in three divisions: 1. Work on the physical constants of gases and liquids. 2. Collaborations on the physical characteristics at temperatures produced by liquid hydrogen. 3. Work with liquid Helium. Permit me to select from these groups such points as are best adapted for distinguishing the nature of the problems we have to solve, and the technique of the low temperature experiments conducted for their resolution. I. In much of the work I shall discuss I have had the privilege of working in collaboration with Scientists who accepted the hospitality of the Cryogenic laboratory. In one case this was supported by an official corpo- ration, in compliance with the wish expressed at the Paris Congress. I am able to gratefully mention that the Paris Academy placed a sum, from the fund dedicated to this purpose by Prince Roland B on a part e, at the disposal of Mr. Prof. Mathi as of Toulouse. . In the investigations by Mr. Mathi as and myself) the densities of liquid oxygen and its saturated vapor were measured at various temperatures, from the critical, - 119 C., down to — 210 C. The apparatus employed is plainly illustrated by Fig. 1. The pure oxygen is under pressure in a copper storage bottle a, in to which it is distilled by cooling with liquid air. The gas can be conducted either directly or by means of a Cailletet compression tube & into the dilatometer c. The 1) C. R. 151 (1910) p. 213, Comm. from the Phys. Lab. at Leyden No. 117 (1910). ** - 2% 20 dilatometer is placed in a very exact Cryostat of the Leyden cascade. Into the double walled vacuum glass d liquid oxygen is poured for the low pressure and liquid ethylene for the higher pressures. The Cryostat being surrounded by a double walled vacuum glass containing liquid air and . this again by a vessel containing alcohol whose temperature is kept above that of the surroundings, it is thus possible to see the meniscus of the liquid oxygen quite clearly with the microscope e and to observe its level. To determine the volume, the oxygen is led off from the dilato- meter into the volumenometer f, by which its temperature, pressure and volume are measured. The investigations showed that, throughout the whole extensive cycle of its liquid state, the oxygen follows the law of the recti- Fig. 1. linear diameter, discovered by Caillet et and Mathias, that is, that the sum of the densities of liquid and vapour if these are in Saturated equilibrium, is a linear function of the temperature. - - Hitherto this law had only been proved for substances with a much higher critical temperature. The result for oxygen, with its very low critical temperature, is particulary important as confirming the calculations made by Mathias') for substances with low critical temperature. They refer to the factor of proportion of the sum of the densities mentioned with the rise in temperature, the coefficient of direction of the diameter, and explain— its behaviour in respect to the law of corresponding States. * 1) Rapp. et Comm. 1er Congrès International du froid W. 2 p. 145. 21 The experiments conducted in collaboration with Mr. Mathias are - in the line of the operations which form the center of action of the Cryogenic laboratory. The Van der Waals law of corresponding states, (the importance of which was again shown in the liquefaction of Helium) has formed the basis for working out the methods of the Cryogenic Labo- ratory at Ley den for more than 25 years.") That law distinctly marks the necessity of determining the equation of state of gases of simple chemical structure, particularly of those having the smallest number of atoms to the molecule, viz., at that time yet the diatomic. Work is being constantly carried on for the determination of the physical constants of such sub- stances.”) As I pointed out in the notice (Rapp. et Comm. I* Congrès Intern. du Froid, v. 2, p. 121), the examination of the equation of state of gases and liquids must include besides the compressibility the thermal expansion, the vapor tension, the densities of saturated liquid and vapor, the heat of evaporation, the difference of specific heats, the Boyle point, the inversion point of the Joule-Kelvin effect, etc. of simple substances. For a knowledge of the indivuality of molecules and their influence on the equation of state it is also most necessary to have data of the viscosity and heat conduction, which are greatly influenced by them at low temperatures. Moreover the examination of the equation of state for the liquid state can no longer be separated from that for the solid state (coefficient of expansion, elasticity, internal friction, specific heat, etc.). In consideration of the Nernst heat theorem, which becomes prominent with the latter, attention may be drawn here to the importance of vapor tension at low temperatures for the determination of the 2 chemical constants. This seems to lesult in the reduced equations of State of the various substances exhibiting varieties of form, which admit of being arranged according to the critical temperatures of the particular substances. Dr. Keesom and I hope shortly to develop this view more exactly in the volume Physiks of the x Mathematische Encyclopädies. From this point of view the study of the equation of state of Helium at low temperatures gains in importance in comparison with those of other monatomic substances.") I would merely like to pause for a moment on the operations concerning Neon. These examinations") were made possible by the kindness of Herr Ingenieur Claude, who sent me a large quantity of uncondensed gas obtained during Separation of the air, and containing up to 30°lo Neon. Part of the purifying process is shown in Fig. 2. The gas separated from the hydrogen is frozen with the aid of liquid hydrogen. The helium is shown thus —. The 1) Leyden Comm. No. 14 (1899); Suppl. No 9 (1904). *) Since the paper for the 1st Congress, J. P. Dalton, Leyden Comm. No. 109a (1909; H. Kamerlingh-Onnes, Leyden; Comm. No. 112 (1909); C. A. Crommelin, Leyden, Comm. No. 115 (1910). *) And the diatomic substances that are suitable for comparison. 4) H. Kamerlingh-Onnes, Leyden, Comm. No. 112 (1909). 22 - * ~ frozen mass is then thawed and the Neon (shown thus –....— ....— ....) is drawn off, in which operation the nitrogen remains over, in the frozen state. Only a preliminary purification is attained, but this process affords control of the quantity of gas that has to be dealt with. It is so great that I can proceed to add a neoncyclus to the Leyden Cascade. I am most grateful for the generosity with which the Société de l'Air Liquide in Paris set this splendid example) for the advancement of the science of refrigeration through the refrigerating industry, and I venture to hope, that it will find imitation. - - II. With the use of liquid hydrogen for physical experiments we come to the second group of operations. We enter the sphere of lowest temperatures, for which the Leyden Laboratory is especially arranged, particularly for Fig. 2. collaboration work. As I explained in an adress”), several years since, I am always directed in my work by the conviction that a series of questions which present themselves at every step in every direction can only be solved by experiments at low and lowest temperatures. I have therefore made it my special task to work out methods which make such investigations possible and which, if necessary, also make it possible to include in them exact measurements at these low temperatures. As concerns the choice of the questions to be taken up it has always proved most advantageous to me to be guided by the fact that another experimenter was led by his own special wº-s--- 1) I have just received from the Welsbach Light Co. a valuable present of raw Helium, which the director, Herr Miner, had the great kindness to colleet for me while treating a large quantity of Thoranit. 2) Ileyden Commun. Suppl. No. 9. 23 work to the same question that interested me from the point of view of the effect of low temperatures. Then by united effort, material progress could be made within a short time. For judging the importance of the hydrogen temperatures I would like first to point out the hypothesis which becomes relevant through the Nernst heat theorem) in conjunction with the Einstein theory”) viz., that at very low temperatures the heat equilibrium only causes very slight molecular movement. Already at the temperatures of liquid hydrogen this may be so small that the heat movement may be of comparatively little further importance. In other words the freezing point of liquid hydrogen may be but practically equal to the absolute zero point, for the structural”) peculiarities, the molecular and the atomic formation of the substances. If we turn from the form of the molecules to the phenomena of the electron system, which depend upon the temperature, the temperature of freezing hydrogen cannot yet be considered as approaching the absolute zero point. Yet there exist such phenomena for which, as I have previously shown,”) the electrons have also their equation of state, and in which this is such that even when sinking to hydrogen temperatures the electrons, so to speak, freeze to the atoms. In the investigation that I had the honour to make in collaboration with Prof. Lenard and Dr. Pauli of Heidelberg”) such a case was presented by the lasting phosphorescence of sulphides. The temperature of freezing hydrogen is low enough to transfer all the bands of the emission spectrum of this phosphorescence to the lower momentary state; i. e., to reduce the phosphorising substances to such state that only a storing up of the exciting energy and no emission takes place. According to the Len a r d theory, in light-electrical manner within the phosphorising molecules, electrons are thrown off by the exciting energy, from the metal atom that participates in the phosphorescence, and are stored up in the sulphur atom. This storing up of electrons is extremely intensive and complete at the temperature of liquid hydrogen. On warming, the sulphur atoms of the phosphorising centers set the hoarded electrons free: these return to their metal atoms causing them to glow. The glowing of each kind of center and therefore of each band becomes permanent at a special temperature. For some bands this temperature was found to be between —250° C and – 240° C., for others at -255°-C. ') Göttinger Nachrichten 1906, p. 1. Comp. Theoretical Chemistry. 6 Edition, p. 699; Journ. Chim. phys. 8, 1910, p. 228. . . 2) Ann, der Phys. (4) 22, 1907, p. 180, 800. *) An examination of allotropic states was carried out by Cohen and Olie, at the Leyden Laboratory. (Leyd. Comm. No. 113, 1909.) 4) Leyd. Comm. Suppl. No. 9, 1904, Cp, Leyd. Comm. No. 111, p. 3, note 3. 5) Leyden Comm. No. 111, 1909. 24 Fig. 3 shows the important part of the experimental apparatus. The pieces of the phosphors are stuck on to glass plates a, which rest against the reservoir 6, of a Helium thermometer 61, #3. All this can, by means of a screw C, be moved upwards or downwards and turned. For cooling, liquid hydrogen is introduced from the reservoir, and if necessary, the pressure at which the hydrogen boils is lowered. For later warming the phosphorising substance is drawn up; this is further assisted by a heating wire d at the bottom of the hydrogen reservoir. The same illumination attained here by heating the phosphorising substance as a whole, may also be effected by illuminating with ultra-red light, if this radiates upon the excited sub- stance kept cold in the hydrogen. A localized increase of temperature is, then, attained by radiation in the phos- is phorising centers and when the molecule in the midst of the cold substance reaches a suitable temperature it begins to glow. In agreement with the great quan- tities of light stored up at the tempe- reply to ultrared radiation was also found to be very intense. Besides the long lasting phosphorescence the sulphide also showed (as Lenard taught), a short phosphores- cence, which is to be explained by less complicated molecules. This short phos- phorescence is also maintained in liquid hydrogen. In this respect it is similar to the phosphorescence of uranyl combi- nations, which is also of short duration. In the examination of these I was per- mitted to work in collaboration with Henri Becque rel, a man as amiable Fig. 3. as great and whom I can never forget, and his son Prof. Jean Be c que r el. It º: º §33; & ratures of liquid and solid hydrogen, this. was found that the phosphorescence bands of uranyl salts became very narrow and distinct at hydrogen temperatures. This is due, according to Len ard, to the stopping of the heat movement and the regular structure of the crystaline salts. The movement of the electrons, according to this view, takes place in a more orderly manner than at ordinary temperature, while their intensity remains the same. From the movements of the electrons, which are necessary for the explanation of magnetism, it must also be presumed that they too, on sinking to hydrogen temperatures, lose but little in importance. This follows from the examination of ferromagnetic substances and some paramagnetic sub-. stances related to them, in which investigation I had the honour to work •ºw 25 with Prof. Weiss of Zürich.) Unfortunately it would lead too far from the point to explain the results of these experiments. Out of gratitude, however, I must mention them here, because some experiments, easier to explain, were made by Dr. Perrier of Zürich and myself after the same method and with the friendly assistance of Prof. Weiss. These experiments”) which I would like somewhat to explain, concerned the susceptibility of solid oxygen of being magnetized. The most important part of the apparatus used is shown in Fig. 4. A small flat, ellipsoidal bottle a with a long stem & is hung between the poles of the magnet. When filled with solid oxygen it is directed by the field in the same manner as if it were an ellipsoid of soft iron. The bottle is placed in a double walled vacuum glass, into which, in the experiments mentioned, liquid hydrogen was poured. The lower part of the vacuum glass is silvered. The sides of the double tube are but "la mm apart, so that the poles of a powerful magnet, revolving on a vertical axle, can be brought very close to the ellipsoid of solid oxygen which is thus exposed to a strong magnetizing field. It is now necessary to determine the moment of force that the magnet in a definite position exercises upon the ellipsoid of solid oxygen. This is effected by means of a very delicate torsion spring d', upon which the bottle is suspended by its long stem. The spring is hung to the head of a tube e, closed top and bottom but with suitable side openings, which forms a sort of casing, in wich the oxygen ellipsoid is suspended. This is fastened down on the floor of this casing by means of an exceedingly finely drawn platiniridium wire f. To get the ellipsoid of solid oxygen into its place the whole casing in which it is fixed is dipped into the vacuum tube. The determination of the magnetic susceptibility from the moment of the force occurs when the ellipsoid of solid Oxygen is brought into a suitable position between the poles, by revolving the magnet upon its vertical axis. The ellipsoid will follow and thereby twist the torsion spring to a certain degree which is read off with the aid of the mirror. I would like, now, to describe how the ellipsoidal bottle is filled with oxygen. It is brought along the stem and the thin rubber tube g, in connection with the supply of pure oxygen. Then the casing is pulled up the stem, which passes through the stuffing box, in which operation the rubber tube coils up in the open space, and this is continued until the ellipsoid is far beyond the point at which the vacuum glass begins to be transparent. The ') Leyden Comm, No. 114, 1910. *) Leyden Comm. No. 116, 1910. 26 liquid hydrogen is then poured into the glass and the ellipsoid in its Casing pushed down until the oxygen is seen to liquefy. When the bottle is full of Oxygen it is pushed further down until the oxygen is seen to freeze. When a uniform solidification has been attained the casing with the ellipsoid is finally brought so far down that the ellipsoid arrives at the desired position between the poles. I need hardly say that I have given but a superficial account of the most carefully executed operations. With those that relate to hydrogen it must for instance not be forgotten that the least bit of air, which freezes and becomes attached between the poles, can hinder the measurements. The result of our researches on liquid and solid oxygen is chiefly that deviations from the law of Curie, according to which the specific susceptibility would be inversely proportional to the absolute tem- perature exhibit themselves with increasing amount in lowering temperature. The knowledge of these deviations appears to be of importance for the development of the Langevin Theory of paramagnetism,') from which Curie's law is derived. It is possible that freezing of the electrons to the atoms plays a part in the deviations. Ill. It is evident that the last mentioned researches, like so many others, of themselves awake the desire for operations at still lower temperatures. We thus come to the third group of operations, of which I spoke at the beginning, those with liquid Helium. With these one of the first questions was how far it was possible to decrease the temperature by lowering the vapor pressure below the boiling point. As early as 1908 it was demonstrated”) that the vapor pressure could fall to the extent of becoming 1 cm without the helium solidifying: The temperature was then, according to estimate, not much above 39 ab- solute. After this, in 1909, it was successfully shown”) that helium remained in liquid state, even if the pressure were but 2.2 mm. The liquid did indeed gain much in density and rose capillarily on the walls of the vessel, but the helium remained responsive to even small agitation. It might be pre- sumed that the temperature of the liquid then drops below 2:5 absolute. Before I describe how I sought to make further progress, I would like to explain the importance of helium temperatures, by an example of experiments that only begin to offer promise of results when the tem- perature is reduced to the range of those temperatures. I take it again from the study of paramagnetism, namely from the doctrine of the saturation phenomena; i. e., from the deviations of magnetization from proportionality with the field, as these are to be expected according to Langevin's theory. 1) Ann. Chim. et Phys. (8) 5 (1905), p. 70. *) Leyden Comm. No. 108 (1908). 3) Leyden Comm. No. 112 (1909). 27 We have, indeed, just seen that a result of this theory, Curie's law, does not apply well, but if it is only desired to show distinctly the importance that the very lowest temperatures may have, we will be allowed to reason according to Langevin's theory. According to this theory Saturation takes place to a certain degree if a quantity a, determined by the quotient of field-density and absolute temperature a = f ( #). attains a definite corre- sponding value.") - For oxygen at 0° C. Langevin calculates that to raise a to 1 (at which value of a the paramagnetism remains 6% below the amount that is calculated on the supposition of invariable susceptibility), a field of 1,000,000. gauss is necessary. A test by observation is unthinkable, as the most power- ful field of appreciable dimensions it is possible to provide does not exceed 50,000 gauss. With the present magnetic appliances, only values of a = 0.05 can be attained at which the saturation phenomena are too minute to be observed. This is quite different at the temperatures of liquid helium. As according to Langevin the phenomenon is determined by the relation of the field to the absolute temperature, our magnetie field, on sinking from 0° C. or 273° absolute to the boiling point of helium (49 of absolute), appears practically increased 65, and 110 times if we work with helium which boils under 22 mm vapor tension. If with these two figures (65 and 110 enlargements) we think how much pains it has cost to reach from a field of 25,000 gauss which is not difficult to secure, to 50,000 gauss or double, it becomes plain how greatly the low temperatures are neces- sary for the study of paramagnetism. It is actually found that for Oxygen at the boiling point of helium the value a is attained with a field of 15,000 Thus with a field that is easily obtained the saturation phenomena with the aid of liquid helium may be correctly established and thoroughly investigated. - This example of experiments, that are only possible in the domain of liquid helium, suffices to show how desirable it is to extend the domain of helium temperatures as low as possible. As I said I have also tried to do this and although the range research had only the character of preliminary work, yet it is certain that I again got lower temperatures than in 1909. I succeeded in this by evaporating helium in a double walled vacuum glass c (Fig. 5) having a large exit tube &. This vessel was itself immersed in liquid helium and could, therefore, convey but exceedingly little heat to the evaporating liquid. In order to obtain such a protecting bath of liquid helium as was here necessary, it is first necessary to solve the problem of transferring the liquid helium from the apparatus in which it is prepared, into the other glass which is arranged to hold the apparatus that is to be dipped into the liquid helium; this in our case is the double walled ex- perimental bulb. Now the manner in which I obtained the helium bath is *). Cf. the Fig. by Langevin Ann. Chim. phys. (8) 5 (1905) p. 70. 28 not suited to achieve this object with certainty. For when I repeated the ex- periment with a very slightly different apparatus I was not again successful However that may be, in the experiment in transferring the liquid helium. sº | s — L^ º r now to be described I was successful, perhaps by a fortunate chance, in filling the glass c with liquid helium from the apparatus in which it had been prepared, through the silvered vacuum exit tube d, and by means of repeated new inflow of helium, whose vapor es- caped at /, to insure its remaining full. Regarding the preparation of the helium led off to form the bath in this experiment, an idea is afforded by the sketch Fig. 6. To afford a general idea of the entire experimental apparatus, a schematic sketch of the cycle is also appended in Fig. 7, that furnished the hydrogen for the ex- periment. From the gasometer g the compressor p conveys the hydrogen into the li- quefying apparatus, where it is cooled by liquid air evaporating in a vacuum, and then expanded through a regenerator coil 7: . enclosed in a Dewar glass, in prin- ciple as in the air lique- fying machine, whereby the liquid hydrogen is collected in the reser- voir m and from there siphoned off into the 29 Dewar bottle i. The half hectolitre vessel o is first filled with liquid air with the aid of the Leyden cascade. Twenty four litres of hydrogen : J. SN ſ 2- -- -* -- 2. * -- - -: - - ~ -: --- -- - 2. 2. - ; * i % § ; - B.i.§ § : º 3.º ** * * 2- - ; 2. º.J * Aº º ºº º; :- ~ * # º | § | __959 ſº Şā; yº - - - - - e ºs s = * ** g |__269 |º Fig. 6. were prepared, which sufficed for driving the helium apparatus and for the further requirements of the experiment. The liquid hydrogen cº-º-; i``'``'`-----...-...-. !. º, >----------, - .. ..r-ilr: i; ! !... " * ! - || ! ºrs ºº:: ; ; § º § & # QN £. § º § § § § * *~ ;Fºº º § º §§ º § § Elºğ & - W § * * º wal tº §º § furnished by the hydrogen circulation is transferred to the Dewar bottle i after the helium circulation (Fig. 6) and is evaporated in the space ſt 30 provided for this purpose at the air pump. In Fig. 6 the helium circulation- is shown by — From the gasometer / the compressor k conveys the gas into the liquefying apparatus, which is first cooled by the liquid hydrogen evaporated in vacuo, and then expanded through the regenerator coil g in the Dewar glass. In the first experiment of liquefaction of helium - a-" lº) Fig. 8. the gas was protected in the lower part of the vacuum glass f against heat by a space filled with liquid hydrogen that was protected against evaporation, and the liquid helium collected there. In the present experiment, however, the liquid helium flowed through the exit pipe down into the glass, where the helium bath was into which, as already stated, the apparatus dipped 31 with which the experiment proper was made. The arrangement of the liquefaction is somewhat more fully shown in Fig. 8. The helium bath c is protected by a double walled transparent vacuum glass containing liquid hydrogen, which is itself encased in a double walled transparent vacuum glass containing liquid air, and this again in a glass containing alcohol which was kept at a somewhat higher temperature than the Surroundings. If all is prepared with sufficient care the walls of these glasses remain perfectly clear and the helium in the experimental apparatus a-o may be quite distinctly seen. Within a-o a small magnet was hung on a silk fibre in order that, should the viscosity of the helium increase it might be observed. This did not serve however, but light taps were sufficient to show that the helium remained liquid even at the temperatures attained. I pass over several other parts of the apparatus because they were of no service in this experiment. I must only mention a vacuum glass e (Fig. 8, cp. also Fig. 5) of extremely small dimensions in which I had hoped to see the last signs of liquid evaporation. I did not succeed, however, in Suffi- ciently screening the radiation, so that it did not perform the services mentioned The glass a-o and the apparatus with which it was connected by & were previously filled with pure helium. In order to get liquid helium into a -o the pressure of the gas was raised "/.. of an atmosphere above atmospheric pressure. The helium then was condensed on the walls a-1 and flowed into the glass a -o. This was filled to above the rim of the vacuum insulation. In evaporating a liquid under low pressures very large volumes of vapor have to be conveyed away. In order that but a slight pressure difference may occur between the surface of the evaporating liquid and the point at which the pressure is measured, the connections especially when the gas is not at low temperature must be very large. To control the gases it is necessary to have pumps with ample suction capacity very large even at the low pressures. In the experiments only about 2 cm3 of liquid helium evaporated per hour. Yet two compound Burckhardt pumps had to be used, a large one with a suction volume of 360 mº per hour compounded with a smaller one of 10 mº per hour; at the lowest pressures a rotary Siemens pump was used with suction volume of 28 mº per hour compounded with the large Burckhardt vacuum pump just mentioned. It was possible in this manner to maintain at à a pressure determined with the aid of Macleod pressure gauge, of about */; mm., and after estimating the corrections the evaporating pressure remained below /; mm. Again, therefore, we have advanced considerably further than in 1909, when the evaporation took place under 22 mm. The difficulties which attach to the measurement of these temperatures are not yet quite surmounted. We must, therefore, rest satisfied with an approximation of the temperatures 32 achieved. On the basis of the law of vapor tension, which, however, can. only be approximately given, and of the observed critical pressures, it is probable that a temperature somewhat below 2° absolute has been attained, that is an absolute temperature, which is only about the 140* part of that of the freezing point of water. I close with the assurance that I shall endeavor to make still further progress. 33 Cold Without Fuel, and the Consequences. -- By Ch. Tellier of Paris. The title of this paper may appear contrary to the laws followed in applied science. 4 * This is not the case. Fortified by this certainty, I take the liberty of enlarging a little upon this subject before the International Refrigeration Congress at Vienna, making, however, the observation that in writing fuel, I do not necessarily mean to say that heat may be dispensed with. Such a pretention would evidently be out of all reason, because it would assume making something from nothing, which is impossible. Having made this introduction, I would say that in refrigerating ‘machinery, if it is necessary to provide heat to work it, this heat, instead of being derived from fuel could in a certain way be derived from the very action of the apparatus. To be more precise, let us start with known facts. For this purpose, notice what happens in the most widely known Rind of refrigerating plants, those which work by the liquefaction of gas by means of mechanical compression and its ultimate vaporization. Here we find there exist negative and positive calories produced by their own action. * The negative ones are those given up by the body being refrigerated. The positive are those which are given by the compression and lique- faction of the gas used. The former are carefully collected; they are what constitute the desired refrigerating action. The latter are thrown away and rejected by the condensing water, which disperses them. * It is really these latter which should be collected, instead of being lost; so as to be transformed into power to produce the mechanical work inecessary for the operation of the apparatus. In order to appreciate clearly this side of the question, notice first what happens with ammonia, the substance most generally employed in the 3 34 .* refrigerating action produced by mechanical compression and liquifaction machines. If we vaporize it at 5° C, we find that it will have a tension of 3.45 atmospheres, giving us a corresponding refrigerating effect. Assuming that this substance is liquefied at + 15° C, we see from . this that a pressure of 7.13 athmospheres (Regnault), or an excess of 3.68 atmospheres is opposed to the operation of the machine; this, it should be noted, is in theory. ! This resistance must be overcome by outside motive power. Hence the consumption of fuel, and the loss of the latent heat given up on liquefaction, about 318 calories per kilogramme. - But instead of throwing away this heat, might we not be able to recover it and use it in place of the coal consumed as we suggest to be possible? -- - For this purpose, it would be necessary to effect liquefaction at a temperature high enough to be ultimately of use, or to get a definite idea (we always base the facts upon Regnault), about 95° C. Having this warm water we could apply it to vaporize liquid ammonia. From this we might perhaps derive the power used to work the apparatus. From this we can use the liquid medium carrying away the heat of compression, for the recovery of the power spent, disposing the medium in such a way that pressure is augmented by the heat of compression, giving up its heat to the vaporization of the substance used, wich we assume for the present to be ammonia. The high pressure of this substance may on first thought be objected to. But at present methods of construction allow of the employment of these pressures. They are exceeded in machines using carbonic acid gas, and no one urges that they be done away with. There are, then, no obstacles in this direction. º * Thus, then, it may be seen from the above that the production of cold without fuel is a thing quite possible of realization. This is not all. - - Assuming that it is possible to produce cold without fuel, an important result immediately follows. This result is that we can, by this means, obtain power without fuel, but not, it must be understood, without heat. To be precise upon this point, we must see whence we are to obtain the heat of which we speak, which is necessary, and which, however, we do not wish to derive from coal. It exists almost everywhere in nature. - It is available for our use, in all the water we meet from 200 to 30% C, perhaps below. - , - - - - Take for example the Red Sea, whose permanent temperature is 30% to 320 C. } - 35 If we apply this water to vaporize ammonia we will immediately have a pressure of 11 to 12 atmospheres, which we could apply to any kind of vapour engine that we wished to employ. This is, then, the power found, and its origin is irrefutable. But every- thing has not been said. *. We have, indeed, found the power, but to obtain its permanence with a constant quantity of the vaporizing liquid employed, which is a necessary condition, this body must be promptly condensed and liquefied, thus serving indefinitely. But here lies the difficulty: - - In the neighbourhood of warm water we may possibly find cold water, which may serve for liquefaction. But this is an exceptional case wich we can only count upon rarely. We must then find, in order to keep within really practical means, another way. $ 4 We have this at hand, because we have just seen that we may produce cold without fuel. g - We discover here a considerable surplus of power, entirely without cost, and which we may use for motive power in a number of ways. I need not impress upon you the consequences of this application. I will merely say that the first of these would be the free production of electricity. - It must not be forgotten that this, thus obtained, would be the most complete manifestation of progress which we can imagine. .* This would mean the substitution of an adaptable active and ever ready power, for the bodily labour of man, leaving to him his most noble prerogative, the use of his intellectual energy. Such is the result of obtaining free motive power through refrigeration. It is for this reason that I have taken the liberty of calling the attention of the International Congress of Vienna to this part of our work. 3$ 36 The Use of Cold in Bacteriological Examinations. By Professor Dr. Oscar Bail (Prague). The use of cold in experiments dealing with the formation and pre- vention of bacterial infection soon gained great importance, and its practical application was rapidly extended. The specimens, for the most part from animal bodies, which form the object of experiment are of so perishable a nature that but a short stay in ordinary temperature suffices to change their condition, and only the use of cold can ensure preservation and con- sequently the possibility of thorough examination. More is at stake here - than, for example, in the preservation of other organic, animal stuffs which, as is the case with animal foods, have only to be protected against decomposition. - { For even if such is made impossible by absolutely sterile obtention and storing of the material, for instance of an animal serum, yet if cold is not made use of changes take place in a short time which often render the material useless. Thus serums from animals in fresh condition have quite peculiar effects on bacteria as also on the cells of other animal tissue, and their study has led to the most important progress in our knowledge of infection and immunity; at normal temperatures, however, these quickly spoil, and we know no other means of preserving them than storing the serum at low temperature, best in a frozen state. Not only serum and other stuffs obtained from animals but also bacterial products require cold for their preservation, and these products are as important for the study of the origin of many diseases as for the preparation of the antidotes. Many bacteria form very deadly poisons which may be easily maintained in artificial cultures, but they can only be kept up to full strength for longer periods by making use of low temperatures. Thus it came about that in the earliest times means for the maintenance of low temperatures formed indispensable . adjuncts to the laboratory. At first the ice-safe was employed, and it is still made use of for ordinary purposes. As the institutes grew, however, and as the experiments were extended and applied in practice, the ice-safe 37 soon proved insufficient and wasteful. Now nearly all large institutes which deal with such experiments and the application of the results to our knowledge of infection and immunity, are provided with refrigerating machines which enable larger quantities of such stuffs as easily become useless to be kept for long periods in a frozen state. It is out of the question to obtain healing and preserving serums without such refrigeration apparatuses, and they are absolutely necessary wherever we have to guarantee the unchanged effectiveness of serums that must serve for testing newly produced serums. Of great interest and importance for the arrangement of small insti- tutes was the construction of a small freezing apparatus called "Frigos, ex- plained by Morgenroth, and first made by Messrs. Lautenschläger in Berlin. In principle it is based on the production of low temperatures by a mixture of ice and salt by which the stuffs are frozen and kept in this state by the use of the best insulation possible. Naturally only very small quantities can be preserved by this means, but with care the apparatus works very Satis- factorily and cheaply, and it may be used to carry out the more exact experiments where refrigerating machines cannot be erected. While cold thus only serves for aiding other experiments it is at the same time also applied as direct means of examination. Buchner was the first to use it in an intelligent manner for the perishing away and subsequent extraction of cells, in order to free their stuffs without injury. It has since become very usual to freeze out cells whose intercellular effects it is desired to examine and which are of very perishable nature. The cells are ruined but their active contents, e. g. those of fermen- tative nature are preserved and can be examined together with the remains of the cells burst by the freezing, or often without them. The cooling process, which is carried out either by means of a freezing mixture or with the aid of the low temperatures of refrigerated rooms, represents an extremely valuable aid to such experiments. The low temperature of liquid air has also been used, especially by Macfadyan, in the bacteriological Technic for the obtention of the cell con- tent of bacteria which is distinguished for its poisonous qualities and other interesting peculiarities. The cultures are frozen quickly with the cold given by the liquid air and thus prepared for destruction which takes place in friction machines, which are kept uniformly cold by the same means. Thus the juice of the cells of these diminutive organisms is obtained free of other liquid and in greater concentration, and can then be further examined. 38 Artificial production of low temperature in the Biologische Versuchsanstalt. By Dr. phil. Hans Przibram, Privatdocent of the University and Direktor of the Biologische Versuchsanstalt in Vienna. (Translated by Dr. Margulies). So long as students of zoology and botany were satisfied to treat biologicol problems from the stand-point of comparative-anatomy and to construct theories of developmental history merely with the aid of mental processes, the modern refrigerating industry interested them no more than t was useful for them in preserving killed material or in making sections with a freezing microtome. But as biology passed from the comparative description of living organisms to an analysis of the causality of their vari- ation, and as it has abandoned the tendency to theorize concerning deve- lopmental processes and began to search for proofs thereof, it become urgent to find new technical means not only serviceable for mircoscopic studies, and preservation and preparation of killed animals and plants, but more particularly for bringing up live organisms under the influence of isolated factors. New means were thus needed, whereby to study separately the elements of climate, which in combination produce such an effect upon the flora and fauna of each locality, that peculiar animal and plant types are characteristic of different territories. Temparature is one of those important factors to be studied, and while for many years past it was possible to obtain high temperatures wiht various heating appliances, it was very difficult to obtain at all seasons of the year low temperatures without the help of freezing machines. Experiments on a small scale were repeatedly made with low tempera- tures, where a small receptacle was cooled either with ice or with flowing cold water; for instance, Jower's experiments on the production of variations . in the potato-bug, or Ostwald's experiments on water-flees. Icechests were also used in the numerous experiments on butterfly pappae, where great and transmissible abnormalities were caused by the short but extreme fluctu- ations in temperature. - * Such methods, however, fail completely where it is necessary to rear large animals and plants, especially for long periods of time, even for several generations. The Refrigerating Industry was, therefore called upon to construct such chambers which could be available for experiments with any desired low temperature. One would think, as the author himself had thought when the Biologische Versuchsanstalt was first organizcq (1902 39. that well equiped cold storage establishments, where in every large city rooms could be rented at reasonable prices, could be utilized for biolo- gical researches. It soon became apparent, however, that special accommo- dations are required in rearing animals and plants, which are essentially different from what is afforded by most business establishments or even hygienic and bacteriological laboratories. * - Above all it is important in the interest of the investigations to build the temperature chambers (for definite high and low temperatures) as nearly | alike as possible. The possibility of using the cold-storages is thereby ex- cluded, since there are no rooms adjusted for high temperatures. In the next place, there must always be a free access of air; for this reason, the bacteriological freezing chambers are of little use also. It is, furthermore, well to orient all chambers with their windows southward, so that the win- dows in the doors on the opposite, northward side would permit the rearing of cultures in diffuse light. An effective source of cold is necessary for this condition which is indispensable for the favorable cultivation of green plants and of most light- loving animals. On the contrary, chambers with very low temperatures are of little importance for long continued experiments, because growth and reproduction tend to cease under a temperature below zero. A Biological Institute is not completely furnished without a freezing outfit, for reasons already indicated. On choosing a refrigerating machine it must be ascertained first of all that it does not employ any harmful gases, for it is known from von Molisch's investigation that even small quantities of lighting-gas or of nikotin produce a detrimental effect upon the growth of not over-sensitive plants; ammonia or sulphuric acid would, therefore, be very much more injurious. Compressed air or carbon dioxide alone may be used without hesitation. In the particular case of the Biologische Versuchsanstalt in Vienna — at present the only one with a freezing outfit — a carbon dioxide machine is employed (Riedinger, Augsburg-Wien). 1 omit the description of details which will be found in the report of the articles to be inspected at the Congress in the Zeitschrift für Eis- und Kälteindustrie. The Arrangement of the temperature-chambers (cold and warm chambers) and the importance of exact temperature experiments I have already discussed in a paper read before the International Congress of Physiologists in Vienna, in September 1910. Here I wish only to point out some of the problems, which we shall be able to study experimentally in the cold-chambers: the acquisition of a white winter fur by polar animals; the increasing number of viviperous organisms at low temperature; the shortening of the extremities in higher latitudes accompanied by the increase of the body in general, and many others. 40 THE RELATION OF MICRO-ORGANISMS TO Low - TEMPERATURES. - By DR. EDWIN F. SMITH, Pathologist, United States Department of Agriculture, Washington, D. C. A great variety of studies by many individuals covering a period of years have shown that for best growth (sometimes for any growth at all) it is necessary to cultivate certain microorganisms at blood tem- perature while others thrive best at open air temperatures. This, however, by no means expresses the relation of all microorganisms to temperatures. We know that certain organisms which cannot grow at blood temperature grow very well when the temperature is raised Io° to 20°C. or more above this temperature. The optimum tem- perature for the growth of some of these thermophilic organisms lies as high as 60° to 70° C. (140° to 158°F.) It is probable also that organisms exist which can grow at temperatures but little under the boiling point of water at sea level. On the other hand some organ- isms are known which cannot grow in summer heats, i. e., at tem- peratures as moderate as 30°C. (86°F.), but which grow very well when the temperature is depressed to 20°C. It is probable that there are also organisms which would find even 20°C. above their maximum temperature for growth. For some time organisms have been known which grow at o°C., and others at temperatures but very little above this point. Researches are continually increasing the list of organisms wheh will grow at these low temperatures. It is also now known by researches of Rahn, Brown & Smith, Michigan Agricultural College (Tech. Bul. 2, 1909) that a certain Torula will grow in butter at temperatures as much as 6° below o°C., even in the presence of very large quantities of salt. The temperature relations of organisms is an interesting field, and one which thus far has not been cultivated as thoroughly as it should be . The writer has been for a long time in the habit of test- ing every organism studied in his laboratory to know not only its optimum temperature, but also its range of temperature, and he has frequently pointed out the desirability of applying these tests to all fungi and microorganisms of economic importance. Following suggestions made by him Dr. Thom applied these tests recently to a large series of Penicilliums grown and studied by him, with some rather interesting results which have now been published (Bulletin No. 118, B. A. I., U. S. Dept. Agric.) The normal changes which take place in ripening fruits are known to be purely chemical ones, and some of these may be retarded by low temperatures. Whether the slow changes that go on in stored animal foods at low tempera- tures are to be attributed mostly or altogether to oxydations in- dependent of microorganisms, or whether low forms of life also play a part in these changes are matters to be determined by experiment. We have very convenient apparatus for determining middle temperatures in the ordinary thermostats, but so far as the writer knows less convenient ones for maintaining continuously higher temperatures, i. e., temperatures from 60° to go”.C. (I40° to 194°F.) There is also a fairly satisfactory apparatus made by Paul Altmann, in Berlin, for temperatures ranging from 0° to 20°C., or with the use of a small lamp at one end of the thermostat, temperatures from o° to 40°, 50° or 60°C. The writer has used this apparatus, which con- tains Io chambers, for low temperature work, but has never tried the lamp attachment. In the Washington climate he has found it pos- sible in the cooler chamber to maintain a temperature of o' to O.5°C., for very considerable periods of time (weeks) by keep- ing the apparatus well stocked twice a day with cracked ice. The next warmer chamber under these conditions has usually a temperature of 4°, and the one next higher about 7° or 7.5°C., and so on up to about 20° for the warmest chamber. So far as known to the writer there is no convenient moderate priced apparatus for temperatures below o°C., but we need an apparatus of that kind not to cost more than four or five hundred dollars which shall give us readly temperatures ranging from o' C. to mins Io' or minus I5°C. with suitable arrangements for maintaining constant temperatures at either of these points or intermediate grades as desired. A good apparatus of this kind ought to find a moderate number of buyers in the various laboratories of the world. Those who have the ad- vantage of an ammonia ice plant can, of course, arrange temper- atures to suit themselves. 42 The Application of Cold in Surgery. By Primararzt Dr. Hans Lorenz, Privatdozent für Chirurgie, Vienna. As in every branch of human knowledge so, too, in Surgery modern discovery has caused many old-fashioned, deeply rooted views and customs to be discarded. Similarly our ideas as to the effects of refrigeration and its province of application in respect to surgery have been exceedingly modified. Cold compresses, the application of ice-bags and cooling apparatuses once, played an important rôle especially in fighting inflammations. It was supposed that cold should be used to combat the increased flow of blood to the area of inflammation and the resulting redness and heightened tem- perature; and, further, that such procedure was against inflammation wanti- phlogistics, and able therefore to have a favourable influence on the inflammatory process. $º The first person to condemn this ancient method of dealing with infectious inflammatory processes was Landerer (in 1885), who contended that the increased flow of blood and heightened temperature at the inflammed part was desirable and advantageous, and denied the policy of attempting to retard it. *- Since that time, though only quite gradually, it has come to be recognized that the cold treatment, especially in the case of the ice-bag still beloved and misused, is a mistaken one in the great majority of cases of inflammation, that the hyperemia with which the diseased organ reacts against the inflammation is a healing process and that this process is aided, not by the use of cold but on the contrary by the application of warmth. # The contention so often heard, even in these days, that the bacteria which cause inflammation are checked in their propagation by the application of cold, and would be aided therein by certain degrees of warmth, is not to be maintained ; for quite apart from the fact that the - bacteria are under altogether different conditions of life in living tissues to those under which they stand in the eprouvette, the other fact must not be forgotten, namely, that by the use of sufficiently great cold, not only 43 the bacteria but also the tissues attacked by them would be seriously harmed. We know to-day that the minimal cooling to which living tissues may be subjected for long periods without severe injury, is in no way sufficient to check the growth of the inflammation germs, and that, on the other hand, the inflammation causes light necrosis, or a perishing of the tissue, if the area is artificially rendered relatively bloodlees — as the cold treatment strives to do. The systematic use of ice-bags, cold compresses and cooling appa- ratuses in cases of inflammation is therefore to be condemned. Moreover most patients find the application of warmth far more agreeable than that of cold. I have dealt with this matter at greater length than a procedure of merely historical interest deserves, in part because even in these days cold is often thoughtlessly made use of when warmth is required, but above all because the application of cold still enjoys considerable popular favour, and the doctor who takes steps against this abuse often runs the risk of being considered ignorant. Just as ancient and old-fashioned as the use of cold in cases of inflammation, is its use in cases of wounding. In cases of open, bleeding wounds the application of cold bandages was formerly very much in favour, especially as first aid, but to-day this is tabooed, if only for aseptic reasons. For subcutaneous injuries, whether only the flesh or also bones and joints are affected, cold bandages and ice-bags are even to the present day much in use. Two effects are expected from the cold, retarding the bloodflow, and allaying pain. Naturally we know to-day that a compressing and quieting bandage is in every respect of greater effect than, and therefore preferable to, the ice-bag or cold bandage. But there is no possible objection to placing an ice-bag over the bandage, thereby making use of the pain allaying effect of the cold. -* Cold is with success applied as a styptic in cases of spontaneous bleeding of mucous membrane, especially from the nose, gums, tongue, throat and stomach. Lower degrees of cold acting on the surface of the body appre- ciably diminish pain; in so-called Minor surgery extensive use is made of this property in order to render small superficial operations, such as Small abscess cutting, less painful. This so-called cold anaesthesia has come into general use especially as a consequence of the discovery by Richardson (1866) of the ether spraying apparatus. The evaporation of the sprayed ether produces a temperature of 15° C. on the affected skin. Still more intense is the effect of sprayed chlorethyl (Kelen), which may be purchased of every chemist in small glass or metal flask with con- Venient stopper, and which is, to-day, indeed, the only preparation made use of for cold anaesthetics. 44 Chlorethyl boils at + 11° C., so that the warmth of the hand alone suffices to drive it from the flask. It produces a temperature of — 35° C. on the skin, if this is dry; under the influence of this extreme cold ice is formed in the skin, which becomes suddenly white, hard, and insensitive. But the anaesthesia thus produced is only superficial and of short duration, moreover the freezing of the skin and the subsequent thawing cause severe pain, so that the method, even apart from the fact that it is only usable for small and superficial operations, cannot be called an ideal one. Con- sequently for small aseptic operations it has been displaced by the various kinds of injecting anaesthetics, while for operations for inflammation, when the injection of cocaine solutions and such like are risky or uncertain, pre- ference is mostly given to ether. g Thus also for anaesthetic purpose the use of cold in surgery has now become limited. On the other hand a method is beginning to be very general in which great cold is used to destroy affected tissues that lie on the surface. First employed by Americans (Pusey, Feissler, A. J. and E. Ochsner) the method became known in Germany last year through the information given by Sauerbruch, and to-day there are quite a number of publications that speak very highly of the successes of the method. It would lead too far to go more exactly into its technicalities, which are, however, very simple ; only the most important shall be mentioned. The procedure makes use of the great cold of the snow of carbonic acid. Liquid carbonic acid is allowed to passthrough the valve of a carbonic acid container into a bag held before it, e. g. a cotton glove; thereby an intense evaporation of cold is produced, which causes part of the carbonic acid itself to freeze to a white snow-like mass at about — 80° C. Particles of this snow are then either simply laid or else pressed on to the tissue to be dealt with, for a shorter or longer period of time, ac- cording to the intended effect. The effect, remarkably enough, is quite other than that of hot glow, which is also used at times to destroy certain tissues. Namely, if the carbonic acid Snow be properly applied no sloughing of the tissues takes place but the less vital affected tissue is injured by the cold in such a manner that absorption occurs, and the healing sometimes follows even without any visible scar, and without a drop of blood being lost. - By means of the method thus sketched out it has already been possible to heal blood vessel Swellings, warts, pigmentary moles, and other innocent superficial skin defects, indeed, even superficial cancer of the skin; favou- rable influence upon tubercular disease of the skin has also been recorded. It is reserved for the future to fix the exact indication bounds of this very promising method ; but it can already be said that the method, which is distinguished by great simplicity and by painlessness, and which gives brilliant cosmetic results in that direction to which it points, can hold its 45 Town very well in definite cases with the other methods known to us; es- pecially the Radium and Röntgen therapy of certain superficial affections may be expected to suffer severe competition from the method, for it is not only much simpler and cheaper, but, as far as can at present be jud- ged, free also from the possible disagreeable complications of the Röntgen procedure. - C on clusions: The use of cold as a means against inflammation, so much favoured in former days, must now, with the present standard of knowledge, be re- jected; even as pain allaying and astringent means in the case of wounds, cold is to-day but little employed; as astringent against certain mucous membrane bleedings it is still applied. Cold anaesthesia for the purpose of Minor surgical operations is still . much in use, though, on account of various disadvantages, considerably limited by other anaesthetic methods. In the province dealing with tumours, the application of intense cold may be still more used as a means for reducing superficial swellings in a special manner, and may compete with other modern methods of treatment, especially with Radium and Röntgen therapy, in certain circumstances. 46 The Employement in Therapeutics of Liquid Air at –180° C. - By Dr. L. C. Query, Paris. At the first French Refrigeration Congress which met at Lyons in 1900, I presented a paper dealing with the action of liquid air at — 180° C on living organisms and organic tissues. At that time I mentioned some in- teresting therapeutical experiments on obstinate skin diseases, by spraying with liquid air, insisting not only upon the certainty of the results, but also on the harmless nature of the treatment. - I have continued these experiments the results of which I have the honour to place before you. *- It is well known that all skin affections caused by abnormal condi- tions of the system, or, to use the accepted term, all the affections depen- ding upon an idiosyncrasy, have no chance of disappearing under any tre- atment whatsoever, unless this idiosyncrasy is first removed ; in other words the general treatment should precede or accompany the local treatment. Besides affections due to the state of the system, there are others. which are entirely local, of an infectious or parasitic origin, and for these last, more perhaps than for others, spraying with liquid air gives results, which may be considered in the majority of cases as decisive. I mentioned at the Lyons Congress, the success obtained by spraying with liqued air in the treatment of eczema. Cases of fifteen or twenty years standing, were successfully treated in November and December last, after having resisted a number of other treatments, and up to the present, the eczema has not returned or broken out on any other part of the body, as sometimes happens in such cases. It would seem as if the disease were entirely destroyed on the spot. I would mention a case in particular of a patient fiftysix years old, who has suffered from the age of 18 years with a general eczema, which when treated with emolient baths, followed by the application of various oint- ments, had disappeared from the surface of the body, but had settled . . locally on the neck and behind the ears for ten years"). After two spray- 1) >Revue Générale de Froid 4 February 1910. 47 ings at an interval of 8 days the eczema completely disappeared, although the patient was diabetic with 35 grammes of sugar per litre. The eczema has not reappeared on this patient since the twenty-fifth of May. Diabetes. therefore is no obstacle to the liquid air treatment. Seborrhic eczema is susceptible to treatment by liquid air in the same way as simple, dry or moist eczema. A patient who had suffered with seborrhic eczema of the scalp for 8 or 10 months, has got rid of this by the first application of liquid air spray. A return occurred in the five or six succeeding days but less intense and extended, and yielded to the second and third application of liquid air. Psoriasis is also favourably influenced by liquid air. Two young men of eighteen and twenty years of age, and a man of forty-five were treated for this affection. In the case of the two former, neither was affected with a concomitant disease, which is always recognised in the form of local spots of psoriasis on the elbows and knees. Two applications of the spray on each at an interval of eight days made the spots completely disappear, and these spots have not returned now after several months. The third case, was general psoriasis, covering the arms and legs of the patients like a veritable shell. From all places where the spray was applied the spots of psoriasis entirely fell away, to form again the following days, but thinner and smaller. Applications were necessary but the patient left Paris and I have not seen him since. All wart like affections of the hands and scalp which I have treated by liquid air, also disappeared completely on the first or second applications. & One of my patients, a sufferer from psoriasis, also had a coloured mark on the forearm, covered with hair. I applied spray of liquid air to this mark, which disappeared while the hair which was local remained upon it. Spraying with liquid air did not attack pimples, which fact has caused me to try them in the treatment for scurf. Here again after two or three sprayings I have seen the hair reappear in the very centres of the spots, and grow three or four millimetres in fifteen days. Note that the spray was applied not only at the centre, but over the whole spot of scurf. I have mentioned above the treatment of coloured marks; I have also had occasion to treat vascular marks, which have also disappeared. The treatment of warts and corns by liquid air has not yielded such Satisfactory results. Besides liquid air is not a corn-killer, its lightest appli- cation causes continuous pain like that caused by atmospheric changes. How are these liquid air applications made? What is their anatomical and pathological action? Also, what is the permanent result from the point of view of appea- rance and are the cures permanent? 48 The spraying is effected by means of a special Dewars flask furnished with a stopper having two tubes. One end of one of the tubes is com- pletely submerged in the liquid air, the end of the other only reaches the surface. The tube dipping into the liquid air has an enlargement at its other end which is provided with several small perforations and is covered with asbestos threads. This end should be held two or three centimetres. from the surface being treated. The outer end of the other tube is fitted with a simple rubber atomizer bulb. The skin of the patient is covered locally with adhesive plaster, in which an opening is cut uncovering so much of the affected area as is to undergo spraying. These sprayings should last from 10 to 20 seconds, and be repeated two or three times, according to the case in hand, at intervals of eight or ten days. - From an anatomical and pathological point of view, the sprayed sur- face whitens immediately, from the freezing of the tissues, returning to its original condition at the end of 2 or 3 minutes, but presents also a local condition due not only to the oxidising of the tissues, but also to vaso- dilation succeeded rapidly by vaso-constriction. - Some hours after the treatment, the crusts of eczema loosen and fall off, or even the skin rises in blisters such as are formed by small burns. Then the blisters break, letting out matter, and the mortified skin dries up. and falls off, leaving fresh skin to form underneath. This skin generally retains a slight brownish coloration which differs from the surroun- ding skin. y Generally, patients feel a sensation of local heat which sometimes lasts two or three hours, but which is not painful, and never causes any febrile reaction. As far as appearance is concerned, except the slight brownish dis coloration of the skin already mentioned, I have never observed any loss of tissue leaving Scars. As far as results long after treatment are concerned, for one and a half years since I treated the first case of chronic eczema with liquid air I have not seen this eczema return. The other kinds of eczema and psoriasis. were treated more recently (about seven or eight months ago) and have not returned. If they did return, I should not hesitate to resort to the same treatment. It would be of interest to apply the same treatment to all kinds of local affections of the skin, and there is good reason to suppose that fa- vourable results might be obtained in cases of Lupus, perhaps even Leprosy, and Ulcers of all kinds in a more or less advanced stage, before which or- dinary therapeutics is often unavailing. It is essential to use the liquid air with care, the spraying being only for a shost period and repeated as necessary. Liquid air may thus become a powerful adjunct to therapeutics, especially as it is quite harmless in use. 49 The Use of Cold in Dermatology. By Prof. Dr. Eduard Schiff, Vienna. The application of cold in Dermatology is as old as the hills and in the ear- liest times had already passed from the sphere of popular medicine into that of science. Even to “civil present day cold compresses and the use of ice in cases of Erysipelas and skin affections have not been abandoned. Of late Ether- chlorate (Aethylum chloratum, Chlorethyl), which when used as spray causes direct freezing of the skin, is much in favour. Büdinger (Münch. med. Wochenschr. Nr. 27, 1909), recommends, for instance, that warts be treated with ice application. He treats the warts with a Chlorethyl spraying, once or twice repeated. The wart falls off partly and partly shrinks. Two years ago Pusey recommended the Carbonic acid freezing process in Chicago. Zeisler has worked this method out for Dermatic purposes. Mm. L. Heidingsfeld (Liquid Carbonic acid snow in Dermatology, The Ohio State Med. Journ. 1908) made use of the method introduced by Pusey in cases of Lupus vulgaris, Verrucae, Epithelioma, vascular and pigment naevi for removing tattooings and particularly often for Lupus erythematodes. In cases of vascular and pigment naevi he attained especially good results Fabry (Archiv f. Dermatologie u. Syphilis, Bd. 10, Heft 2 und 3), and Fabry and Zweig (Münch, med. Wochenschr. 1910, Nr. 19) have furnished detailed information regarding technical features of the Carbonic acid freezing process. Both writers describe the Pusey process as a simplification and im- provement in the treatment of Verucae, of the Tyloma and the Clavus. The bits of snow are pressed in sprayers and applied in the form of thin or thick sticks. The skin must not be exposed to the cold for too long a time, nor may too large areas be treated at one sitting. The process is, moreover, not quite free of pain. If it is only desired to freeze small areas the treat- ment can be effected ambulatorially. If larger areas or numerous small areas are to be treated, then it is to be recommended that the patient be under hospital care. As a rule an exposition of 30–60 seconds suffices. Care is necessary, especially with young persons. The smallest doses are at first applied. If these cause no reaction, the doses and time of exposure are 4 50 slowly increased. No lasting injury results if the skin is not frozen longer than one minute, and apart from idiosyncrăcies, such freezing must be described as harmless. Fabry and Zweig (l. c.) tested the effect of carbonic acid snow on an animal. The reaction set in later in the case of this animal (a rabbit) than with men. The area frozen for the shortest time produces the largest blister, the shorter the exposure the deeper action has the cold. Freezings of longer than a minute render the superficial tissues firm and hard so that the effect of the cold cannot penetrate. Further a longer exposure leads to such con- siderable contraction of the blood vessels and lymph vessels that exudation and blister formatičn are prevented. Accordingly, as this trial on the rabbit shows, freezing should not be effected for a longer period than one minute. . . Zweig has recommended the carbonic acid snow process for circumscribed skin affections on account of the simplicity of manipulation and the good results. (Münchn. med. Wochenschr. 1909, Nr. 32). With the aid of the Pusey procedure a cold effect is produced up to —90 degiš-. Naturally it is a matter not of the specific effect of the carbonic acid but merely of cold. Zweig and Fabry (1. c.) treat various circumscribed skin affections, such as, Naevi of all kinds, Angiocavernome, Teleangiektasien, Lupus erythematodes. Lupus vulgaris, Tuberculosis verrucosa of miners and finally Epithelioma, with carbonic acid snow. Verrucae vulgaries are subjected to an exposure of 20 to 50 seconds duration. - The snow ring should be twice as large as the size of the wart. After the cold application a Quaddel develops, and later a blister with serous content, and the wart is loosened from the corrium papillae texture. The wart is then cut out, the blister contracts and heals under Airole, Dermatol or Zinc salves. One large Clavus was treated at a single sitting on about 20 small areas for about one minute each. Within two days a large blister formed on the sole of the foot, in the head of which the separate Clavi were. After removal of the blister an epidermis formed within eight days. Tylome on the palm of the hand are cured in a similar manner. Hoffmann, Vetel, Strauss, Sauerbruch and others have written on the use and successes of the Pusey procedure. There is also a warning voice that must not be neglected. Lucio (Gazz. degli osped. 1909, S. 664), warns us against the procedure. He observes that with Angiomen and Naevis pig- mentosis the freezing produced with carbonic acid snow cannot be relied upon to give unquestionable success. He prefers operation or Thermocauter. According to my experience the Pusey procedure is to be recommen- ded for many and various reasons for specialist and general practice. The initial pain, which is often rather severe, soon passes off; the apparatus is very simple and can be made use of in the consultation hour without spe- cial assistance. Certainly I would express a warning that it should not be used to too great an extent out of the hospital. I would not, for instance 51 ‘. . freeze more than five or six areas close together at one sitting. If we do not exceed an exposure of one minute, or if we give the shortest neces- sary exposure in each new case, and if we advise the patient that he must keep the area treated quiet (under a protecting cover put on by a doctor), until healed, if, finally we do not treat more than five to six adja- cent areas at one sitting, then, with the Pusey carbonic acid Snow, we shall achieve very good results with the most various kinds of circumscribed skin affections. Cosmetics especially gains an excellent procedure for cir- cumscribed skin affections in the freezing method. Con clusions. 1. Cold has been made use of in medicine (in the form of cold compresses, ice, etc.) since the oldest times. Nowadays Chlorethyl is used for the same purpose. - 2. Pusey of Chicago first recommended a new procedure by the So-called carbonic acid snow for healing various skin affections: Lupus vulgaris, lupus erythematosus, pigmentations, naevi, warts, epithelioma. 3. The technique consists in rolling the carbonic acid snow into a hard ball and pressing this firmly for a short time (30–60 secs.) upon the affected area. Different areas must be consecutively treated, it being avoided to treat large areas at one time. 4. Experiments on animals have shown individual peculiarities. Sometimes the reaction takes place early sometimes later. It is dangerous to allow the carbonic acid snow to act for longer periods, on account of possible necrosis. 5. No specific effects. - 6. Very satisfactory results (Zweig & Faby) in cases of Naevi, Angioma cavernosum, Teleangiektasie, Lupus vulgaris, Lupus erythematosus, Tuber- culosis, Verrucosa cutis, Verruca vulgaris, Clavus, Tyloma, Epithelioma. 7. The process is almost entirely painless, cosmetic results are very Satisfactory with good scar formation. Simplicity of apparatus and technique. 4% 52' The Application of Cold in Dentistry. By Oberstabsarzt Dr. Sickinger. Pardon me if I do not give a properly completed lecture. In response to your kind invitation I have hurried directly from the glaciers, and will merely say a few words about the use of cold in dentistry. - There are three great methods which have rendered mankind excee- dingly great services. - The first is operation without pain, the second is operation without loss of blood, and as third I would like to add operation without bacteria. * If we could be so fortunate as to unite all three in a single means, such would indeed be the ideal. - As regards narcotics I must add a few words by way of introduction. The first narcotization was effected with Chloroform, and we have only a happy chance to thank for the fact that this magnificent means did not fall into premature discredit. Hofrat Wiesner related the incident but lately. A patient was to be narcotised with chloroform. The assistant clumsily let the chloroform bottle fall and as there was no substitute at hand, the pa- tient was simply not narcotized. Fate had it that this patient died. Had chloroform been made use of in this case it would never more have gained an entrance into Surgery. & f I will not occupy your time with details as to how chloroform and ether etc., are mixed, in order to render the use of narcotics generally free from danger. - I cannot too positively assert the dogma that no dental operation whatever justifies a general narcotization, because such always involves a certain amount of danger for the patient, quite apart from all consideration of the evil after effects. I myself, as president at a commission on this subject — I think it was at Cassel or at Breslau —, had to fight hard for these views with those present, and found great support from Prof. Bönnike of Prague and many Viennese colleagues. Therefore attention should with justice be directed to so-called local anaesthetics. Such were effected for a time by injections of cocaine, adrenaline, etc., and against such I quite openly . 53 also express a warning. Therefore we must greet with especial pleasure the means offered, by producing temperatures far below zero, of obtaining an almost complete substitute for narcotics. There is, for instance, chlor-ethyl which employed as spray so enormously reduces the temperature and with this the sensitiveness that, in most cases, a tooth may be painlessly extracted. That cold may also be used in dentistry as a means for differential diagnosis and how far this use is applied in dentistry I will not discuss here in de- tail, because I believe that it is more in place among specialists of my own branch. *** - 54 Experiments on the change of hardening processes of hydraulic binders at low temperatures. By Bernhard Kirsch, Prof. der Technischen Hochschule, Vienna. In the time of fero-concrete buildings, it is hardly necessary that I emphasise the fact, that the question of the influence of frost on the har- dening process of hydraulic binders is an eminently important one. A study in this direction is therefore entirely justified. There was only a possibility that it might appear superfluous for thc reason that these influences were already sufficiently known and studied. When we consider, however, that doubts still exist as to whether our present conception of the hardening process is correct, I think that trials which directly show the influence of cold on the hardening process are always welcome. It cannot satisfy applied technics to hear suppositions, on the basis of a still uncertain hardening theory, as to the manner in which low tempe- ratures influence the consolidation process. The series of observations that I beg to present here should be extended to concrete bodies of larger dimensions, but arrangements failed me for accommodating such volum- inous objects in freezing rooms. I therefore make do with cubes of 7 cen- timetre edge, made with normal sand in the proportion of 1:3. For the expert it will suffice to state, with regard to the particulars of construction, that the norma of Austria were strictly observed. The conditions in the erection of buildings served as guide for the programme, and here three cases may especially be considered: 1. The concreting is done at a temperature above zero and frost enters shortly afterwards, or 2. the concreting is done during frost weather and warm weather enters later, *- f or 3. frost and thaw weathers repeatedly alternate. To be as Sure as possible I carried out seven different series of trials: A. 7 days air storing. B. 7 days frost storing. * C. 4 days frost storing, then 3 days air storing. D. 4 days air storing, then 3 days frost. 55 E. 1 day air storing, then 6 days frost. F. 1 day air storing, then 3 days frost, then again 3 days air storing. G. 2 days air storing, then 2 days frost, then again 3 days air storing. Tabular arrangement of results. Pressure resistance in kg/cm3 Series Storing -- 1. Trial 2. Trial 3. Trial 4. Trial Average value * º tº º º 285'6 A 7 days air 272.3 293-0 - 288-O 289°O (290-0) * ſº tº * 79-O B 7 days frost 76-0 85-5 82:0 72°6 (81:2) 4 days frost 2312 C then 219-0 || 234'6 240'O 231'O (235-2) - 3 days air 4 days air ^ a D then 234'O | 29O-O 256'O 292.0 & 3 days frost 1 day air ſº E. then 174-0 | 180°O 18O-O 184:O dº 6 days frost - 1 day air then 259.5 F 3 days frost || 2860 256'0 244-0 || 252-0 & * then (2647) 3 days air 2 days air . then 295.5 G 2 days frost || 3140 298.0 276.0 294.O * then (302.0) 3 days air When the trial bodies were made the cement and water and also the normal sand had the temperature of the laboratory. About 10 minutes after the addition of the water the cubes formed were stored according to the above series A to G. Thus, for example, the cubes of series C, ten 56 minutes after the addition of the water, were placed in the ice-safe, which had a constant temperature of 13° to 15° below zero. The ice machine was stopped during the night, but the temperature did not rise more than 2 to 3° by the morning, so a good frost temperature was maintained. . After seven days' storing the pressure trials were carried out direct from the store, that is, the cubes taken from the ice-safe were pressed in a frozen state, when perhaps 10 minutes of thaw time elapsed before the moment of breaking. The resistance value, therefore, of series B., which was kept the whole 7 days in frost, contained the combined effect of ice resistance and eventual hardening during the frost temperature. The figures in brackets in the last column give the average of the three largest values in each case; in the consequences, however, nothing will be changed if the bracketed values are taken in place of the others. Before discussing these figures I would like to speak shortly about what would be expected theoretically; and here it is necessary to take a present day conception of the hardening process as basis. I choose the in- teresting and ingenious theory of Dr. Michaelis sen, of Berlin, as it is of most recent date, and has many supporters. The hardening process may be considered as follows: the mixing water from the cement clinkers (which represent a solution, — very super-satur- ated with chalk — of chalk, silicic acid, argillaceous acid and iron acids, to which about 2 per cent gypsum are added), immediately dissolves chalk. silicate of alkali, calcium sulphate, calcium aluminate, and calcium ferrit. Owing to slight solubility in concentrated chalk solution Calciumsulphate- aluminate, Tricalciumhydroaluminate and ferrit soon separate in the form of needles or little tablets. As soon as the chalk concentration is great enough, a Hydrogel, poor at first in chalk (very similar to the silicic acid Hydrogel) also separates. This continually takes up more chalk by absorption, while, on the other hand, the water is withdrawn from the Hydrogel of the not yet decomposed chalk grains; it thickens more and more on the upper surface of the grains and finally congeals to a hard water-proof Gel. The process, therefore, begins by dissolving chalk in water, and is im- possible in frost. If the frost does not immediately set in, there will, indeed, already be a Hydrogel formation, but so long as there is frost, the water cannot be withdrawn from the Hydrogel through the not yet decomposed chalk grains; that is the hardening process stagnates while frost lasts. It is therefore to be expected that mortar which immediately after being made is placed in frost will not harden so long as the frost remains. The whole of the period of frost storing must therefore be deducted from the total time since the making, in order to get at the time of hardening. Series B of our trials will probably exhibit no resistance and the ob- servation result 79 kg./cm” appears contradictory. Yet this is only apparent, for the cubes were tried immediately on removal from the ice-safe after a 57 lapse of , at most 10 minutes, in a still frozen condition. The pressure resistance of pure ice was fixed by professor Frühling (see volume for 1885, of "Zeitschrift. des Vereines deutscher Ingenieures). Our cubes, however, withstood the treble amount, and this is quite understandable, because we had to do with a mortar. If the binding be neglected, a mortar mass con- sisting of grains between which there is frozen water must yet possess a kg/cm2 ** 400 –º- 300 200 2 -º-mºh- H00 -º- --— *E. • g # tº *: t § C 2 * - *: § * | º 5 *: r: tº słł fr; CN H º c c & ‘O * --- O 1. 2 3 4 5 6 7 days . £reater resistance than does pure ice. It must, it is true, be presumed here that the grains have a greater resistance than ice. The same process occurs with every substance consisting of particles and a binding base mass, let us Say for short a binding mass. The pressure resistance, that is a slant section through the cube (the well known cone formation), will then be chiefly de- termined by the proportion of the two substances. If the binding mass is prevalent, so that the grains be apart, then the inner friction of the binding mass is decisive; if the grains are packed so that only the empty spaces between them are filled with the binding mass then the section through the whole cube can only be made if the overlapping parts of the grains be cut 58 of For the same reasons the pressure resistance of walls is less than that of the stones, because the mortar, as a rule, at all events at first, possesses a lesser resistance than does the stone. In walls made with hydraulic mortar it sometimes happens that the mortar is harder than the stone. Good bricks have a resistance of from 100 to 200 kg./cm”. Portland cement mortar can attain to from 300 to 400 kg/cm3. - From these remarks it will appear explicable that the cubes of series B could exhibit a certain resistance, and it is entirely correct, that this resistance is greater than that of pure ice, because the frozen water as binding mass only filled the spaces between the sand and cement grains (the latter in uncombined state also acting only as sand). # - The six remaining series confirmed the result very well, which was to be expected. If the frost storing be neglected the resistances form a curve, as function of the air storing times, which is in form entirely probable as hardening curve. We have in order: Series E. 1 day air 179.5 kg/cm2 (1692) 95 C. 3 33 - 39 |2312 y (246.5) » D. 4 » , 268.0 m (268-0) 33 F. 4. 35 33 (1+3) 259.5 99 (268-0) - , G. 5 , , (2+3) 295.5 m (280.5) » A. 7 285.6 m (2900) Here only series G departs somewhat from the compensation curve. The compensation values resulted according to the accompanying diagram: the diagram numbers are added to the above numbers in brackets: For the rest, I would merely like to draw conclusions from these expe- riments. It is true, the hardening of the mortar is stopped by frost, but the mortar is not in any way injured by this. It hardens quite normally when the frost ceases. From this it way be concluded that building work, namely walls and concreting, can be done during frost weather without danger; it is only necessary that the scaffolding remain until such period has elapsed, after the frost has ceased, as is ordinarily required in warm weather. 59 Cold Destructive to Monuments. By Hofrat Prof. Dr. Josef Neuwirth, Wien. It is not without some trepidation that I take the liberty to call the attention of an assembly of such eminent technical experts to a question of general importance. Your labours are directed in theory and practice to the advantageous application of cold; they turn the apparently repulsive into the useful, making it serve present day requirements; and I ask if your rich experience cannot find ways and means of applying cold to, or preven- ting its influence against, the preservation of our monuments, nowadays a highly valued gift of culture. A still growing wave of present interest is shown in all states for the endeavours towards preservation of monuments, and of the home. The aim of these endeavours is that the artificial and natural monuments be main- tained in as unaltered a condition as possible, and that the most various delights and specialities of our native land be preserved. All the monuments of the world, as they stand, - with the exception of the more weather proof bronze casts — and apart from accidents not to be foreseen, are at the mercy of the destroying influences of time. The recognition of this fact unites those who esteem the cultural value of monuments in efforts for their preservation by fighting their foes. Among these latter is, it is to be hoped in ever decreasing frequency, the hand of man and his ignorance, but more particularly the effects of time, weather and other atmospheric influences. Against these the measures employed by the officials appointed for the Care of monuments can only have a limited effect. Frost has a prominent place among the influences which are injurious to monuments, and if it is not to some extent fought against and limited, it constitutes a growing danger for the life of the master pieces of man's sculptural abilities. Just as the doctor knowing that he cannot maintain human life inde- finitely, yet continues his efforts and applies every ingenuity to its preser- Vation, seeking as far as possible to eliminate the causes of destruction, so do we consider it to be our duty by preventative measures to protect monuments practically to the end of their existence, bearing the germ of natural decay in themselves, and to defer their final collapse as long as possible. The moisture rising from the ground, or produced by rainfalls, attacks both shell and core of a monument; but, apart from this, experience teaches us daily that especially variations of temperature and the consequent shrinkage and expansion of the material cause displacement and changes of stability, loosening and falling out of binders etc. They vary according to the nature of the material; thus tests conducted by a commission appointed by the government of Saxony established that in the slime-ore and so-called tonic cements of certain kinds of stone the absorbed water first loosens the mortar and stone by dissolving and carrying off the particles of cement, then breaks off bits of cement during freezing and thawing again, destroys the soundness of the stone and favours the formation of sand from the loosened quartz grains. These experiences require to be turned to account through endeavouring to use well dried, solid, and weather proof material, or through impregnating the material with a stone preserving substance. With other kinds of stone containing much quartz water only rises in con- sequence of capillary attraction and in which continuous cement is not present, the splitting effect of the freezing water is considerably lessened, and it appears that by the choice of material alone a favourable condition of preservation is discovered. Thus, for measures for preserving monuments the use of a material that is less easily attacked by cold is of great im- portance. But the knowledge of the various values and weather proof qualities of the different kinds of limestone and sandstone does not alone suffice, if the best protecting means for the particular climatic conditions are not settled for these kinds of stone. For there remains for the care of monuments not only the question of a choice of material that will overcome as much as possible the dis- - advantages of cold, but also the most important point as to whether there exist means of regaining for a stone in course of decay, or already partly decayed, its original Solidity, or, at least, of permanently stopping the pro- gress of decay. The idea may well force itself upon us of meeting the in- jurious effect of cold on the condition of monuments in a manner similar to that employed against other enemies, namely, by the greatest possible elimination. The decomposition of soft stone through moisture, in com- bination with dust and other dirt and changes of temperature, in places with neither light nor air, crypts, little used passages, or ground moisture in walls, may be remedied or brought to a stand-still for a long period by extracting the moisture, drying, airing, inserting insulating layers, building drains, etc., with more or less complete success. Professor Rathgen of Berlin, celebrated as a preserving chemist, under- stood how in an ingenious manner permanently to regenerate salt impreg- nated antiquities of stone or stone-like material, which appeared to be hope- lessly sacrificed to decay, by means of steeping with water, thus by remo- ving the salt which was the cause of decay. - 61 Such successes lead us to apply the ideas of prevention also to in- juries through cold, and to suggest whether cold, which is able to stop de- composition, and decay in so many things, might not be applied to the preservation of monuments in the sense of diminishing decay. In the case of the protection of monuments, especially of building and plastic statuary, we have not only to preserve the material but also the artistic form which is the thinner outer surface material, often of unusual fineness of expression, and is really the most perishable part of a monument. This 2 epidermist of the work of art, compared to which the inner material represents little value, is the most valuable and decisive for the total im- pression; but like the skin which covers the human body is subject to, and exposed to every possible outward influence, sunshine and rain, heat and cold, and, particularly in the transition from one to the other, to numerous attacks and changes. No wonder that just as we seek to keep away the feeling of cold from the surface of the skin, by means of gloves and warm clothing, we should also consider the prevention of the evil effects of the weather upon the outher layer of monuments, due to the influences of air and water and cold, by means of a covering or impregnation of even greater resist- ance to weather and higher compressive strength, or by means of a coating of paint that offers a similar effect. It is not my intention to give a complete list of impregnating materials. It is enough to refer you to the various impreg- nation trials with oil, wax or paraffin, or to the use of potassium silicate, fluargen, testaline, etc. But the application which should protect the outer surface of a monument, the covering which shall close the pores of the stone and keep out water and cold, is by no means free from objection, and it is a question whether the increased preservation will not be dearly paid for by loss in other ways. In comparison with other means for preserving stone, the fluates that cause a silicious coating of the surface increase the resistance of and harden the layers that they impregnate, but they do not completely close the natural pores of the stone and any moisture still in the stone can therefore evaporate. Other impregnating substances, however, close the pores com- pletely, and thus, by preventing the moisture from evaporating, aid the evil effects of cold weather. Where, however, the stone is very much weather- worn, so that, for the successful application of the Kessler fluates, the at- tacked surface (which often presents the finest artistic intentions) must be Scraped and pared down, this operation — in works of great artistic value, whose finely executed profile can no more stand being pared down by the centimetre, than could the ornament, continuous cutting away from the body – will result in the direct sacrifice of part of the real value of the monu- ment, as happened when the treatment with fluates and silicate of potassium was applied to the pyramids of the uneven surface of the tower of the dome at Meissen, which were pared away down to healthy stone layers. Impregnating substances that resist the cold by completely or partially closing the pores could also be recommended as preventative of 62 decay, yet doubt arises through the influence of these substances upon the colour. This is dulled and deadened by Tetraline, somewhat deepened by wax and turned dark yellow by linseed oil, whilst fluate is the only substance which but slightly affects it. Thus the XVI century tower of victory at the ruins of Stolpen castle, in Saxony, at first showed a slightly glittering surface after treatment with fluates, but this passed off with time. According to various observations, however, sandstone when treated with fluates assumes a dead surface more than lime stone and calcareous sand- stone do. The much employed oil paint coating has an unartistic effect, and detracts from the fineness, especially of the sculpture,and although it hinders the penetration of damp from outside, yet it does not prevent the damp rising from below, which, together with the effects of cold, destroys the interior. The stone, therefore, especially if not quite dry originally, soon begins to decay. Very unsightly evidences of decay develop with silicate of potassium long used for world-wide application. - - Thus, for instance, our beautiful Karlskirche, now being restored, ex- hibited very serious changes in the material under the silicate of potassium coating, due to damp and cold which could not escape through the impreg- nating layer. The different stone impregnating substances, which could also serve to keep out the cold, have thus also varióus disadvantages; not one of them can be recommended generally for all kinds of stone, but only special examination of the individual kinds of stone for resistance to damp and cold will ensure successful choice. Accordingly, to obtain reliable data as to how one should proceed with the protection of monuments against in- jurious influences, under various climatic conditions, it will be necessary to institute systematic impregnation tests in different places, under different climatic conditions, on different kinds of stone, and on monuments in different stages of decay, and to watch the effect of such tests through a number of years, especially as regards damp and cold, with exact notation of temperature variations, rains, etc. That partial or entire prevention of damp can greatly reduce the destructive influence of cold, against which a protective coating does not suffice, must remain as guide. Another kind of protective covering having greater dimensions, is the wooden housing erected in many places, during the cold season, over ex- posed monuments, to keep off the chief enemies to preservation, change of weather, rain and frost. Under such the picturesque town or place, or- namented by a monument whose object is to permanently commemorate prominent personalities or celebrated events, is converted during winter into a veritable burial ground for monuments. 3. That such boxes do not serve as ornaments in a town, and become a persiflage of the object of the monument we are able to convince our- selves, here, every year. It would be well worth greater endeavours, to find means which, when using a material less able to withstand weather effects, keep off or reduce as far as possible the injurious effects of winter weather 63 so that such boxes could be dispensed with without giving occasion for censure on the ground that works of art had been inconsiderately exposed. In the middle ages the more lasting oil paint covering was preferred to ground colours for outdoor sculptures and also clay figures, mostly glazed when in the open, were almost invariably polychromed. The respect for such treatment of sculptures in the open is not yet regained for our time. To preserve the natural appearance of the material of monuments in the open, and to avoid the impression of an imitation (like a certain town hall, impregnated even during construction), the protection sought can naturally not be satisfied by the mere application of an impregnating substance. Finally the most important specimens of monumental painting, the frescoes on the exteriors and interiors of our churches and other public or private buildings, also suffer from unfavourable climatic conditions, especially the damp and frost of northern climates. A long lived ornamen- tation of buildings in southern lands, they quickly succumb to destroying influences in central and northern Europe where again the effects of damp and cold play hand in hand. These work, above all, upon the decomposition of the background; they force their way ruthlessly into every little crack, long invisible to the eye, and after often long years of mali- cious, combined work completely destroy large pieces of the background. Where remains of such paintings are brought to light, after removal of the layer of colour intended for their protection, great difficulties are often encountered in the means of preservation, as under atmospheric influ- ences and altered light effect fading often sets in, which apparently neces- sitates the application of a protective coating. This must be applied - only with the greatest care, in order that the artistic value of the drawing and colouring be not immediately, or after a time, for-ever dulled, the effect of cold must also be taken into account. I have appeared before you, more to suggest than to explain in detail in order to attract the attention of the most eminent circles to the appli- cation of their efforts to the preservation of monuments also which, hitherto, have not been able to look upon cold as a friend. Perhaps I may hope that my words may lead to the question of refri- geration as monument preserver being placed on the programme of one of the next congresses, because of your researches, and that a method may be shown to us of applying hitherto inimical forces to the preservation of one of the great cultural possessions of mankind, of protecting ourselves success- fully against injury, and of applying other momenta of refrigeration directly for the preservation of monuments, for a satisfaction to ourselves and an elevating pleasure to coming generations in artistic cities of the future. Warm to the task of placing cold at the service of this great end! -- - - - - - - - - -º-º-º-º- * *- 64 The influence of cold upon the construction - of building. By Leopold Simony, Architect, and Dr. techn. Emil Artmann, Professors at the Technical University in Vienna. - Would you kindly permit me to call your attention in my own and my colleague Professor Artmann's name, to a seemingly remote subject, the thorough investigation of which lies in the interest of a mode of building answering the requirements of Hygiene. It is the question of the influence of cold & upon constructions in general and upon buildings in particular. These effects of cold which chiefly make themselves felt in an unfa- vourable sense concern the resistance of the various building-materials ac- cording to the nature of their chemical composition and their physical properties under the influence of varying temperatures. These effects of cold further determine in an important manner the character of the separate parts of the building to be constructed of these materials as well as their composition to complete architectural forms. Careful studies with respect to the testing of material as a rule enable us to recognize the presumable resistance of the building-material under the influence of frost, and give us, if not adequate at any rate sufficient data, to form — on choosing the material — a probably suitable decisionſ Hence if generally the question of the choice of building-material with regard to the requisite qualities is not very difficult to determine for the builder, he is on the other hand concerning the resistance of complicated building-parts and architectural forms composed of these, solely dependent on the experiences hitherto often resulting from quite one-sided observa- tions, as well as upon conclusions derived from our knowledge of building- material. This fact is the more to be regretted as just in regard to buildings economical considerations essentially influence the construction, and the in- creased requirements of Hygiene would on the other hand sometimes de- mand a complete deviation from the modes of building practised up to now. It is just this obscurity that particularly in building dwelling-houses as well as factories and artisan-work-shops frequently causes fresh mistakes; *- 65 and on the employment of new building material and constructions only too often produce intolerable conditions in a sanitary and economical respect. We should certainly not fail to recognize the fact that numerous in- vestigations and efforts made with this view have yielded remarkable re- sults and led to noteworthy conclusions, but it may indeed be asserted that scientific research in this field neither keeps nor has kept pace with that in other kindred technical branches, as the processes which are to be taken into account in this case are of a very complicated nature and therefore require for their explanation extensive, and hence very expensive experiments. The question of creating x building-laboratories « to be devoted to scientific research in the department of: *The Science of building-con- struction in generals has not hitherto been approached in Austria and builders have utterly failed to avail themselves of the opportunity given at all new buildings, to carry out scientific experiments during the different Stages of construction. The question of creating such x Building-laboratories* and their special tasks is not to be contemplated here, but the attempt may be made to direct the attention of larger circles to a hitherto sadly negleted field of technical activity that in the truest sense of the word conduces to deter- mine the very interest of the individual. Even if it has up to now been the principal task of the Refrigeration- Congress to submit for thorough discussion only those questions which refer to the production and utilization of cold, it might with regard to the fore- going remarks also be admissible to call the attention of the Congress to the hitherto little contemplated injurious influences of cold upon the con- struction of buildings and to the preventive measures required by it, in order to bring about in this manner the scientific solution of the questions which seem most important in this case. I therefore beg to move: * that the I Section of the Refrigeration-Congress resolves, to include in the programm of its scientific discussions the subject in question viz., ... •The effects of cold upon the construction of buildings. Moreover the col- lection of Scientific materials as revealed by careful investigations should be submitted for consideration in one of the next Meetings. 67 Report of Proceedings of Commission I. 1* Sitting, 6* October, 1910. The sitting began at 2 p. m. and lasted until 3:30 p. m. Honorary President: Prof. Kamer ling h- On nes; President: Hofrat Prof. Dr. v. Lang; Vice-President: Prof. Dr. W. Sui da and Prof. Dr. K. Ko be s; Secretary: Dozent Dr. Fr. B Öck. - The President, Hofrat Prof. Dr. v. Lang after opening thes itting, addressed those present as follows: Ladies and Gentlemen Permit me to add my heartiest greetings to the expressions of friend- ship that have been offered to you on all sides to-day. I convey to you at the same time the greetings of the scientific world of Vienna, who follow the discussions of the Congress of Refrigeration, and especially those of our Commission with the greatest interest. There are indeed met together here from all parts of the world, those who shine through their scientific work in our department and who have laid the foundations for the enormous progress of the Refrigerating industry. Rest assured that the recollection of having opened this meeting will ever afford me the greatest pleasure. (Applause.) A The President then introduced to the assembly the two Vice-Presidents of the Ist Commission, Prof. Dr. W. Suida and Prof. Dr. K. Ko be s, also the Secretary, Dozent Dr. Fr. B Öck. * As Honorary Presidents of this Commission the follawing were proposed and chosen with lively expressions of approval: Se. Hoheit Prinz Roland B on a parte (France); Prof. Bonnese n, technical university Copenhagen (Denmark); Geheimrat Mollier (Prussia); Geheimrat v. Lin de (Bavaria); Ing. George Clau de (France); 5% 68 de Lover do, General Secretary of the Association Internationale du Froid (France); - - Prof. Kamer ling h-O n n es (Holland); Mr. Bost (Great Britain); Dr. Ludwig Ball a i (Hungary); Dr. Th. Freiherr v. Nat of p (Hungary); Theodore O. Vilter (United States of America). Prof. Kamerlingh-Onnes then took the chair and delivered the following address: Mr. President, I highly esteem the honour you have done me in propo- sing me as honorary president and gladly take the opportunity to declare here how great has been my desire to make your acquaintance, remembering the great benefits that the study of your works has afforded me. I consider the fact of being permitted, at your side, to lead the discussions an act of international courtesy to all men of science, who have come here to take part with Austrians in the work of the Congress. Once more I express my thanks for this great honour. (Loud applause.) The Honorary President, Prof. Kamerlingh-Onnes then stated that Prof. D'Ars on val was unfortunately prevented, by illness, from attending the meetings and proposed that the deep regret of the Members present be expressed in a telegram to the following effect: » A Monsieur le Professeur d'Arsonval. > La première commission du Congrès regrette mille fois que vous Soyez empéché de prendre part au congrès frigorifique à Vienne.< This proposal was unanimously agreed to, and the day's programme was then taken in hand. - - A slight change was necessary in the order of reading the papers, and Herr Privatdozent Dr. H. Przibram was the speaker, his theme being * Concerning refrige ration at the institute for biological experiments. (See p. 38.) As no question was raised Prof. Kamerlingh-Onnes thanked the speaker for his interesting dissertation and stated that the remaining papers would be reserved for the next sittings. * > For the sitting on the following day Geheimrat Dr. v. Lin d e or, if he should be prevented, Geheimrat Mollier were asked to occupy the chair. Vice-President Prof. Dr. Suida then made known that the sitting . arranged for Saturday October 8*, would be omitted, and in place thereof there would be a visit to the *Hygienic and sero-therapeutic Institute.<. The Honorary President repeated this information in the French language and then closed the sitting. - 69 2” Sitting, 7” October, 1910. The Sitting began at 10 a. m. and continued until 11:30 a. m. Honorary President: Geheimrat Prof. Mollier; Vice-President: Prof. Dr. Wilh. Sui da ; Secretary: Dozent Dr. F. Erb a n. - Geheimrat Mollier opened the sitting and stated that owing to the absence of Dr. Edwin F. Smith, the paper submitted by him on the >Effects of Low Temperatures on Micro- or g an is m sº would be read by Mr. Theo. O. Vilter and introduced him to the meeting. Mr. Vilt er first apologised that the printed copies of this work had not yet arrived, owing to delay in transmission from Havre, and expressed the hope that on Monday they would be at the disposal of those interested. At present he had but one copy, from which he then read in the English language. (See p. 40.) - The Chairman thanked Mr. Vilter for reading the paper and inquired if a discussion was desired by those present. Prof. Schiff desired information as to which micro-organisms were examined. Mr. Vilter, who being a machine builder, was not in position to give information on this point, the Chairman advised the questioner to communicate with Dr. Smith directly. Prof. Els ching, who had announced a paper for this sitting, not being present, Prof. Schiff was requested to read his paper on "The a pp 1 i cation of cold in the treat m ent of skin a ffection Sº. (See p. 49.) * wº At the close of the lecture Prof. Suida, who had meanwhile taken the chair, thanked the speaker, and no one raising any question, and Prof. Kas do r f and Prof. Bail, whose papers were also announced for this sitting not being present, asked Oberstabsarzt Dr. Sick in ger to deliver his paper on "The use of cold in de n tistry. (See p. 52.) - As no question was raised in response to this paper, the Chairman thanked the speaker for his interesting statements and requested Herr Prof. Kirsch to give his paper on Tests on the hardening processes of hydraulic cements at low temperatures. (See p. 54.) At the close of this lecture which was followed with the greatest interest, especially by the technicists present, the chairman asked the meeting if anyone desired to make any statement. There being no response, he thanked the speaker, and then explained that the other papers on the day's programme could not be read owing tho the absence of the lecturers. He then gave permission o Herr Prof. Dr. Kamerlingh - On nes to make a statement to those taking part on the Congress. Mr. Kamerlingh-Onnes: We had intended on the very first day to make a statement concerning the work of the Ist Commission > On refri- geration units& ; it was impossible to do so, however, owing to various interruptions. Nor could the report in this connection be distributed among those taking part of the Commission, though I succeeded after much 70 trouble in securing a copy. It deals with an exchange of ideas between Barrier (France), I. De war (England), Cl, Ed. Guillaume (Switzerland), Kamer lingh-O n n e s (Holland) and Mollier (Germany), Guillaume acting as reporter. The object was to set the matter in motion and to prepare a preliminary report as basis for the work of the Commission in order that further decisions might then be formed in a conference to be called by the Commission. So far but 25 copies of this report • Les Unités de l’Industrie du Froids are at hand, by to-morrow, however, it will be possible to furnish each of the gentlemen with a copy. - Geheimrat Mollier, who had in the meantime again taken the chair, stated that Prof. Dr. Doelter, whose paper was announced for this sitting, was unfortunately prevented from attending, and he therefore closed the sitting with an invitation to participate in the inspection of the *Hygienic Institute of the xUniversity of Vienna & and the Institute for General and Experimental Pathology*, on the following day, and with the information that the next sitting would be held on Monday, October 10* at 10 a. m., at which Prof. Dr. Kamerlingh-Onnes would speak. The papers of Prof. Dr. Elsching, Dr. Lorenz, Kasdorf, Dr. Bail, Hofrat Dr. Neu- wirth, Prof. Simony and Prof. Dr. Artmann were also announced for that sitting. 3* Sitting, Io" October, 1910. The Sitting began at 10 a. m. and lasted until 12:30 p.m. Honorary Presidents: Ing. G. Claude and Prof. Dr. Kamerlingh- Onnes, Vice-President: Prof. Dr. W. Suida, Secretary: Dr. A. Skrabal. Geheimrat Mollier opened the sitting at 10 a. m. and proposed that Ing. G. Claude be chosen as chairman. (Loud applause.) Ing. Claude accepting the chair greeted the meeting speaking in French. He referred to the necessity of combined action of theory and practice. He pointed out the debt owed to Kamerlingh-Onnes (who a short time previously had succeeded in reaching the absolute temperature of + 3°) as regarded the theory of the problem of refrigeration, and drew attention to the progress that had been made in the Refrigerating industry through the work of Prof. v. Linde. Progress in the paths opened up permitted the final solution of the problem of refrigeration to be confidently expected. (Long continued applause.) The chairman then asked Prof. Kamerlingh-Onnes (Leyden) to give his paper on >The question of refrigeration units.<. Prof. Kamerlingh-Onnes began in French and then continued in German: I take the liberty to inform you of the state of the work of the commission for refrigeration units. A preliminary report lies before you • Les Unités de l’Industrie du Froids of the Commission for refrigeration 71 units. This has the character of a proof impression intended to circulate among the members of the Commission, that these might add any corrections they desired, including typographical errors. It was found necessary to submit a project that took into account everything that was connected with the question. In order to meet all resulting difficulties we drew up a preli- minary report. This, it was intended, should circulate among the gentlemen of the international Commission that they might make criticisms thereof. We hoped at least to be able to submit this work here. I regret to say that we have been unable to do so. There had first to appear a proof copy of the preliminary report, which would be laid before you. I may also add, that it has met with complete approval from the individual members of the Commission. I would like to express the wish that if you judge the work favourably, and do not take umbrage at the delay, you will require the international Commission to continue the work in the same manner. I beg you, gentlemen, not to trouble about the time the matter takes, but only to ask yourselves whether we gain any end and achieve anythings. (Loud and continued applause.) Prof. Kamerlingh-Onnes continuing said: I take it from your applause that you agree with my prºposal. There is another formal matter still waiting Settlement. An international Commission is a very awkward apparatus. We have just seen that progress is only possible, if we divide the work between us. This has led to the formation of sub-commissions, namely, a biological, a physical-chemical, and one for the units. I request you, gentlemen, also to approve this division of labour already undertaken. Finally I would like to settle a debt of gratitude we owe to M. Guillaume, who has supported us in our task by self-sacrificing work. As M. Guillaume is hindered by ill health from being present at our discussions I would like to suggest that our thanks be telegraphically communicated to him. (Applause and clapping of hands.) Chairman: The gentlemen have heard the suggestion of Professor Kamerlingh-On nes. If no objection is raised (pause), I declare the same accepted. (Cheers.) I now request Prof. Kamer ling h-O n n e s to give the paper announced by him on the operations of the cryogenal laboratory at Leyden. Paper by Prof. Kamerlingh-Onnes: • Experiments at the cry - ogen a 1 Lab or a to r y at Ley dens. (See p. 19.) After the lecture, which was received with lively applause and illustrated by limelight diagrams, Prof. Verschaffelt requested permission to speak, and put forward the following statement, in his own name and in the names of Messrs. C1 a u d e (France), M o 11 i er (Germany), Sui da and H as en 3 hr 1 (Austria): The I* Commission of the II. International Congress of Refrigeration in Vienna expresses the desire that the International Association of Refrigeration may suitably support the examinations of Pro- 72 fessor Kam er ling h - On nes, the epoch-making importance of which is so entirely beyond all doubt. (Applause.) Herr Geheimrat v. Linde: I believe that to this proposal, with which we all heartily agree, we should not reply shortly: = yes<. It seems to me to be necessary that we add a special word here to what we have heard. Our Congresses of Refrigeration would miss the connection with their own foundations if the representatives of the pure sciences did not take part in the work of the Congress. It is therefore of the greatest value to us that, at the present time, the most important and most successful experimentist in the sphere of low temperatures has furnished us with an insight into these labours which require so great a degree of penetration, patience, perseverance and understanding. I therefore think that we shall all agree emphatically, if the International Association support the work of Prof. K a m er ling h- O n n e s out of the means accruing to it. Herein we should see one of the most valuable services that it is in the power of the Association to render. (Long, continued applause and expressions of agreement.) Prof. Kamerlingh-Onnes: I must express my thanks for the friendly words with which our work is remembered. I have conceived the assistance that should be offered to our Institute in such a manner that a protective committee be formed, to which, under the presidency of Prof. van der Wa als, Messrs. Ca il 1 et e t, Dew a r, v. L. in d e and Olszewski belong. If my dream, that these gentlemen would accept the curatorship of the subsidies granted, could be realised, it would be matter for great pleasure and satisfaction to me. (Cheers.) † * Chairman: I now request those gentlemen who are in favour of the proposal of Versch a f felt to signify this by raising their hands. (This is done.) I ask for the counter test. (After a pause.) The proposal is unanimously accepted. I now re quest Prof. Kamer 1 in g h - O n n e s to take the Chair. (Done.) Chairman: Are Messrs. E 1 s ch i ng, K as d or f and Bail present? They are not here. Then I request Mr. Lorenz to give the paper annouced in his name. -- Primararzt Dr. H. Lorenz: *The app lic at i ö n of coºl d in surgery. (See p. 42) Chairman: Does any gentleman desire to say anything? This not. being the case, I would like myself to put a question to the speaker. At the request of some Dutch physicians I placed this distilled carbonic acid at their disposal, which does not exhibit the disadvantages that result from the use of the ordinary carbonic acid. I would like to ask if the speaker has collected any information in this matter. Dr. H. Lorenz: In using ordinary carbonic acid I have so far not been able to discover the disadvantages mentioned. - 73 Chairman: Thank you. Are Prof. Simony and Prof. Artmann here? It seems not. Then I ask Hofrat Dr. Neuwirth to give his lecture. Hofrat Prof. Dr. Neuwirth: "Cold a s a n e n e my to the pre - servation of m on u m en ts.< (See p. 59.) In the course of his statements the speaker urged that the next inter- national Congress of Refrigeration should thoroughly discuss the theme: >Protection and preservation of monuments and public buildings.< (Cheers.) Chairman: Does anyone wish to raise any point? This seems not to be the case. Our programme for the day is hereby finished. I thank all the speakers for their information and close the meetings of the I* Commission. COMMISSION II. Constructing, Operating and Testing Refrigerating Machinery wº and Insulating Material. 77 What are we to Understand by the Term ,The Efficiency of a Refrigerating Machine?" By Alexander Satkewitsch, Professor at the Academy of Engineering at St. Petersburgh. The endeavour to place the question of the production of low tem- peratures upon a strictly scientific basis makes it necessary to work out the general theory of refrigerating processes exactly and to fix most carefully the fundamental conceptions and representations. If the rather limited and purely formal question regarding the determination of the term the 'effi- ciency of a refrigerating machine& has no immediate practical significance, it must yet be taken into account when working out the fundamental conceptions concerning the reduction of temperature, because it leads to ambiguities and differences of opinion. For this reason I beg your attention to a discussion of what must be understood by the efficiency of a refrige- rating machine. In my further remarks, for the sake of brevity, I shall only .” consider machines of the compression type. - If we analyse the question put, we must in the first place be clear as to what the economical efficiency of an apparatus really is. It is well known that this expression is employed to represent the proportion of the useful effect to the general total of the gross expenditure for the operation of the whole apparatus. Evidently this coefficient is always more than zero, for both numerator and denominator of this proportion are essentially positive values. As our belief in the principle of the conservation of energy leads us to the conviction that in nature nothing happens without cause, i. e., that the result never exceeds the expenditure, and in consequence of con- tingent losses is often less, then the efficiency cannot exceed the maximum effect of a given force. Now let us pass to refrigerating machines. . At present there exist two different distinguishing characteristics of the conception efficiency of a refrigerating machines. The first conception (see for example the article by Schrötter and Prandtl, XTechnical Thermodynamicss, in the "Enzyklopädie der mathe- matischen Wissenschaften vol. V. Physics, I, 1905, p. 286; the article by 78 Linde in x Lueger's Lexicon d. ges. Techniks, Is' edition., vol. V., p. 353; L. Marchis, 'Production et utilisation du froids, 1906, p. 70 etc.) defines >efficiency of a refrigerating machine « as the proportion of the energy of heat withdrawn from the body to be cooled to the mechanical work expended in the operation, both energies being expressed in the same terms. Here, apparently, a fundamentally correct idea is taken; the useful effect achieved — cooling — is compared with the amount of mechanical work expended for it. The apparent accuracy of the idea is however based upon a misconception. The fundamental process of a refrigerating machine is not the transformation between heat and work, but the latter is merely employed for transferring the heat from its source, the brine of low tem- perature to the cooling water of higher temperature, in a word, to pump the heat from a lower to a higher heat level. The work expended is only the compensating addition to the transferred heat, which serves for the process of transfer. We will call to our aid here an analogy that, though it be not quite exact, yet will to a certain extent illustrate our views as stated. Suppose we have two weights A and B suspended from the ends of a string passing over two or more pulleys. Suppose further that these weights are equal and at rest. Let us now add a force, for instance, to B, then A will rise. We allow it to rise for a time till it reaches a point H. The raising of the weight A to the height H above its original position is shown by the work AH, which for short we will call L. Would it be correct, in order to calculate the economy of such a lifting apparatus, to divide the work L. by the work I of the additional force : The useful effect, it is true, is the work L, and the expenditure the work I; could then the proportion L/I really characterise the economy 2 Now, however, we reckon the work L in lifting at the expense of the sinking of B, which exerts a corresponding amount of work. The additional work I is only expended overcoming friction, stiffness of the string, momentum of the bodies, etc. In such a lifting machine the weights of A and B can be changed, when several factors; e. g. stiffness of the cord, amount of additional work increase unproportionately. The speed at which the weights move also has an effect upon the amount of additional work. Moreover, in such a calculation the efficiency of the apparatus will almost always be greater than unity, and the value of this figure will never be definite enough to enable one to judge of the advantages of the mechanism. We find the same conditions in refrigerating machines. The heat abstracted from the brine plus the thermal equivalent of the exterior work done is transferred to the cooling water. In the above described lifting mechanism, it is true, that the quantity of additional work depends almost entirely upon the perfection of the mechanism, for to a great extent it is expended upon the so-called harmful resistance and, by a very slow raising of the weight A, may be very slight. In refrigerating machines, on the 79 other hand, the expenditure of work cannot be less than is represented by the difference in the temperatures of the cooling water and the brine. This, however, does not change the essential part of our explanations Here, too, the efficiency generally amounts to more than unity. Actually, if the refri- gerating machine develops, say 4000 cal. per hour for every h. p. of work expended (the cooling effect is in reality often higher), then we find (remem- bering that 1 h. p., which is equal to 75 mkgr. per sec., furnishes within an hour 75X3600 = 270,000 mkgr. of work or * — cal), that the proportion which characterises the economy of the machine is equal to 4000:632 or 6.33. What does the figure 6.33 tell us? How near is the machine to perfection ? The calculated characteristic does not contain direct proof of this. Is that then the efficiency? Some authors, among them Linde, do not describe this proportion as seconom. efficiency «, but give it the special designation • Leistungsverhältniss proportion of effect of the machine. But what difference does this make? After the above remarks we can quite understand the desirability of seeking another expression for the conception of the efficiency of a refri- gerating machine. If in the economical efficiency we seek the expression of the degree of relation between a certain construction and its in principle perfect conception, then we must be clear as to what is to be considered a perfect expression of this conception. In this respect the thermo-dynamic theory of heat motors serves as example. It proves that of all possible circular processes with bodies the most suitable for the production of mechanical energy is the so-called Car not cycle, a closed cycle in which heat is taken from a source having a constant temperature, and the heat unchanged is led to another source also with a constant, though lower temperature. In order that the Carnot cycle may be ideal, the fulfilment of the condition that it be reversible is imperative, that is, there must be no unrecoverable losses in the complete cycle. The example of thermo-dynamics leads the theorist in refrigeration matters to prove that the Carnot cycle is also the most advantageous for cooling operations, and to characterise the economy of every circular process by the coeffiicient which represents the proportion of the exterior work that must be done by the cooling machine to the work expended in the operation of the machine. (See G. Zeuner — »Techn. Thermodynamikº, 3. Aufl. 1906, Vol. II, p. 457; M. Leblanc — »Rapport au 19* Congrès du Froid a Paris& — Résumés en franc. des rapports déposés au Secr. av. le 28 Août 1908, p. 40–80.) The efficiency attained would actually not exceed unity and by its nearness to 1 would characterise in conception the degree of perfection of the circular process of the refrigerating machine, if the conviction that the Carnot circuit is really the most advantageous were completely demon- strated. But is this the case? = 632 units of heat 80 Momentarily it may appear erroneous. And in fact if the reversible Carnot cycle is the most advantageous for converting heat into work, it means that it furnishes the greatest amount of work with the addition of a certain amount of heat in the heat engine. It follows therefore that the fullest realisation of the cooling operation, for a certain amount of useful cooling, must require the greatest amount of mechanical work, i. e. must be the least advantageous of the reversible cycles. What support then have the proofs of the advantages in principle of the Carnot cycle for the refrigerating machine If we refer to any treatise on refrigeration matters, e. g., J. A. Ewing — »The mechanical production of colds (German translation by Banfield, 1910, p. 6–8) we find something like the following: *Between two sources of heat with constant temperatures. — the one with a higher temperature T (absol.), the other with a lower temperature To -— two mechanisms are simultaneously working, heat motor and refrigerating machine (heat pump), and in such a manner that the latter uses up the whole of the energy produced by the former. Presumed that the motor executes the convertible Carnot circuit. If the refrigerating machine as regards cooling admitted of more ideal construction than the motor, i. e., so that it absorbed more heat from the source with tempera- ture T, to be cooled than was imported to it in power by the motor, then the result would merely be the transferrence of the heat from the source with lower temperature To to the source with higher temperature T. & Such a mechanism would be contradictory in idea of the present principles of thermo-dynamics. Thus the Carnot cycle is the most advantageous for refrigerating operations. That is the scheme of the argument. But it might also be possible to prove in this manner that the cycle of the refrigerating machine cannot be more ideal than any chosen cycle of the motor! Is this actually the case ? The reason for this hasty inference must be sought in the argument itself. This gives but two sources of heat with constant temperatures and compares the Carnot cycle with any other produced between the two sources. But what process of a type other than the Carnot can be imagined, if the exchange of heat is only possible at the two temperatures T and To It is therefore evident that in this manner only the equal values of two Carnot cycles between two sources of definite constant temperatures can be determined. The reasoning as regards the advantageous result with the Carnot process for refrigerating machines is, however, in some respects well founded. To explain this circumstance we will first determine the relative useful effect of the Carnot cycle for heat motors. Thermo-dynamics shows that the economy of the change of heat into work is greatest the farthest the supply and delivery of heat are separated (the higher the temperature T of the heater and the lower the temperature To of the refrigerant). If we bear this in mind we easily arrive at the conclusion that in the comparison of any cycle which at changing temperatures absorbs and gives off heat, with the Carnot cycle, which 81 receives the whole of the heat at the highest temperature that occurs in the circuit and gives off the remainder at the lowest temperature produced by the circuit, we easily arrive at the conviction that the Carnot cycle must without doubt be the most advantageous. If, however, the Carnot cycle were such that it received the heat at the lowest temperature and gave it off at the highest temperature, it would certainly be less advan- tageous for the motor than the given circuit. Finally a comparison of the circuit with the Carnot cycle, the central one of the two above men- tioned may incline either to the advantage of the latter or of the circuit given, according as the limits of temperatures of the Carnot cycle are separated. The same is applicable, however, in the contrary sense in respect of refrigerating machines. A refrigerating machine uses up as much more mechanical power as the limits of transmission of heat are farther apart i. e., the higher the temperature T and the lower the temperature To. It is therefore of advantage in increasing the economy of a refrigerating machine that the maximum and minimum temperatures in the cycle be brought closer together. Consequently any cycle of a refrigerating machine will be less advantageous than the Carnot that possesses a constant temperature, To, of the heat absorbed, the highest of all temperatures applicable in the given circuit and a constant heat supply temperature T, the lowest that occurs in the circuit (Cp. Ewing "The mechanical production of colds. German transl., p. 8, line 9 – 5 from the bottom). Those are the conditions under which the Carnot circuit is the most advantageous. * If, however, the brine to be cooled by the refrigerating machine changes its temperature by giving off heat and this be also the case with the cooling water during the absorption of heat, then the question arises, why should the Carnot circuit, with constant brine temperature equal to its highest original temperature, be considered ideal for such a machine * In practice the lowest final temperature of the brine is surely of impor- tance P Would it, then, not be more correct to construct the Carnot cycle for some average of the brine temperature ? But in this case its advan- tages would be doubtful. From these details it becomes clear that in forming an ideal cycle of a refrigerating machine we must also consider whether the Carnot cycle can be considered as such ideal cycle. It is in fact maintained in many quarters that the Carnot cycle is not ideal for a refrigerating machine. (See article by Linde in Lueger's ‘Lex. d. ges. Technikº, V, 1. Aufl., p. 353). If we now return to the task of characterising the economical efficiency of a refrigerating machine as a proportion between the energy expended in equally productive circular processes — the Carnot and that supposed — under certain fundamental conditions of the cooling, we shall scarcely be in a position to consider such definition as sufficiently sound. The lack of evidence makes us demand stricter proofs. If, further, we seek to estimate 6 82 the economy of a refrigerating machine by comparing its cycle with that of Carnot, we make other demands of it than of the heat motor, since the economy efficiency of the latter is not only calculated in proportion to the corresponding Carnot cycle but its economy is also taken into account. Therefore in such a definition the numerical significance of the economical efficiency for a refrigerating machine must be understood differently in principle from that for a motor. According to the above statements we must ask ourselves the question if we cannot define the conception > economic efficiency of a refrigerating machine & avoiding the above difficulties. For this purpose we will consider the following. As the effective process of a refrigerating machine in which the transmission of heat from one source to the other is effected by mechanical power, then its greatest economy corresponds to the work L, which is equal to zero, when the economical efficiency of the cycle, as above mentioned, must change to a unit. We will express this thus: (m) L – o = 1 (the economic efficiency we express by the Greek letter m). This condition is fulfilled if the denominator of the fraction that expresses the economic efficiency differs from the numerator only by an L as addition containing the multiplier. As m connot exceed a unit this addition can be taken either as a decrease of the numerator or as an increase of the denominator. Otherwise the economical efficiency of a refrigerating machine at infinitely greater expense of energy L must become zero, i. e., (m) L = 00 = O. This last requirement shows that the addition must be to the denominator, thus in the shape of an addition. If now it is desired that the numerator represent a useful effect of the cooling, i. e., the heat abstracted from the brine, which we will express by Qo, then it is simpler and more natural to express m by the fraction 7 = oº::=% A representing the thermal equivalent of work (I: mechanical equivalent of heat) and Q the whole of the heat transmitted to the source of higher temperatures, i. e., cooling water. The efficiency obtained in this manner, and applied for the reversible Carnot circuit, acting between the temperatures T and To, receives the form m = }=} for this cycle, in consequence of the mutual proportionality of the values Q and T. From this formula the advantage of an approach of the temperatures To and T, for the increase of the value m up to a unit, is clearly evident. For the above case, taken as example — consumption by the refrigerating machine of 1 L. p. per 4000 units of cold per second — the economic efficiency of the proposed type assumes the numerical significance of: 'Y) = 4000 | Ti 4000 + 632 I therefore beg, referring to the above statements, to propose: That the theoretical economy of the cycle of a refrigerating machine be estimated = 0,86. 83 at the efficiency represented by the proportion of the quantity of heat abstracted from the brine to the quantity imported during the same period of time to the cooling water, or air, or both. Finally I would like to remark once more that I do not attach any particularly practical importance to the presence of the conception of the theoretical efficiency of the refrigerating machine. But if now, with the endeavour to form a normal characteristic for refrigerating machines, it should be considered to be necessary to retain this conception, then in my opinion it is absolutely necessary to formulate it with the utmost exacti- tude. In that case, perhaps, my ideas here expressed may be of service. 6% 84 The Electrical Telegraphic Thermometer. By Ingenieur Johannes Rautenkrantz-Wien. In every rationally conducted Refrigerating Plant a constant control of the temperature is absolutely necessary. There are certain disadvantages in the way of undertaking this with ordinary quicksilver thermometers. It is necessary, namely, to enter the particular room in order to ascertain its temperature, and there is also an absence of practical constructions of such quicksilver thermometers as continuously and automatically mark the tem- peratures. A modern plant for taking the temperatures of a cold house must satisfy these conditions. It must be possible, in the first place, to take the temperature of a room without having to enter the room, in order that time may not be lost; and sometimes, in meat cold storages, misunderstan- dings would also thereby be avoided between authorities and butchers. Further, taking the control of the workmen into consideration and as voucher for any possible claims, it is advisable that the temperatures should be constantly recorded by the apparatus. Both of these requirements are fulfilled by the Siemens & Halske, A-G. electrical telegraphic thermometers. This method of taking the temperature is based on the change of resistance of most metals according to the temperature. The arrangement makes use of the Wheatstone Bridge switch in which three arms are made of a material free from temperature coefficients, whilst the fourth arm has the so-called “resistance element». In the system of resistance ther- mometers under consideration this “resistance element” consists of a thin platinum spiral which, for protection against external mechanical and chemical influences, is completely melted into a little stick of quartz. It is just the use of two such indifferent materials as platinum and quartz that makes this method of measuring the temperatures suitable for such various purposes. This quartz-glass resistance element is made by Messrs W. C. Heraens, at Hanau after their own patents. Fig. 1 shows a resistance element as used to measure the temperature in living rooms, store rooms, cold rooms or any other rooms. For pro- tection the quartz stick containing the platinum spiral is encased in a perforated metal coat. A small ordinary quick- silver thermometer is, in the latest models, affixed to this metal protection thereby enabling everyone to read off the temperature of the room on the resistance element itself. Fig. 2 shows an armoured resistance element such as comes into consideration for the measurement of gases or liquids under pressure. Either copper or steel tubing is used in armouring according to the objective use. This kind is used, for example, in keeping control over the temperature of cold liquids, it being screwed into the piping. The switching of the recording apparatus is shown schematically in Fig. 3. I, II and III are the arms made of resistants, free from temperature coefficients, in the fourth arm just such another resistant, the trial resistant, can be switched on by pressing the knob A. It serves to keep the tension at the points a and b con- stant. This takes place through the little regulating resistant RW in such a manner that the galvanometer G is set at a special value, for instance at end-beat. If the tension at disposal at E is not con- stant but sinks in the course of time, as in the case of a primary or secon- dary element, this regulation must take place at certain intervals. By pressing Fig. 2. Fig. 3. knob B, the resistance element WE is then switched into the bridge arm, whereupon, the galvanometer being graded in Centigrade degrees, the tem- perature to which the resistance element is exposed will be immediately recorded, w is a small adjusting resistant which serves to equalize the resistance of the changing lengths of service pipes. By duplicating knob B | it is possible, of course, to connect as many resistance elements as desired - with the measuring apparatus. Fig. 4 shows such a recording apparatus for 60 points. Considering the mounting of the apparatus and the grading of the galvanometer, it is necessary, of course, that the resistance elements be all 86 - - electrically equal; ) such is the case with the above described quartz- glass platinum spiral, so that the physical and technical Reichsanstalt Fig. 4. Telegraphic temperature recorder with switches for 60 points of measurement (executed for a Wolksschule). (Imperial institute) could express readiness to certify the tempe- ratureS. *) The equalisation of the resistance elements with each other takes place with an exactitude of 0.04 per cent of their resistance values, so that the absolute exactitude when 50 ohms resistance elements are employed is accordingly '2" Centigrade. - _- - - - 87 The separate resistance elements can, naturally, be placed at any desired distance from the recording apparatus. Seeing that copper is used for connection work and that copper has a fairly high temperature coefficient, the dimensioning depends on the changes that take place in the resistance of the platinum spiral, the variations of temperature that the connection work is exposed to and the degree of measurement exactitude demanded. If, for instance, the scale reaches from –15° to +25°. C., that is compasses a measurement of 40° C., and given resistance elements with platinum Fig. 5. spirals of a resistance = 50 ohms at 0° C., whose resistance at 5° C. changes nearly 1 ohm, then a 40" C. change of temperature would mean a change in resistance of 8 ohms. If the copper wires, in consequence of misplacement, are liable to changes of temperature of 0° to 20", i. e., ± 10° C. of the medium temperature, and if the error may not exceed 1 per cent of the - 1 measurement compass, then only a change of resistance of -º- 8 =008 ohm is permissible in the connection wires. It is known that copper changes its resistance 0.4 per cent for a temperature change of 1" C., therefore 4 per 88 cent for 10°, and consequently the resistance of the connection work may 100 - - . . . . . . " amount to O'08 . 4 section a distance of about 85 metres (93 yds), and with section 2.59 mm. (0.102 in), 140 metres (153*h, yds). With telegraphic thermometer apparatuses for higher measurement compasses, these distances can be considerably in- creased given the same percentage exactitude and supposing the same tem- perature variations. As the connecting wires are generally in walls or in tubes, their variations of temperature are generally Smaller; the distance for the same percentage exactitude can be increased in consideration of this fact, or the section of wire decreased. For greater distances either the section must be comparatively increased, or the amount of copper required may be reduced by laying three wires instead of two for each resistance = 2 ohms, which means with a wire of 1.59 mm. sº element. The changes in resistance of the connection work then, with Suitable Switching, balance each other's effect. The switch knobs on the measurement board are so constructed that the previous knob is automatically freed when the next one is pressed, thus preventing two resistance elements from being switched on at the same In Oment. - - The galvanometer is a turning spool instrument after the Deprez- d'Arsonval system with scale almost in proportion. As source of current one or two dry or bottle elements are used; accumulators may also be - used. The current required by this telegraphic thermometer apparatus is exceedingly small (about 'ligo Ampère), so that a dry element or an accu- mulator suffices for several months. - . If it is required to record the temperatures continuously, then tempe- rature measurement boards with registering apparatus come under conside- 89 ration. Fig. 5 shows such an apparatus for two measurement points in the new swine slaughter-house of the municipality of Vienna. In such plants each resistance element has a separate registering galvanometer. For Small º | | É is: measurement compasses, such as occur in refrigeration technics, use is made of the registration apparatus that has come to knowledge through the thermo electrical Pyrometers. The electric force acting on the catches of the galvanometer through the resistance change of the platinum according to the temperature is too slight to make it possible to allow the hand to 90 continually rest on the paper strip. The recording takes place in such a manner that a trigger worked by the clockwork of the apparatus sinks at certain intervals of time on to the hand and presses the knob attached to the end of this firmly down upon the paper strip. In order to make the position of the hand known by means of a distinct point, a ribbon or carbon paper is placed under the registration paper strip. The various points form a continuous, distinct curve. Fig. 6 shows such an apparatus with paper strip coming off. Fig. 7 shows the instrument with raised hood. The paper strip of 45 metres length unrolls as required at 20 mm or 60 mm per hour. The fall of the trigger takes place every 60 or every 15 seconds. - - ^. - Figs. 8 and 9 show a registering apparatus in which the paper strip and blue paper are placed round a drum and must be replaced after each turn of the drum, that is in about 24 hours or in 7 days. The recording Fig. 9. by means of the trigger takes place in correspondence with the rate of movement of the paper once in every 2 minutes or every 12 minutes. The clockwork may be set for both speeds. In many cases with such apparatuses it has proved advantageous to affix an adjustable minimum or maximum contact regulator. The sinking trigger is then ingeniously used in forming the contact. By means of this arrangement optical and acoustical signals can be given, or with the help of suitable relais regulating mechanism, motors etc. may be put into or out of gear, so that under certain conditions for instance the setting of the refrigerating machines in work can be auto- matically done. ^. . 91 INVESTIGATIONS AS TO THE EFFICIENCY OF AMMONIA COMPRESSORS WHEN RUNNING : UNDER DRY AND WET CONDITIONS. -- Also Operation of Ammonia Condensers of Dry and Wet Systems. By THOMAS SHIPLEY, Vice-President and General Manager, York Manufacturing Company, York, Pa., U. S. A. Before proceeding to give the results of the investigations made under his direction upon the above subject, the author believes it would be well to set forth what he understands to be the accepted definition of “Dry” and “Wet” conditions,—the more especially as it was upon this basis the investigations referred to herein were made. *. - By “Dry Conditions” we mean that the Ammonia Gas entering the Compressor will be slightly superheated. By “Wet Condition” we mean that the Ammonia Gas entering the Compressor will be accompanied by sufficient liquid to absorb the heat of compression so that the temperature of the discharge will be that at which ammonia gas will condense under the pressure to which it has been compressed. The question as to whether a compressor will do more work operating under the “Dry Condition” than it will when operating under the “Wet Condition” was long an open one in the United States, the advocates of the “Wet Condition” claiming that compres- sors operated under the “Wet Condition” would produce a ton of refrigeration for less power, and that less water would be needed to condense the ammonia than the same compressor would require if it were operating under the “Dry Condition”, the authority for this claim being based upon advice said to have been received from certain European experts. In the absence of data to prove or disprove this claim, it became almost the universal practice in the United States to operate Hori- zontal Double Acting Compressor, especially, those having spherical 92 heads, under the “Wet Condition, and all other compressors, especially Vertical Single Acting Compressors under the “Dry Condition.” This was because the principal advocates of the “Wet Condi- tion” were builders of the Horizontal Spherical Head Double Acting Compressor, while the principal advocates of the “Dry Condition” were builders of the Vertical Single Acting Compressors. The York Manufacturing Company, of York, Pa., U. S. A., with whom the author is connected, determined to investigate among other things, the efficiency of , ammonia compressors, both of the Horizontal Double Acting Type and the Vertical Single Acting Type (both types of which they build). These investigations were to include operation under all practical conditions,—especially “Wet Condition” and “Dry Condition.” - To this end they enlarged and reconstructed an experimental plant they had at their works at York, Pa., and proceeded to operate same for the purpose of these investigations. This work was con- ducted under the direction of the Author. The plant was operated from July, 1903, until January, 1907, during which “ - about one thousand (1000) runs were made, averaging about seven and one-half (7%) hours each, Over five hundred (500) of these runs have been averaged up and classified. The data obtained from the runs made to determine the relative efficiency between operating a compressor under “Wet” and “Dry Conditions”, proved conclusively that, a compressor run under “Dry Conditions” requires less power, and less water for ammonia condensing, and for compressor cooling (when jacket water is used for this pur- pose) per ton of refrigeration than it does when the same compressor is run under “Wet Condition,” and further, that the capacity of a com- pressor is materially decreased when run under “Wet Condition.” These facts were found to be true regardless of the design or type of the compressor. -. These investigations also brought out the fact that when an Evaporating System was operated" so that the ammonia gas leaving it would be superheated as was the practice in the United States prior to these investigations where the compressor was operated un- der “Dry Conditions”, the evaporating system was much less effec- tive than it was when the gas leaving the Evaporating System car- ried liquid ammonia with it, as was the usual practice when the com- pressor was operated under “Wet Conditions.” . . - 3 The obvious reason for this difference in efficiency being that in the latter case the liquid ammonia flooding through the system ---- |-----· ： （ ） | （ | |-|-|- （~~~~（~~~~ | | ** 94 kept all the surface wet, whereas in the straight “Dry” Compres- sion Plant the evaporating surface was only partially wet, and was, therefore, less effective. - - Thus on plants in which the compressor was operated under “Wet Conditions”, the loss of compressor efficiency was counter- acted to a certain extent by the increased efficiency of the Evaporat- ing System. This fact explains why. “Wet Condition” plants kept their footing in the market so long. To correct this loss of efficiency of the Evaporating Surface un- der the “Dry Condition” the author has introduced a separator or trap between the evaporating system and the compressor. This trap Separates the liquid ammonia from the gas, returning the liquid to the evaporating system, while the gas passes on to the compressor. Connected up in this manner, both the compressor and evaporating system can be operated under the most efficient condition. This sys- tem is now known in the United States as the Flooded System. The results of these investigations have been the breaking down of the claims set up by the “Wet Condition” advocates, most of whom now advocate the “Dry Condition” of operation, and many plants which did not come up to the guarantee under the “Wet Con- dition” of operation have more than filled the guarantee under the “Dry Condition.” . The following data give some of the results of the investigations referred to. The results given are taken from two of the series of runs, made with the Double Acting Compressor. This is the type of compressor which was said to be more efficient when operated under “Wet Conditions” than under “Dry Conditions.” (Experiments made with the Single Acting Compressor showed the same relative efficiency of “Dry” over “Wet Conditions” of operation.) Series XX.-This series was run to determine what the result would be when the discharge temperature was increased from that. due to “Wet Condition” to the highest obtainable discharge tem- perature under “Dry Condition” at the pressures and speed. This series was run under three Suction or Evaporating Pres- sures,-these pressures being those which are generally used, the first (5 lbs.) for Freezing Rooms, the second (15.67 lbs.) for Ice Making, and the third (25 lbs.) for Breweries, Packing Houses and Cold Storages. - The condensing pressure was held at 185 lbs. above atmosphere and the revolutions of the compressor kept at 60. Attention is called to the substantial increase in tonnage, the de- crease in horse power per ton of refrigeration and the decrease in the amount of water needed as the temperature of the discharge raises, especially under the lower Suction Pressures. Za Z, Ze AZo. Z. Frezza series XX ºf York Mazzºyacázz-irºz co-eeza. --52's Zveze. Ive: zºez'szzs 22% 22era ºozz 2/*-īzzzzzzozzia. Cezzzaressez-. 42# ‘x13'224. Hozºzozzá22 cozzzzz-essor. cºzzecz cozzzzeczecz zzz 22 zz- cºezzz #o 45 ° x 13” Jºſe rzz ozz #22 Caz-Zzss 5 #e a zzz **** ***e. ^ .# § º § {\ } . . . R; 1. eage fºr #e; º tº e º $| || ; : § 0 § , QY Q § #. §§ § ; § x * #| || | | | | | | | S j §§ ##| || || 5 || St § { § §§ | * : . . . ; * | $5 |&S # 5 $ #3 || 3% § is $$ | | | | | | \{ || || ||Y}} | {{ | | | | | R. 3 j : $# | #| | | | | | | #| | | | | 3 |: ; ; § & | | | | $6 || 3 | tº $ ºš |$$$ $ 5, i & || "S$ d; .# S Q; S &; R, 5 || $ "|\ S. tº 333 gzz-Tazza Taala Tsz = Tsaa Taala-TazzTzza TF 7: Tasſa § J 4.2 © . 2 5 /83. oz © / . J. / OO .. 7 © . Sº O © 2 - 7 O 4 - 7s 7 / ... O 2. / / 4. S. 35 t; J. 2 «S Jº . 8 O /34 . / O © O - 2 2 / Jº 7 & . .3 O < 7 . & C 2d . O& 73 - O A - 7& 33 - A Q JJ 4. 5. 7 O | A & 23 . 743 & O . Ç 29.4: . 2 | f 3 - 3 & 1 2 3 - 85 || 2 - 2 O || 72 ... O / - Oc 24: .. 8 {{Tage 5.os 184.so a o. 1 sos. o 17. as 2 a.2e 2 . of 7 / .3 o. s.7 23. , § J J 2 J. & S | f 34. . $2.5 || 3 / . & 32 O - 3 | f S. 55 || 23 . Sº O / . Sº 3 || 33 - / C - 5& 22. 7 + Q} | * 33 o /JG , 7 / | f 84 - 5 O || 6 O. 2 3.4: ... & | f 2. 3 O }ce:czz ZYo. 2 F- 25zºzze CZ 7°2 &4/2/3 ozº Coža. Az-zzze = Pyarzzz º > Sãeazz 3-3 * * * * * * * * * * H —o rak f ſº r—s Cola, Arizze Aarºz Azine Coo'ez’ \ in-l -5 rārae 73 raž Tº z-A- Zºg. Co. Yoz-At. Fa. ! 103 culated through an exchanger, thereby heating the brine in the other circuit, which was in turn circulated through the brine coolers, where it evaporated the liquid ammonia fed into the ammonia spaces of the coolers. With this system it was found that a very even condition could be maintained. 4. Jºžešcº. -ZVo. 3 Ca2222*a*zazz 27 -5'2"zzze A*zzzzzzº Swizzºzzz3 Jaozze w 42&czz*zc Cozzzzfez’ Joazes S=U=T | | i i ! * E * - - - - sº - - * - - - - - - - - = ==== TE AH º *- :- - - - - T - º **assye ºzºzº: T 25ºze. Fºrge Yozºr AZ33. Co., Yozºr, Fºx. 104. - • S.A.: ezºz -&Y2.4. * <=424xazzozz 2 YYºzez 2,42&ezº f ! Jºec exag | evez72 w Tº 27:7/7 A: cyca /es sº-º-º: ** -Yº 105 Sketch No. 3 shows the method of calibration used to determine the pounds of brine discharged by the brine circulating pump per revolution. To do this a by-pass or shunting connection was made in the brine line from the coolers to the brine storage tank. With this connection the brine could be thrown into a separate receiving tank the number of strokes of the pump required to fill same being recorded by an electric recorder the brine in the receiving tank being weighed before it was returned into the general system. In this way an accurate determination could be had as to the weight of the brine discharged by the pump per revolution, and thus a record be kept of the weight of the brine circulated. With this apparatus it was possible to calibrate the pump at any time during a run without in- terfering with the operation of 'the plant. - Sketch No. 4 shows the method used to calibrate the meters used to determine the amount of water used by different parts of the apparatus. The readings of the meters were corrected by the actual weight of the water discharged into a receiving tank. Among other things the plant had been used to determine the difference in efficiency of Horizontal Double Acting Compressors and Vertical Single Acting Compressors operating under similar conditions. To obtain this data a Horizontal Double Acting Cem- pressor of the same size as the Vertical Single Acting Compressor (12%"x18") was built and attached tandem to the Corliss Steam Cylinder as shown in Fig. No. 1. As both compressors were driven by the same engine and connected to the same system, the data ob- tained were very valuable. The data given in Tables No. 1 and 2 were obtained by using the Double Acting Compressor shown in Fig. No. 1. When the Double Acting Compressor was in service the connecting rods of the Single Acting Compressors were disconnected. A section of the Double Acting Compressor used is shown in Fig. No. 2. This paper is intended to be in answer to Third and Sixth Ques- tions of the Second Commission,-viz: 3rd Question—Investigations as to dry refrigerators and wet refrigerators, with their corresponding advantages and disadvantages. Methods to be used for the determination of production and output under these two systems. 6th Question—Investigations as to the operation of the con- densers under the dry system, also under the wet system—Results of trials—Respective advantages and disadvantages. Experiments on dry and wet Compressor pro- cedure of Condensing Cold Steam Machines. By Adolf Tegetmayer, Chief Engineer at the Linde Ice Machine Company, Wiesbaden. (All rights reserved.) At the I International Congress of Refrigerating Industries, held in 1908 in Paris, Herr Direktor Dr. ing. G. Döderlein, of Chemnitz delivered an eteaiemely nteresting lecture on the theme: «Wet and dry condensing procedures with automatic regulating process of the Condensing Cold Steam Machine.” In his former position as Chief Engineer of the Linde Ice Maschine Co., Herr Dr. Döderlein had had plenty of opportunity to become thoroughly acquainted with the new manner of working Compression Cold machines inventeer-by this firm, and he personally took part in the improvement of the over-heating instalment; he was thus able, with short theoretical notes, to explain the characteristics of the « dry Compressor process» and to give practical directions for this work. These directions admit of being concisely Sxpressed in the sentence: «One must work as dry as possible in the com- pressor and as wet as possible in the refrigerator, the pressure tubes of the rxompressor must therefore always be hot, the suction tubes, however, must ctill be white.> & It being my honourable task to-day to report, to so well-read an assembly of colleagues, on the working results, and the advantages and disadvantages of the dry compressor procedure, I cannot be expected to more closely examine into the theoretical experiments of my highly esteemed * former colleague. I must, rather, limit myself — as introduction to my own statements — to briefly recapitulating the most important results of his work. The ammonia compressors — which must here be considered in the first place — used commonly to suck in wet vapour from the refrigerator, so that the harmful space of the compressor cylinder, in the end-position, of the piston, was prevailingly filled up with liquid ammonia. ... When the expansion began this liquid vaporised and thereby weakened the volumetrical effect of the compressor very considerably, because the piston had to pass a noticeably long distance before the pressure in the compressor had sunk 107 below that in the refrigerator. As a result the suction valve could open an more wet vapour be sucked in. The volumetrical and indicated degree o effect will therefore increase with increasing superheating and reach their highest value when the harmful space in the compressor is filled with over. heated vapour. But the transference of cold in the Refrigerator, and con. sequently the manner of working of the apparatus, is best if the vapours are still thoroughly wet on leaving the Refrigerator. From this may be seen that a Compression cold vapour machine attains its greatest effective power if the wet steam from the Refrigerator is dried in a special separator lefore entering the Compressor. The Compressor then gets only dry saturated steam, while the distillation is conducted directly to the Refrigerator again. By carefully setting the regulation valve at incomplete superheating (in which case the pressure tube temperature varies pretty considerabl, ) a certain increase in the power of a Compressor that works without special steam drying, might be obtained. It is invariably endea oured to do this in guarantee trials. Such regulation is, however, difficult and can only be done for a time with great attention; the practice seems to be almost excluded in practical permanent working, especially in cases of changeable conditions of working, - When working with superheating plant —- strictly speaking -- during the state of permanence the refrigerant must flow perfectly regularly through the regulation valve. The Compressor sucks this from the Scparator in the form of dry steam. According to experience, however, in normal even working, the Regu- lation Valve may often be left for hours in one position, owing to the fact that the liquid stored in the Separator and Refrigerator give a certain ba- lance. The attaining of the greatest effective power of a Refrigerator de- pends far less upon the machinist than formerly. The regulation by hand, by means of the Regulation valve, may also be entirely replaced by the automatic Regulating Apparatus (with slow rota- ting feed cylinder) invented and patented in 1907 by the Gesellschaft für Tindes Eismaschinen, for by this apparatus a correct dry compressor pro- cess is continuously attained even when large fluctuations take place in the effective work of the Compressor. t So much for the Herr Dr. Döderleins performances. Let us now con- sider the history of the development of the dry Compressor proceduce so- mewhat more closely. The endeavour to hinder liquids from entering the Compressor cylinder, and thereby to prevent the dangerous liquid strokes, is by no means new. As early as 1882 Herr Franz Windhausen, in Berlin, patented a fri- gorific machine working with bisulphide of carbon. In the Steam dom~ of the Refrigerator of this machine a drying apparatus was provided in order that the steam might be as free as possible from liquid when it entered the Compression cylinder. This apparatus consisted of a container provided with 108 an annular jacket against the sides of which the liquid sucked in was hur- led by the centrifugal force. Thus separated it was led back by downward tubes into the Refrigerator. This is certainly the first case in which the organic connection between Refrigerator and Separator came into promi- nence. In this Windhausen Machine the Refrigerator consisted of a tubular boiler through whose tubes the salt water to be cooled circulated, whilst the vaporising liquid surrounded them. Departing from this arrangement, Herr Professor Raoul Pictet, in his sulphuric acid cooling machine, formed the large collector of the Refri- gerator (which latter consisted of a large number of short pipes) into a Separator, and connected it by means of a wide perpendicular stand pipe with the separating piece adjoining the lower. Spiral ends, so that the Steams and the Sulphuric acid coming simultaneously out of the upper Spiral ends immediately flowed back into the stand pipe, and there, through their hydrostatic pressure, overcame the slight resistance that the short, wide single spirals offered to their flow. Thus, also in the Pictet machine the Separator is organically connected with the Vaporiser, and must be con- sidered as an integral part thereof. The Gesellschaft für Lindes Eismaschinen A.-G., Wiesbaden, on the other hand, in their patent, an epoch-making one for the development of the dry Compressor, separated the Separator from the Vapo- riser, and connected it as independent apparatus, by means of special Con- ducting tubes, with the suction tubes of the Compressor. Only by this means was it made possible, on the one hand to make a single Separator suffice for a whole number of Refrigerators (for example: for the Generator, the sweet-water cooler, and all the Spirals of an intricate cellar cooling by means of direct Ammonia evaporation), and on the other hand, also to make all the other Compressors of a large Refrigeration plant suck from this one Separator. - In this way, at one blow, the road was made easy for the centralisa- tion of working, which I shall later on consider in detail. Naturally, it be-, came necessary, in some way or other, for instance by a high fall, or by pumping, etc., to give the liquid collected in the separator the pressure re- quisite to overcome the resistance of the long, narrow ammonia spirals and often very ramified piping. * In the above mentioned first Patent of the Gesellschaft für Lindes Eis- maschinen the intention was already expressed, if need arise, to press the separated liquid, by means of a pump, into the piping leading from the Condenser to the Regulating valves, that is to raise the pressure of the liquid from that of the Refrigerator to the full Condenser pressure, which, later on, proved particularly advantageous in the superheating apparatus of large refrigerating plants. In the Schmitz separating installation, invented at almost the same time as the Linde process, the so-called “primary liquid from the Regula- 109 ting valve does not enter directly into the Vaporiser, but into the Separator, where it separates from the steams formed behind the Regulating valve and mixes with the liquid that therein separates from the wet steams coming from the Vaporiser and in consequence is known as “secondary liquids. In the Schmitz apparatus, therefore, only the liquid, free of steam, gets from the Separator to the vaporiser, and by this means the resistance of the latter to flow becomes noticeably less, though for the same reason con- siderable quantities of liquid more easily get into the Compressor than is possible in the Linde arrangement. - Naturally enough, as Soon as the Gesellschaft für Lindes Eismaschinen had achieved their quick and complete success with the dry Compressor process a number of inventors and constructors took up the subject. Thus Herr Friedrich Stein in Cannstatt patented an arrangement in 1904 and 1905, in which alternately either the “primary liquid went imme- diately from the Condenser to the spirals of the Refrigerator, or the “se- condary liquids, collected in the Separator, was conducted into a special Vaporiser spiral by means of a piston rod valve provided with a float. Somewhat later Herr Arno Keilbar in Munich patented a Separator of special construction with zig-zag dampers. These can be partly closed for the passage of the steams to regulate the extent of the separation and the superheating temperature in the Compressor. The separated liquid is retur- ned by means of an automatic apparatus consisting chiefly of a vessel with two valves guided by a float and two self-acting back stroke clappers. Shortly explained this returning apparatus works as follows: The separated liquid, through its own weight, first passes out of the Separator, placed high up, into the empty vessel, which it fills. This causes the float to rise and opens the first valve, thereby allowing liquid to come from the Condenser and through partial vaporisation to force the whole of the liquid contained in the vessel through the second back stroke clapper into the Vaporiser. Finally the steam that has collected streams through the second valve, ope- ned by the sinking float, into the Separator and the game begins afresh. In the arrangement invented by Herr Wilhelm Kern, in Chemnitz, for returning the separated Refrigerant to the Vaporiser, a self steering Diffe- rential piston pump, driven by the liquid Refrigerant and by the super- pressure between the Condenser and the Refrigerator, is introduced in place of another pump. This sucks in the separated liquid and forces it into the spirals of the Vaporiser. Here the separation of the liquid takes place either in a special Separator adjoined to the suction piping, or else in the large Accumulator of the Refrigerator suitably adapted and connected into a whole with the Distributor. The Regulating arrangement constructed by Herr Karl Theodor Schröder, in Düsseldorf, for the automatic returning of the Refrigerant, is distinguished by a float, open at the top, which serves to guide the Regu- lation valve. This takes up both the primary liquid coming from the Con- 110 denser, and the secondary liquid coming from the Separator, and leads them, through the pipe which dips into its hollow, to the Vaporiser. Further, adjustable dampers are arranged in the Separator to regulate the degree of superheating. . The constructions just described may suffice as examples of the various possibilities of returning the Secondary liquid to the Refrigerator, and we will now, on the basis of the numerous working results to hand, consider in detail the simplest arrangements that serve the purpose, whereby Ammonia Compression Machines shall be our chief theme. -a yºza. ******62.P. ico 3 5Riate 4. *. º º $. s: 1A ~! •%. 5.4, ! Saxo~for-4 vºst.…yoted, *i. 3.44% ºf &mdenzalo. tº º T #2%ijesake. - &t.….'…w f res º 19e., b. & (“y oł. ck. Sara "...fotº -, It must first be mentioned that the separation of the liquid from the steam takes place very easily, so that the various constructions and forms of the Separator, if sufficiently large, will always give equally good results. It has also proved to be the case that the oil circulating in the machine, in so far as it is not taken out of the oil-collector, also collects in the Separator and may easily be let out of this at suitable periods. On the other hand the returning of the liquid offers considerable difficulties in many ways. Naturally, the simplest way is to place the Separator so high that the separated ammonia flows back to the Refrigerator by its own fall, as is shown in the following scheme, Fig I, * 111 At the same time the entrance of the Secondary liquid into the feed of the Primary may be made easier by means of a simple Radiation apparatus. The great advantage of this arrangement is the absence of all movable parts subject to wear, and it may be used to good purpose in small, new plants with only one Refrigerator, especially if the resistance to flow be reduced by the choice of several comparatively short spirals, and the higher cost of the Refrigerator arising thereby, be reckoned. Particulary great, too, is, in this case, the insensibility of the Regulation, that is the difference between the position of the regulation valve at which the periodical suction of the Refrigerator begins, and that at which the pressure tubes of the Compressor become cold, i. e. the superheating ceases. As a rule this simple principle cannot be applied in plants having several Refrigerators, because every Vaporiser must have its own Separator, and one usually has to do with Refrigerators of various constructions, whose Jong, often much twisted Spirals make a considerable resistance to flow probable from the outset. In such cases small pumps with rotating plunger, or simple cog-wheel pumps prove good for driving the separated liquid. It may, moreover, be recommended, to connect the pressure pipes of the pump with the liquid pipes of several Refrigerators — as is seen in Fig. 2, below — in order that the superheating installation may not be interfered with should one or more Vaporisers be stopped working. Such pumps produce, even when sucking in dry steam, a Suction or Super-pressure of about 2 atmospheres and in driving the Secondary liquid, in continuous working, may easily overcome a super-pressure of from “5 to 8 atmo- spheres, though, to be sure, their effect is then rather slight. It stands to reason that these pumps are placed beneath the Separators, and as near as possible to them. The pump must be sufficiently large to drive the largest quantity of separated liquid that can occur when all the Compressors and Refrigerators connected with the Separator are working. As this maximum quantity of Secondary liquid only occurs temporarily, ail such pumps work discontinuously in actual practice, that is they work at full power for a short time and then run empty for some minutes, until a suitable quantity of liquid has again accumulated in the Separator and the Suction tubes of the pump. In some cases, where a large resistance to flow has to be reckoned with, a back-stroke valve is inserted in the pressure tubes of the pump, to avoid the possibility of the steam that comes from the Regulation valve with the Primary liquid entering backwards through the pressure tubes into the pump, and, by filling this, preventing the flow of the Secondary liquid. In the case of large Refrigeration plants, where several Refrigerators are used together or alternatively, the simplest and most reliable working is gained by returning the Secondary liquid to the Distributor of the Regulation thse Suotait; econnection pipes are shown dotted in Fig 2. In this case, of , sº 112 course, a carefully formed piston pump, with valves, must be employed, to bring the liquid ammonia again up to the full Condenser pressure. This -ºr manner of Returning offers the great advantage, that not only the Primary, but also the Secondary liquid must pass the once set Regulation valve, that is, that an increase of the Secondary liquid causes a corresponding decrease of the Primary liquid. - * * * For under all circumstances, the small piston pump drives the Secon- dary liquid supplied to it and presses it even back into the Condenser, iſ, through an oversight, all the Regulation valves are closed at one time. Thus the self-regulation of the state of permanence is to a certain extent, | t! ... iſ º r Tº {º itſ Tºr UN * 3 - ? º º * %2. #stoaffod, 1.4.” 19 an Aa *A pſ. AE | 3.3% waxes tº *:::ſo * **** / ~) I coaxºne,” o/l < PL” 35ing * tº mº %rºp-ºf- º º U * - * ~-----" N - : i ! 3.5-tºn * *s- dº º ºs O = • -- -T-T |TT J. | | | | || **** T; ~ *-* * % Nfs Fig. 2. * of scoop at the exit of the last rotatory wheel, which in this case having about 6 mm just keeps within the permissible limits, the unavoidable reduc- tion of which for NH, and CO, would lead to quite unproportionate loss trough cracks. The two wheels in Figs. 1 and 2, therefore, probably show the smallest turbo-blower that for a proportional pressure of 1:4 could be practicalle executed, and this independent by of the kind of medium which determines the issue only as regards the expected cold production. * Let K stand for Cold production in hourly heat-units, then the volume sucked in during the same time is approximately expressed by V = K . . . - where v stands for specifice volume of steam and r for latent heat at the 133 suction temperature. Now as these last data are unknown quantities for a number of relevant bodies below 0°, we may, for a preliminary rough com- parison, also take v and r at 0°, and deduce therefrom the cold production of our blower when working with various refrigerants. The influence--of the warmth exhausted from the liquid trough the governor valve is not taken into account here. As is well known it somewhat reduces the conduction. In this way we obtain for V (always constant) the following table, in which the pressure interval was obtained by extrapolation. - Cold production of a Turbo-blower working with various refrigerants. *- || 3 ºf a & || AbsolutePressure 3 p: º- - 4) T- ... 3 in kg/qcm +: 3 # ää 5 3. . # E 5 | 3 & 2, ºf 34 3 || 3 = .# 3 ſ : Refrigerant # 5 - || ##|| 5 a. % = a = £ a 3 o P & | E 'E 5 | 5 § £ > * a 5 -E ; § a §3 = P- rd ; ro 5, .5 § 5 || 3 ; à 5 à T | # º §§ - O Sº O i. O $4 Carbonic acid CO, 0.010 55.2260 630 2°4 || 0:181|| 6 780 000 Ammonia NHs O'291|304'4|| 2:9 |103 3’5 || O'956|| 1 284 000 Sulphuric Acid SO2 o223 90'8|| 1:0 4'O 4-0 || 2:455|| 500 000 C.H -- Ether cº, > O 1°27 || 94-0|| 0 16 O'72 || 4:5 || 13:51 || 98 000 21, 15 Bisulphide of Carbon * CSs 1:76 || 90'O|| O'12 || 0:49 || 3-1 || 19:55 62 000 CH , Acetone CO< c. 4'26 ||1405 O'068 O-31 || 4'6|| 30-30 || 40500 3 Chloroform Cla-C-H || 2:37 || 67.O. O.061 || 0:27 || 4:3| 35.4 34 700 Carbon Chloride i CC1, 326 || 520 0023 0.15 || 65|| 627 | 19600 Alcohol C, HS-OH || 32:1 º 0.007 || 0-08 ||114|1356 || 9050 | Steam H.O 210-7 º O'0027| O'O32 ||113||347-O || 3 540 From this table it is evident in the first place that for production over 500,000 heat units per hour SOs alone comes into consideration, as it would hardly be possible to put up units greater than for 1,000,000 heat units. Work with SO, is further aided by the circumstance that for normal converter-temperatures the suction-pressure only differs slightly-from the atmospheric, -’so that leakage from the stuffing box, which is always only on the suction side, need scarcely be feared. At lower suction temperatures, it is true, danger arises of the atmospheric air forcing its way in which 134 would considerably reduce the cold production. With turbo-blowers too, therefore, the stuffing-box must be carefully formed and kept in good order. & k For smaller cold production the only other bodies at disposal are those whose conversion takes place in vacuum, so that they would always be liable to disturbances through the entrance of air. Such would naturally be the worse according as the specific volume of steam were greater and the cold production smaller. Then, further, most of these bodies form with air inflammable mixtures, which makes their employment for our purposes appear especially dangerous. True, with steam this danger does not exist, but the pressures are so low that the due maintenance of the vacuum with the aid of a turbo-blower seems very doubtful. Besides this, for medium production even, the blower must be so large that its practical execution is just as impossible as that of piston compressors for the same body. Finally let it be mentioned, that for relatively high boiling stuffs, such as Carbon-Chloride, Alcohol, and Water, the pressure proportion considerably rises, whereby a considerable increase in the number of steps as compared with the blower shown would become necessary. As practical result of our examination there remains therefore only the application of SO, for units above 500,000 heat-units per hour, while for les serproductions, as hitherto, recourse must be had to the piston com- pressor. The prospective advantages of the turbine for very large production are so evident as to make a trial in this direction appear promising of reward. - - 135 On the Manufacture of Crystal Ice from Exhaust Steam and the Practical Results obtained by this Process. By R. C. A. Banfield, Wiesbaden. The claims made respecting the article • Ice & have, in the course of time, become quite considerable and in some respects are on the increase, although they may vary according to local conditions or it may be possible to hold various opinions as to their being justified. Though Artificial Ice only will be dealt with in the following, a low estimate of the properties of good natural Ice and of its use in the human economy should not be assumed. Probably every representative of artificial refrigeration having had occasion to meet with the imposing cubes of blueish ice, measuring some three feet in every direction and hailing from the mountain lakes of Scandinavia or the Wenham Lake, will have felt that here is an article provided by nature, by no means to be despised, but rather challenging every exertion for its artificial substitute, Indeed, even to this day many ice consumers shew a marked prejudice against the mechanical product, the manufacture of which can point to a record of many years' ceaseless endeavour. The fact of the x Quality of Ice having been gradually improved is only one of the links of evolution, no invention having been immediately attained in its permanent and perfect state. If then conditions are present that Natural Ice does not enter into consideration, whether from its quality or by reason of its costliness, the ice-manufacturer has to face the problem, how best to satisfy the requirements concerning the quality of his product. Bearing in mind that the constitution of the freezing water exerts the most prominent influence upon the quality of the ice and that distilled Water offers a certainty of the absence of foreign substances and especially of harmful germs, and that by a careful de-aēration ice of excellent trans- parency can be secured, the employment of distilled water becomes obvious in all steam-driven ice-works. Three important points must, as a rule, be here carefully observed: the extraction of the lubricant from the exhaust 136 steam before or after its condensation; the de-aēration of the distilled water obtained; and the production of the distilled water in sufficient quantity at a minimum of cost. ×. Regarding from these three points the two chief classes of our present ice-machines — the absorption- and compression-plants — we find the former always and the latter frequently to be actuated by >liveč steam. This latter is further invariably employed by the combined compression- absorption machines, such using the high-temperature steam in the motor and its latent heat subsequently in the ammonia-generator. A. Sm a 11 Ice - Mach in es, producing up to 400 Ibs. ice per hour. With both systems of ice-machines of this small capacity the condensed steam will, under ordinary conditions, supply a sufficient quantity of distilled water to fill the freezing moulds. Each pound of live steam will produce refrigeration to the extent of about 220 negative BTU, corresponding to about 21/, Ibs of ice actually turned out. Herein is included the steam to drive the water-pump, shafting and agitators. a) Compression M a ch in e. Refrigerative Duty required for 400 Ibs ice hourly: 400 X 200 . . . . . . . . . . . . . . . 80,000 BTU. Each IHP in the compressor will eliminate per hour about 11,000 BTU, or say 4/5 th of this per IHP in the steam-cylinder, which would be hourly . . . . . . . . . . 8.800 BTU. The compressor-drive will demand . . . . . . . . . 9 IHP. and the accessories: water-pump, shafting, agitators . . 4 » Total IHP in engine . . 13 IPHP Employing a surface condensing engine with slide-valves the actual exhaust steam will amount per hour to about 13 IHP × 33 Ibs . . . . . . . . . . . . . . . . . . . 430 Ibs and adding to this the jacket-water, say . . . . . . . 33 × gives a total of condensed water hourly of . . . . . . 463 Ibs which is quite enough for charging the ice-moulds. The temperature-entropy diagram represented by Fig. 1 corresponds to the process described: any special expenditure of heat to obtain the neces- sary distilled water is not required. b) Small Absorption Mach in e. Assuming each Ib of live heating steam to eliminate 250 BTU in the refrigerator there will be required for the still: 137 per hour 80.000:250 . . . . . . . . . . . = 320 Ibs adding to this for the steam-pump circulating the weak ammonia- liquor 1 HP at 55 lbs steam per hour . . . . . . . . = 55 ° hence Total of destilled water per hour . . . . . . . . . 375 Ibs and it would be necessary to condense additionally . . . . 65 x making up a Total amount of charge for the moulds of . . 440 Ibs. B) Medium sized Ice Machines – 1000 to 2000 Ibs per hour. With plants of a moderate size, turning out 1000 to 2000 lbs of ice per hour, it is not possible to reckon upon the entire charge for the freez- ing cans from the exhaust steam of the engine only. Assuming the use of saturated steam in a one-cylinder surface con- densing engine for the smaller plant (using about 20 lbs steam per IHP and hour), and in a compound surface condensing engine for the larger one (consuming say 15% Ibs steam), we find approximately: Ice produced per hour . . . . . . . . . . . 1,000 Ibs 2,000 Ibs Distilled Water wanted per hour . . . . . . . 1.050 * 2.100 x BTU required in refrigerator (220 per lb ice) . 220,000 BTU 460,000 BTU Per IHP in compressor there are eliminated . 12.800 ° 14,000 x > * > steam-engine > * X , 10.250 x 11.200 x hence the compressor will require in engine . . 22 IHP 42 IHP add 25% for accessories . . . . . . . . . . 6 » 10 × thus total in engine about . . . . . . . . $ 28 IHP 52 IHP Exhaust steam per IHP, hour, 20 Ibs and 151/3 Ibs 560 Ibs 810 IbS Add 8°/o condensed water from conduits and Jackets . . . . . . . . . . . . . . . . . . 40 x 65 x Total distilled water available for cans hourly . 600 Ibs 875 Ibs, corresponding to 57% and 41' 3"/o of the quan- tities actually required. It is feasible, by means of the devices to be described, i. e. by the insertion of Water- Distillers, to obtain from every lb of >primary & steam 085 lbs of >secondary, steam, whereby a further amount of condensed water is pos- Sible of . . . . . . . . & s e º 'º e º a 480 Ibs and 690 Ibs making up a total of . . . . . . . . . . . . 1,080 Ibs and 1.565 Ibs. From this it results that the demands of the smaller plant are just Satisfied, but the supply of distilled water for the larger machine still runs short by about 25%. It will be here convenient to increase the specific consumption by intentionally reducing the vacuum as far as may be neces- Sary. The object will be attained, as soon as the specific steam-consumption will have reached about 22 lbs per IHP/hour, and in the case before us a 138 single cylinder engine would appear preferable to a compound one. But if the engine should have to develop any considerable power for other purposes, for instance, if cold stores were added to the ice-manufacture, or if a large amount of electric current had to be generated additionally, then the compound engine would be again in its place. This may also occur, if the available cooling water should be very warm, or if power for driving the compressor in the hot season should be materially increased through an unavoidable economy of the cooling water. º C. Large Ice-Machines, producing 2 to 5 tons (4500 to 11,000 lbs) - of crystal ice per hour. The exhaust steam here available from compound engines is greatly insufficient, hence it is necessary to adopt Water-Distillers with large heating and condensing surfaces, unless a very large amount of live steam be sacrificed for the make-up of coudensed water for the cans. For purely ice-making purposes, without simultaneous cold-storage or other accessory work, the water-distillers are best placed in series to each other, so as to utilize the 2 double effect.<. - Crystal Ice manufactured per hour : 2 Tons 5 Tons Corresponding Refrigerator Duty-BTU/hour 1,000,000 2,500,000 IHP in compressors, for 13,600 BTU/IHP/hour 74 188 IHP in Steam-engine . . . . . . . . . 92 237 Add for agitators, pumps, cranes etc. . . 20 56 Total IHP in engine . . . . . . . . . 112 293 IPHP Exhaust steam 19 and 15 lbs IHP/hour . 2,000 4.400 Add condensation from jackets and conduits 200 400 Total condensed water available per hour 2.200 lbs 4,800 lbs. This gives for the required amount with the smaller plant one half, for the larger one less than one half. The necessary supplement can be derived from the introduction of live steam into the condenser, a method hardly lending itself to economy. With two water-distillers arranged in series, it is possible to obtain from every pound of live steam admitted 21/2 lbs of distilled water. Water-D is till ers inserted in to the Steam-Co n duits. The special arrangements used for producing distilled water comprise as a rule the following: - - 1. The appliances for eliminating the lubricant from the heating steam, if the latter be derived from a motor. These are well known and have been efficiently developped, so that any description of them can be here dispensed with. It is important to avoid anything like an appreciable resistance for the steam passing through the oil-filters, in order to prevent losses of pressure and consequently of heat. 139 2. The Distillers proper, consisting mostly of horizontal or vertical multitubular boilers; they are sometimes equipped with heating coils. They are intended to condense steam of a higher temperature (>primary steam) to 2 Primary, distilled water and to utilize the latent heat thus released for producing a further amount of steam possessing a lower temperature (>secondary, steam). The latter is usually condensed in a surface condenser and thus supplies the 2 secondary & distilled water, which is entirely free from traces of the lubricant. For large installations the latent heat also of the secondary steam may be employed to raise, in a second distiller, further steam—tertiary steam, entirely free from oil and supplying after its conden- sation the stertiary & distilled water; in such a case there exist three different sources for the charging of the cans, formed at three different temperatures. The behaviour of the distillers and Öf the surface-condenser is, for a given quantity of heat to be interchanged, of course dependent upon the extent of the surfaces, their nature, freedom from deposit, the available temperature-step (to be discussed further on), the velocity Öf the heat- interchanging mediums etc. Generally the rules and conditions referring to steam-boilers apply here also. One special feature, however, consists in the water-distilling process taking place mostly under Vacuum, and in this case it is possible to arrange the feed automatically by adopting a suitable float-valve, thus doing away entirely with attendance to the distillers. 3. The distilled water, whether containing traces of the lubricant or not, is conducted into a vessel and there separated by the process of re- boiling from any air which it may still contain in the state of absorption. This can be effected either at atmospheric pressure or in vacuo ; in both cases it is well to condense the vapours boiling off and to convey them, together with the steam condensed in the heating coil, to the distilled water obtained. 4. Wherever the entire process is effected under vacuum, the pumps extracting the wet-air and lifting the condensed water must be carefully kept in order. 5. The further treatment of the distilled water, consisting in cooling, filtering and conveying it into a storage-tank and subsequently to the filling appliance for the cans, does not require any remark. If it be a matter of dealing with distilled water containing no traces of oil at all, its contact with iron must be avoided, for such liquor possesses a strongly Oxydising action which would give rise to a red discoloration of the ice hardly to be remedied by any means. From an economical point of view the engineer is specially inter- ested in the losses of heat arising from the use of distilled water as Compared with the freezing of ordinary water of good quality. From the Conditions already alluded to which influence the drop in temperature between the two sides of the heat-exchanging surfaces, it follows, firstly, that large heating surfaces will permit a small difference of tempe- 140 ratures and consequently small losses of heat also. But the considerable first cost of the rather expensive water-distillers prohibits in most cases very ample design, and it is usually considered satisfactory, if the drop in temperature does not exceed from 12°–18° C (220–32° F.). The deposits from the feed water will also cause a gradual increase of the temperature- step, amounting sometimes to 20° or 30° C (35" or 55° F). The quality of the feed-water — temperature, freedom from germs, hardness — is of course also a determining factor. t The working conditions of several crystal ice Installations furnished by the Linde Ice Company of Wiesbaden and in action since a number of years with water-distillers from exhaust steam are represented in the adjoining diagrams. For practical reasons the distillers are inserted into the exhaust steam-piping of the engine and are thus subject to vacuum. The former arrangement of placing the distillers between the boilers and engines has been recognized as less convenient and been mostly discarded; for the . sake of completeness this latter method is dealt with in Fig. 8 and 9. The conditions represented correspond to the ordinary local circumstances of working, not by any means to the best possible circumstances, as they would occur in test-trials for instance. Fig. 1 represents the heat-diagram of an engine working with an injection-condenser and utilizing the steam between the temperatures 170° and 45°/o C. (337° and 1139 F.); this corresponds to an ice-making plant freezing well-water only. There is no loss incurred for the production of distilled water of any kind. - Fig. 2 is taken from an ice-factory turning out daily 25 tons of crystal from distilled water entirely free from oil ; the primary steam being not at all drawn upon for freezing. The boiler steam drops in the cylinder from 170° C to 83° C (3370 to 1819 F), the latter being the temperature of the primary steam which, by giving up its latent heat in the copper worms of a horizontal distiller raises per hour fully one ton of Secondary steam at an evaporation temperature of 68° C (154°F). The loss of heat caused by the insertion of the water-distiller amounts to 17% of the available heat, if no distiller were employed. Fig. 3 shews the working of an Italian ice-factory for 27 to 28 tons of crystal ice daily, at an initial temperature of the cooling water of 22" to 25° C. (719 to 770 F); the vertical distiller is in this case of ample size, and consequently the loss arising from the interposed distiller is not greater than in the last example, namely 17°/o. In Fig. 4 the working conditions of three fairly large ice-plants in Egypt are represented, the cooling water for these being taken from the Nile or canal at 25° C. (77° F.) and over. The loss of heat incurred here from the adoption of the distillers is quite considerable and results from an over-production of ice. These plants were intended for 32 tons of crystal ice each daily, but were permanently worked for 40 tons output, 141 . All parts being thus overloaded by 25% beyond the ordinary stage, the temperature-drop between primary and secondary steam rôse to 28°C. (0 F), corresponding to a loss of heat of 29°/o as compared with distillers being removed. It may be remarked that under such unfavorable conditions the production of nearly 13 tons of crystal ice for every ton of medium coals burnt was proved, this including the necessary supply of distilled water. All three installations are furnished with a Sulzer tandem steam-engine using Saturated steam of moderate initial pressure, the main point being here not to obtain the least possible steam-consumption, but to furnish daily the 40 tons of distilled water to fill the ice-cans. & e 0.é g f £5 &yºcio CMAS Qºweſ. &A955. >\s. A gºomfiew. &ſo: &ow-powwºzºapw8 &tapronº. • . Qūwahoºw. &gºat &ºſtow Öxhowow Śzow. --- º --> * T. #23'- - . t A. 2. 8$f 6Sl- K. º MSQL * *l H---N===== Aft 3. * . . . * * * * = ***** ***** 1527 75°. 56°- *S*T 6$:l- Ös Fig. 1–9. Fig. 5 is taken from a German ice-factory possessing a water-distiller of ample dimensions, but with a deposit of scale on its heating surface detrimental to proper action. It will be perceived that here the conditions are as unfavorable as for the Egyptian plants. With 27°C. (40°F) difference between the primary and secondary steam the losses of heat attain 26°/o. Fig. 6 represents the heat-diagram of a large crystal ice factory turning out daily 140 tons. It is supplied with two large horizontal water-distillers, which are placed in series to one another to obtain the best advantage from the exhaust heat. For charging the cans three kinds of distilled water 142 are thus supplied, condensed respectively from the primary, secondary and tertiary exhaust steam at 73%, 56° and 43° C. (1639, 133° and 1099 F). The tandem engine driving the entire works indicates about 400 HP. Superheat of the steam is also not introduced here, as the large amount of 6/, tons of distilled water per hour would not be forthcoming, if the steam-consumption per IHP/hour were brought below a certain limit. Total loss of heat: 27%. In Fig. 7 the working conditions of the same factory, as under 6, are given, when the water-distillers are shunted par a 11 el to each other. The heat is then much more perfectly utilized, its losses amounting to 7% only, but against this must be set the considerable reduction of the distilled water — a decrease from 6"/2 tons to 4!/2 tons hourly. In all the cases hitherto dealt with the water-distillers are placed into the exh a us t steam conduit and work under vacuum. The following figures 8 and 9 represent in the same manner the con- ditions of heat-utilization, if the distillers are not inserted into the exhaust piping, but into the high pressure conduit between boiler and engine. Fig.8 corresponds to an initial pressure of the steam entering the steam cylinder at 11:8 atmospheres pressure, Fig. 9 to such of 85 atmospheres. In both cases the exhaust steam escapes with a temperature of 65° C. (1499 F) to the condenser: the losses of heat are here not excessive — 14 and 15°/o respectively. This arrangement, however, has been nearly discarded, the distillers being subject to considerable pressure and every degree of temperature-drop in the high pressure range corresponding to a far greater drop in pressure than would apply to the range of vacuum. Deposits on the active surfaces, or a possible forced working of such plants are liable to give rise to various difficulties and losses of heat, owing to the high pressures involved. In de pen de n tº D is till e r s for Supple m ent a r y d is till ed W a ter. In many cases the distilled water is produced both from exhaust heat and from an independent distiller of compound or triple action; these may be touched upon in the concluding lines. The expenditure of heat is here composed of the heat supplied to the steam-engine and of that supplied to the distiller proper. The heat utilized from every pound of steam by the former process is represented by diagram Fig. 1, and it is assumed that 44 lbs of ice can be obtained from every IHP/hour developped by the engine. If the engine's specific steam-consumption be 171/2 lbs per IHP/hour, it will be necessary to provide from other sources further 261/2 lbs of distilled water, in order to utilize the cold obtained from one IHP. In a distiller of triple action these 26/2 lbs can be obtained from 11 lbs of high pressure steam; that is to say, for 44 lbs of ice there must be spent about 28°/2 lbs of steam. But this is a far greater amount than would be required for working to the processes shewn by Fig. 2 to 9. 143 *. Following these latter, 16"/, to 23 lbs would suffice, i. e. an amount of heat from 70 to 24°/o less. In the United States the process is frequently followed of procuring the distilled water for freezing at atmospheric pressure, and then to treat the same further; this operation is more convenient, but not to be recom- mended as to economy of heat. The temperature drop utilized in these cases is only that between the admission-temperature to the engine and 100° C. (212°F), and the losses of heat connected with this process attain, compared with the conditions of Fig. 2 to 9, sometimes 50% and over. 144 Arrangements and safety devices for avoiding or minimising the damage done to compressors and coils, especially in the case of excessive pressure accidentally caused by mistakes made in the working of the plant or from any other cause. By G. Gillmann, Engineer, Luneville. Damage to compressors and coils may result from, mistakes, careless- ness, or from worn parts not being replaced in time. The most frequent accidents to compressors arise from mistakes; if . the compressor is started with the delivery valves closed, or if these valves. are closed before stopping the compressor abnormal pressure results, capable of causing breakage of the compressor. In order to avoid accidents such as have been indicated above, certain manufacturers furnish safety valves on the pressure side of compressors, which allow, in case of excessive pressure, of the escape of the excess from the pressure to the suction side. Generally the Compressors of carbonic acid plants are furnished with cast safety plates, which break in case of exsessive pressure; the gas escapes directly into the space around the compressor or is directed outside. This arrangement can only be practically applied in the case of carbonic acid gas, because of the nature of this gas. Another way in which breakage of the compressor could be caused is by the presence of a foreign body in the cylinder; of parts becoming detached during motion, breakage of the cotter of the piston rod, cross- head etc. In these cases the safety devices mentioned above would not be of any use; and it is necessary, in order to prevent abnormal loss of gas, to provide the suction and pressure parts with arrangements, automatically closing the pipe coils, in case of an excessive rush of gas. Such arran- gements are in existence, and have even been fixed on the outlet of steam boilers and are readily applicable to water gauge valves. It is very difficult to point out any device for minimising the damage arising from the natural or accidental wear and tear of the parts, especially of the coils; this is a question of good maintenance and attention. But still, it would seem desirable to furnish the inlets and outlets of condensers and refrigerators with the same devices as those described in the preceding paragraph. These devices, although in a way duplicating those placed near the compressor, would reduce the escape of gas in case of breakage of the plping. 145 NEW ARRANGEMENTS AND IMPROVEMENTS IN THE CONSTRUCTION OF APPARATUS FOR REFRIGERATION. RESULTS OF EXPERIMENTS THEREON. By F. E. MATTHEWS, M.-E. In its broader sense, a refrigerating system includes not only the heat removing means proper, but also the prime mover, or other means of supplying energy for operating the system, and means of prevent- ing the return of the heat removed. 5 Modern methods for utilizing a convenient source of heat energy for operating prime movers of compression refrigerating systems and generators of absorption systems as well as the most up-to-date me- thods of insulating cold storage compartments against the influx of external heat, are treated under the respective heads in other papers. Since recent improvements in the Freezing Side of Ice Making Sys- tems will also be treated in a separate paper, the subject of this paper will be considered in its narrower sense, viz., New Arrangements and Improvements in the Construction of the Heat Removing part of apparatus for Refrigeration. Even this subject is more comprehen- sive than one could hope to treat at all exhaustively within the com- pass of this paper, were it not for the fortunate general international interest that has of late been manifested in the subject of refrigera- tion which we feel fully warrants our assuming a comparatively thorough familiarity of all nations with American practice. The subject as limited will be considered under two principal heads:– I. Improvements in methods of manufacture. II. Improvements in design. Improvements in Methods of Manufacture. The one important requisite of all types of refrigerating machines, regardless of the nature of the refrigerant, is a closed conduit appro- priately designed for the circulation of the refrigerant, which can be made and maintained permanently tight. 10 146 Tightness of conduits in which ammonia is employed as a work- ing medium is especially important, not only on account of the disad- vantages arising from the extreme pungency of that gas, but also on account of the expense of replacing the lost refrigerant. The ex- treme subtleness of ammonia, coupled with the effect of contraction and expansion which inevitably occurs in the various parts of refri- gerating system, makes the solution of the problem of making per- manently tight joints, in ammonia conduits, particularly difficult. Ground joints, in which the adjacent surfaces of usually similar but sometimes dissimilar metals are brought into sufficiently close contact to debar de passage of the refrigerant are very effective where sufficient pressure can be brought to bear on the surfaces and the form of the parts is such that there is little tendency to change form due to expansion and contraction. Joints of this type are inherently expensive due to the scrupulous care required to make them tight, and consequently have no commercial application in refrigerating ma- chines outside of a few of the more important joints around com- pressors, and even there their use is limited in America to one or two manufacturers. At the present time the most common means of uniting the vari- ous parts of a refrigerating conduit is by flange unions between which is compressed a gasket of hard rubber or some other material suf- ficiently soft to fill the little depressions and correct for the usual ir- regularities of the adjacent surfaces. The flanges are themselves secured to the separate pipes of the conduit by threaded and screwed joints, where again the practical impossibility, under usual conditions, of cutting sufficiently accurate threads to make tight the “metal to metal” joints, forces the use of some filling substance interposed bet- ween the adjacent surfaces. This surface may be either metallic or non-metallic. The most common example of the former is soft solder, and that of the latter a cement made of litharge and glycerine. Soft solder is employed according to two distinctly different me- thods. By the first method one surface, usually the male, is “tinned” or coated with solder by first dipping in concentrated, then dilute, hy- drochloric acid to remove foreign matter, then into molten solder. This process may have to be repeated several times in order to get a continuous coating, but as the pipes are usually handled on end from a “gallery” the operation fortunately is not a very laborious one. The surface being thoroughly coated, the excess solder is removed by a few sharp hammer blows. After cooling, the part is screwed home. By this method the soft intermediate metallic substance is firmly united 147 by the “tinning” process with only one of the surfaces and is pressed into intimate contact with the adjacent surface by the taper of the threads. By the second method both male and female parts are tinned and the joint is screwed up while sufficiently hot to keep the solder in a molten state. By this method the intermediate metal is united by the tinning process to both surfaces. The female part should prefer- ably be the hotter so that shrinkage on cooling will tend to bring the surfaces closer together. This may be further assisted in case of pipes and flange unions by driving a tapered steel swedge into the end of the pipe before the solder hardens. This last operation is usually omitted when the pipes are handled on end, in which case additional molten solder may be poured over the joint to assist the “sweating” process. While the method of making up joints hot is the more popular, it does not possess all of the advantages of the first method. Such joints cannot be unscrewed or screwed up still further to stop a pos- sible leak, without first melting the solder. The price obtained for two-inch flange joints including flange union, bolts, gasket and two- screwed and soldered joints, when reasonably accessible, in lots of 500 or more, and made up in the shop may be taken as from $1.00 to $1.50 per joint. One of the oldest and most familiar methods of making screwed and soldered joints and one which is still quite popular notwithstanding its high first cost, is that in which the female fitting is recessed so that, when the pipe is screwed home, an annular space remains between the fitting and the pipe above the thread. After the pipe is screwed home the fitting is heated and the annular space is filled with solder which, if the outside of the pipe and the recess in the fitting have been properly cleaned and treated with a soldering solution of zinc and ammonium chloride, will securely unite itself by tinning to both sur- faces and thereby impose an effective barrier to any gases that may succeed in passing the threaded part of the joint. In this method the molten solder does not find its way into the thread and the joint can be easily unscrewed after applying sufficient heat to soften the solder in the recess. Aside from Soft metallic substances such as solder, non-metallie substances in the form of cements are sometimes used in making up ammonia joints. Permanently tight joints can be readily made when accurately cut, well fitted, scrupulously clean threads are tightly made up with a freshly mixed cement composed of fresh litharge and just 10% | 4S sufficient glycerine to give the mixture a semi-liquid consistency. As the success of this method depends upon the careful execution of every operation, there is unfortunately an important personal equation to be dealt with. - * * The difficulty of stopping leaks in expansion coil joints, especially when they are located in brine or ice freezing tanks, together with the annoyance and even danger incident to the failure of such joints, has given rise to various welding processes by which a large percentage of the joints heretofore made with flange unions are now united. There are in use today in the United States three distinct me- thods of welding pipes for use in steam and refrigerating system, “electrical,” “thermit” and “oxy-acetylene”. Electrical welding was the first method to find extensive application. The parts to be welded are forced firmly together by means of a screwed clamp by which they can be drawn together as they reach the welding heat. The terminals of a welding transformer are connected one to each piece to be welded. The imperfect contact of the two parts imposes a resistance to the passage of the electric current which gives rise to sufficient heat to make the weld. In this process a comparatively small amount of electrical current at ordinary line voltages is transformed by a “step down” transformer into a large amount of current at a very low volt- age. In fact, the voltage should be just sufficient to force the current up to working capacity of the transformer through the resistance of fered by the metal of the two parts to be welded.* The ultimate capacity of the transformer should be somewhat more than just suf- ficient to supply the heat required for the weld. The heat having been supplied to the surfaces to be united, through the agency of the elec- tric current, the weld is effected by pressing the two parts firmly to- gether. & - The thermit method of welding involves an exothermic chemical reaction between ferric oxide and metallic aluminum, the exact nature of which can be varied to some extent by introducing small quantities of steel punchings with the iron oxide when welding by this process. The ends of the two parts to be united are carefully faced and drawn firmly together by an adjustable clamp of appropriate form. In the case of pipe welding a hinged split cast iron mould provided with long handles to facilitate manipulation and so constructed as to *By Ohms Law, R. I–E, which in the present case means that the required voltage, E, of the welding transformer must be equal to the product of R. the resistance expressed in ohms, and I, the current expressed in anperes re- quired to supply the necessary heat to make the weld. This amount of heat expressed in calories per second is equal to .24 R 1*, or .24 times the resistance in ohms multiplied by the square of the current in amperes. ~ 149 leave an annular cavity around the pipe, is put in position centrally over the butted ends to be welded. A sufficient welding portion of ignited thermit” is then turned into the cavity, and as the ends of the pipe soften under the intense heat produced, they are pressed still more firmly together by tightening the screw clamps. The chemical reaction of thermit in which such a comparatively large amount of heat is liberated at the high temperature of approx- imately 3000 degrees Centigratde or 5400 degrees Fahrenheit, is re- presented by the following equation:- FE,O, + 2 A 1 == 2 Fe A1,O, (ferric oxide) (metallic aluminum) (metallic iron) (Alumina) 1.426 Kgm - .484 Kgm 1. Kgm .91 Kgm. The heat generated per .484 Kgm of aluminum used 1n the production of 1 Kgm of iron in the thermit reaction is as followsf:— - Calories B. T. U.’s Per Per P&il O Pound - Iron IrOn The heat required for reducing Fe from Fe203, taking place at 3000 degs. C * - -> 1768 3.175.7 The heat required for fusion of metallic iron, taking place at 1600 degs. C + ºr e 337 605.3 The heat required for fusion of aluminum, taking place at 1900 degs. C 425.71 764.66 - 2530.71 4545.66 To produce one Kgm. of metallic iron requires ordinarily 484 kilos. of aluminum which generates in the re- action 3455.76 6207.23 Surplus heat available 925.05 1661.57. As the products of the above reaction are approximately one Kgm. of iron and .91 Kgm. of alumina, making a total of I.91 Kgm., there will be approximately 450 Calories of heat available per Kilogram, or 81o B. T. U.’s per pound of thermit. The cost per joint for welding portions of thermit and rental of appliances based on not less than 100 welds, is quoted as follows:— Size Pipe.......... % % I 1–% 1% 2 2% 3 3% 4 Standard . . .0.53 0.58 0.74 0.89 1.00 1.05 1.56 2.20 3.12 3.43 Extra Heavy 0.58 0.63 0.84 0.99 1.20 1.56 2.76 3.67 4.17 4.25 Double Extra Heavy I.05 1.40 1.86 2.75 3.67 In ordinarily accessible work it is claimed that one man can han- dle the apparatus required and make about 200 two-inch pipe welds per day. *The ignition of thermit, since its “kindling” point is so high that it may be thrown into an ordinary, fire or poured into molten cast iron without burning, } as to be effected through the agency of some other high temperature reaction. The ignition powder usually employed is composed of Borium peroxide and powdered aluminum which can be ignited with a match or a red hot iron. #Dr. Goldschmidt—Zeitsch. An org. Chemie, 1902, p. 699. 150 For welding pipe exceeding this size two men are required. At the present time a third method of welding is fast coming into favor for refrigerating conduit work. By this method the heat is supplied by the burning in Oxygen of some such gas as hydrogen, common illuminating, or acetylene gas. ZZZZZTQ2. º •,• % N SES TH | N T LATE TH M C K Pu/ATE Tº IV ETE II*Aſ WE LITED JouryT ZZZZZZZZ Tº PE . . A N G-1. FS • - *lº. C YLINDER N__N FLANGE Diagram Showing Methods of Welding by Oxy-acetyline blow pipe. Fig. No. 1. When burned in air coal gas and hydrogen produce temperatures of approximately 2500 degrees and 3500 degrees Fahrenheit, respect- ively. When burned in oxygen, however, coal gas produces a tem- perature of about 3000 degrees Fahrenheit, which approaches the high- est temperature that can be produced in solid fuel furnaces; and hy- drogen from 4000 to 4800 degrees Fahrenheit. Acetylene gas when burned in air produces a temperature of only about 1800 degrees Fahrenheit, but burned in oxygen the temperature rises to about 6300 degrees Fahrenheit, a point far above the melting point of common commercial metals and surpassed only by that of the electric furnace in which temperatures of 7200 degrees Fahrenheit are readily pro- duced. The chemical reaction which gives rise to the almost phenom- enally high temperature resulting from the burning of acetylene gas in Oxygen is expressed by the following equation — - 2CH2+5O=2CO2-i-H2O, which means that the products of com- bustion of the two parts of acetylene and five parts of oxygen are two parts of carbon dioxide and one part of water vapor.” *For the benefit of those who are not conversant with acetylene gas and its principal commercial source, calcium Carbide, it may be interesting to note that although calcium carbide was produced by Edmund Davy in 1836 in con- nection with the production of metallic potassium, no commercial use was made of acetylene until 1892, when Thomas Willson discovered a process for making calcium carbide while trying to make metallic calcium from lime and coal tar - in an electric furnace. The dark colored slag formed in his experiments was at first thought to be metallic Calcium and the gas evolved when the slag was cooled in water was mistaken for hydrogen. This gas, however, was found to burn with a yellow instead of characteristic blue flame of hydrogen. Upon analysis the slag proved to be calcium carbide and the gas acetylene. Calcitim carbide is now made from lime (CaO) and coke which is chiefly carbon (C). The reaction is as follows:– CaC being calcium carbide and CO carbon monoxide, a combustible gas. The temperature at which this reaction is effected is about 6000 degrees 151 In practice when welding with the oxy-acetylene blow pipe, about one half the oxygen required for the complete combustion of the acety- lene is supplied under pressure through the torch, the remaining half being contributed by the air surrounding the flame. The ratio of oxygen to acetylene should be about 1.3 to 1. Both gases which are supplied under pressure from tanks, are brought together in a special torch carefully proportioned to the work to be done. These torches contain two small pipes for conveying the gases to the tip, the acety- lene conduit containing an enlarged section filled with asbestos and mineral wool to act as a filter and eliminate the possibility of the pas- sage of flame beyond the burner. The actual work of welding a piece of pipe is accomplished as: follows:— The edges to be united are beveled back almost to the edge, at an angle of about forty-five degrees. After the parts have been fastened in position the flame from the torch is applied to the bottom of the “V” until the fused metal from the sides unites and starts the weld. By the further application of the flame and the addition of metal as required the “V” is gradually filled up with small contribu- tions of metal fused and puddled together with the metal of the pipe walls. From this description it will be seen that strictly speaking oxy- acetylene or “autogenous” welding is more a fusing than a welding process, the adjacent surfaces of the two parts being fused together locally with additional metal of the same kind. Fig. 1. shows how a few of the more common metallic surfaces employed in the con- duits of refrigerating and ice making machines are united. The solid black portions represent the parts built in by the welding process. By this method not only wrought iron and steel, but also cast iron, aluminum and alloys which have hitherto been joined only by soldering and brazing processes, may be effectually united. The fixed cost of oxy-acetylene welds are, oxygen, which may be taken to be three cents per cubic foot, and acetylene, at one cent per cubic foot. At the prescribed ratio of 1.3 to I the cost for ox- ygen and acetylene per cubic foot of the latter consumed would be about 4.9 cents. IFahrenheit. The reaction produced by calcium carbide in water is as folllows:-- CaC, --2H,9 - C.H., -- Ca (OH) , C.H., being acetylene gas and Ca (OH) & calcium hydrate or slaked lime. * Ordinary _commercial carbide, yields from 4 to 4% cubic feet of acetylene #: ...; If absolutely pure the yield should be from 5 to 5% cubic feet per pound. The heat liberated by the combustion of hydrogen is only about 292 B. T. U per cubic foot and 62000 per pound, while that of acetylene is over five times as great or about 1572 B. T. U. per foot or 21850 per pound. The cost of welding pipes by this process is subject to almost too wide variation to warrant attempting to give figures. Following is a table of the quoted costs of welding butted joints in sheet metal of different thicknesses, from which it appears that the cost per lineal foot of weld based on the above prices of material and labor at 30 cents per hour, would be approximately as follows:-- Thickness From sº I's 3. 1. 1. is is # T 3. Sº . . . . ; ; ; Cost per lineal foot ic 2C 3.35c 5,8c 12,36c 244 45,4c 74c If the pipes to be united can be rolled over so that all the points to be welded can be brought successively to the top, it is evident that the work can be performed much more cheaply than if it is held rigidly in place. - On the basis of the above figures which are intended to apply only to flat surfaces, the actual cost of labor and material required to make a weld in two-inch pipe would be only about 3.6 cents. By this it seems that the oxy-acetylene blow pipe should also have an important field in the repairing of blow holes and porous places in connection with refrigerating machines. Manifold headers such as are employed in ice making systems are now built up by means of the oxy-acetylene blow pipe which unites. the several parts solidly and attractively. Multiple Effect Apparatus. Aside from what has been accomplished of late in the way of de- creasing the amount of refrigeration required to produce given com- mercial results by the use of high efficiency insulating material, and increasing the output of refrigerating systems per unit of energy ex- pended through the use of high efficiency combustion engines, the heat extracting portion of the refrigerating system is contributing to the general cause of increased efficiency, through the perfection of so- called multiple effect apparatus. g The important effect of the evaporating temperature of the re- frigerant on the capacity of refrigerating machines, more particularly those of the compression type, has long been recognized by the tech- nical refrigerating engineer. Unfortunately for the purchaser, how- ever, this knowledge has not always had such embodiments as would render its greatest advantages available and disadvantages avoidable. To more clearly show the results to be expected when a refrigerat- ing machine is operated under different conditions of suction and dis- charge temperature, the following comparison is drawn:—In this parallel a refrigerating or heat pumping system when drawing in heat at one level and discharging it at a higher level is comparable to 1 3 O a simple pump for sucking in water at one level and discharging it at a higher level. For the sake of comparison the former machine is shown on the right and the latter on the left hand side of the diagram, Fig. 2. The results of the action of the former machine is depicted in compressor indicator cards representing the various conditions of pressure encountered when the machine is operating between any two of the levels shown. - Diagram illustrating relative amounts of power required to elevate water and heat three different ranges of feet and degrees respectively. Fig. No. 2. Referring to Fig. 2, it is evident that if a quantity of water be pumped from any of the levels A, B, C, and discharged at any other levels L, B, V, the amount of power required will vary with each dif- ferent pair of limits. If, for example, 1000 pounds of water is to be raised from A to V, from IO to 190 feet, or a distance of 180 feet, the work performed will be 180,000 foot pounds and the power required tº- * e 180x1000 to do this amount of work per minute will be *.*=5.45 H. P. If, on the other hand, the same amount of water be raised from C to V, or from 50 to 190, a distance of only 140 feet, the work per- formed will be only I40,000 foot pounds, and the power required only 4.24 H. P., or 77.7 per cent of the former amount. Assuming for the sake of comparison, that the feet elevation in the case of the water pump be considered pounds in the case of the refrigerating machine or heat pump, the theoretical horse power required to raise heat or pro- duce refrigeration at the rate of one ton per twenty-four hours when operating between the back pressure, A, of ten pounds gauge, and the condenser pressure, V, of 190 pounds gauge, would be 1.35 H. P., whereas that required when the back pressure is C of 40, and the con- denser pressure is V of 190, would be 682 H. P. - In the case of the higher back Dressure the power required will be 154 only 50.5 per cent as great as that of the lower back pressure. Com- pressor indicator diagrams taken under the two sets of conditions as- sumed above would appear approximately as shown in the center of diagram, Fig. 2. 'From the foregoing it is equally evident that to let water avail- able at the 50 foot level flow to the bottom of the well at the Io foot level, A, and raise it from that level to the 190 foot level of discharge, V, and to allow heat that might be carried off with ammonia at a back pressure of 50 pounds corresponding to a temperature of 35 degrees Fahrenheit gravitate into ammonia at a back pressure of Io pounds, corresponding to 5 degrees Fahrenheit, would be to uselessly expend about 30 per cent. more energy in the case of the water pump and about Ioo per cent in the case of the refrigerating machine, than would be required under the more favorable conditions. If it is not necessary to keep the well pumped dry, that is, to remove all the water down to the Io foot level, and if it is not neces- sary to remove the heat below the 5 degrees Fahrenheit level corre- sponding to Io pounds back pressure, the most simple means of avoid- ing this useless expenditure of energy would be to allow the water level in the well and the temperature level in the cold storage compart- ments to rise to the maximum point allowable. If, as in the preced- ing case, this level be at C or 50, the saving in energy required to oper- ate the two systems will be as already shown. Where refrigeration produced by the direct expansion of a volatile refrigerant is required for a single, comparatively high temperature cold storage compartment the analogy is apparent. It not being neces- sary to maintain a temperature as low as that of the level, A, the pres- sure of the evaporating refrigerant may be allowed to rise until the corresponding temperature produced reaches level C, or if C be the actual cold storage temperature required, until the point is reached where the temperature of the refrigerant corresponding to the expan- sion coil temperature is just sufficiently below that of the cold storage compartment to provide the thermal head necessary to the flow of heat from the air of the refrigerated compartment to the boiling refrigerant in the expansion coils. This condition will be paralleled when the level of water in the well has been allowed to rise so near to that in the outside that there will be only sufficient difference in static head to produce an inflow of water. - While few of our operating refrigerating engineers fully appre- ciate the importance from an economical standpoint of maintaining the 155 highest possible suction pressure that required temperatures and the design of the system will permit, many of the larger operators of re- frigerating machinery are awakening to the fact and are equipping their ice making and refrigerating systems with appropriately designed re- cording back pressure gauges by which the care exercised by the operat- ing engineers in maintaining the highest possible back pressures can be readily seen at a glance by referring to a 24-hour back pressure record. The foregoing unfortunately has to do only with the most eco- nomical operation of which a given system is capable. In the case of a single temperature to be produced, as in the example cited above, refrigerating systems provided with liberal expansion coil surfaces which permit of operation with proportionately narrow thermal heads, satisfy the principal thermodynamical requirement of economy. It more frequently happens, however, that two or more widely different cold storage temperatures are required. If the loads happen to be fortun- ately proportioned one cylinder of a two or more cylinder compressor machine or one end of a double-acting compressor cylinder may be delegated to the work of compressing the gas returning at one suction pressure, the remaining cylinders or parts of cylinders, as the case may be, being employed to compress the gas returning at other suction pres- S111 &S. When two or more widely different temperatures have to be main- tained by the same machine and the duties to be performed at the va- rious back pressures are, as in the general case, not proportioned to the capacities of the compressor cylinders available, the problem becomes somewhat more formidable. Much inventive ingenuity has of late been brought to bear on means of dealing most effectively with these conditions. While the accumulation of water in the well up to the higher lev- els decreases the amount of energy required to pump it, this method unfortunately does not provide for draining the lower levels. Fig. 3 shows a mechanism which takes advantage of the various heads, A, B, C, at which the water enters the well, and at the same time pro- vides for the draining of the lower as well as the higher levels. The mechanical details of the apparatus are as follows:–The water entering at the different levels is conducted into appropriate storage tanks, A, B, C, each connected to the tank T. through a quick opening valve. If the suction pipe, which is made of unusually large diameter, is emptied and valve C opened, it is obvious that the water will flow to the bottom of the pipe and the advantage of 50 feet of head pos- sessed by the water at C will be lost. If on the other hand the valve A be opened first, the water from tank A will be admitted, filling the 156 suction pipe to level A. If the valves B and C be opened successively water from their respective tanks will be emptied into the suction pipe, that from tank B, filling the pipe from A to B and that from C filling it from B to C. The automatic operation of these valves may be ef- fected by the mechanism M driven from the cross head of the pump. and so arranged that its travel in a horizontal direction successively elevates the ends of the cables actuating the quick opening valves A B and C in the order named, after which the piston of the pump oper- ates to pump out tank T, after which the cycle is repeated. When the operation is carried out as described it will be seen. that the energy required to raise the water will be the sum of that re- quired to lift the three separate volumes of water from their three res- pective levels. These energies will be proportional to the areas of the three indicator cards, AV, BV and CV, Fig. 2 . Corresponding to diagram “a”, Fig. 2, is diagram “b” of the same figure, representing a refrigerating sytem of the usual type in which several rooms of different temperatures are cooled by refrigerant at One back pressure. Since the rooms A, B, C are to be maintained at temperatures of Io°, 30° and 50°F., respectively, a suction pressure. sufficiently low to maintain the Io’F. temperature must be employed, just as in the corresponding case the water pump must have a suf- ficiently low suction pressure to raise the water from the Io foot level A. Corresponding to diagram “a” Fig. 3 is diagram “b” of the same figure, representing a multiple effect compressor with an automatically actuated device, M, similar to that of diagram “a”, so arranged to ad- mit, first the IO pound, then the 30 pound, finally the 50 pound back pressure gaseous refrigerant to the compressor cylinder just as the piston is nearing the end of the suction stroke. Instead of a single diagram, A V, in Fig. 2 representing the work of compression done between the pressure of Io and 190 pounds, as would be the case if only one back pressure is carried to maintain the three different temperatures, or the three diagrams, A V, B V and C V, representing the work that would be done if each temperature. were produced under its most advantageous back pressure, by three separate compressors. Fig. 3 shows a single multiple effect diagram such as would be taken from a compressor like that represented in 'Pig. 3b. Valve A is open admitting refrigerant at Io pounds pressure from the low temperature expansion coils during the whole of the suction. stroke. When the piston reaches the point corresponding to B on the diagram, the valve opening mechanism M operates to open valve B. 157 admitting refrigerant at 30 pounds pressure from the medium tem- perature expansion coils. On reaching point “c” just before the end of the stroke, valve C is opened admitting refrigerant from the high temperature expansion coils at 50 pounds pressure. The compress sion stroke of the piston then increases the pressure to the discharge pressure of 190 pounds. It will be noted that there is one important point in which the operation of the water pumping mechanism shown in Fig. 3a is inad- equate for illustrating the operation of the multiple effect compressor as shown in Fig. 3b. Afºgºte J&o & #: ſº Ti º eso / So -I'ſ 4-0 Fº O © /26) i = 2, (C&J Diagram illustrating principle of operation of multiple effect Compression Hypothetical indicator card of compressor operating on three different back pressures. Fig. No. 3. The introducing of water at successively higher levels economizes power in that each volume is elevated from approximately the same level at which it enters the tank, T, but more than this is accomplished in the case of the multiple effect compressor. While the entire area of the card shown in Fig. B represents work of compression, only that part of the card lying above the line representing the 50 popund suction. pressure is performed by the compressor. The remaining area below this line represents the compression of the low pressure gases first ad- mitted to the cylinder by the higher pressure gases admitted later in the stroke. Fig. 4 is a reproduction of an actual indicator diagram taken from a multiple effect compressor. The dotted line shows the diagram produced when the higher pressure is not admitted to the cylinder, and the solid line that when operating under both pressures. It will be seen from this diagram that low pressure gas enters the compressor cylinder in the usual way, as indicated by the suction line, during the suction stroke, near the end of which, at a, the higher pres- 158 sure gas is admitted and the pressure at beginning of compression is increased from p to pl, the actual compression line being p 1 d, instead of p d. • * * - 27/se he ºwe et d \& goº & Sh rºy sº Sºe - S& Suchon Fressure 2.4% SSS. T. s." *— v-Section–Lice lºt ===-2's 4f ºries/ºstis diae &. Vac w w rº, L. tr. a- Indicator L)iagram showing Result of Introducing a back pressure p 1 24 lbs. at a after cylinder is filled at ..pressure p. 15 lbs. Fig. No. 4. Since the capacity of a compressor depends upon the number of pounds of refrigerant that the compressor will discharge per stroke which depends directly on the absolute pressure, it follows that the gain in capacity of a multiple effect compressor will be in direct proportion to the difference between the back pressure when operating multiple effect, and that when operating in the usual way. A single example will suffice to illustrate. If a compressor operating at 15 pounds gauge back pressure be provided with means of admitting gas at 25 pounds after the cylinder has been filled with the low pressure gas, the in- crease in capacity will be (25+15)-(15+15), equals 40–30 equals Io, or the increase in capacity will be 33% per cent. Other pressures will show still greater increases in capacity, one rather extreme hypothetical case figured out by the inventor of the system showing how seven different pressures, ranging from zero to 60 pounds gauge, may be admitted to the compressor one after the other in order of their increasing values producing an indicator dia- gram as shown in Fig. 5 and resulting in an increase of capacity of 400 per cent over that of the machine operating at zero back pressure.* While the advantages to be gained in keeping the condenser pressure as low as possible are second only to those of keeping the back pressure as high as possible, multiple effect condensers, though *See article “Multiple Effect Compressors,” by Gardner T. Vorhees, Ice and Itefrigeration, January, 1907. 159 their advantages from an economy standpoint have been pointed out, little has been done toward reduction to practice. The American builder at the present time contents himself with only such modifications of the usual type of atmospheric and double pipe condensers as he finds most conducive to the production of the lowest possible temperatures of condensed refrigerant. Where a complete counter current effect can be carried out in which the coldest incoming cooling water is brought in proximity to the hottest of the incoming gases, as in the case of the double pipe condenser, several different means are employed for reducing the final \ \\\ v \ NY N N. N. NNN ** N. NNN N'S ! N. S SS Nes s- Nº. N. “J. <> S SSS &; 63. S.J. S. S. Sis =35: # = Svote on tº tre -t. Y relº- 2–ºsº Y assis.tx. £1tze. Indicator diagram showing Results of Compression after introducing gas Six different back pressures 0 to 60 lbs. Fig. No. 5. temperature of the liquid. In atmospheric condensers the most pre- valent method is to remove the super heat of the gas with the outflow- ing warm cooling water by passing the hot gas from the discharge header through a few of the bottom pipes of the condenser, which are either submerged in the waste water in the condenser pan or being ar- ranged in the same vertical plane with the other part of the condenser, are exposed to the warmer cooling water just before it flows to waste. Another method is to conduct away the liquified refrigerant as fast as formed by means of a number of “liquid drip” pipes connected at the bottom of the successive pipes in the condenser and terminating in a common liquid header. Since the first work of refrigeration performed by the evaporation of the refrigerant is to cool itself down to the temperature of the re- frigerator it is of the utmost importance that the liquid pass to the ex- pansion valve at the lowest possible temperature. Since the cooling of the liquid by its own evaporation means an expenditure of refrigeration that could otherwise be turned to useful work it is of the utmost im– portance that the reducing of liquid temperatures so far as possible be effected by exterior means. Since the temperature at which the liquid evaporates in the refrigerator is far below that of the coldest cooling 160 water there remains between these two limits of temperature a con- siderable work of refrigeration to be performed by the refrigerant it- self. The expenditure of this refrigeration cannot be avoided, but where the work of refrigeration is being carried out at two different back pressures the efficiency of the system can be increased by cooling all of the liquid down to the temperature corresponding to the higher back pressure by its own evaporation, the vapors being compressed in a multiple effect compressor with other high pressure gases. This may be accomplished by means of a system illustrated diagramatically in an article entitled “Voorhees Multiple Effect Receiver,” published in Ice and Refrigeration, for August and September, 1909. In this system the liquid refrigerant from the condenser passes through an expansion valve into a liquid receiver which is connected to a flooded coil designed to do high temperature refrigeration, as for example, the fore-cooling of water for an ice plant, in which case the receiver temperature would be carried at about 15 degs. Fah. The vapors representing the liquid refrigerant evaporated in fore- cooling the water down to its freezing point and the refrigerant down to the same temperature, passes to the high pressure connection of the multiple effect compressor. The low temperature part of the system which may represent the ice freezing coils is supplied with 15 deg. liquid from the same receiver through a second expansion coil so arranged as to maintain a temper- ature of about 0 degrees in the coils. The low pressure refrigerant re- turning from these coils passes through the low pressure connection to the multiple effect compressor and after filling the cylinder is first com- pressed to the pressure in the fore cooler coils by the inflow of the high pressure gas itself, then to that of the condenser by the action of the compressor. It seems logical to expect that the saving in power and increase in capacity of a system employing a multiple effect compressor and re- ceiver over that of the ordinary system would be considerable. Let us assume that a 160 tons ammonia compression refrigerating system operates under conditions of temperature and pressure fre- quently existing in ice making plants, that is, a temperature of 90 degs. in the condenser corresponding to a pressure of 168 pounds gauge, and 0 degrees Fah. in the ice freezing expansion coils corresponding to an evaporating pressure of I5 lbs. gauge, for the production of Tootons of ice per 24 hours. Under these conditions approximately 26 lbs. of an- hydrous ammonia would have to be evaporated per hour per ton. If the water to be frozen enters the fore-cooler at 100 degs. and is cooled within two degrees of its freezing point the heat to be extracted per 161 pound will be 100 — 34, equals 66 B. T. U. To cool the water from 34 degs.to 32 degs. freeze it at 32 degs. and cool the ice down to the temperature of the brine or I5 degs. above that of the 0 deg. ammonia, requires 2–HI44+ (4%. 32 – 15)=(154 4% degs.), making in all 66–H I54%=220% B. T. U., the actual amount of heat to be ex- tracted to freeze a pound of water. - On the basis of 1.65 tons of refrigeration per ton of ice making capacity the amount of heat, including losses, that must be extracted by the refrigerating machine per pound of ice frozen would be 1.65 times I44 equals 237 B. T. U., but the actual amount required as first determined is 220 B. T. U. in which case the difference of 17 B. T. U., or about 8 per cent, represents loss by radiation and ice shrinkage in the tank room. Allowing 5 per cent loss by radiation in the fore-cooler the 66 plus 3.3 equal 69.3 B. T. U. of heat extracted in the fore-cooler is 29.1 per cent of the 237 B. T. U. of total heat extracted per pound of ice produced. When 90 deg. liquid ammonia is evaporated at 0 deg. Fah. the amount of refrigeration required to cool the liquid is I.O2 times 90, equals 91.8 B. T. U., which since the heat of vaporization at 0 degs. Fah. is 555.5 B. T. U. (latent heat of evaporation at 0 degs. Fah.) is 16.5 per cent. When the system is equipped with a multiple effect receiver only part of this amount would be evaporated in the receiver where the liquid is 15 degs. Fah. colder than the final temperature of the water going to the freezing tanks at 34°Fah, or 19°F. corresponding to 47 lbs. back pressure. At this temperature the latent heat of vaporization is 543. The amount of liquid to be evaporated to cool the remaining liquid and it- self down to 19°F. will accordingly be 90–19) times 102 equals 72.42 B. T. U., or 13.3 per cent. Of the remaining 86.7 per cent of the liquid 29. I per cent will be required to cool the water down to 34F., leaving 86.7 per cent—29.1 per cent equal 61.5 per cent to be evaporated at the lower back pressure in the ice freezing expansion coils. As the higher back pressure gas is introduced into the cylinder after it has taken in a full charge of low back pressure gas the introducing of IOO —61.5 equals 38.5 per cent of gas later will allow the capacity of the compressor to be increased in the ratio 61.5 plus 30.5 : 61.5 :: 1.62 : 100, or the capacity of the compressor for producing refrigeration has increased 62 per cent.” *At 15 lbs. back pressure a cubic foot of gaseous refrigerant weighs .1083 lbs. This however is only 61.5 per cent of the weight of a cubic foot of gas after the remaining 38.5 per cent of high pressure gas has been added, or the final weight of a cubic foot of gas will be 1083 : 61.5 :: .1760 : 100 and the back pressure of a gas weighing .1760 lbs. per cubic foot will be 34.6 pounds. 11 162 Automatic Refrigeration. The extending of the field that can be economically covered by the mechanical refrigerating system is taking place in two directions. The designing of systems for increasing efficiency, allowing a cor- respondingly reduced first cost, is fast increasing the number of op- portunities for the artificial to successfully compete with natural cool- ing means among large consumers of refrigeration. The perfecting of machines capable of operating with little or no attendance, entailing a materially decreased operating cost, is rapidly extending the use of mechanical refrigeration among the comparatively small consumers of 1Cé. In large refrigerating and ice making plants with supposedly cor- responding revenues, the cost of attendance is of only incidental im- portance. This expense which is practically as great for very small refrigerating plants as for those of five and ten tons capacity and up- ward, has been the chief factor in the past which has fixed the capacity limit under which the installing of mechanical refrigerating plants has not proved a good investment. The cost of attendance for steam plants operated for 24 hours per day is practically prohibitive for plants of less than Io or 20 tons capacity under usual conditions. The first step to reduce the cost of attendance in small plants is to eliminate night operation by the use of the brine circulating system, in which it is only necessary to operate a small pump for the circula- tion of the chilled brine through the cold storage compartments, while the primary refrigerating machinery is shut down. The use of small brine systems however does not greatly lower the capacity limit below which it is commercially practicable to install Small machines, as the first cost of the equipment increases as the time of operation decreases. A plant operating for eight hours per day, for instance, must be at least three times as large as a plant of sufficient capacity to produce the same amount of refrigeration when operated 24 hours per day. As a matter of fact, the power consumption of the larger- plant will be more than three times as great because of the much lower efficiency under which the brine system operates, because of the ad- ditional heat exchange that it interposes between the refrigerant and the product cooled. Fortunately for the small plant this increased first cost and increased cost of power, is often of secondary importance, to that of attendance and many small brine circulation systems operated from 8 to 16 hours per day under combustion or steam engines, or electric motors where the power is employed for other purposes, are in commercial use among small consumers of refrigeration. 163 Instead of the ordinary brine circulation system, a number of builders are now installing what may be called a congealing tank System. In such a system the expansion coils instead of being placed in a large brine cooling tank, usually outside of the compartments to be cooled, are divided into a number of smaller coils installed in thin galvanized iron brine tanks conveniently arranged on the walls of the cold storage rooms. This system eliminates the cost of the brine pump and power to operate it as well as the brine tank and the Space which it occupies, not to mention necessary insulation, and unavoidable radiation losses. The congealing tanks occupy a little more cold storage space than would be required for the direct expansion or brine \ Wa. ſ Semi-Automatic Refrigerating System. Fig. No. 6. coils, and congealing tank systems compare very favorably in conven- ience and cost of operation with the brine circulation systems. Semi-Automatic Refrigerating Systems. Where electric power is used the duties of the attendant arc somewhat lessened. The adjustment of expansion valves, lubrication. and precautions for safety, demand more or less constant attention in the ordinary system, so that slightly lightening the work of the at- tendant does not materially reduce the cost of operation. The use of automatic expansion valves, machines so designed as to be self lubricating, and reliable safety devices designed to protect the system against abnormal pressures resulting from failure of water supply, or the accidental closing of wrong valves, eliminates these most important duties of the attendant and enables the cost of operation to be propor- tionally decreased. Fig. 6 is a diagrammatic illustration of semi-automatic refriger- ating system in which, for purposes of regulation, a congealing tank such as is used in the system just described, is shown. The mechanical construction of this system is as follows:– “C” represents an enclosed crank case self-lubricating ammonia compressor, having both suction 10% 164 and discharge valves located in the head. This compressor is driven by a motor “M”, controlled by a hand starting box “S”. Ammonia from the ammonia receiver “R” passes to an automatic pressure reduc- ing valve “V” so designed as to maintain a constant predetermined pressure in the expansion coils, “e” and “el”. After passing through these coils the ammonia returns to the suction side of the compressor, is compressed and discharged into the double pipe ammonia condenser “C”, where it is liquefied, and flows back to the receiver “r”. To provide against abnormal pressures in the condenser in case of failure of water supply a high pressure safety valve “pv” is interposed bet- ween the high pressure and low pressure sides of the system. Ab- normal pressure in the discharge line raises this loaded safety valve from its seat, allowing the gas to “short circuit” back into the suction line. The compressor being of the enclosed crank case trunk piston type with a ring oiling outboard bearing and the motor also having ring oiling bearings; the expansion side being provided with a reduc- ing valve for the regulation of the amount of refrigerant supplied to the expansion coils; and the high and low pressure sides of the system being connected by high pressure safety valve “p'v”, the three requi- sites of a semi-automatic system for reducing attendance required are satisfied. Semi-automatic systems may be driven by combustion engines or other sources of power, in which case a signalling device indicating when the temperatures in the cold storage compartments have risen enough to require the operation of the refrigerating machine and drop- ped sufficiently to allow it to be shut down, may be arranged with a thermostat, battery and bell, as indicated in Fig. 7. Completely Automatic Systems. Semi-automatic systems require a certain amount of attendance to stop and start the compressors, as required by the conditions of tem- perature in the cold storage compartments. The completely automatic system has been developed to the end of eliminating the entire cost of attendance, not only for 12 hours per day but for 24. This system also eliminates the necessity of supplying excessive power required by the low efficiency brine systems. The principal disadvantages are that to be completely automatic such machines must be driven by electric power, the cost of which when supplied by central electric stations, and the high first cost of the necessarily complicated parts may more than offset the saving in attendance. Automatic refrigerating Systems nºn v be operated in accordance 165 with either of two distinct working cycles, depending on their relative chains of cause and effect. According to the first cycle a rise of tem- perature in the cold storage compartment operating through the agency of an appropriately designed thermostat, starts the electric motors which drive the compressor. The increase in pressure on the dis- charge side incident to the starting of the compressor, causes an auto- matic water valve to admit cooling water to the condenser. The decrease of pressure on the suction side causes a pressure reducing liquid valve to admit liquid refrigerant to the expansion coil. The evaporation of the refrigerant causes a drop in temperature which stops the motor through the agency of the thermostatic blade, operat- ing in the opposite direction. The reduced condenser pressure follow- ing the stopping of the compressor closes the cooling water valve and the increase of pressure in the expansion coils closes the pressure reducing liquid valve. al <–44- Completely Automatic Refrigerating System controlled by Thermostat. Fig. No. 7. According to the second cycle, a rise in temperature actuates a thermostatic expansion valve which admits liquid refrigerant to the expansion coils. The evaporation of this liquid produces an in- creased pressure which actuates a device for starting the motor. A drop in temperature closes the thermostatic expansion valve, shutting off the supply of refrigerant, after which a few strokes of the corn- pressor sufficiently reduces the pressure to actuate the motor control- ling device to stop the motor. Fig. 7 is a diagrammatic representation of a refrigerating system operating in accordance with the first cycle. The path traversed by the refrigerant is the same as in the case of the semi-automatic sys- tem just described. In this case, however, the thermostat “T” is connected to an appropriate automatic motor-starting device so ar- ranged that when the temperature of the cold storage compartment rises, causing the laminated thermostatic blade to make contact at “h”, the line current will flow through a solenoid “s”, raising the lever 166 arm “L”, completing the motor circuit and putting the compressor in operation. A corresponding drop in temperature causes the ther- mostatic blade to make contact at “c”, short-circuiting the solenoid “s”, allowing the lever “L” to drop, opening the motor circuit and stopping the operation of the compressor. A complete wiring diagram of an automatic starting panel, such as is employed for the operation of completely automatic refrigerating machines, operating by direct cur- rent, is shown in Fig. 8. The essential parts are, a solenoid switch “s” for operating the rheostat arm “r a,” a resistance “a b” a solenoid switch “b c”, a second resistance “c d”, and a third resistance “d e”. The blade of the thermostat for controlling the operation of the motor is connected at “b” between the resistance “a b” and “b c”. Assuming that the thermostat is so arranged that a rise in temperature causes it to make a contact at “x”, thereby short-circuiting resistance “a b”, an increased voltage will be impressed upon the remaining resistances. Resistance “d e” being already short circuited by the rheostat arm “a”, the line voltage will be sufficient to actuate the aux- iliary solenoid switch “b c”, causing it to close, completing the motor circuit through points “s”, “p” and resistance “r”. The closing of this switch completes the circuit through the solenoid switch “ss”, caus- ing it to slowly lift the motor starting rheostat arm “r a”, against the action of the dash pot “d p”, gradually cutting out the rheostat re- sistance “r” in the motor armature circuit. As soon as the rheostat arm leaves the first contact the resistance “d e” is thrown into circuit, increasing the total resistance in circuit “a e” and reducing the current through the auxiliary switch. This current is still further reduced when the thermostatic blade leaves contact “x”, thereby adding the resistance “a b”. When the solenoid switch “ss” has completed its work of cutting out resistance, it re- quires less energy, and the resistance “f g” is thrown into circuit, thereby reducing the current to just enough to hold up the weight of the rheostat arm. When the desired temperature has been produced in the cold storage compartment, the thermostatic blade makes a contact at “y”, short-circuiting and de-energizing the solenoid “b c”. This open-cir- cuits both the motor circuit and the main solenoid switch circuit, which stops the motor and allows the rheostat arm to return to starting position. As a matter of fact the introduction of certain safety devices makes the complete wiring diagram somewhat more complicate. Since the wiring of the starting panel is practically the same for direct cur- 167 rent in all cases, aside from the methods by which the resistance “a b” and auxiliary switch “b c” are short-circuited by the thermostats, the remainder of the above wiring diagram will be omitted in the follow- ing figures. - Fig. 8 drawn in heavy lines, shows how the safety device and ther- mostat are connected to the panel, at points “a”, “b”, “c”, just as the thermostat was connected in the former case, the only difference be- ing that the thermostat lines “CT” and “a h” have been broken for the insertion of the contacts of the high pressure safety device “HP". For the time being contacts “z” will be ignored and the line “ce” & : Current. - Fig. No. 8. will be considered unbroken. When operating at normal pressure the line “a h” to the starting side of the thermostat is completed trough & & 5 y contacts “w”. On the occurrence of abnormal pressures, however, the increased pressure under the diaphragm “HIP” lifts contacts “w”, open-circuiting the starting side of the thermostat, and then makes contact at “x”, completing the circuit around coil “b c”, and stopping the machine. It will be noticed that since the starting wire is broken at “w”, the machine is powerless to start, even if the thermostat is in contact with the staring point “h”. As soon however as the condenser pressure “HP” returns to normal, contacts “x” will be broken and contacts “w” will be made, again restoring the control to the ther- mostat. The breaking of the contacts at “w” before making contacts & & ––33 x” is necessary because of the fact that were the thermostatic blade in contact with “h” and the line “h a” not broken when contacts “x” are made, a circuit would be completed around both “a b” and “b c”, which would so greatly reduce the amount of resistance in the cir- cuit “a e” (Fig. 8) that the thermostat and safety device contacts and resistances “c d” and “de” would be burned by the abnormal flow of Current. 168 The extension of the diagram (see Fig. 9) included the additional high pressure device “B P” illustrates the application of a secondary safety device to prevent abnormal expansion coil pressures, the disad- vantage of such abnormal pressure being that in reducing them to normal when the machine starts up, a point of maximum mean effect- ive pressure will be encountered often sufficiently high to seriously Overload the motor. Safety Devices. Fig. No. 9. . The operation of this device is as follows:–Under conditions of normal operation, as, for example, at a back pressure of 25 pounds, the line “c e” is closed at “z”, and the line “b h” is open at “y”. So long as this condition continues the system will operate as though the new device “BP” were not in service. When the machine shuts down, however, and the pressure in the expansion soils and under the di- aphragm of the device “BP” increases sufficiently, as for example to & K }} & & 3 J 30 pounds, contacts “y” will be made contacts “z” will be broken. The making of contacts “y” completes a circuit “b y h w a”, around the resistance “a b”, causing the machine to resume operation. The breaking of contacts “z” prevents the machine from shutting down again so long as the back pressure is abnormal (above 25 pounds), even should thermostat “T” make contact at “L”. As soon as the & & X 3 pressure is reduced to normal, contacts “y” are again broken and contacts “z” are again made. The control of the system is thus re- stored to the thermostat. While there are a number of types of automatic motor controlling panels designed for alternating current, application of the thermostat and high pressure controlling device to the one shown in Fig. Io will suffice to illustrate the operation of the combination and the remain- ing diagram will be shown without the high pressure device connec- tions. In Fig. Io the making of contacts “h” and “1” by the thermostat "T" completes the circuit from wires “I” and “2” of the two phase four wire system, through solenoid “s”, the energizing of which attracts a laminated iron core which displaces the comparatively heavy crank 169 “w” to which is connected the main line switch “s” of the wires “4” Ji & & – ?) and “3” of the four wire circuit. The action of the solenoid switch is to throw the weighted crank from whatever position it may happen to occupy to the opposite position. This is effected through the factor . of inertia of crank “w” which carries the member by the center, so that its weight will help close the switch “s” as well as to make con- tact “y” or “z” as the case may be, and allows single solenoid to perform the functions of two, viz., to open as well as close the switch. Such controlling devices unfortunately can be used only where conditions are such that the motor can be thrown directly across the fine, or in other words, where no external resistance or compensator devices are required by the central station supplying the power. Where such devices are required in order to reduce the initial current inrush, somewhat more elaborate and complicated starters must be employed. While the apparatus described does not completely cover the field of either direct or alternating current motor devices, they will Wiring Diagram for Alternating Current—2 Phase. - Fig. No. 10. serve to illustrate the principles involved and give a general idea of how the automatic control of refrigerating machines is effected. Fig. II is a diagrammatic representation of a refrigerating system operated in accordance with the second cycle. In this case the con- trol of the motor is effected by the pressure of the refrigerant in the expansion coils, this pressure in turn being controlled by the temperat- ures of the compartment. An increase in pressure causes the expan- sion of the thermostatic fluid beneath the diaphragm of the thermo- static liquid regulating valve “r v”, causing it to open and admit re- frigerant to the expansion coils “e”. A drop in temperature produces a contraction of the thermostatic fluid beneath the diaphragm of this valve, allowing the spring to overcome the pressure of the gas, clos- 170 ing the valve and interrupting the flow of the refrigerant. The ac- tion of this valve is just the opposite of that of the pressure reducing valve illustrated in Fig. 7, the spring in the latter case tending to open the valve and the pressure of the gas beneath the diaphragm tending to close it when the predetermined pressure for which the valve has been set by proper adjustment of the spring has been reached. In the second cycle the starting and stopping of the motor is ef- fected by means of a simple mechanical device consisting of a dia- phragm, on one side of which the expansion coil pressure is exerted, balanced by the tension of a spring on the other side. Movements of the diaphragm under varying conditions of pressure actuate a lever which by making and breaking electrical contacts effects the starting and stopping of the motor through an automatic motor controlling panel as already described. d 5 s >-P Complete “Automatic” Refrigerating System controlled by Thermostatic Expansion Valve. Fig. 11. The automatic water valves employed in both of the systems described is a device similar in construction to the pressure reduc- ing valve that regulates the refrigerant, except that increasing con- denser pressure beneath the diaphragm effects the opening of the valve to admit more cooling water to the condenser, whereas an in- creasing suction pressure tehds to close the valve and shut off the supply of liquid in the case of the refrigerant pressure reducing valve. Automatic refrigerating machines operating according to both of the cycles described have been put into commercial operation and have demonstrated their unquestionable advantages, under certain conditions, over other systems. - The reproduction of the Bristol chart, Fig. 12, shows the time of operation and rest of an automatic system employed for cooling a wholesale beef house. This chart showed a representative day's operation of this machine in May, the lines of the diagram farthest from the center representing time of operation, and those nearest the center time of rest. The capacity of these machines is supposed to 171 be sufficient to perform the maximum cooling duty required in mid- summer with a margin of about ten per cent for suspended operation. The chart indicates a total operation of only about eight hours in the twenty-four. Mid-summer should show about 21-3% hours run. Automatic Control of Parallel Feeds. It is impossible to operate pressure reducing valves of the type de- scribed above in parallel, for the reason that the valve depends for its operation upon the pressure produced by its operation. Without Some such means as is here described there will be only one pressure produced and the pressure reducing valves cannot accordingly operate independently, as is necessary for the regulation of temperatures as required in several cold storage compartments. The automatic system, as described, has therefore a very serious limitation in the fact that all the expansion coils in a system must be arranged in series, a condition which greatly complicates the problem of producing desired temperatures, and imposes abnormal friction to the passage of the refrigerant. This entails a wide difference in back pressure at feed and return ends of the expansion conduit, making it necessary to operate the system under a lower back pressure than would otherwise be necessary in order to reach the lower temper- atureS. the elimination of this disadvantage, which enables automatic control to be extended to Systems of large capacity, may be effected by means of a system of automatic parallel feeds in which expansion coils of the various sizes required by the different cold storage compartments are installed in parallel, as in the case of ordinary non-automatic direct expansion systems. Each separate compartment is provided with its own liquid pres- sure reducing valve on the feed and gas stop valve in the return end of its expansion coil and a thermostat for indirectly controlling their operation. The main motor circuit is provided with a solenoid switch so ar- ranged that the machine will continue in Operation so long as the temperature in any of the several compartments is sufficiently high to keep its thermostat blade on the “operating” contact, and suspended operation only after all of the thermostats in the system have left the operating and made the opposite contact. Each separate expansion valve is supplied with liquid from a pres- sure reducing valve operating automatically as in the case of the “series feed” automatic system already described. To effect the shutting off 172 of the liquid in a given compartment as soon as the temperature in that compartment has been sufficiently reduced, the valve on the return end of the expansion coil is so designed as to be closed by a spring weight or other outside pressure controlled by the electric circuit through the low temperature thermostat contact. . . . . ." - ** * * e 24 Hours record of the performance of an Automatic Refrigerating Machine. The cycle of operations is accordingly as follows:–When the machine is at rest a rise in temperature in any of the several compart- ments causes the controlling thermostat to complete a circuit effect- ing the opening of the stop valve on the return end of the expansion coil in that compartment and the same time completing the motor circuit and starting the machine. The action of the compresser de- creases the pressure within the expansion coil of the compartment in question, which allows the automatic liquid pressure reducing valve to admit liquid refrigerant to the coil. A rise in temperature in other 173 compartments causes the opening of the stop and liquid valves of their respective expansion coils, throwing refrigerating conduits one after another into parallel circuit. As the compartments are cooled the controlling thermotats close the return stop valves on the ends of the parallel expansion coils and break the contacts in the parallel motor starting circuits until when the last valve is closed and the last contact broken the system suspends operation until rise in temperature in some one of the several compart- ments again occasions the traversing of the above cycle. This system may also be provided with automatic water regulat- ing valves and high pressure safety devices, as already described. The advantage of completely automatic refrigerating systems, both from the standpoint of convenience and economy of water and electric current, is apparent. Being necessarily operated by electric power their field of application is limited in many localities by the high prices demanded by central stations for the comparatively small amounts of power required. Fortunately, the tendency seems to be toward a down- ward revision of rates at the present time which will undoubtedly add much to what has already been accomplished along this line. It is to be hoped that the free and frank interchange of ideas bet- ween American engineers and their European brothers will lend new impetus to the great work of devising improved means of preventing waste, reducing want and eliminating the disorganizing influences of alternate glut and famine in every land. 174 CONDITIONS OF ACCEPTANCE, VARIOUS TESTS (RESISTANCE, STANCHNESS, Etc.) OF THE MATERIALS AND PARTS ENTERING INTO THE CONSTRUCTION OF REFRIGERATING APPARATUS Making These conditions Uniform; Rules to be Elaborated and Methads to be Determined by the International Commission. By PETER NEFF, M. E. Vice-Pres. The Arctic Ice Machine Co., Canton, Ohio, U. S. A. --------- It is necessary for an understanding of the subject assigned, to review briefly the development of refrigeration in America. While we are largely indebted to Europe for the initiative, yet on account of the larger demand with us, there has been perhaps a greater incentive. At first the scientific side of the industry was not given the con- sideration it should have had, but I desire here to pay tribute to the men of those times, for the greatest credit is due them, as the results many obtained, considering the materials they had to work with, were truly remarkable. However, they worked as individuals. They made no attempt to colabor. The result was an individualism of the most pronounced type. This condition was further accentuated by the patents taken out. Each manufactured the type of apparatus covered by the patents he con- trolled. None could see in the apparatus as constructed by a competitor- anything that was good. On the other hand, the purchasers being igno- rant of the art of refrigeration could not ask intelligently for the type of apparatus best adapted to their needs. As a consequence their choice was often more a matter of Salesmanship than of principles of refrig- eration. This period might have been of much greater value had the indi- vidual manufacturer kept more careful records, as much of the work that has been done since might have been avoided. In a few instances this was the case, and these have been of great assistance to the in- 175 dustry at large in later years, but in general what we know is tradi- tional. At almost any meeting of refrigerating engineers, we get from some of the men who worked during that period, instances of what was done, which are not only interesting but instructive. At the time the individualism spoken of was at its height, and the original patents were expiring, a circumstance occurred which forced this industry to the attention of the general public, as could not have been done in any other way. - The year 1890 found a large part of America without its usual crop of natural ice. Ice having become a necessity, the lack of it forced the attention of the public to, either its manufacture, or to some method of accomplishing the results formerly secured by its use. The manti- factories then existing met the demand to the best of their ability, which however, fell far short of what was needed. Such a condition naturally caused a number of persons to go into this line of work. As but a limited number of trained men could be found, many of those embarking in the manufacture of refrigerating apparatus at this time, met with ultimate failure. This marks the beginning of the sec- ond period, which was revolutionary in its character. Like all such upheavals, at the time it occurs, there is an apparent loss of ground, but when viewed in the light of history, such periods are distinct ad- vances; so this period, which was marked by failures and disorganiza- tion, occasioned by the ignorance of those embarking in the business, and by the dying struggles of the individualism of the preceding period, yet seems necessary to the development. Mechanical Engineers became interested through being placed in positions where refrigeration was required. These bent their energies towards its development. At the same time the financial and scientific world began to take an interest in it, and, while the unfortunate rela- , tion existing between the different manufacturers tended to disrupt and disorganize the general business, there was this leavening influence of more careful inquiry. At the same time manufacturers of allied indus- tries began to recognize that, in refrigeration they had a large prospec- tive business. The decline of individualism and the expiring of patents left open to all, that which had been limited to the individual. Some began to manufacture apparatus which did not represent so much their own characteristics, as embodied the better qualifications for refrigera- tion. - The uses of refrigeration increased rapidly, and, as this period closed, an attempt was made by the progressive manufacturers to for- 176 mulate certain rules and standards for refrigerating apparatus, which, if it had been possible to carry out, would have made largely unneces. sary that standardization which is now demanded. Unfortunately, there was still enough of the old individualism alive to prevent the carrying out of these ideas. This failure ushered in the third period, through which we have been passing for some years. º Many engineers with scientific training and practical experience in this line of work now became the heads of large installations, or set themselves up as consulting engineers. The old individualism was prac- tically dead, but there were no standards by which manufacturers might be guided; and here another form of individualism appeared which was the logical outcome of existing conditions. These scientifically and pratically trained men being now refrigerating engineers, and holding important positions, recognizing as they did that certain types of appa- ratus were particularly adapted for certain work, saw that, under the conditions, they could force any of the manufacturers to build accord- ing to their ideas. They therefore came to specify very particularly what they wanted and to set forth the tests that the apparatus must Stand to be acceptable to them. This has placed the manufacturers in a difficult position, for it is especially true in America, that the aim of the manufacturer is to produce cheaply; and this can only be done by repeating work, while if the apparatus has to be changed in detail for each plant, to suit individual ideas, it cannot be furnished at a price which comports with the manufacturers regular type of apparatus. It is these conditions that are forcing thinking men in our profes- Sion, not only manufacturers, but refrigerating engineers at large, to realize that certain general standards must be evolved which will be satisfactory to all concerned, and which shall tend to unify the industry. Certain standards America must have, not only for capacity, efficiency, and the like, but also some general standards for structural parts. In order that these may be acceptable, it will be necessary that they be advanced by a body of men not only capable of passing upon such ques- tions, but of such a character as shall convey authority. This function seems, in America, to rightly belong to the American Society of Re- frigerating Engineers, and if they can work in conjunction with other associations, or, what is better still, if all can be united in an organiza- tion of an international character, its recommendations confirming, as they must, the recommendations from the various associations, the ideal authority would be secured. The International Association of Refrig- eration, representing as it does, the best thought both in America and abroad, should take up this matter, and by working with the associa- 177 tions in the different countries, eventually promulgate standards which would be acceptable to all, and there would be ushered in a new era in the refrigerating industry which is only now beginning to realize its possibilities. In taking up the problem of standardization of structural parts of refrigerating apparatus, the question of capacity and efficiency, while not coming within the scope of this paper, are so closely associated with it, that their consideration at an early date by International Com- mission is most earnestly desired. As has been shown, the growing tendency of Refrigerating Engin- eers je to specify in detail the construction and testing of the apparatus, and it is the variety in these details, more than any one thing that is emphasizing the necessity for Standardization. The individualism of the early manufacturers led to a variety of guarantees, both as to capacity and material. Gradually the one year's guaranty against inherent defects became practically uniform, and sub- stantially in its present form will undoubtedly remain, as it is accept- able to all. Standard phraseology, however, is desirable and should be recommended. In this guaranty, the question as to whether the part which may have proved defective shall be replaced by the manufacturer, or merely supplied, should be left open, to be adjusted by the parties at interest in each case, for, to fix this definitely, might work a hardship on one or the other. There are two main divisions of acceptance. One refers to the parts entering into the apparatus; the other to the apparatus as a corn- pleted whole. The first of these two sub-divides into two classes: First, such parts as the manufacturer of refrigerating apparatus purchases, ready for installing as it comes from the original manufacturer, and on which he does no work, other than placing in position. Second, those parts upon which he does work. The first of these sub-divisions may be classed as follows: Ist— those parts used in common with other industries; and 2d, those espe- cially constructed for refrigeration. Taking up those that are common to this industry, as well as to others, such as engines, motors, pumps, boilers, steam and water fittings, pipe, brine material and the like; these are already sufficiently standardized, and their acceptance or rejection can be determined by such standards. Any further attempt at stand- ardization would only complicate matters. Second, those parts, manufactured generally by others especially for this trade, such as tanks, cans, insulation, refrigerants, gaskets, 178 cranes, and the like, these are all in the process of standardization by the manufacturers of such parts, and only two of these need our atten- tion. . . The first of these is the ice can. At the time of the attempt by manufacturers of refrigerating apparatus to standardize parts, cans were given special attention, and specifications both as to sizes and construc- tion were set forth. The sizes, weights of material, and general con- struction have met the approval of the trade, but standards should be made for the following. Ist. Whether or not the material shall turn over the band, or be flush with it? 2nd. The dimensions of the band. " ; ; ; 3rd. The location of the lifting holes. The other item embraces tanks, and by this is meant not only the brine and ice tanks, but tanks of all kinds, as well as the shells of coolers, absorbers, generators, and the like. In these the weights of material to be used, depending on the pressures, as also the pitch of the rivets, whether the riveting shall be hot or cold, size of angles, bracing and caulking should be determined. Taking up the second sub-division, namely, those parts on which the manufacturer of refrigerating apparatus docs work. There being regular standards for certain parts, which are the same as are used in common with other trades, their standards, as far as possible, should be affirmed. Under this head come pipe threads, dimensions of flanges for various pressures, and such items as bolts and nuts. * No attempt should be made to standardize any type of fitting or valve, but certain center to face dimensions, the internal and external diameter of tongue and grooved flanges, depth of groove, bolt circles and number of bolts should be recommended. The amount of pressure that compressors, valves, fittings, and other parts should be tested to, together with the minimum temperature of water used for such tests, when the test is for tightness, as well as for strength, should be specified. Where pipe is flanged, either with the use of solder, litharge, or other substances, the method of doing this should be determined, and the test for tightness, preferably by an air pressure, determined. It would be well if the distance between the coils in ice tanks, where different sized cans and pipe are used, could be settled, as well as the minimum amount of pipe surface to be used per ton of ice produced, this varying with the temperature of the water delivered to the cans; also 179 the minimum transmitting surface per ton of refrigeration per day for brine tanks and brine coolers of all types, but for these only recom- mendations should be made. Framework and covers of tanks are not susceptible of Standardiza- tion. Condensers are subjected to so many conditions as to render their standardization difficult, except that a minimum of surface should be recommended for atmospheric, submerged, double pipe, and Sheii type of condensers, depending on the temperature of the water available. The pipe surface for refrigeration depends so much not only on insulation but location and the work to be accomplished that any stan- dardization is doubtful. In all cases the refrigerating medium used must not be lost sight of. The tests must vary with same. The parts of the apparatus heretofore considered, if constructed in accordance with the standards adopted, their acceptance for ship- ment should not be questioned. We now come to the second part of our conditions of acceptance which covers the entire installation. It will be assumed that the parts entering into the installation have been acceptable for shipment under the standards for such parts. After being assembled, other test are necessary, which will be for tightness and workmanship as a whole. The year's guaranty provides against defects in workmanship which cannot be seen, and the test for tightness should be preferably by an air pressure, maintained for a certain length of time, within certain ranges of pressure or vacuum or both. The plant having been manufactured and installed under the standards of the original manufacturers of material, and of the re- frigerating association, it should be accepted by the purchaser as ful- filling the conditions of construction. As to the methods which the International Commission should pursue, we would suggest that, by means of existing organizations, they get in close touch with refrigerating engineers, manufacturers of re- frigerating apparatus, manufacturers of allied industries, and users of refrigeration; and that the Commission— Ist. Affirm the use of certain standards at present in use, as far as they are applicable to this industry. 2nd. That they standardige such parts as are well established and where it can be done without working any hardship to those interested. 3d. That for certain items, for which it seems inadvisable for the time being at least to make specific standards, that recommendations 180 be made for such parts, which may be ultimately accepted as standards, if found agreeable to the industry. To Summarize: It is recommended that an International Commission be appointed, which shall work in conjunction with the various associations already existing, and by means of these, be in touch with all interested in refrigeration. ~. That This Commission First. Affirm such standards as may be found to exist, which effect refrigeration. For example, for such items as prime movers, pipe, steam and water fittings, valves, boilers, brine material, insulation, refrigerants, gaskets, cranes and hoists, pipe threads, dimension of flanges, bolts and nuts. f - 4. Second. Make standards for such parts as are found to be well enough established that their standardization will not work a hardship . on any one. For example, ice cans, tanks, pipe flanging, the parts to be tested for strength and tightness, method of testing, pressures and temperatures employed, final test of apparatus as a completed whole. Third. Make recommendations for such parts, as in their judg- ment can ultimately be standardized, if found acceptable to the trade. For example—— Phraseology for year's guaranty. Center to face dimensions, bolt circles, number of bolts, depth of tongue and groove in flanges for fittings and valves. Center to center ice tank coils for different sizes of cans. Minimum transmitting surface per ton refrigeration for all forms of brine coolers. Minimum pipe surface in ice tanks per ton of ice. Various con- ditions. Minimum pipe surface for condensers of various types. That specifications demanding other standards be considered special, and treated as such by manufacturers. That acceptance should be determined by standards and recom- mendations set forth. . In Conclusion: Our aim has been to point out broadly— First—The necessity for standardization of structural parts. 181 * Second—The various parts of frigorific apparatus which may be considered. Third—The Method of treatment. It must be left to the International Commission to determine te details. Above all things a hearty cooperation by all interested is essential, without which the Commission's work will be of no avail. An interest must be first aroused in this International Congress, and by its members transmitted to the various organizations societies, and firms, which they represent. Let us pledge our hearty co-operation to the Commission, and thus help make its work, a lasting memorial to refrigerating engineering, which is just entering upon a career of usefulness to mankind, the greatness of which, is unquestionably beyond anything we can imagine. - 182 SUPERHEATED VAPORs EMPLOYED IN REFRIGERATION. By DR. J. E. SIEBEL, Director Zymotechnic Institute, Chicago. In response to your flattering invitation to present to this Con- gress a paper on “Superheated Vapors employed in Refrigeration”, I must say that I do so with considerable diffidence as the questions in- volved in this theme can only be approached in a more or less hypothe- tical manner, since both theory as well as practical tests are wanting in this direction, and since moreover the refrigerating media can ap- pear in the superheated condition at certain stages of the refrigerat- ing cycle only. - For these reasons, I will confine my remarks to some points of practical importance connected with the above mentioned stages in the refrigerating cycle, which frequently are referred to, somewhat vaguely, as wet and dry compression in practical parlance. Speaking on theoretical grounds in this connection, we may argue that since a perfect cycle of operations yields a maximum efficiency if the medium undergoes the least amount of change in its molecular constitution, the transition of the medium into a superheated condi- tion, would interrupt the continuity of its constitution in such a way as to lessen its efficiency. 's On the other hand, it follows from certain deductions which are laid down in my treatises on the thermodynamics of vapors,” that many saturated vapors are more efficient under certain available tem- peratures for power producing, than superheated vapors, and from this it might be inferred that superheated vapors are more proficient for refrigerating purposes, since in accordance with thermodynamic theories, the refrigerating and power producing efficiency of a medium stand in a kind of reciprocal relation to each other. In this connection also the question presents itself, whether those stages in the operation of a refrigerating machine, at which super- heated vapor can manifest itself, are so located along the line of changes of the supposed reversible cycle, as to be more conducive to increase the efficiency of a power cycle or that of a refrigerating 183 cycle. The latter would seem to be the case, judging from the fact the superheating of the medium takes place during the heatlifting of the medium since in this operation the superheated condition is more conducive to an increased refrigerating efficiency as above indicated. The fact that the specific heat of the saturated vapor of ammonia is negative, would also seem to lead to conclusion favorable to an in- cidental superheating during the compression stage. However, these thermodynamic theorems are still in an academ- ical stage with reference to the operation of the refrigerating media in question, and in drawing conclusions we must also not forget that the refrigerating cycles with these media, even if conceived as being operated reversely, do not strictly conform to the ideal cycles assumed by Clausius and others, for these media do change their state of ag- gregation during the operation. But, however unsatisfactory and unreliable, therefore, these theoretical conclusions may be, at least in a quantitative sense, they nevertheless give a preponderance of argument in favor of Superheat- ing in the compression stage. Contrary to these apparently concordant theoretical results, show- ing an advantage for dry compression, we find that practical tests con- ducted in refrigerating plants on a large scale, as a rule show a slight increase in efficiency for wet compression. In order to harmonize these apparently conflicting results, it be- comes necessary to consider not only the specific heat, but more particularly the heat conducting qualities of the refrigerating media at the chief critical stages in practical refrigeration. The heat conducting power of ammonia in its different states, al- though it has never been exactly numerically determined, doubtless shows differences in degree similar to that of steam in its dry, wet and superheated condition, the heat conducting power in the latter state being like that of a permanent gas, that is comparatively very small. Reasoning on the basis of these parallel conditions we can readly see, how an increased efficiency in refrigeration may be obtained with saturated, and even to a degree with wet vapor, although pure theory might demonstrate a greater efficiency with superheated vapors dur- ing the compression stage. For this purpose we need only remember that the most successful operation of refrigerating plants implies principally also a prompt ac- *The Thermodynamic and the Pneumodynamic Function by Dr. J. E. Siebel, in Ice and Refrigeration Jany. 191 0, p. 45 etc. 184 tion of the condenser which as now will be seen, cannot take place if the ammonia enters the condenser in a superheated condition, as would be the case in dry compression. In this condition the heat conducting power of the ammonia is so very small that the activity of the condenser may be considered prac- tically nil until the superheating has been removed from the medium. To avoid this it is indicated that the compressed ammonia enter the condenser in a saturated condition, or as nearly so as possible, for which reason the compression at least during its final stage, should take place with as little superheating as possible, To attain this latter end, the ammonia must be either fed to the compressor in a wet condition, or some liquid ammonia must be added during compression or artificial external means for cooling the com- pressor or the ammonia (by oil injection, water jacket, etc.) must be employed. Leaving water jacket and oil injection out of consideration, it fol- lows that the prevention of excessive superheating in the compressor is best accomplished by injecting the proper amount of liquid am- monia into the compressor from the liquid receiver, or if arrangements permit it, from that part of the condenser, in which the ammonia has just become liquid. & In the so called wet compression, the superheating during com- pression is generally prevented by feeding the compressor with so cal- led wet or supersaturated vapor, that is vapor containing liquid par- ticles in suspension. - This is objectionable, because not conducive to the greatest pos- sible efficiency for two reasons, mainly : In the first place the vapor so surcharged with liquid is a good con- conductor of heat and therefore a correspondingly great deal of re- frigeration is radiated by the suction pipe, where it will be a positive loss. -- This loss is increased by parts of liquid particles evaporating at this stage, thus producing additional refrigeration, part of it is also wasted in the manner indicated, as is very conclusively demonstrated by the ice forming on the suction pipe of machines operated in this 1112111161. In the second place the liquid particles carried by the wet vapor entering the compressor, have acquired the temperature of the re- frigerator, and now while acquiring the temperature of the com- pressor, dispense with a corresponding amount of refrigeration in a wasteful useless manner. - ^. 185 This waste of refrigeration, as well as the chief portion of those wastes incurred by radiation of the suction pipe, are avoided if the superheating during compression is regulated by injection of liquid ammonia from the condenser or liquid receiver, as indicated above. Reviewing the lessons which the seemingly conflicting purely theoretical considerations and practical experience give us, we come to the conclusion, that they may be most efficiently harmonized by operating the ammonia refrigerating machine during the suction and compression stage with dry, Superheated and saturated vapor succes- sively. Dry or even slightly superheated vapor to be provided for in the suction pipe approaching the compressor; and vapor, saturated or very nearly so to leave the compressor. In the intervening stage, super- heated vapors will be found during the first part of compression, which towards its end is saturated by liquid ammonia from the liquid re- ceiver or condenser. While in the foregoing remarks for simplicity's sake, anhydrous ammonia has been more especially referred to as the refrigerating medium in a compression plant, the said remarks will apply with equal force to compression plants operated with chloride of methyl or some other vapor. Results similar to the above have been arrived at in my treatise on the difference states of ammonia in refrigeration, published in 1906, the principal conclusions of which may find a place here, in as much as they refer also to the preferable conditions of the refrigerating agent in other stages of the process, viz: Boiling ammonia, wet ammonia, and saturated ammonia should be given preference in refrigerators, coolers and expansion pipes in general, in the order mentioned; superheated or dry vapor being objectionable wherever refrigeration is to be transmitted, except as hereinafter stated. Saturated ammonia should be given preference for the feeding of the compressor; superheated ammonia as well as wet ammonia being objec- tionable as a rule. -- Slightly superheated ammonia (almost saturated ammonia) to enter the condenser. Superheated ammonia for the conduction of refrigeration for long dis- tances in the absence of liquid ammonia or brine conduits and for long return suction lines. Liquid ammonia, (from liquid receiver) for the saturation of ammonia, during the compression and for the conduit of refrigeration on longer distances. It may be noticed that in this former treatise,” saturated ammonia is recommended for compressor feeding, while, according to the con- 186 clusions of the present treatise, slightly superheated ammonia is not excluded for this purpose. This is explained by the fact that in the present treatise the theoretical and practical indications pointing to certain advantages of superheating in the compression stage have been also considered, while the conclusions of the former treatise were based chiefly on the heat conducting properties of the medium in different states of aggregation. J Generally speaking the differences between these conclusions' ap- pear not to be of very great moment, indeed it may be found difficult to differentiate very closely between them in practical operations. However, the one as well as the other of these conclusions are doubt- less in the direction of greater efficiency in the application of saturated and superheated vapors in refrigeration, and while this paper does not presume to finally discriminate between them, it is hoped that the same will induce properly directed practical tests in order to definitely decide a question which at present it appears impracticable to do on purely theoretical grounds. . . *Different states of ammonia in refri geration” by Dr. J. E. Siebel, in Ice and Refrigeration. December 1906, page 121, etc. . . . . 187 The warmth conduction of pulverous bodies and a new system of warmth isolation based thereon. By Prof. Maryan v. Smoluchowski. The methods of warmth isolation known up to the present time fall into two classes, which, on the one hand, are represented by the old old custom of using converings of finely disseverated materials such as felt, cork, infusorial earth, etc., and on the other hand by the double walled vacuum cells introduced by Dewar. The method in which these latter act is well known; it relies upon the fact that the warmth convection and conduction of the spaces betwenen the walls is, by their vacuation, almost completely "nullified and the warmth radiation of the walls for the greater part negatived by their silver plating. - The action of the first method is, however, less easily to be understood. The materials employed evidently owe their isolating action chiefly to the fact that they hinder the convective streams and the radiation, and this is in agreement with the fact that such materials as exist in most finely disse- verated condition, and whose substance only takes up a small part of the whole volume, possess a conductive power approaching nearly to that of the air ſe. g. hair of mammals k = 0.0000576 (Rubner), feathers k = 0.0000574 (Rubner), cork-powder k = 0.0000728 (Verf). It is quite true that if only tnose circumstances came into consideration the power of warmth conduction of such materials would have to be always greater than that of air alone, since as far as is known all solid (and liquid) massive substances possess a greater power of conduction than the air, and yet there are, as should here be remarked, such materials possessing a smaller power of conduction, as for instance, soot, which is so much the more difficult to understand, seeing that the conductive power of coal is considerably greater [k = 0.01 to 0.0003, Landolt and Bornstj. - The insufficiency of such a manner of explanation is distinctly recog- nisable, however, so soon as such materials are examined in rarified air; then the position of affairs changes entirely, their conductive power sinking 188 to far below that of air. I foresaw, from theoretical reasons which shall be explained lower down, that such phenomena must necessarily appear at lower pressure, and I therefore have undertaken a systematic experimental exami- nation of the conductive powers of powders and other finely disseverated substances in connection with the nature and density of the gas present.) The method employed was analagous to the cooling method most generally used in measuring the warmth conduction of gases. A cylindrical glass vessel into which a thermometer, also cylindrical, fitted served as con- tainer for the substances to be examined. The reciprocal value of the time necessary for cooling the thermometer between two definite temperatures (52.0" and 417") was a measure for the relative power of warmth-conduction of the substance that filled the space between the thermometer and the wall of the vessel. From this the actual value was calculated by comparison with the known conduction coefficients of air [k = 0.0000565 (1 + 0-00213 t) according to Winkelmann, Schwarze and Müller] on the basis of analagous measurements taken with air and with vacuum, to eliminate radiation. The substances that were examined admit of division into granular, powder; consisting of separate massive grains such as: quarz-sand, quarz- powder obtained by grinding it and washing, metal bowder obtained by mechanical pulverisation, Zinc dust obtained by distillation (cleaned in Benzine), rice powder, Lycopode] and powders of «spongyx nature”), consist- ing of bits of undefinable sizes and which themselves are spongy in character, or closely matted, or made up of adhesive smaller grains (such as: soot, Magnesia usta, copperoxide obtained by wet filling, infusorial earth, cork: powder, etc.). As illustration of the very great variety of material for examination only a few characteristic examples can be referred to here, which are graphi- cally represented in Fig. 1. The curves show the dependence of the coeffi- cients of warmth conduction k (*/s cal pro cm” and sec.) on the atmospheric pressure, which latter is given in logarithmic scale, and mean: 1. Quarz- sand (0.26 millimetre grain); 2. Zinc dust (0.028 millimetre grain); Fine Zinc dust (0.0062 millimetre grain): 4. Rice powder (0.003 millimetre grain): 5. Infu- Sorial earth: 6. Lamp black. When discussing the results of the trials it must be remembered that the warmth conduction in powders and such substances is made up of three separate factors: 1. Direct radiation between, neighbouring grains of different tempera- tures: «Radiative conduction”. 2. Conduction by means of the contact of contiguous grains and their substance: «Conduction by contact”. - 1) For numerical data and other details see Anzeiger der Akademie der Wissenschaft“, Krakau, 1910 Mai. (Review of the Academy of Science, Cracow, May, 1910.) 2) Easily distinguishable under the microscope: on tapping with the finger the former fall into a grain heap, while the latter form clumps. 189 3. Conduction between contiguous grains through the gas that fills up the spaces between them : *Gas conduction «. In the case of complete vacuation only the first two factors remain, together with the conduction through the stick of the thermometer which must always be remembered as unknown source of error. Together these usually amount to scarcely 1 per cent. of the warmth conduction noticed by normal pressure. By subtracting this "vacuum conductions from the total warmth conduction we obtain the *gas conduction <, which, under normal 2 K= + OOOO2O 3 -- O'OOO15 4. J. O'OOO1O --- 5 -- OOOOO5 2. —T Zog/o jo = Ol 1 io 1OO 76 O 7x77. Fig. 1, conditions, almost alone comes into consideration, but which regularly de- creases in the case of progressive vacuation. Let us first consider this last factor, the gas conductions. In the first place we notice in its dependence on the gas pressure a distinct difference between the various substances, which is, moreover, also shown in the curves of Fig. 1. General, and exact conformity in this respect is only shown by the granular powders, and moreover, only by those powders which consist of Substances that are themselves good conductors (e. g. metals, quarz),.It is evident that the curves for these powders are similar and can be merged if made to approach each other parallelly along the abscisses axes, that is, that if made to approach they can be expressed by a formula 190 K = f(Ep), where p = atmospheric pressure; fa a common function; E = a characteristic constant in every powder, which constant varies with the size of the grain, in such manner that the smaller the size of the grain the worse Conductor the powder is. These comparisons admit of complete explanation from the standpoint , of our present knowledge of the mechanism of the warmth conduction of gases. Let us first remember the experiments of Stefan, Winkelmann, Kundt and Warburg, Schleiermacher and others, who have proved that, in agreement with the conclusions of the kinetic gas theory of the coefficient of the warmth conduction of gases — at least up to a pressure of Some centimetres, of quicksilver — is independent of the pressure. My own experiments, which were later on confirmed by the work of Gehrcke, have enlarged the district within which the constant of the coefficient of warmth conduction is applicable, to the diminution of the sizes by the hundredth part of a millimetre, and have proved that the reduction of warmth conduction which takes place with vacuation rests upon a peculiar phenomenon, namely the appearance of a «temperature jump” between the surface of the solid body and the adjacent layer of gas which in its effect may also be considered as a kind of resistance to conduction. At the same time I also showed that from the kinetic gas theory such an appearance could be reckoned in advance"). * The flow of warmth passing between two walls facing each other, at a distance 1, of the temperature ti, t, is in consequence of these experiments k (ts—t,) k (t2–t.) 1 : 1 + 2 d tity d, which fixes the conduction restistance, is about equal to the medium way-length of the gas molecules, which it is well known is inversely pro- portional to the gas pressure. A characteristic mark of this phenomenon is thus its dependence upon the dimensions of the vessel; it is all the more not formulated in the usual way , but as , where the quan- + is, or the smaller the dimensions of the space filled with gas are. - s If one now applies these results to the case of a powder, which con- sists of spherical grains of a good conducting substance, it is possible, to deduce theoretically a formula of approximation for its average power of warmth conduction — applicable for small attenuations — (see loc. cit. (An- zeiger der Krakauer Akademie der Wissenschafteng, 1910): k = A ko log (1 + i. #) where a = the radius of the grains, p = the gas pressure, po = the normal pressure, do == the particular value of d, ko = the power of warmth conduc- tion of the gas, and A = a constant dependent upon the arrangement of the grains. noticeable, the smaller *) M. Smoluchowski: Ann, d. Phys. 64, 101, 1898: Wien, Akadem, d. W. Sitzungs- bericht 107, 304, 1898; 108, 5, 1899; Philos. Mag. 46, 192, 1898; Gehrcke: Ann. d. Phys, 2, 102, 1900. 191 With this formula, which, too, really contains the empirically found form k = f(Ep), the measurements conducted upon the spherical grains of zinc dust actually admit of very good demonstration and approximately the results obtained with the other powders of that kind are also reproduced. Here, too, a value arises for d, which actually is about in agreement with the size of the free way-lengths of the gas molecules [for air at atmospherie pressure: do = 1'13. 10-" cm], and also the dependence of the warmth conduction upon the size of grains and the nature of the gas (when using H, CO2) agrees, so far as can be expected considering the sources of error, with that formula. We may well maintain, therefore, that these theoretical condiderations have explained the mechanism of warmth conduction, even as far as such granular powders are considered. We can now, therefore, also understand, in general outline, the phenomena appearing in other cases. If the granutar substance is, in comparison with the gas conductor, no ideal conductor, which, by sufficiently high gas pressure, will be the case with every powder, its influence must make itself visible in a diminution of the warmth conduc- tion under examination. This would, for instance in the case of higher pressure, be noticeable with emery powder, and is noticeable in the cases of Lycopode and Rice powder (see Fig. (1), curve 4 even at lower pressures. The spongy powders must be in some respect analagous [see Fig. (1), cur- ves 5, 6]. Especially do we understand, too, why, for instance, in the case of such loose powders as cork powder and infusorial earth the conductive power changes but little with higher pressure (a little greater than that of air) and the decrease is not very noticeable until comparatively greater rare- faction, since, indeed, the greater the dimensions of the gas filled spaces the greater the vacuation et which the effect of the resistance to conduction appears. The behaviour of soot, mentioned in the beginning, also is explained: the fact that its power of conduction is less than that of the air is simply explainable by its delicate structure and the large number of separating sur- faces between carbon particles and air which produce resistance to conduct- tion. Here is worthy of notice, however, the circumstance which demon- strates the influence of the size of the grains, that with greater vacuation fine metal powders [see also Fig. (1)] become worse conductors than soot, If the rarefaction of the gas is carried so far that the middle length of way of the gas melecules is far greater than the dimensions of the spaces between the powder grains, the application of the previously deduced formula is no longer justified. It is then, however, at once evident, from the stand point of...the kinetic gas theory, that the warmth passing trough the gas must be proportional to the number of the gas molecules that reach the Surfaces of the grains pro second, and therefore to the gas pressure. Actually it is also recognisable in the experiments that the relation of the gas con- 192 duction to the gas pressure approaches to constant values in the case of greater vacuation. - - Let us now consider the conditions that prevail in the case of complete vacuation. I will first give some numerical data by way of illustration. The time taken for the thermometer to cool in the vacuum was 1919 secs., but when the vessel and the thermometer were silver plated — i. e. a Dewar vessel was made -— the time taken to cool rose to 1236 seconds, from which is cvident that the warmth radiation (on account of «restº-radiation, -conduction and the conduction through the stick of the thermometer) an:ounted in the latter case to about 16 per cent, of normal radiation. When the unplated vessel was filled with powder, however, the cooling time ranged from 415 to 2467 seconds according to the sort of powder. Thuis appears the unexpected result that the filling with powder so increases the warmth isolation as to show better results than the Dewar procedure. It is difficult, however, to give exact quantitative data on this and to separate clearly the various cooperative factors. This is especially the case with respect to the conduction through the stick that carries the thermometer vessel. This is not to be ascertained experimentally from our experiments and if we calculate it from the dimensions of the stick and the warmth conductive power of the glass, we get a cooling time which approaches 2467 seconds, the longest time ever observed, so that scarcely anything would remain over for the factors pre- viously described as *radiative conduction « and 2 conduction by contacts, in the best isolating powders. As far as the *radiative conduction& is concerned its calculation is easy in the case of a black granular substance. The radiation of a superficial unit towards an area one degree colder is abouts s = 10−4 (cal. pro sec.). If the powder grains are arranged cubically the difference of temperature of neighbouring layers amounts to d t = 2a, when the fall of temperature is one degree per cm. The quantity of warmth 2 as, therefore, in consequence of inner radiation would pass the section unit, and this would be the value of the xradiative conduction «. If we calculate these quantities we find for example for grains of a size equal to those of the quarz sand used 26 100-, for Lycopode 03.10-%. In the case of Quarz sand this inner radiation may have important effect in the vacuum conduction since quarz is a partial diatherm, on the other hand its influence is very slight with fine powders, especially with glancing metal powders. Regarding the phenomenon described as a conduction by contacts, it is, indeed, possible to foresee that its effect is so much the less according at the grain edges are sharper, or the grain substance harder, or their warmth conductive power slighter, or the pressure of the grains against each other slighter, yet it was from the first hardly to be expected that it could have SO small a value as is apparent from the above data. It may further be re- marked that the effect of mechanical compression can actually be distinctly 193 observed otherwise I would not here refer to this subject, since the ex- periments are not yet brought to completion. - - It is, however, abready apparent from what has been said that in the use of vacuted powders we have found a new procedure for warmth isolation, which is in certain conditions superior to the methods in use up to the present, and which will probably also be of practical value"). In this respect we may draw especial attention to the fact that such warmth isolation has the advantage over the Dewar method, that by increasing the thickness of the intermediate layers (which was only 2.4 millimetres in our experiments) it may be indefinitely improved, while in the Dewar vessels the dimensions of the vacuated spaces are of no consequence. 1) A patent has been applied for in this matter. Lem berg, Physical Institute of the University. 194 New Apparatuses for Determining the Coefficients of the Conduction of Heat. By Friedr. Rud. Metz and A. Behm. Of the many known contrivances and methods for determining the thermal conductivity of matter those will, no doubt, give the most exact results which make use of the electric current for heating the body to be examined, but for such it is necessary to have an electric current of absolutely constant tension. To determine the heat transmission for technical purposes those methods are most generally resorted to which make use of steam for heating, if only because of its being available without trouble or cost. Very exact trans- mission data have already been determined, even for technical purposes, by electrical methods and with an exactitude entirely sufficient, and that could not have been greater considering the variation in moisture content of the insulating or building material examined. Unfortunately what is said as to accuracy of results regarding electrical methods cannot be maintained with regard to steam methods. The accuracy here attained is often very great, but it certainly admits of being much greater. Further, it is inexplicable why, in determining the coefficients of thermal conductivity the very greatest accuracy should not be insisted upon, especially when it is remembered that the coefficients, obtained usually from small experimental objects, when used in technical calculations, are multiplied by large numbers, so that small errors in the coefficients must lead to great deviations from accuracy in the results. The greatest exactitude of methods of comparison is essential in deter- mining the relative values of different competing insulation materials, for in good insulators (with 80% efficiency) the coefficients only admit of a correct comparison if they are determined with the greatest accuracy, otherwise it may easily happen that the errors in one and the same measurement become greater than the difference between the figures giving the conduction of heat. The fact that only the most exact experimental results are of technical value, and the recognition that this accuracy was not always obtainable with the steam heat hitherto applied led to such improvements and alterations in 195 these methods as, considering the condition of the materials to be examined, made it possible to obtain measurements of such materials with an exacti- tude at least equal to that mentioned above as an advantage of the electrical methods. - Before we describe these new experimental methods and apparatuses, it is necessary, from a physical point of view, to critically examine the factors which have a determining influence in each determination of coefficients of heat transmission, and especially is the application of condensation methods. In nearly all methods the measurement of the amount of transmission is effected by determining the quantity of heat that has passed through the object under investigation per unit of time, of surface, of thickness, and of change in temperature. If we consider how many factors influence each of the quantities to be measured, and how many factors regulate and change the heat-technical state of an insulating material we shall appreciate that generally valid comparative values are only attainable if the influence of each factor upon the final result is determined with the greatest possible accuracy. In the course of the following paper we will scrutinize a number of these factors as regards their influence upon the methods and upon the material under investigation, but first we will describe our new apparatuses. The principle of our apparatuses, like that of the generally known steam apparatuses, rests upon the calculation of the loss of heat in the usual manner from the condensation water formed. Through the peculiar construction of our apparatuses, however, some sources of error are avoided which existed in the old apparatuses. Our tubular apparatus Fig. 1, which is used to examine insulating materials for steam conduits, consists of an iron tube through which saturated steam passes. The pressure is either kept constant by means of a Käferl reducing valve or else the steam passes through the ap- paratus out into the atmosphere, if it is desired to attain a steam tempe- rature of about 100 degrees. The steam is separated from moisture in a separator, before entering the apparatus. The apparatus is divided into com- partments by two discs welded in at some distance from their ends, and these compartments are connected by U shaped bent tubes which per- forate the discs. These discs serve a double purpose : they serve to further dry the steam before it enters the experimental body proper, situated be- tween the two discs; but, primarily, they serve to gain such results from the apparatus, the whole length of which is covered with the experimental material that these results may give values like those that would be obtained if the trial were made with an endless insulation. As, namely, the insulation of the apparatus stretches over all three compartments, and only the conden- sation water forming in the inner compartment is measured, the two ends of the apparatus cannot, through their loss of heat, influence the result, be- cause the condensation water is led off separately and the two outer steam compartments insulate the inner one absolutely against any loss of heat at its ends, for they are filled with steam of the same temperature. So, too, 13% 196 the insulating material under experiment extending over the two outer compartments protects the material against loss of heat that usually takes place at the ends of an insulation. The condensation water conduit from the trial compartment, and the collecting vessel are also insulated by a steam • Isaxºfºice. l e O == –, e–, e–se, a - *-* * *= <= * * * = * * *-* = ** --- * * * = ** = ** = = * * = ** * = - O deo &n awałeſ. © i O ©oxºſºvº 20ww.LeCºlahoa Mººn, , | begºsº | ..! * il 293 waſ ºvo | © W. O O º -- © e e i Q •) • \ ZS 2S % %S ZS * ŽS. - 4. Sº?/ º- - - &S ŽSežS. % £, At- º Fig. 1. jacket, so that the quantity of water condensed in the trial compartment is exactly the same as that which has passed through the insulated section under examination. Since besides moulded insulations, granulated and pow- dered substances, frequently used in building operations, also need to be 197 tested, we are making a second apparatus built on the same principle and having the following construction. A square frame of flat iron is welded exactly on to the centre of the under surface of a square wrought iron plate. To this frame a water tight tin vessel is fixed whose four sides are drawn together to a point. The condensation water forming within the frame on the iron plate collects in the funnel shaped tin vessel and flows through a cock into a cooler. This cooler is so arranged that with continual flowing off of the condensation water the water level can never sink below the mark shown in the sketch. If smaller quantities of condensation water are formed, the cooler can be dispensed with and it suffices to let the condensation water drip into the collector from a U shaped bent tube in such a manner that no evapo- ration loss is possible. The funnel shaped tin vessel is enclosed in a second such vessel which serves to form an insulating steam jacket. As the inner tin vessel is thus protected against any loss of heat and the water level is always up to the mark within the steam jacket, the condensation water measured can only have formed on the square experimental surface within the flat iron ring and consequently it must correspond exactly to the quan- tity of heat that during the time has passed through an equally large piece of the insulating material being tested. The outer steam jacket, here again, as in the tubular apparatus, ensures that the insulating material being tested is under exactly the same thermal conditions as its surroundings. A tin vessel, diagramatically shown in the sketch and whose lower surface is kept at an even temperature by means of flowing water or melting ice, serves to keep the temperature of the outer surface of the insulating material being tested constant. The whole apparatus is so fitted that the experimental object can be tested in horizontal or vertical position, because such tests are necessary with air spaces, or combinations with such. In vertical position the condensation water conduit is reversed by means of a cock and the insulation is transposed. The steam supply to and from the inner compart- ment are such that the water drawn in cannot influence the result. If coefficients at temperatures above 100 degrees are to be determined by this apparatus, it will have to be strengthened for the increased steam pressure, and the insulation must be replaced by one like that on the tubular apparatus. The determination of the temperature is effected in both apparatuses with the aid of thermo-cells which are attached to the steam heated surfaces or to the water vessel, they may also be attached at many other points on the surface of the insulating material being tested. The apparatuses require no other attention during the experiments than that the temperatures are read of. At the end of several hours’ experiment the condensation water formed is let off and weighed. This is a short description of the apparatus; further details may be learned from the accompanying sketches. More exact con- sideration is of no great interest here. 198 In the following we will thoroughly criticise the methods of the various apparatuses, in order to see how great exactitude may be attained therewith and to ascertain their advantages and weak points. Our method presupposes that the condensation water measured corresponds exactly with the amount of heat that has passed through a definite piece of the insulation to be examined. It will be noted that such can only be the case if during the whole experiment all the temperatures of the experimental apparatus and the object under experiment are constant, for with every change of temperature heat will be given off or absorbed either by the apparatus or by the experimental object, which must necessarily end in the result obtained being either too large or too small. Such constancy of temperature is natu- Jhaw-cove/Gen. QX *::::::::::::: *chººlſ, rally only attainable if care is taken that the outer surface of the experi- mental object always has the same surface temperature; and this can only be secured by artificial means, such as melting ice, flowing water, etc. From this it is also plain that if in the tubular apparatus several measurements are made one after another at different steam pressures, a new measurement must only be commenced when the temperature is again in a constant state. The measurement of temperature, as already mentioned, is effected with thermo-cells, for only with these are such temperature measurements possible as are necessary for determining the result. The thermo-cells them- selves consist of Constantan and copper; they are not tabulated but the temperatures are given by the zero method, which offers the advantage of invariably exact temperature measurements even at the highest tempera- 199 tures. In placing the thermo-cells great care must be taken that they lie in sufficient lengths, on surfaces of the same temperature, for otherwise large errors may arise through heat transmission through the thermo-cell itself, especially if there exists a high temperature gradient per 1 cm. In consideration of the exactitude of result always attainable in such measu- rements the temperature measurements need not be too exact so that it is quite sufficient to take the temperature to — 19 C. In the following we will examine with what exactitude the heat emission may be determined by measuring the condensation water. As a dis- advantage of this method may be mentioned: that the steam takes moisture along with it. This may be met by suitable moisture separation. That some moisture in the form of the finest mist will be carried into the middle of the experimental compartment of the apparatus, is unavoidable, yet it may be accepted that with a constant supply and outlet of steam just as much moisture will be carried out of the compartment. Certainly a noticeable error is not likely to arise in our apparatus through moisture drawn in by the steam. Another source of error also resulting from this kind of measurement is the adhering of the condensation water to the walls and the uneven dripping and flowing of the condensation water to the measurement vessel. This source of error requires that the experiment be as long as possible (10 hours), for only thus is it possible, especially with small hourly transmission of heat, that uneven flow to the collector may be eliminated. Further it is of the greatest importance that the apparatus be protected against every mechanical shaking, for such in some circumstances is also liable to effect great fluctuations in the flow of the condensation water, in short experiments. If the points mentioned are respected this kind of measurement of the heat transmission offers an entirely sufficient exactitude. The sources of error just mentioned may also be considerably lessened by giving the condensation. surfaces the necessary inclination and, with good insulating materials, by caring for plentiful formation of condensation water by testing thinner layers. Further in order to avoid any loss of condensation water through evaporation during weighing, it is cooled to room temperature while being let out from the collector. As the condensation water remains throughout the experiment in a vessel insulated by steam, loss by evaporation during the experiment is also impossible. In long experiments larger quantities of water are also obtained, and by this any error due to retention of water in the collector is so far reduced that this factor cannot enter noticeably into the final result. Another source of error may lie in the possibility that water flowing into the collector while the condensation water is being let out may not be correctly measured. To avoid both the following process is made use of. The collector ends in a water gauge glass of small section also insulated by steam and bearing a mark. At the commencement of the experiment the water from the collector is let out until below the mark. The experiment commences 200 at the moment when the water, rising, reaches the mark. The experiment ends when, on emptying the collector, which again takes place at first, until below the mark, the water level, again-rising, reaches the mark. If all the above mentioned points are duly observed the sources of error named will certainly be so reduced as to prevent their having any noticeable influence upon the final result. If we now consider the advan- tages resulting from the use of steam in such experiments the greatest will be the exact equality of temperature throughout the experimental tube. A further advantage as compared with electrical methods lies in the fact that under the circumstances condensation water forms on the slightest reduction of temperature, so that any change of temp. must show itself by increased or decreased formation of condensation water. Such variations are, in electrically heated apparatuses, only noticeable in the altered temperatures, whereas in our case there is a double check, on the one hand change in the quantity of condensation water formed, and on the other hand altered temperature. The fact of the heat bearer being steam in our trials offers, moreover, no disadvantages as compared with electrical trials, where the heat transmission takes place by radiation and by air current and conduction, because in our apparatus it is impossible that parts of the heated bodies have temperatures not consonant with their surroundings. Such may be the case in electrical apparatuses, however, if the fittings are not good. A special advantage of our method, in the examination of insulating material for steam conduits, lies in the fact that in the tubular apparatus all condi- tions are present that the insulating material would be subject to in prac- tice. A retrospect shows us that measurement of the heat transmission by means of condensation water can be effected with entirely sufficient exacti- tude, and that the method is in no way less exact than the electrical method, so long as the safety regulations are strictly observed. As before mentioned our method, like all, such, rests upon the assumption that the condensation water measured corresponds exactly to the quantity of heat that has passed through a certain piece of the material tested. This can, naturally, only be the case if the steam in the middle compartment only can form condensation water if it lose heat by transmission through the insulating material, so that any loss of heat by other means is impossible. That this is actually the case is due to the two outer steam compartments, and the steam insulation of the condensation water apartment and of the collector. The same cannot always be said of steam methods hitherto followed. The existence of the three steam compartments and the fact that the experimental object extends over all steam compartments enable the measurement of the heat trans- mission, which takes place only through the insulation over the middle compartment to be effected with exactly the same result as if the trial had been ma with an endless conduit, for all possibility of loss of heat at the ends is minated by the adjoining parts of the insulation material being under e ctly the same conditions as the section under experiment. The 201 same results are attained with the plate apparatus as, here, the results. obtained are also such as if determined with endless surfaces. Without doubt a limit to the thickness of the experimental bodies is fixed by the dimensions of the apparatus, i. e., in both apparatuses, the thickness of the experimental bodies may not be so great that the end pieces have no effect on them. If, however, it is necessary for technical reasons to exceed this thickness, then the dimensionss of the apparatus must be suitably increased. --- - In the following we will discuss in detail the purely external factors, not inherent in the apparatus, which nevertheless influence the results of trials with the tubular apparatus, but which are eliminated in the plate apparatus by the presence of a cooling vessel with flowing water. That a constant temperature is not also artificially obtained by the tubular apparatus on the surface of the material under experiment is established and we will now more closely examine into the reasons for this. The tubular apparatus chiefly serves two kinds of experiments; the one to make comparative experiments with various insulating materials; the other, to determine the absolute loss of heat occurring in practice with insulated steam conduits For relative trials it is certainly desirable to artificially keep the surface temperature of the material under experiment constant. The use of water jackets, etc., etc., over the tubular apparatus offer, however, great difficulties and they are therefore dispensed with. Consequently relative trials made with the tubular apparatus are not so exact as those made with the plate apparatus. - The numerous trials made in practice with the old steam apparatuses, however, have proved that the results of trials with the tubular apparatus on experimental objects that differ widely in their heat insulating powers furnish values that are very useful. Thus we have seen that the tubular apparatus can only serve for the most part to determine the effective value of insulating materials; it does not furnish for these very exact coefficients of heat transmission, those furnished by the tablet apparatus and the appa- ratus with artificially constant temperature gradients are more exact. It is well known that the effective value of an insulation is determined by com- paring the quantity of heat lost per unit of surface and of time by a non- insulated tube with that lost per hour by the unit of surface after insulation with the experimental material, it being assumed that the steam pressure is the same in both cases. That such experiments, eo ipso, cannot produce very exact results we shall soon perceive, in the further course of this dis- cussion, but it is a fact, in spite of this, that they possess just as great, if not even greater, technical importance as the absolute determination of the coefficients of heat transmission. - A very large number of factors have influence on the results of these trials. We have already mentioned that, in determining the effective value, the loss of heat of the insulated must be compared with the loss of heat 202 --- of the non-insulated tube. Upon what, however, does the latter depend? Chiefly, certainly, upon the surface temperature, but also upon the con- dition of the surface, — whether it is smooth or rough, whether it is of cast iron, copper, wrought iron etc. — for these factors are calculated to influ- ence the amount of surface radiation. As a tube, however, not only gives off heat but also absorbs heat, objects near to the experimental object, if they give off great heat (stoves, steam heating) can influence the result by decreasing the loss of heat of the bare tube. But the surrounding air also absorbs heat, and that in two ways, by conduction and by convection. The amount absorbed by convection depends, naturally upon the rate of motion and temperature of the moving air. Such motion, however, arises even from the heating of the air on the tube itself, and the amount of motion is here a function of the space and dimension as also of the position of the steam tube in the room, and of the surface temperature of the tube. The quantity of heat absorbed from the tube by the surrounding air is inconsiderable in comparison with that absorbed by the ever present air current. I will not tire by recounting further factors, those already mentioned will fully suffice to show that the amounts of heat given off by a tube of definite surface temperature and condition will not be constant even if the examination be made in different rooms having the same air temperature. From this, how- ever, it is evident that it is absolutely necessary, when stating the results of such experiments, to give data which shall make it possible to reach con- clusion, based so far as possible upon the influence that all these factors had on the result of the experiments. It is also necessary to state the dimensions of the room in which the experiment was conducted, the posi- tion of the experimental object in the room and any sources of extraneous heat present. The air temperature in various parts of the room must be known, as also the air motion near the tube, and all factors that are calculated in any way to influence the results of the experiments. It is plain that such determinations made with various apparatuses in various places can only roughly agree. Exactly the same factors as those calculated to influence the heat radiation from the bare tube influence the heat radiation from the insulated tube. From the nature of many factors it is evident that their in- fluence is greater in the first case than in the second. For instance, the air motion over the bare tube is, under similar conditions to those here, simply a function of the surface temperature. But the surface temperature of the bare tube is very different to that of the insulated tube. Therefore, the amount of heat radiated from the insulated tube, in spite of the same temperature difference between air and steam, must be variable, especially if determined at different places with different apparatuses. Though a large number of other examples might be cited in support of this assertion, I will again forego tiresome explanation. In all the above cases we have seen that the determination of the effective value of an insulation according to the methods described only possesses strict validity for the experimental 203 room and apparatus, and that the application of such determinations to other conditions and rooms cannot be made without further investigation if absolute exactitude of value is important. Frequent repetition of such trials under different conditions enables it to be easily seen how large are the variations to which the efficiency is subject owing to the above reasons. Our tubular apparatus was made transportable in order that the efficieny of the same insulation material might be determined at various places, and in buildings and open places without difficulty. If I have dilated upon this point more fully than was apparently necessary, I did so for a special reason. So long, namely, as we make use of efficiencies so obtained for technical calculation we shall make no great errors, provided that the above mentioned factors do not possess quite other dimensions in practice than in the experiments. Should this be the case it is still possible by a sensible correction of the efficiency to allow for the changed factors. It is quite a different matter, however, when such data regarding efficiency are used to compare two different competing insulating materials. If the efficiencies are determined with various apparatuses at various places and perhaps too, at various temperatures, then the error made in such comparison may, as already stated be far greater than the difference in the actual insulating values of the two materials. Indeed this can go so far that the material for which the smaller efficiency is found may possess the better insulating quality. If it is not possible, when determining the efficiency, to allow for the value of individual factors that every uncertainty of result is overcome, much less can the influence of these factors be allowed for in determining the efficiency of an insulation from the coefficients of its heat transmission, and, consequently, efficiencies obtained on computation basis even with exact coefficients of heat transmission must have far greater errors than exist in the particular efficiencies. In recounting these factors I have, for special reasons, only mentioned those which arise from the method or the apparatus. If, however, most of the factors mentioned here are eliminated by artificial obtention of a constant temperature gradient, there yet remain a large number of such factors whose value it is absolutely necessary to know if it is desired to obtain exact results. We have seen that efficiencies can only be determined and not calculated exactly and that if the most exact possible results are desired, the conditions of the particular case must be imitated as closely as possible, for example, in the case of an out-door conduit, experimental apparatus in the open air (rain, wind, etc.). We have also recognized that exact comparisons between the values of different insulating materials can only be made on the basis of the coef- ficients of their heat transmitting powers. Before we proceed, however, to more closely consider the requisite apparatuses and methods, we must not omit to mention that in determining the efficiencies, if a determination of the influence of individual factors is simultaneously undertaken, the foundation 204 can be laid upon which it might, perhaps, be possible in the future, with the aid of correct coefficients of thermal transmission, to calculate the efficiencies of insulations more exactly than heretofore. tºº-º-º-º-º-º-º-º-º-º Determination of coefficients of the conduction of heat. For the determination of the coefficients of the conduction of heat with the plate apparatus, nearly all the above mentioned factors, as already remarked, are eliminated by the cooling vessel, in so far as we have not to do with the examination of air spaces. Although the experimental object is under a fixed, unchanging temperature throughout the whole experiment, yet there are quite a number of factors, not in the method and apparatus, which must be known if the results obtained are to be reliable. Many of the factors to be mentioned will certainly appear as a self-evident requirement of every thermal examination, and yet it will be noticed that in many experiments such factors are missing, even possibly that allowance for them is neglected. Considering the porous nature of almost all insulating materials, it is necessary that their volumetrical weight be given. If the specific weight can also be given, it will be an advantage. That either only absolutely dry bodies be examined or that the moisture content of the material under experiment be stated, is made necessary by the great influence that the water content in many materials has on their power of thermal transmission. With materials that possess a definite structure like wood or that have empty spaces like hollow bricks the thermal conductivity is often not the same in every direction, therefore the direction of thermal transmission must always be stated with Such bodies. In examining air spaces the direction of thermal transmission is also of effect, and both the position of the air-spaces in the hollows (horizontal, vertical) and the direction of thermal transmission (upward, downward) must be known, otherwise such experiments are valueless. If these rules are observed values will be obtained that admit of quite general comparison, in so far, that is, as the changing State of the material examined does not of itself involve great uncertainty of result. The determination of the coef- ficients of the conduction of heat by the plate apparatus is a perfectly simple and easy matter, and yet gives values of entirely sufficient. exactitude. The heat retarding value of an insulator is, however, not the only quantity essential for its applicability, for besides the property of being a good insulator other demands must be made of an insulating material. I will not enumerate them all, but merely mention stability, light weight, strength, durability, indifferences to chemicals etc. etc. From this, however, it is evident that if finished insulations and not insulating materials merely are examined, other data are required if an exact economical comparison with other insulations is to be carried out. In examining insulations one must not artificially create 205. other conditions than those to which they will be subjected later on in practice. Above all, for instance, insulations of ice conduits must not be examined at other temperatures than occur in working, they must not be placed on a steam pipe. This requirement is, from a thermo-technical point of view, already caused by the fact that the coefficient of the conduction of heat is a function of the temperature. Further the weight of insulation per metre of length must be known, since the loading of steam conduits with the insulating material posesses technical importance. In giving the strength of an insulator it in no way suffices to state, for example, that it consists of cups of this or that strength; it is necessary always to give the actual strength of the whole insulator. So, too, the insulating value, which, for instance, a cup formed insulating material has in fixed state is always greater than that corresponding to the heat transmission through the cups as in consequence of the mounting air spaces, top Smearing, bottom smearing paint, etc. the heat transmission is decreased. Besides these data all those changes must be mentioned which the insulation itself suffers during the experiment; for instance, carbonisation, tearing, splitting, and such like, for all these factors must be known, if it is desired to obtain the real economical value of the insulation. Here again it is seen that the insulation material must be subject to the same temperatures and conditions during the experiments :as in actual practice. With insulating material whose separate parts are not of the same consistency, it is self-evidently necessary that the experiment be made with material so chosen that the result represents a medium value. The above statements have shown that the efficiency of insulating material vary with conditions and place of experiment, and, being also influenced by many important factors, may be determined with the aid of relatively simple apparatuses. These statements also show how indisputable thermo-transmission figures may be obtained. They have enabled us to perceive, too, that a statement of these two quantities alone is of but slight practical value and that they only attain to full technical value when besides the two principal quantities the additional determining factors are also given, according to their importance. For only on the basis of such data may the technician know the real economical value of insulation, or ibe able to make calculations of practical use, and to critically compare various insulating materials. 206 The Efficiency of Various Methods of Insulating Refrigerated Rooms. Experiments on thermal conductivity. R. Biquard, Head of the Physics Section of the testing laboratory of the Conservatoires des Arts et Métiers. In all refrigeration work, the walls have to fill, besides their mechani- cal function in the building, that of barriers opposed to the passage of heat. On their efficiency from this point of view the greater part of the completeness of the refrigerating installation often depends. - Nevertheless, there is always a limit beyond which the economy in cold, effected annually by reinforced insulation, does not compensate for the interest on, and the amortisation of the capital expended. * It is, therefore, of special importance to be able to calculate beforehand the efficiency of a given kind of wall. This efficiency depends upon two absolutely distinct factors, each of which must be reckoned with separately. *. 1. The transmission of heat through the material of which the wall is composed. - 2. The transmission of the heat by the surrounding medium to the surface of the wall, or vice versa. º Two coefficients must therefore be determined for a given kind of wall. 1. The coefficient of conductivity (C), numerically expressed in practice as the quantity of heat (in calories) which passes through 1 sq. metre of a surface of a material, which is supposed indefinite, for a difference of 1° C. per 1 metre of thickness. 2. The coefficient of surface transmission (k), numerically expressed as the quantity of heat received or lost by 1 sq. metre of the surface of this material, and for a difference of 1° C. between the temperature of the sur- face and that of the immediately surrounding air. We shall see further on that, in the case of this second coefficient, it is necessary to state the form and position of the surface. -- 2O7 Transmission of heat through a solid wall. The quantity of heat Q which passes through a solid wall, when the temperatures T and t of its two surfaces (and not those of the surrounding atmosphere) are known, may be represented by the formula: o-ºº-oor o-s(#) e C (where S = the surface of the wall, e its thickness, C the coefficient of conductivity for the material). --- But it must be explained that this formula assumes that the tempera- tures T and t of the surfaces of the partition are known temperatures that may differ very appreciable from those of surrounding media, and which are obtained for instance by placing a small thermo-electric couple in a cavity as near as possible to the surface. In practice only the temperatures t and 0 of the media separated by the wall are known, and the well-known formula, which theoretically repre- sents the quantity of heat transmitted, then becomes: (t—6) S where k and k are the coffiecients of surface transmission of the two sur- faces of the wall, to the surrounding atmosphere. This formula may be represented, especially the introduction of the 1 1 -- term S k and k’ by saying that each of the two surfaces of a partition act as a supplementary insulating layer, whose thickness is unity (1 metre), and whose coefficient of conductivity equals the coefficient of surface transmis- sion of the surface being considered. This explains the fact that, by doubling the thickness of a stone wall 0.30 metres thick, its insulating efficiency is only increased by about 30% of its original value, because the insulating effect of the surfaces remains the same. But if, on the other hand, a second wall 0°30 metres in thickness, is placed parallel to the first, and separated from it by a space of some centi- metres, it can be seen that the efficiency is really doubled, because the number of surfaces are also doubled. The following table gives some idea of the importance of the insula- ting effect of surfaces in different cases. 208 h The propor- Value of | º: of ºin, * ë 1 Value of Value of .. .- The variety of wall Thickness H---- e * + 2. faces, to the # + + C * ' * |insulating ef. ºf fect of the whole some will ‘20 2.89 *111 346 | 68-09ſ, = 18 30 2:49 166. '401 59.0% R → Rºss *40 2°18 *222 '457 || 51.0% -- *. '60 1.76 “333 '568 41'09/o U ‘90 1°34 ‘500 ‘735 | 32.0% f ‘O3 1-2 '6 '835 28.0°ſ, Panals of con- ‘O5 ‘81 1:O 1-235 19:09/. glomerated cork ‘10 '45 2-0 2-235 10:59/o C = 05 { • 15 *31 3-0 3:235 7.09/o R = 8'5 ‘2O “235. 4-0 4'235 5.5% || 25 *191 5:0 5235 | 4.5% Ordinary glass ‘O3 3:45 ‘004 ‘290 99.0%, C = 0.8 R = 7 * It can be seen, then, from the action of the surfaces, that the insul- ating effect of a wall does not increase in the ratio of its thickness, that is. assuming that the coefficient of conductivity of insulating materials depends upon its thickness. As a matter of fact the insulating effect of a wall for unity thickness and surface, is variable for each thickness, but it does not necessarily follow from this that the internal coefficient of conductivity, or specific conductivity of the material, varies. Moreover, the experiments. which we have made with the apparatus described further on, in order to: determine these coefficients, have shown that the conductivity is independent of the thickness, for thicknesses between '04 metres and 20 metres, in . the case of the conglomerated cork on which our experiments were car- ried out. It should be observed, moreover, that contrary to a somewhat generally: accepted idea, it is especially in the case of poor insulations that the exact ratio does not exist. The table given above shows that if the insulating effect of the surfaces is as much as half the total effect of a stone - wall: ‘40 metres thick, it is not more than "/so” of the effect of a layer of cork: 20 metres thick, and hence only an insignificant deviation, from the exact; ratio is found here. 209. Hence, in refrigeration construction, where the walls often have an in- sulating effect at least equal to 0.20 metres of cork, we are not far from the truth in assuming, in a first approximation, that the insulation is pro- portional to the thickness of the material. * Determination of the coefficients of conductivity of insulating materials. The majority of the old methods of measuring coefficients of con- ducting (glass boxes, heated cylinders etc.) allows of obtaining only relative results. Two methods have recently been proposed for determining absolute coefficients; the first, due to Nüsselt, which uses a hollow sphere made from the material to be experimented upon, whose central cavity receives heat in the form of electrical energy heating a resistance; the Second, due to Desvignes, which measures the fall in temperature through a thin insulating disk, warmed on its lower surface by a steam stove. This last method, which is very simple in practice, does not, unfortunately, give a choice of temperatures, which is especially inconvenient as the coefficient varies very appreciably between 100° C., which is the temperature in the experiment and 0° C., the temperature in practice. The Nüsselt sphere method only applies to granulated or fibrous materials, but it has been modified by its inventor so as to be applied to hard materials such as stone, by using a hollow cube, the walls of which are formed of the material to be tested. We have sought toº establish a simple method of testing which could, according to a resolution passed at the first Refrigeration Congress in 1908, be applied to all current materials, granulated or solid, or even to walls. having air spaces; and under the conditions of the practical use of insula- ting materials, that is to say, for temperatures varying between 0° C. and 30° C. or 50° C., and for thickness between 10 and 20 centimetres. We relied on the guard ring process to insure the normal transmission of heat through an insulating wall, a method already employed in another form by Berget in measuring the conductivity of metals. We also measured the quantity of heat transmitted by using it to melt ice, the water being collected and weighed. The apparatus which we set up at the laboratory of le Conservatoire des Arts et Métiers is as follows: The insulating partition, or the material Fig. 1 to be tested, is placed between two copper plates, one of which is kept at 0° C. by ice, and the other at a given constant temperature by a current of water circulating in the space A B C D. *. The quantity of heat measured is that which is transmitted through a b, the centre of which is so far from the sides that their influence may be practically eliminated. For this reason the centre of the copper plate 14 210 g h is separated by a space r r on either side of which are the walls a c, b d, and a c', b’ d’ enclosing the ice boxes a b c d and e fgh. The spaces a a' and b bº are filled with cork. The tubes tº and tº serve to col- lect the water of fusion coming from the interior and exterior boxes. The temperatures of different points on the insulation being tested are given by copper-constantan couples, 0.3 m. dia. imbedded in the sur- face or separated in the interior of the mass. Lastly the whole apparatus is enclosed in a thick insulating covering to avoid excessive consumption of ice. 2 *, Wºº & O $º ‘S Li 2 p → ~) s p 3-ºx Y & -N () -a X X * . . . . 12 285 x '0495 X. 053 X) •0585 X X X * . . . . “15 275 x -049 X) '053 X) •058 The same after 20 days immersion in * Water . . . . . . . . . • • . . ‘18 310 x }> ‘O73 X ‘O78 X) Corrugated packing cardboard (thickness - g of each layer 005) 35 layers . . . '175 X ‘O48 ‘O52 ‘O54 '060 Flooring of hollow bricks 2.5 cm. bricks with spaces of 2.5 cms, separated by an air space of 11 cms. (Fig. 2) . . . --- * -- '59 between 20 and 22° C. Flooring of hollow bricks 2.5 cms. with spaces of 8 cms. Layer of concrete 3 cms. Air space 13 cms. (Fig. 4) . . || — * *m. '58 between 19 and 23° C. The same with the sir space filled with concrete (Fig. 3) . . . . . . . . . **** &= -º-; – ’ 1-02 between 2° and 21° C. 213 (kiesergühr, flax, silk, wool and cork), the coefficients of conductivity increase in proportion to the temperature. f 1 At ordinary temperatures this increase is about 273 Per degree Centi- grade. - The tests which we have carried out on different kinds of compressed cork have been practically in accordance with these conclusions as concerns the amount of the variation, as is shown by the table which we have just given. The figure # should only be considered as approximate, and we have stated that for corrugated cardboard, for instance, the increase is much more rapid, without doubt by reason of the circulation of the air which it contains. g Nevertheless in the practice of refrigeration, where differences in tem- perature of more than 40° C. (–5° to 35° C) are rarely met with, the variation in the mean temperature of a partition can hardly exceed 15° or 20° C., or a maximum variation of 7% in the coefficient of conductivity. . It is, therefore, sufficient in the characterization of insulating materials to adopt a uniform difference in temperature, 0° to 30° C. for instance, for which the average conductivity of each material is defined. Relative coeffi- 'cients would thus be obtained for all materials, and the transmission could then be calculated with an approximation of at least 2 or 3%. Moreover, in an insulation project where the mean temperature varied from 15° C., a small correction could be made by adopting Nüsselt’s coeffi- scient, or those which may subsequently be found for each material. As far as the influence of density is concerned, the results of tests are far too few to lead to any general law. *-. Nüsselt's and Gröbers experiments have shown that in the case of flax the conductivity increases very rapidly with the density, between 380 and 700 kilogrammes per cubic metre, as is shown by the following figures. Density per cubic metre . . 383 kg 470 kg 579 kg 702 kg Conductivity at 0° C. . . . ‘O95 ’131 17O *201 Nevertheless, there exists for this material a low density limit, below which the conductivity ceases to decrease, and begins to increase again. Otherwise it would be possible to obtain almost absolute insulation with an infinitesimal quantity of material. On the other hand, comparing the results which we have obtained with conglomerated cork, using either rosin or caseine, the density of one being practically double the density of the other, it is found that this great increase in the density does not produce any greater increase than 18% in the conductivity. It is true that these materials have different substances to hold them together, Summing up, it may be seen that, if it is possible to say that the conductivity grows with the density, it is not possible to fix the amount of variation for all the ordinary materials. 214 We shall pursue this subject further by a series of experiments in the physical section of the testing laboratory. Lastly, as concerns humidity, an idea of the influence it can have may be obtained from the results of tests we have carried out on two kinds of cork, first when dry, and then after 20 days immersion in water. These results, indicated in the table which we havegiven, may be considered as being obtained with samples Saturated in water. For cork held together by caseine, the density and conductivity are practically doubled. For cork held together by rosin the density is only increased by 12%, and the conducti- vity by 45%. - These results will also be followed up at the testing laboratory by the experiments on which we are engaged. Transmission of heat from solid surfaces to the air. A knowledge of the coefficients of transmission of heat to the air from solid surfaces is particularly important in calculation dealing with losses of heat through windows and stone walls of houses. As a matter of fact we have just seen that the larger part of the insulating value of such partitions is due to the obstacle which the heat encounters in passing from a solid to a gaseous medium, or vice versa. Tables have been made out which set forth these coefficients, and which give, in the case of certain kinds of partitions, the quantity of heat transmitted per square metre per hour for a difference in temperature of 1° C. between the media separated by the wall. (See the report of the First International Congress of Refrigeration pages 539 to 548, Volume 2). In refrigeration work the partitions either consist of, or are covered with good thicknesses of materials which are strong insulators by themselves. The insulating effect of the surfaces then only comes in as a very small 10 20 of insulation containing air spaces as we shall see further on. Moreover, the surface insulating effect is not, like the thermal conduc- tivity of solid materials, a constant specific value for each material. The transmission of heat on the surface of a body takes place (1) by radiation, (2) by conduction and convection, that is to say by the movement of the air itself. These movements depend upon the state of agitation of the atmosphere, and upon the facility with which convection currents can be set up along the surface. Hence the form, position and size of the surface has some influence. In practice, even when the radiation and convection are not exactly proportional to the difference in temperature between the surface and the air, when these differences are small (less than 10° C), the simple law of surface transmission can be assumed : º 1 1. --- wº º * fraction ſº to − Or es) of the total insulating effect, except in the case 215 Q = K S (t—T) where Q represents the heat transmitted, K X. * coefficient of transmission of the surface of the partition, t > » temperature of the air, T X). » the temperature of the surface of the partition. For the second surface of the partition it would be similar Q = K’S (T-6). From these two equations with the formula for transmission in the interior of the partition we obtain CS Q = Teſ (T-t) leading to the well known equation: *: S (t—6) Q = 1 1 e k + k’ + C which permits calculating the effectiveness of an insulating partition. The coefficients k and k’ may be considered as being each composed of two terms, one of which R represents the radiation and the other f theconvection. The most recent determinations of the value of R are due to Wamsler and Nüsselt (Munich 1908—1909). They showed that the greater number of bodies having a dull surface have a coefficient of radiation R very near to that of bodies having their surfaces blackened by smoke, while polished metals have a much lower coefficient. These results had already been ob- tained by Peclet. The following figures give the value of R for several common mate- rials according to Wamsler. R. Polished Copper . . . . . . . . . . . . . . . 0.79 Polished Iron . . . . . . . . . . . . . . . 1.33 Oxidised Iron . . . . . . . . . . . . . . . 4.40 Beech Wood . . . . . . . . . . . . . . . . 4.48 Lime Mortar . . . . . . . . . . . . . . . . 4.30 Lamp Black . . . . . . . . . . . . . . . . 4.44 Concerning convection, the values of f are little known, they appear to depend, not upon the nature of the surface, but only on its size, shape, and position, and upon the movement of the air, if it is agitated. Peclet assumed 4 to 5 as the value of f. Nüsselt found in various ex- periments and for small differences in temperature f=3 + 0.08 (t–0) f = 25 in an atmosphere moving at the rate of 3 metres per second. in a calm atmosphere, and 216 These data are still very incomplete and numerous experiments will be necessary. It may be seen therefore, that it is very advantageous from the point of view of insulation to use surface coatings having a small coefficient of radi- ation; it would, then, be a good thing to study different kinds of paint for this purpose. The use of air spaces for insulation. – Effectiveness. – Depth required. It has long been known that, if one or several air spaces are made in a partition, whose depth is added to that of the solid matter, the insulating. power of the whole is increased. * This effect is easily explained, because we have seen that in a solid partition each surface separating the surrounding air acts as a supple- mentray layer of insulation. The introduction of air spaces has the effect of multiplying these imaginary layers, each air space introducing two mores of these. t It is advantageous therefore in practice to provide the greatest number of air spaces consistent with the solidity and durability of the partition. But it is necessary to find out the best depth to give to these spaces, and besides to avoid adding the air spaces to the partition, but to substitute them for part of the insulating material. In a layer of air separating two solid partitions, the heat is transmitted by radiation from the surfaces and by conduction through the air itself. In theory, transmission by radiation is practically indepedent of the distance separating the partitions, especially for depths which are small com- pared to the surface. From this point of view, therefore, the depth of the space may be reduced indefinitely. It is only necessary to make the surfaces, of a material having the smallest possible coefficient of radiation. Moreover, as concerns the conduction of the air itself, the researches. of Nüsselt lead to the conclusion that the coefficient of conduction (con- ductivity and convection together) increases with the depth. For instance it would be from '07 for spaces of from 4 to 14 centimetres, '03 for spaces of about 1.5 centimetres, '02 for very small spaces. The tests which we have carried out at the Conservatoire des Arts. et Métiers on flooring made of hollow bricks with air spaces were in ac- cordance with these results, at least in a general way. But we have noted that, in the case of an air space of considerable depth (12 centimetres),. the fall in temperature across the gaseous medium is almost entirely con- 217 ." centrated in the part immediately in contact with the solid surfaces under a layer less than 8 millimetres in depth. Jace &cºde --- 0° *— — — — *-* - - G--- A. A ŻTTT * ––– * *—--- S-31.7 — 2%z-- * * - - * * - - }* =s* - * *m- - - - wºm" - &ce ckºff. - 22,5 ZZZZ 2. IE zž *::: * * --s • * * ~ * zzºzzzzzºzzzzzzzzzzz 2. a’A %22zzºzºz. * *- - - - - - - * * *- :- chaº • - 21 &ce J.coide zzzzzzzzzzzzzzzzzz, T ~ ſt 2%z}zž TT f ZŽZZZZZZZ ~ ZZZZZZ Z%ZZZZZZZ The temperature diagram of the two hollow floors which were tested (see figs, 2 and 4) shows the relative importance of these drops in temperature. 218 From this it may be concluded that the greater part of the insulating capacity of these air spaces is concentrated within a space of from 15 to 20 millimetres. This is confirmed in the diagram (fig. 2) by the fact that the drops in temperature in the spaces A and C., 25 millimetres deep, are practically the same as those in the space B, 110 millimetres deep. Finally, it may be assumed in all cases, that it would be practically useless to have air spaces more than 20 to 25 millimetres deep. Beyond this the insulating capacity increases very slowly. Moreover. it seems from the results obtained by Nüsselt as well as by ourselves that it would be possible to still further decrease this thickness without much loss of efficiency. - If we now calculate from the temperatures in diagram 2, and basing the coefficients of each of the 3 air spaces upon the coefficient of con- . ductivity found for the whole flooring (0.59), we easily find these to be 0.246 for the space A–C O'92 X) X » B–C O'34 » 2 » C–C From these figures, assuming that the coefficient of radiation for the various materials under consideration is the same, which is practically true, we can deduce : 1. That in the case of partitions having a conductivity above 0.9 (stone, limestone, rubble, and concrete), it is advantageous from the point of view of insulation to replace Some of the solid material by air Space whose depth may be as much as 10 centimetres each, or even more, if the coefficient of conductivity is above 0.9. 2. That for material whose coefficient of conductivity is between 0.3 and 0.9 (brick, terra cotta, and plaster) air spaces at least 2.5 centimetres deep may be advantageously substituted for an equivalent thickness of material. 3. That for material whose conductivity is less than 0.3, and espe- cially for proper insulating materials (cork, sawdust, peat etc.) the substi- tution of air spaces 25 millimetres deep for equal thickness of insulating material would diminish the insulating effect. It is possible, however, that, with much smaller air spaces, it may be advantageous to effect this Sub- stitution even in the case of insulating materials such as cork, but as yet there are no experimental data fixing this point. In any case we may add in a general way that for an equal depth of imprisoned air the efficiency is in proportion to the number of air spaces. Note that these results only apply to temperatures which are met with in refrigeration installations, that is to say, below 40° C. Nüsselt has shown that at high temperatures the effectiveness of the air decreases very rapidly, because of a considerable increase in radiation and convection. 219 ,Zementholz” (Converted wood) as Insulating Material. By Wilhelm Figdor, Vienna. Experience in the use of insulating materials has shown us what the refrigeration industry requires to-day in good and applicable insulating material. - - I would like to briefly state these requirements: Lowest possible heat transmission; Greatest resistance to heat, cold and fire; Resistance to every kind of decomposition, fouling, etc.; Greatest possible strength and durability; Easy manipulation; Manifold applicability; Lowest possible cost. It is not necessary that we investigate all insulating materials now in use from the above points of view, but I am nevertheless in position to submit for consideration a new insulating material, which fairly well satisfies all the conditions above mentioned. This material, the manufacture of which was commenced about a year ago, is called 27.ementholzº (2 con- verted woods) by its inventor; this name explains what the ingredients of which the material is made up are. The name swood cement< would be more correct technically, but the material is already introduced under the former name and we will keep to it. »Zementholzº is made of sawdust and Portland cement. Its manufac- ture is rather difficult as the binding process is dependent upon atmospheric conditions. The impregnating of the sawdust and the mixing of the two Substances of such different weights are not simple operaiions. The properties of >2ementholzº may be to some extent determined from the samples handed round. It is fairly light, the S. W. is 90–95; it admits of being sawn, cut, bored and nailed as wood does and therefore it is extremely handy of application. It may further be seen from the offi- 220 cial certificates of the technological museum of trades and industries that »Zementholzº shows considerable solidity and is both frost resisting and fire proof. Water absorption diminishes the solidity, but where dampness occurs. we make use of a bituminous coating which completely prevents any mois- ture from entering, while it in no way diminishes the insulating value. Insulation tests have shown that the coefficient of heat transmission is about the same as that of the best cork board. Trials were carried out simul- taneously with > Zementholzº and reform cork board. It is of interest that after one side of a slab 4 cm thick had been exposed to fire for one hour, the other side was only just warm. Even after three hours it was not so hot that one could not bear the hand on it. From this alone the enormous insulating effect is evident. I must also mention that at the carpenter's fire tests on 28* September 1909, Zement- holz's proved superior to all similar materials in its fire proof qualities. Now I come to a point which was mentioned yesterday by others as being the most important requirement of an insulating material; namely, that insulating material should also posess the quality of being a good building material. 27ementholz, fully satisfies this fundamental requirement. It is at present much used as building material, especially where heat and deadening qualities are needed. As regards the special case before us to-day it may be of interest to mention that at the new Presburg Ice Works all insulation work was done with >Zementholzº, and that it has proved excellent. At present the 57ementholz & Works at Neumarkt-Kallham make slabs of 30 × 70 cm in three thicknesses, 2, 4, and 6 cm. For insulating pipes, molded sections are being made of > Zementholz, by way of experi- ment, and the above Works will probably soon be in a position to deliver pieces in any desired shape. Plants to arrange for supplying material for applying Zementholz mastic to surfaces direct are not yet matured, but, to the best of my knowledge, are being carried on energetically and with every prospect of success. Y. 221 Cork as an Insulator of Heat. By Max Grünzweig, Certificated Engineer. The conduction of heat of all porous substances of decreasing density. tends towards the limit :02, the coefficient of still airl). The more the homogeneity of the solid substance is perforated with the minutest pores, the more nearly it approaches this limit so that the fraction of difference from it of the total conduction of heat becomes insignificant. Its own con- duction can therefore be neglected, and only the transmission of heat in still air is measured. In what manner a substance ordinarily considered to be a good conductor thus changes by stages to the contrary is shown by a series of observations made by Desvignes”) on the various fixed modifi-- cations of water. -- Density Conduction * @ e º 'º a tº e e '99 2: 10 Snow . . . . . * * * '90 1.97 > * * * e is tº s '50 ‘61 X tº tº sº º e º 'º º '10 - :02 identical with still air The relations between density and conduction ace, however, not of so simple a nature, that of two insulators the lighter is also always the better”). The same material may, indeed, at the same density, give entirely different values, and in spite of decreasing density yet become a better insulator. 1) Winkelmann, Handbuch der Physik 1906, Vol. III, 535. *) A. Desvignes, De la conductibilité des matériaux isolants I. International Cold Con gress, Paris, 1908. *) Compare Nüsselt, Dissertations of the technical universities Munich, Berlin 1908. 222 Material Density Conduction at 0°C. Cotton . . . . sº e < * * * * '81 ‘O47 Silk . . . . . . . . . . * * * * * 1.01 ‘O38 Wool . . . . . . . . . . . . . . . 1.36 •033 The following consideration enables us to get at the connection bet- ween density and conduction: Let a = density of insulator = solid + pore volume. 6 = density of solid (porousness) /* = conduction of solid, fo = a quantity representing the function of the total surface of the pores, * then the conduction of the insulating material will be directly proportional to the expression: AE 6 º . o is variable, when a is constant, that is at equal volumetrical weight a material can either contain few and coarse or many fine pores. In the first case increased conduction of heat results through convection, and so the insulating effect will be slighter. Wool, in spite of having the greatest density exceeds silk and cotton, because its greatly felted and very fine fibres are able to form a greater number of small pores than they. To the above formular we owe a second very important result. If a constant ois taken for each a, as for example is given by wool through the length and thickness of the threads, then as o is also a function of a, and in such a manner that if a continually decreases then 7ſo gives a mini- O mum quotient. Of all space densities of an insulator this is a particularly excellent state and one at which the very best insulation result is attained. If the choice of our insulating material be decided by its conduction of heat alone, then every solid, at its most favourable space density will be equally suitable. The space density (compactness?) may be varied by granu- lating to different degrees of fineness. In actual practice, however, the number of available materials becomes very small. If we designate the non-communicating hollow spaces enclosed in the untriturated substance as * closed volume of pores&, and if we desi- gnate those spaces which communicate with each other and the air spaces between granules as x free volume of poresº, then stuffs with the greatest possible closed volumes are practically of incomparably greater value. When the closed volumes of pores are equal, preference will be given to the 223 - - - material with the smallest a, the greatest 6 and o, and the lowest A. Accor- ding to our formula it has the lowest conduction of heat, and in order to make use of the criteria introduced by Kritzinger") for the practical value of an insulator, it will also have the least filling density and the smallest insulating weight. In granulated state, with equal insulation effect, it will give the coarsest granule and the least free volume. Apart from the various dis- advantages resulting, for the insulation method, from a very fine grain with loose filling, the great importance of the last factor is to be found in the Fig. 1. Natural cork. Section through the cells parallel to the trunk. (Leitz Microscope: Ocular 1, Achromat 5, length of camera. 203 mm). behaviour of the insulator towards dampness. It is just in the insulation of cooled rooms that there is the danger of condensation of moisture, if this in vapour form can unhindered get into the free volume of pores from the warm outside to the zones cooled to below zero. The finer the granule, however, the greater will be the capillary power it develops to absorb moisture and transfer it to the surrounding neighbourhood. When it is re- membered that the best insulator becomes valueless as soon as it becomes *) Kritzinger, the practical importance of conduction of heat and the filling density of insulating material, International Cold Congress, Paris 1908. Reports. Vol. 2. p. 519. 224 wet, it is quite unnecessary to call to notice the destructive effects of water, particulary upon vegetable and animal insulating materials, in order to point out the enormous disadvantage of a free volume of pores. With all loose filling material, however, such as lamellar coal turf, broken up slag pumice, , artificial wool and such like, this amounts to from 30 to 50 per cent, on an average, of the total volume. . . . . . . g Free C on du c ti o n Density Volumes , 09 1000 Cork . . . . . . . . . . '175 09/, O'66 w - Desvignes Cork granules Nr. 1 (Dia- meter about 1 mm) . . . ‘161 |Ica. 30% ‘O31 '048 Cork granules No. 3 (Dia- meter about 3 mm) . . . ‘O85 ca. 50% ‘O40 ‘O57 - 0-06 - 0-05 - 0:04 3 § H 0.03 "& *—l er, º: - 0:02 Ž 3. p-4 8 ... I 3. < 0.01. Z. *— A g I sº - Al- =sel *- - i. —w o:04 0.06 0.08 0:1 0-12 0-14 0-16 018 T)ichte - The ideal of an insulator must therefore unite a smallest possible con- ductive power, with the smallest density and complete absence of free volume of pores, with absolute water proof qualities, and good constructive properties. Fortunately Nature has provided such a raw material for us in sufficient quantities, which, unique in its nature, comprises almost all of the advantages just mentioned to a high degree. I mean the bark of the cork 225 oak which thrives on the coast lands of the Mediterranean. Under the microscope it appears as an exceedingly delicate walled network of the smallest polygon shaped air cells, whose structure forces comparison with the honey comb. Every separate cork cell is hermetrically closed on all sides, so that here millions of the smallest cells help to build up an in- sulator on the principle of "still airs, such as cannot be more perfectly imagined, from a theoretical stand-point. If, therefore, the microscopical examination leads us to hope for a suitable still air conduction in cork, then Desvignes’ experiment brings dis- appointment. The quantity 0663 we presume is one or two hundredths too high (about 04 to 05), but even this gives a very close approach to -02. In the space density 175 (Desvignes) the influence of the solid material is probably still noticeable. As Ó and o in our formula with cork are natural sizes, we can only reduce the conduction by decreasing a. When we granulate the compact cork to grain No. 1 of about 1 millimetre section the conduction, according to Nüsselt, actually does sink to 031. With further reduction of density we experience an example of the case mentioned at the beginning for the conduction passing through a minimum, since at density '85 a further rise to '04 results. We had explained this law by the dependence of the size of o on a. True, it became evident that if no. 1 granule replaced compact cork, a and o would necessarily decrease. As & e (Z * the decrease of a predominates, the quotient To also becomes smaller. In passing from no. 1 to no. 3 granule however, the reverse occurred, namely, that the decrease of a could no longer keep pace with o. This results in an increase of quotient and thus of conduction also. Practically no. 3 granule lies with coarser and also fewer x frees air pores than does no. 1 granule, with a consequently noticeable influence of the convection. In what form do we meet with cork as an insulator in cooling plants in practice? Natural cork plates prepared by cooking and pressing are inadmissible for economical reasons, apart from the fact that they are with difficulty ap- plied, owing to their uneven thickness and structure. One is driven to make use of the waste from the plates made for trade, and also of the fairly considerable quantities of waste from the manu- facture of cork stoppers. This has in the first place to be reduced to a certain size of grain. The idea of using this cork waste as loose filling would, according to above trials, be so much the better, seeing that cork granules ensure a greater effect than a natural plate of pure cork. The gain will, however, become questionable through the disadvantageous effect of the free volume of pores in cork granules. Unfortunately cork proves especially hygroscopical and with longer damp action fouls. An isolation with loose filled cork grains is therefore only very seldom used in actual practice. 15 226 On the other hand processes have resulted from the development of the cold industry for preparing a constructive building and insulating material out of cork grains, and this is in great favour and employs numerous special factories. This product, variously named and difficult of uniform classification, I will divide into two groups in reference to the foregoing observations: I. such as has only closed volumes of pores, II. that with free and closed volumes. According to their best known representatives group I. may be desi- guated Press cork, and group II. Cork Stone. # The manufacture of cork-stone and its relations consists in the pre- paration of cork waste with a watery, mineral or organic binder to a mash from which stone, plates, etc. are formed exactly as in brick making, which are ready for use after a drying process at moderate heat. Or it is stirred up with liquid pitch and after filling into forms allowed to cool (so-called pitch cork stone). In consequence of this manner of preparation a porous structure is common to all such fabrications, easily recognisable by the fact that water placed on the upper surface of a cork Stone soaks in and flows out at the bottom. The degree of porousness may be judged by the rapidity of this action; on an average it may be 20 to 30 per cent., according as fine or coarse grains are used. For protection against penetration of moisture the process has been developped of impregnating the already formed product by a final extra treatment in fluid pitch under pressure and vacuum (Reform Cork stone), Pitch cork stones are water proof in consequence of the manner of their preparation, but they dissolve with warmth and are not of stable volume, The specific gravity of a prime quality cork stone may vary between 0:2 and 35, of which 1 to 15 represents the cork and the balance the binder. The conduction of heat is '05 to '96 under favourable circumstances, according to the results shown by various trials. The binder, which takes up but a small proportion of space, is a relatively good conductor in com- parison to cork (no. 1 or no. 3 granule should be used), and consequently raises the conduction there of about 30 to 40 per cent. more Still above '02, With the same quantity of binder and specific gravity a coarse pored cork stone promises a lesser effect than a fine pored one. Press cork owes its name to the pressing necessary to its production, in which the first steamed cork grains, mixed with little or no organic binding material, are pressed together to about */s or /, of their original volume. After removal of the moisture, whereby the heating of the forms may be driven to the point of sweating out the cork gum, the pressed mass keeps its form and shows a dense structure corresponding to the pressing, In consequence of the unavoidable partial crushing of the cork cells (see 227 microphoto.) its density of 25 to 3 exceeds that of the natural cork plate, which it otherwise closely resembles in structure. A higher value of its conduction may therefore be expected, as compared with natural cork, and it will probably be about the same as that of a good cork stone. A principal advantage of the latter is indisputably the absence of free volume of pores, in opposition to which, however, stands the vastly greater require- ment of cork, in the proportion about 3: 1. While only cork stone has been introduced into the cold industry in the Old World, America is almost entirely dominated by a press cork of Fig. 3. Press cork. excellent quality and great moisture resistance, which is known in trade as *Nonpareils. The superiority of cork as an insulator over its competitors is there- fore less expressed in a specially low conduction of the technical cork products regarding which they are even surpassed by silk and wool for example, but much rather in their handiness and easy adaptation to the particular construction. They also offer a more effective protection against damp. 15* - - 228 A further development of insulation materials, specially directed to a decrease of conduction, appeared to be so improbable of late years, with the high perfection of available types, that Mr. J. Stone"), a prominent re- presentative of the American cork stone industry, at the I. international Cold Congress *) made special mention of this point. He gave as reason that all natural products possible as insulators had been already examined, so that a new and better insulator could hardly be expected. An ever recurring experience in the history of technics shows that just at such periods of apparently completed development a keen compe- Fig. 4. Upper half natural cork, lower half Expansit. Section through the cells parallel to the stem. (Leitz Microscope: Ocular I, Achromat 5, length of camera 203 mm.) tition produced perhaps by continual rise in the price of raw materials or by other economical factors directs attention necessarily to making the utmost use and improvement of raw materials, and as a result raises height- ened possibilities of development, previously passed by without attention. Such reasons, a systematic study of the possibilities of improvement of raw cork, led to the discovery of its most valuable, yet hitherto overlooked insulating property, whose practical application is about to introduce a thorough revolution of the hitherto customary methods of manufacture and insulation, 1) J. H. Stone, Insulation, American theory, Result of Experiments and Application. *) Reports, Vol. II, p. 556. 229. The name º Expansit has been chosen for the improved and some- what ennobled raw cork, to indicate, that it has enlarged, expanded its vo- lume, and that, indeed, to the double volume. The astonishing phenomenon takes place when the cork is heated to a temperature between 300 and 400° C), all air acids being most carefully excluded, and cooled again in the same manner. A comparison of the microphotographs of raw cork and Expansit confirms distinctly the growth of the cork cells which in raw cork are still partly slack and folded, but in Expansit stiffened out to the utmost. - - - - - - - - - - - - - - - - - - - - Fig. 5. Upper half natural cork, lower half Expansit. Secton through the cells cut perpendicularly to the stem. (Leitz Microscope: Ocular I, Achromat 5, length of camera 203 mm.) The deep browning of Expansit shows that, besides the physical process of cell expansion, a chemical process has also taken place. While about 30 per cent of its weight has distilled off in the form of easily separating parts the hygroscopical and fouling properties of raw cork have been entirely lost, and it is as little wetted by water as is any greased object. Expansit there- fore, in contrast to raw cork, is also indefinitely stable in a damp condition. Expansit stone formed without binder from the expansit granules is similar, in its homogeneous air and water-tight properties, to the American *) Compare D. R. P. ang. G. 24016, IV/38 h. 230 press cork, from which, however, it differs by being */s lighter and having better insulating capacity. It is identical with pure Expansit, as both show the same density. On account of expansion and loss of destillates this amounts to one third that of raw cork. As the total surface of the cells, o, has only decreased to a lesser extent than the density, a, we may expect a noticeable reduction of the conduction. Trials at the technical university at Munich for Expansit stone, pure Expansit substance and granules 1 and 3, in the same kind of grain as the cork formerly, actually gave values about 30 per cent. lower. Here, too, the conduction gives a minimum, inasmuch as with granule No. 1, with about 40 per cent, free volume, it even becomes identical with still air, thus touching the borders of theoretical possibility. —T-T—T-T— Conduction º Volume & Difference Density - of pores 00 C. 100° C. | 0°-100° C. f.e. Expansit Stone . . . ‘O8 "O352 ‘O420 •0068 09/o Granule No. 1 . . . ‘O47 ‘O243 '0330 :0083 40°/, Granule No. 3 . . . '044 ‘O363 ‘O460 '0097 || 45°/, Wool . . . . . . . "136 ‘O33 “O50 •017 It is also very interesting to watch the influence of the free volume of pores on the behaviour of the conduction of heat at increasing tempe- ratures. The increase for Expansit stone with only closed volumes is the least, being '0068, that of No. 3, with the maximum of &free.< air, is the highest, being 0097. - Insulating * Filling density | "...º." qm, St. Expansit granule No. 1 . . . . . *0243 ‘O47 5-6 Expansit stone . . . . . . . . . ossº '080 14 Cork granule No. 1 . . . . . . . ‘O31 *160 25 Peat mould . . . . . . . . * * * ‘O40 '161 32 Lamella coal . . . . . . . . . . '05 “215 52 Cork Stone, about . . . . . . . . ‘O5 about 250 62 Press cork, about . . . . . . . . '05 about 250 . 62 23 f A glance at the above table shows that Expansit takes the first place not only as regards conduction but also in the other technical and price affecting values of insulators with definite factors, namely specific gravity and filling density, insulating weight and water resistance. The insulating weight necessary for attaining a certain insulating effect, e. g. the requisite weight of insulating material for 2 calories per square metre of surface, hour and 19 C. temperature difference is the standard for price calculation. As apart from the slight conduction, a 100 per cent. cork substance is created so to say, by magic, out of nothing, through the expansion of the cork cells, the amount of cork used for cork stone is nearly double that required for Expansit stone, and for press cork about three to four times greater for equal isolating effect. The importance of this question may be so much the more readily estimated, if we remember that with the continually increasing requirements of cork for the cold and linoleum industries a continual rising tendency is to be expected in the price of the raw cork. The fortunate property of Expansit which offers great indifference to moisture, allows of unhesitatingly using it as loose filling. It can be employed in complications, the attachment of pieces of difficult construction such as very irregular shaped rooms in ships, or when, as for scientific experiments,”) the very greatest insulating effect is necessary. In such cases Expansit No. 1 can be used with success. The extremely slight filling density and the slight hygroscopicity of Expansit ensure for it here, too, an advantage over all other insulators. According to the account of trials of the technical experimental institute of the Technical University at Karlsruhe, the quantity of water absorbed by Expansit No. 3, Cork granules No. 3, and Lamella coal while lying 96 hours under water was as follows: : Densi Absorbtion of water ensity º in Volume-9/o Expansit granules No. 3 . . . . . . . . . '034 3-6 Cork granules . . . . . . . . . . . . . ‘165 15-3 Lamella coal . . . . . . . . . . . . . . . • 198 21.2 - *) Compare Zeitschrift Deutscher Ingenieure" 1910, p. 1319. Dr. Ingenieur Gröber used Expansit granules for the insulation of his experimenting apparatus for heat conduc- tivity of building and insulating materials. 232 Here it must be added, 5that Expansit granules No. 3 dried very quickly and within 24 hours had already attained to their original weight, while > cork granules No. 3 exhibited a considerable amount of moisture content after three days time.<. According to Kritzinger the insulating value changes in proportion to the square of the hygroscopical degree. One main advan- tage of the slight filling density of Expansit granules is the slight self- pressing, which entirely obviates a sinking of the material, making the trou- blesome after-filling unnecessary and avoiding a continual deterioration in the insulating effect by increased density of the lower layers. Expansit stone is like cork stone in its excellent property of combi- ning directly with every mortar; it shows itself in opposition, however, by an insulating effect about 60 per cent. greater, º/, less weight, and absolute air and water-tightness. (A trial piece kept under water shows even after a long period but little addition in weight). It promises, therefore, to become a valuable pioneer for the further extension of the cold industry, especially in the sphere of non-stationary cold plants, for ships and cold transports, indeed, everywhere where the economy of dead space and weight is deci- sive for the choice of an insulator. 233 The Cellular Calorifuge. (System E. Brousse.) By M. Juppomt, Engineer of Arts and Manufactures at Toulouse (France). This Calorifuge is formed essentially of two kinds of partitions alter- nately superimposed and separated by a layer of air. One of these partitions is made of metal which is polished and shining on both sides (the thin metal plate is of iron, nickelled, tinned or silvered over, etc.). The other is composed of an insulating substance (felt, cloth, cork, card-board, etc.) The properties of these partitions cooperate in retarding the con- duction of heat. $ In short, the burnished walls which receive the calorific flow, reflect it back to its source, and consequently allow the transmission of but a slight part of the flow which they receive ; and, as the emissive power is nearly proportional to the absorbing power, the result is that the second bright face of a plate tends to emit only a feeble portion of the heat which reaches it. The transmission of the flow which issues from a burnished metallic partition is in its turn retarded by the air and the insulating partition which it has to cross before arriving at the next polished partition, which again will reflect to its source the weakened flow transmitted to it. The succession of obstacles identical to that which has just been described, allows an insulating wall to be continued, and this is as much more efficacions as its elements are more numerous, and so much the more convenient as (by its peculiar construction) this insulating agent is light, of slight thickness, as it presents a great Solidity, can easily receive all shapes and as it is not hygrometric. Recently applied to the Cookers × Calida Semperº of the system of the captain de la Taille, used in the grand manoeuvres of 1910, this insu- lator has furnished the following results: The water or the foodstuffs at 100° C placed in a cooking pot provided with a calorifugal envelope of the system Brousse were at a temperature of 75° C at the end of 24 hours, and at a temperature of 61° C after 48 hours. 234 Insulating Materials. 7th and 8th Questions. By M. Masse, Engineer of the Agglomerated Cork Company, Denniel & Cie., Paris. . At the time of the meeting of the first International Congress of Re- frigeration, several resolutions were proposed and passed concerning insula- ting materials for the purpose of investigating their conductivity as a func- tion of temperature, thickness, degree of moisture, and of other causes which influence this conductivity. - - Moreover, the experimenters were invited to carry out researches on the materials generally employed in refrigerating installations, and to carry out these experiments, not upon assumed thicknesses of some millimetres, but upon thicknesses of from 10 to 20 centimetres, as commonly used in this industry. 4. * M. Biguard, in his report, gives a description of the apparatus which he has devised, and which satisfies the various requirements. - In this apparatus, the thicknesses which are submitted to conductivity tests are those which are commonly met with in industrial installations; and the arrangement adopted allows of measuring their conductivity as a func- tion of various temperatures, chosen in each case as the limits of the appli- cations for which they are intended. It may be concluded from this, that for each variety of insulating material, it is useful to make out a scale of conductivities, for variations in temperatures, corresponding to the different cases met with in the study of refrigerating plants. - - For instance, such an insulating material would have a mean coefficient of conductivity between – 10° C. and + 100 C.; then between 0° C. and + 20° C. etc. - ~ * A table of the principal insulating materials commonly employed would, according to the various coefficients corresponding to different temperatures, allow of determining for a given installation, the choice of an insulator, its thickness, its effect, and its cost. . Another table, drawn up by ascertaining the variation in the coefficient, under the influence of moisture, would show when certain insulating materials 235 are desirable, and which are to be avoided, according to the requirements of the plant and its more or less appreciable exposure to moisture, and lastly according to whether the builder intends it to be of a temporary or durable character. * In the use of all composite insulating materials, the question of the binding material is very important from the points of view of insulation, and resistance to alteration, and hence the permanence of the insulating qualities. - In order to reduce the losses of cold, the natural thing to do is to reduce the number and size of the joints, and hence to make use of large pieces of material. - To prevent these losses it is usual to divide the thickness of the insu- lating covering provided into two parts, in such a way that by breaking joints their depth is reduced and the joints are not made continuous through the whole covering. - - This precaution is not so necessary to observe when the joints are made with the same adhesive as serves to hold the insulator together. When, for instance, large sheets of cork, 100 metre by 0.50 metres in size, impregnated with resin throughout areused if the joints are filled with resin paste each partition is obtained in the form of a continuous panel, as if the insulator had been poured over the partition itself. Dividing the total thick- ness of the covering into two parts is not so advantageous. By adopting the principal of insulating the interior of cold rooms, a covering may be obtained without interruption of continuity on the floor, the ceiling and the walls, and a sort of continous protecting shell is thus obtained. * *- * One is sometimes tempted to make use of an exterior insulating cover- ing, because it possesses the advantage of protecting the walls from the heat of the outside atmosphere, and allowing the use of these walls for storing the cold when the source of refrigeration is stopped. But it should be noted that an interior covering is generally more prac- ticable, especially in a building which is already finished when the refrige- rating apparatus is put in, moreover it is more easily made continuous. Besides, it is always possible, as an interior covering to provide an accumulation or store of cold by means of hollow space of a convenient thickness and made of ordinary or hollow bricks; or by means of flat brine tanks, of walls of brine so to speak, which may be attached to the walls of the rooms. For the insulation of refrigerated spaces the following insulators are generally used: Confined motionless dry air, sawdust, shavings of soft wood, pine wood with or without a coating of plaster, bran, animal hair felt, insulating 236 paper, peat, pumice stone, hollow bricks, mineral wool (or slag wool) infusurial earth, asbestos, charcoal, granulated cork, cork in slabs, agglomerated Cork, with various adhesives, etc. - Among these insulators, whose coefficients of conductivity vary consi- derably, some are hydroscopic, and become, after a time, good conductors of heat, others lend themselves to the development of parasites, others again are very inflammable; others of organic origin gradually decompose, ferment and disintegrate under the influence of moisture, become covered with mould, and give forth bad odours. ; *- Their resistance and durability are therefore variable, and these two qualities must be taken into account according to the character of the in- stallations to be set up, according to whether it is necessary to have con- structions which are to be more or less temporary for the sake of economy, and so that they may be quickly brought into use; or whether it is neces- sary to have constructions of indefinite durability, so to speak, made of materials selected so as to insure the minimum cost for maintenance and repairs. Certain methods of insulating by multiple partitions have the incon- venience of requiring great thickness and hence of reducing the avail- able space. - Also dividing up insulators is sometimes resorted to, by the interposi- tion of several air spaces, in order to increase their insulating power. Though it is sometimes possible to make use of dry motionless air, well held in position, it should, nevertheless be noted that these conditions are generally difficult to realize; it follows, that if on the contrary moving and moist air are obtained, the result obtained would be quite the opposite from the result aimed at. * - .* M. Biguard in his report, using the experiments made at the labora- tory of the Institute of Arts and Crafts, gives some useful information on this matter. f Summing up, it is generally recognised that a good insulator must be solid and, at the same time, porous to a certain extent, the cells of air being exceedingly small and numerous, and shut up in the mass, which greatly increases the insulating power of the material. This insulating power, then, decreases with the density of the insulator., It may be of interest to estimate, not only the cost per square metre of putting up an insulating covering on the wall of a cold room, but, at the same time to estimate the price per unit of the negative calories, or frigories, kept in the cold room under consideration because of to the use of the insulator selected. If the difference between the number of calories transmitted through an uninsulated wall and through the same wall provided with an insulating covering is m, the following value is obtained per square metre per degree difference per hour: 237 m = } 1 – E - ETE a 5+a; If E = the thickness of a masonry and stone wall – 0.5 metres C = The coef. of conductivity of the said wall = 1.30 E’ = The thickness of a slab of agglomerated cork = 0.05 metres C = The corresponding coefficient of conductivity = 0.05 we obtain II] = 1878 calories. Assuming the average price of agglomerated cork of the best quality to be 100 francs per cubic metre, the price per square metre of the insu- lating covering, which we will call P is 5.00 francs. Also, if (t—e) = 12° C is taken as the mean temperature difference, and if the time is taken for 360, 24 hour days a year during the period of 10 years for which the plant under consideration would last, the follow- ing value of the cost p, for the preservation of one frigory would be obtained: P PT m × 24 × 12 × 360 × 10 and for 1,000 frigories: 1000 × P + 1000 × 5 m × 24 × 360 × 10 × 12 1.878 × 24 × 12 × 360 × 10 5 == 0.0025 francs. = 1.878 × 1036.8 Lastly, if we notice that the cost of production of 1000 positive calories is 0.005 francs, reckoning from the fact that 5,000 calories are produced by the burning of 1 kilogramme of coal at 25 francs per ton, and that the cost of production of 1000 frigories is 10 times higher or 0.05 francs, it can be seen how advantageous it is to preserve the frigories in a cold room by means of an insulating covering, that is to say at a relatively small cost. - If we consider the thicknesses of insulating material usually employed in refrigerating plants, we can draw up the following table, in which : E represents the thickness of the insulator (agglomerated cork); P represents the price per square metre of this insulator; m represents the number of negative calories per square metre preserved in the cold room, because of to the insulator used. p represents the cost of preservation of 1,000 calories per square metre, for an average temperature difference of 12° C, for 10 years, each consisting of 360 days of 24 hours each. \ 238 E P IIl p O'050 5:00 francs 1878 calories 0.0025 francs 0.060 6.00 x 1969 X O'0029 x O-080 - ,800 x 2.096 > O'OO38 s O' 100 10:00 x 2:181 X 0-0046 » O'120 12:00 x 2°241 X 0.0051 > O 150 15:00 x 2:305 X O'0062 > O:200 20:00 x 2.372 X S O'O083 × O'250 25:00 x 2°414 }> O'O100 x O'300 30:00 & 2'444 » 0.0118 × By varying the thickness and the composition of the walls, and hence their transmission by conduction, it may be ascertained whether there is any advantage to be gained, beyond a certain point, by increasing the thickness of the insulating covering. We have not included in the cost P per square metre of insulating material, the cost of putting it in position, which naturally varies, according to the manner of application, the place where the work is carried out, also the amount of work etc. this price for placing in position generally being between 1:50 francs ond 500 francs per square metre. We can make out tables along the same lines for the various insu- lating materials used in the refrigerating industry, by basing our calculations upon the cost of these insulators and upon their coefficients of con- ductivity. We will be satisfied with suggesting that these tables be drawn up, before undertaking this considerable amount of work. We decided to confine ourselves simply to the cases where agglome- rated cork is used, the use of which is becoming more and more general in all installations where efficiency and durability are desired. Knowing the cost of installing refrigerating machinery and that of continuous production of cold, the exact cost per negative calory or frigory can be determined. Summing up ; by applying the preceding calculations to the total sur- face of insulated partitions, to the average difference in temperature between the outside atmosphere and that of the cold room and to the number of hours under consideration, the expense for the insulator employed may be ascertained, as well as the quantity and value of the frigories preserved in the cold room by the insulator selected. 239 The Theoretic and Actual Insulating Value of Hollow Spaces. By Friedrich Rudolf Metz, Technical Director, Vienna. Although a positive position is taken in the literature against the use of hollow layers, and although such authorities as Prof. Nussbaum condemn the introduction of air spaces in dwelling houses, yet they are still some- times provided in new cold stores, though almost invariably in combination with a heat protection means such as cork, etc. It may therefore be of interest to trace the causes of the failure of this out-of-date method of insulation. An exact examination of the effect of air layers is also of value on account of the fact that in the latest hollow concrete constructions air spaces are made use of for purely constructive reasons. The heat transmission through a wall is, as is well known, only determined by the time, the surface, the temperature difference and the coefficient of transmission of heat of the wall (for the particular moisture content). With air spaces, on the other hand, the transmission of heat depends not only upon these factors but also upon the quantity of current and radiation. The amount of heat transferred to the air layers by conduction is exceedingly small. That transported by radiation is greater. Far the largest amount, however, can be transported by air currents, if conditions are favorable. As the amount of heat radiated increases in the proportion of 1 : 4 of the temperature it is deducible that the insulating effect of air layers, even with still air, must decrease rapidly with the temperature. - If the air in the hollow spaces is saturated, then under similar condi- tions an equal current will transfer considerably more heat, owing to the greater heat capacity of moist air. If water is actually evaporated on one side of the hollow layer then the great evaporative heat of the water will be bound and set free upon condensation on the opposite surface. It has been proved that this condition may often occur in practice, particularly in refrigerating plants, and that under some conditions water collects on the floor of hollow layers, as a result of the sweating. The reason for this phenomenon is that the water that has penetrated and been transferred by evaporation and condensation to the opposite wall surface cannot return, 240 owing to the direction of the temperature gradient which nearly always proceeds from the outside inwards, drying through capillary effect is rendered impossible by the separating air layer. The same process results when different air layers are arranged consecutively. The air current passes from the warm surfaces to the cold ones through evaporation and conden- sation of the water, whilst a back flow, with the temperature gradient remaining the same, is impossible. This consideration shows that the passage of heat through air layers must vary with the conditions. We have ourselves made experiments with our new apparatus, whose manner of working was explained in the previous paper, to test the insulating value of air layers of increasing dimension. In these tests completely dry air was applied. The heating of the air took place from the bottom upwards. The air layer was horizontally placed. The results showed for a thickness of 55 mm. a transmission of 56 cal corresponding to a W. D. C. of 0.03104 » 11 X X X » 5 X X. X X » 0-04021 » 20 X > X » 4'2 > X » X » O'O8576 x 30 X > X » 4 1 » X X X » 0°12477 2 80 X X X » 4-2 > X X X » O’33664. From these experiments the amount of heat transferred by the current may also be seen. We find, further, that the slightest heat conductivity is possessed by the thinnest space and that it increases rapidly as thicker spaces are taken. We see that the transmission of heat varies very slightly, thus that no result is attained thermo-technically if instead of a thin air space we make use of a thick one. Co m p a r a ti ve tests showed for a completely dry brick wall a coef- ficient of heat transmission of 0-32. The brick had a volumetric weight of 1:4. The same bricks with 5'5"/o moisture gave a coefficient of heat trans- mission of 0-6. An air layer 8 cm. across therefore corresponds in its trans- mission, in the above mentioned arrangement, with dry brick work. To com- plete the picture we mention that an 8 cm. air layer corresponds in this case with the insulating value of 1 cm. C or k – S 1 a b. If we now examine what has been Said by taking some examples from practice, we find that the most favorable condition for an air space insulation is that it be horizontally placed and with the heat passing through it from the top downwards. This condition is presented, for instance, by a flat roof with air layers over a cold room. The effect even in this arrangement is made worse by the fact that structural parts transfer heat and cause current in the apparently still air layer. The arrangement exhibits the most favorable case for the insulating value of an air space. For a factory roof, however, this best imaginable arrangement becomes the worst imaginable during winter, when the temperature gradient is reversed, for the heating of the air results from below, and must give rise to great air current. . 241 It is true that it is found that the effect of hollow spaces in vertical walls is independent of the direction of the passage of heat. All other factors however remain the same. Above all the intensity of the air current will attain to great importance and even the transmission of heat through water may attain its maximum in this arrangement. As an example we will consider an outer wall provided with hollow spaces in which throughout the year there exists a low temperature and a constant direction of the temperature gradient from outside inwards. Quite apart from the moisture of the building the outer masonry will be wetted by rains. In the air layer the air will rise on the warm side to fall again on the cold side. This current generally causes saturation of the inside masonry, next the cold room, through evaporation and condensation. If work is uninterruptedly carried on in the cold room, it is quite impossible for the water of itself to return, for when the outer masonry is colder than the inner masonry, that is at the only time when the re-transfer of the water could take place, the temperature of the whole wall must be zero or below. If, now, as often occurs in practice, such a structure be coated on the inner side with cork-slabs the same process must take place in spite of the in- sulator. The transmission of heat, as such, will be reduced, it is true, but the saturation of the cold-room side of the wall may yet take place though it be to but a small extent. If however, the insulation is affixed to the outer side of the wall and a complete exclusion of water is simultaneously cared for then the above mentioned saturation of the masonry can in no case occur. Naturally it is self-evident that if such insulation is applied to a new building the whole of the moisture contained in the masonry can only escape into the cold room and that, therefore, such an insulation apparently has a worse effect, at first, than the application of the insulator to the in- side of the cold room itself. When the masonry, in the course of time, is completely dried by the refrigerating machine, the injurious influence of the hollow spaces is limited to their low power of heat insulation, and then the dry masonry takes effect with a coefficient of heat transmission of 03 as compared with 0:6 for the wet state. Through this method of insu- lation one attains, not only the reduction through the cork, through the drying of the masonry, but also an effect as though the thickness of the walls, as regards the transmission of heat, were exactly doubled. An insulating effect, even in this case, cannot be claimed for the air layer, and only purely constructive reasons can justify their adoption. Still another advantage, however, is gained by affixing the insulating material to the outer side of the wall, namely, the circumstance that the whole of the masonry behind the cork insulation, to the value of its heat capacity, (specific heat volume) takes effect as a cold storer during the uninterrupted working of the refrigerating machines. All processes that take place in homogeneous solids, as regards the transmission of heat, are shown by the well known formula: 16 242 1. Quantity of heat W = K X; where W stands for the transmission of heat per unit of time and surface, K for the coefficient of heat trans- mission, t the temperature gradient and d the thickness. 2. If W = 1, the formula becomes # = 4, whence, - U. d 3. t = --. K ~ If we take # = Cot o', then the proportion K : W = 1 shows us the size of the coefficient of heat conductivity. As, however, the value of Cot o' is also +, we have in the similar triangle the proportion == H. ln the graphicon the proportion † is constant in the individual layers, therefore º + is also constant, and therefore the quantity of heat transmitted is in a fixed proportion to the temperature gradient. The quantity W may there- fore be marked off from the graphicon with the distances of t. It is almost superfluous to mention that the heat transmission, W, must be the same in the separate layers. The graphicon further shows us that if K == 0, t becomes oo, i. e. for the ideal insulating material the temperature gradient must be infinity. If K = Co, t = 0. Since K = Cot G., we can describe the angle o as good angle. From formula 3 we obtain the temperature gradient d - * as the quotient T{’ If we now pass from a homogeneous body to a layer of bodies with various coefficients of heat transmission the formula becomes 4. W = T 1 — T 2 d d , d n which here shows us the heat transmission, if we take the resistance to be 0. In this formula T 1 — T 2 means the temperature gradient delta A. If we now solve this equation according to the temperature gradient we get d d : d n D=w (; +++. within the brackets. - We can now graphically easily represent this formula which gives UIS the value of the temperature gradient in the separate layers for a heat transmission 1. * As we see from the formula, however, the proportion between the temperature gradients in the separate layers must remain the same for any heat transmission, and thus we get this graphical construction for any total fall of temperature and also the amount of the fall in temperature in the separate layers. If we represent Coto. = K, Cot 3 = K 1, Cot Y = K2, etc. etc. ) for the transmission of heat = 1 D = the value 243 16% - 244 as in the diagram, we get rectangular triangles in which Cotz is always d º tº fe * == As, however, according to construction Cot o' is also = K, we get the value; for the distance t, # for t 1. Thus in the separate distances t, ti, t, we have actually constructed the above mentioned bracketed values. As, however, the total fall of temperature must equal the sum t + t + tº etc., we get the correct temperature gradient, if we divide the sum of the distances t in our graphicon, as has taken place, into as many parts as corresponds with the periodical temperature gradient. This right side graphicon is constructed in this manner. It exhibits the processes in the transmission of heat through a hollow wall with outside insulation of cork. The masonry is first supposed to be moist, the trans- mission of heat is put a coefficient 0-6. The lines corresponding to the coefficients 03 show what great difference t gives for dry masonry, and thereby the important advantages of the insulating effect. The coefficient for the air layer is taken at 0:6 for damp masonry and 0.3 for dry masonry. If we place the good angle for the transmission of heat in the various mate- rials upon the vertices, we can, as the accompanying figure shows, produce a picture from which the proportion of t to d for various distances can always be picked out. This picture I can extend in the same manner as the principal diagram, so that for t I can also obtain the heat transmission without further difficulty. These statements may make it easier, to understand the processes in combination constructions, and the right hand picture may simplify the manner of calculation. 245 Artpumice and Its Use as An Insulator. By Ingenieur Heinrich Ottmann, Munich. Manufacturers in all countries are continually seeking to obtain from their bye-products other useful materials which may be converted by means of some chemical or mechanical process into articles that may be applied principally for technical purposes. Such articles from bye-products generally have the advantage of being cheaper than the articles that have hitherto served the same end. Users have the advantage therefrom. Particularly in the case of such articles as insulating materials, which many countries have to import, in the case of cork in order to make the insulating article from it, the possibility of producing a useful insulating material from a bye-product of the home industry would be welcomed. After many trials it has been possible in Austria to do this, and we have an insulating material, the Ottmann Artpumice, which satisfies all re- quirements. It consists chiefly of silicon, and compared with cork and peat, both organic insulating materials, is an inorganic material which can neither be destroyed by wet or continuous damp, nor injured by fire, for it will not burn. - - It is manufactured dry at all times of the year and contains no ground moisture as does natural pumice, which being a lava product sometimes necessitates thorough drying before application as an insulator. Application. The good insulating properties of the Ottmann Artpumice are due to the exceedingly porous structure which it attains during manufacture (production). The tightly closed little air cells thus produced afford the essential condition for insulation, which is based upon the air confined within the small and minutest cells. The more such little air cells the better the insulating effect. If we consider the specific weight of Artpumice, from 127 to 250 kg, per cu. m. according to its density, it becomes evident that the number of air cells must be very large, for its specific weight is 4 to 8 times less than water, upon which it floats. Such a result has never before been obtained with an inorganic material, for Ottmann Artpumice is double as light as lava 246 or natural pumice. It is therefore possible to transport Artpumice in cars with high sides so that the greatest saving of space in loading is gained. Fifty cubic metres are transported in one car from the Austrian place of manufacture. Its heat conductivity is 0.95 according to tests in the laboratory for technical physics of the Munich technical university. In this laboratory tests analogous to those made with cork stone have also been carried out in a small experimental cellar of 36 cm wall thickness of Artpumice concrete (consisting of portland cement and Artpumice with no other ingredient) to find its insulating and preservative power when used in building ice cellars. The result of these tests showed that 30 kg. ice, placed in this pumice cellar, did not melt until after 340 hours, as compared with 218 hours for cork stone cellars, the same outside temperature being assumed in both cases. The cheapest and most practical application of Artpumice in the refri- geration industry for insulating breweries, stock, fermenting and racking cellars, - then for insulating cold rooms of slaughter-houses, ice cellars, freezing rooms for meat, game, fish, etc., consists in filling loose Artpumice full in hollow walls, which one formerly believed to have considerable insulating value without filling. Cold room ceilings and floors are most cheaply insulated with Artpumice by pouring it in. If Artpumice be compared with other insulating materials, taking the thickness of the insulator as standard, we find the heat conductivity of cork slabs, for example, to be 0:06, and of Artpumice 0.095, a proportion of about 2:3. In other words a 10 cm. cork slab can be replaced by a 15 cm. filling of Artpumice. As inorganic material Artpumice has the advantage that it is not destroyed by damp setting in later in insulating buildings, and its insulating value is not entirely lost. It does not Swell from the effects of damp either, nor does it choke. As already stated it is also possible with a mixture of portland cement, to make the insulation stand for the building construction and this affords by far the most inexpensive ceiling. The possibility therefore exists of making the roof and ceiling of insulated rooms directly of the insulating material, considerably decreasing the cost of building. According to mixture this Artpumice-insulating- concrete weighs 600–1200 kg. per cubic metre, and its reinforcement is effected in the matrix with hoop iron. As such ceiling is much lighter than an ordinary concrete ceiling and is a many times better insulator, every expert can calculate for himself the further advantages and saving gained by Artpumice ceilings. Remembering the very porous character of the material, its practical use for non-dripping stable roofs, dairy, machine house, and boiler house ceilings is advantageous in so far as all these constructions must, in any case, be provided with an insulation, whereas this is unnecessary in the case of Artpumice, which is itself an insulator. Even in building natural ice cellars and refrigerating plants with dry air circulation, it is possible to construct enclosing walls, partition walls in cold rooms, with Artpumice-insulating-concrete. It is thus possible to renew parts that otherwise would require insulation. 247 In the manufacture of Ottmann Artpumice it is possible to form sections in any size between 2 mm. and 5 cm. pieces. In this form Artpumice is also the lightest inorganic building material used in building, principally in deadening floors and for filling iron, tile or wooden ceilings. In large lecture halls, hospital dormitories and school rooms, when these have iron concrete plain ceilings which without hollow layers are good sound conductors, this insulating filling (covering) forms an excellent deadener and heat insulator. Taking the average dead weight of the Artpumice used for these purposes to be 180–200 kg., an insulating filling (or covering) 5 cm. thick weighs only 95 kg. per sq. metre. Besides this the filling material which is always employed dry, even in winter, is free of bacteria, and owing to its chemical composition, chiefly of siliconit, offers no nutritive base for microbes or disease germs etc. The technical university at Munich has certified that wood, iron, cement, gypsum, etc. are not attacked by the material composing Artpumice. The chief advantage of Ottmann Artpumice, wherever it can be manu- factured from bye-products, is that with it the architect can construct light insulating concrete parts of any desired formation or strength. In building roof houses for hotels it is possible with the aid of Artpumice to make a light roof construction of any form fireproof (such constructions can never be completely destroyed by fire), and so that upper rooms are insulated by the building material itself, obviating the necessity for building wood or iron frames. This must constitute a great advantage and saving for building in hot countries. In the erection of quick-drying, fireproof, sound proof, and light- weight partition-walls Artpumice with a binder can be used as insulating stones or slabs, securing for such walls the advantage of a slight dead weight. In building railway station enclosores, office rooms on open platforms, barracks, and in erecting the top floors of very high buildings with floors one above the other, Artpumice-insulating-concrete, because of its light weight and its power of insulation, would probably be of great assistance to architects in executing particular architectural features, since the constructions are cheapened, inasmuch as they combine building and insulating elements in one. An idea of the insulating value of Ottmann Artpumice is best given by the freezing room for game at the Ist International Sports Exhibition, Vienna, Department A, Class 12. Game was put into the freezing room at the end of May when it was started. It was kept fresh for months, until the close of the exhibition, and the Ottmann Artpumice kept the temperature in the cell below – 30 the whole time. This is shown by statistics of inner and outer temperatures taken four times daily. The cold necessary to preserve the game was produced by a refrigerating machine of the Brünn—Königsfelder Machinen- fabrik, working at first six hours and later for five hours, from 1 p. m. till 6 p. m. The resulting room temperature was —99 to —10° in the evening. After shutting off machine and conduits, the further controll of the temperature 248 and the preservation of the game depended upon the insulating material and the new kind of accumulator, in this case the Ottmann Artpumice. - The thermometer corresponding to that within the cell showed that at 1 p. m. the next day, that is 19 hours later, the cell temperatures were still between 3 and 49 below zero. This is a very good result for an inorganic insulator, and the practical application proved the correctness of the calculated assertion made at the opening of the exhibition. That the cell will not rise above 3° below zero, At the close of the exhibition the game was found to be perfectly fresh and palatable. Artpumice weighs loose, according to texture, 127 to 250 kg per mº, Artpumice is chemically indifferent, it has no harmful effect on wood, iron, cement and gypsum (Attestation of the royal technical university at Munich). Artpumice is absolutely fireproof and insoluble in water, also non- hygroscopic. Artpumice is employed loose as insulating filling, it being possible to attain equal densities (15 to 25%) with it, analogous to the insulating filling with groundcork. The compressive strength of Artpumice-insulating-concrete varies be- tween 10 and 55 kg per cm3. Such concrete with sand admixture has a compressive strength of be- tween 34 and 60 kg per cm3. The weight of Artpumice-insulating-concrete varies according to mixture between 600 and 1200 kg per cm3. With sand admixture this is increased to 1900 kg. - The transverse strength of reenforced slabs of Artpumice concrete with sand admixture goes up to 120 kg per cm3. - Artpumice-insulating-concrete mixed in the proportion 1 part Portland cement to 8 parts Artpumice has a heat conductivity of 0.19 (Attestation of the laboratory for technical physics at the royal technical university of Munich). Comp a r is on of thick n esses of m a teria 1 h a v in g the same ł he at in sul a ting power . CorkStone . . . . . . 10 cm Stucco . . . . . . . . 80 cm Wooden walls . . . 10–15 x Brick wall . . . . . . 100 x Artpumice, loose . . . . 12 > Pise concrete . . . . . 195 × Artpumice concrete . . . 25 x Stone wall . . . . . . 280 - (Calculated on the results of experiments carried out at the laboratory for technical physics of the royal technical university at Munich, and the aspecifications for determining caloric requirements" of the Austrian Ingenieur- und Architektenverein.) 249 Several Methods of Testing Cold Storage in- sulation, with Comparative Results. By W. M. Whitten, B. S., Pittsburgh, Pa., U. S. A. Until recently, there has been little or no data available, bearing on the heat conductivity of cold storage insulating materials, that could be relied on even for purposes of comparison, much less for use in designing insulation on a scientific basis. Many tests had been made, following vari- ous methods, but the character of such tests did not justify confidence in the results. In some cases, the method employed was obviously subject to serious possibility of error. In others, the conditions of testing did not correspond to the conditions of actual practice. Realizing this, and appreciating the immense practical value of ac- curate data on this subject, there was installed some years ago, at the Pitts- burgh factory of the Armstrong Cork Company, a thermal insulation testing plant, which is unique in Scope and epuipment. A carefully insulated testing room, so arranged that it can be easily carried at any temperature used in ordinary cold storage practice, a refrigerating machine, test boxes of ample size, delicate electrical apparatus to measure the heat loss, – these are the essential features which render it possible to conduct tests, under actual service conditions. -- The plant consists of the testing room twelve feet square by ten feet high, the walls, ceiling and floor of which are insulated with six inches of corkboard, so that any desired temperature as low as 0-degrees Fahrenheit can be maintained without variation by means of a three-ton refrigerating machine, electrically driven. The method employed in making tests is as follows: Inside of the testing room there is built a box of the material to be tested, measuring from three to four feet each way and affording, therefore, a radiating sur- face of from fifty to ninety-six square feet. Little or no lumber is used when the material is self-supporting, for it is desirable, of course, to eli- minate foreign material to the greatest possible extent, but when loose materials, such as granulated cork, shavings, cinders, mineral wool, etc., are being tested, a containing box of lumber has to be utilized. Before the test 250 box is sealed up, an electric heating coil and a small electric fan are placed inside, the holes through wich the wires pass and all joints of the test box being hermetically closed with a thin coating of hot asphalt. The test box is raised a foot above the floor of the testing room on light supports, thus obtaining air contact on every side. In the top of the test box, a long stem thermometer is sealed, the scale protruding above so that the temperature inside may be observed constantly during the progress of the test. In the testing room, another electric fan keeps up a constant circulation of air . about the test box, ensuring uniform temperature on all sides. A thermo- meter is hung in the testing room opposite the window so that the tempe- rature within can be determined by the operator without entering the room. A recording thermometer checks the readings thus made. When all is ready, both the refrigeration and the electric current sup- plying the heating coil and the fans are turned on and at least forty-eight hours allowed to elapse before any observations are taken, to obtain con- stant temperature conditions and to insure the uniform transmission of heat through the test box. The temperature of the test box is usually held at 90-degrees Fahrenheit; the temperature of the testing room at 10-degrees; the difference, therefore being 80-degrees Fahrenheit. This is purely an arbitrary matter, and in making check tests the temperature is usually varied; for instance, by holding the test box at 80-degrees, the testing room at 10-degrees; or, the test box at 85-degrees and the testing room at 15- degrees. After conditions have become constants, observations are made every ten or fifteen minutes, as may be determined upon, for a period of from three to five hours. The amperage and voltage of the currents supplying the heating coil and the small fan sealed up in the test box, respectively, the temperature of the testing room, and the temperature of the test box all are carefully read and recorded. During these tests the room, temperature is kept practically constant by regulating the expansion of the ammonia and the brine circulation; the box temperature by increasing or decreasing, as may be required, the amount of current supplied to the heating coil. The heat transmission is computed in the following manner: The average difference in temperature between the test box and the testing room, the average voltage, and the average amperage of the currents supplying the small fan and heating coil, respectively, are first determined. The test box is carefully measured and the mean area computed. With this data, by means of the following formula, the heat transmission per square foot, per degree difference in temperature, for twenty-four hours, in British Thermal Units, is readily computed: - 746 Watts = 1 H. P. 1 H. P. = 33,000 ft. lbs. per minute 1 Watt = ** = 44236 ft. lbs. per minute 746 251 778 ft. 1bS. = 1 B. T. U. 1 Watt – tº = 05685 B. T. U. per minute 1440 Minutes = 24 hours. Let F. A. = Average Amperage of Fan Circuit. F. V. = Average Voltage of Fan Circuit. C. A. = Average Amperage of Hoating Coil Circuit. C. V. = Average Voltage of Heating Coil Circuit. 1 Ampere × 1 Volt = 1 Watt Therefore (F.A.X.F. V.) + (C.A.X.C. V.) = Average Watts supplied Test Box. Let & D = Average Difference in Temperatu- re of Test Box and Testing Room. Then [(F. A. × F. V.) + (C. A. × C. V.) × 1440 × 05685 = D X Mean Area of Test Box = B. T. U. per square foot per degree difference in tempera- ture in twentyfour hours. Since the transmission trough any insulating material of uniform struc- ture is in inverse proportion to its thickness, the results thus obtained may be readily reduced to the standard one-inch thickness basis. All results are checked by means of several runs, and, usually by two or more observers working independently. The instruments with which the electric currents are measured are of the most delicate type and with their assistance the amount of heat conveyed into the test box may be determined with ab- solute accuracy. * At this plant a long series of tests has been made by our own engi- neers, not only on insulating materials but also on building materials, such as brick and concrete. Wit the data thus obtained, the heat lots through any type of construction can be computed accurately, and the proper thick- ness of insulation to install determined on a thoroughly scientific basis. For the purpose of this discussion, however, it will suffice to select the results obtained by testing one material — Nonpareil Corkboard — and use them throughougt in comparing the different methods. The average of twelve tests on Nonpareil Corkboard, conducted by capable engineers connected with the Armstrong Cork Company, gave its conductivity as 6.2 B. T. U. per inch thickness, per square foot per degree difference in temperature per twenty-four hours. These tests were later supplemented by those made by Walter Ken- nedy, M. E., a prominent consulting engineer of Pittsburgh, using the testing plant above described, in which he found the conductivity of Nonpareil Corkboard io be 6.5 B. T. U. per inch thickness, per square foot per degree difference in temperature per twenty-four hours. *--. 252 While having the utmost confidence in these results, it was decided to go one step further. Charles L. Norton, Associate Professor of Heat Measurements, Massachusetts Institute of Technology, Boston, Mass., probably the most eminent authority in America on the subject of heat transmission, was therefore requested to make exhaustive tests on Nonpareil Corkboard and other insulating materials. Professor Norton's experiments were begun in the summer of 1909, and continued over a period of five or six months. All his tests were made in the laboratories of the Massachusetts Institute of Technology. Five different methods were employed. * The following description of the five methods used by Professor Norton is taken from his official report of the tests: »The first and simplest of these methods, which is sometimes referred to as the ice-boy' method, consists in covering the outside of a metal box with the substance under investigation; then filling the box with ice and noting the rate at which the ice melts. Because of the uncertainty of kee- ping the entire box at exactly 32 degrees Fahrenheit, even though it be partially filled with ice, this method may lead to inaccurate results. Ho- wever, if proper care is taken to keep the box full of ice to retain the water formed by the melting of the ice and to make a suitable correction for the somewhat higher temperature of the top of the box with which the ice makes very poor contact, fairly accurate results may be secured. The method is liable to minimize the differences between two materials and to give values which are too low. By this method, however, the best value which could be obtained after repeated trials was Nonpareil Cork . . . . . . . . . 6.1 B. V. U.< »These figures are given in British Thermal Units transmitted through one square foot of material, one inch thick, in twenty-four hours, when there is one degree difference between the two surfaces.< »The second method adopted may be described as the oil-box' method. This is an adaption of the method used by the writer for a long time in testing steam-pipe covers. A box of metal approximately cubical in form is covered on all sides with the insulating material to be tested. It is filled with mineral oil and contains an electric heater and stirrer. By means of the electric heater any desired difference in temperature can be main- tained between the box and the room. The exact amount of heat lost by conduction through the covering of material under test can be determined from electrical input. This is measured by an ammeter and voltmeter. »This method enables us to work only at temperatures above the room in which the test is made, but it has been found that the efficiency of the insulation does not vary much Over quite wide ranges in temperatures, at least, over such ranges of temperature as are met with in modern refri- geration. Using this method, the following value was found after a very considerable number of tests: - Nonpareil Cork . . . . . . . . . 64 B. T. U.< 253 »The same difficulty which was met with in connection with the ice- box developed here, namely, the uncertainty as to the temperature of the top of the box. However, just as the errors of the ice-box method, all tend to make the measurements too low, so the errors in this method, namely the loss of heat through the stirrer rods, loss of heat through the supports evaporation of the oil and conduction through the overflow pipe, tend to make the results given by this apparatus too high. It is not believed, ho- wever, by the writer, that there is any great danger of this apparatus yiel- ding results which are inaccurate so far as the relative efficiency of different materials of the same thickness is concerned.< »The third method adopted, which may be termed the hot-air" box, was not unlike the previous method. Just as before the measurement of the heat supplied to cubical box was made by electrical method. The apparatus consists of a box constructed wholly of the material to be tested with only such light wooden supports as may be necessary for strength. In the case of the cork box none were needed. The box contains an electric fan, which gives us a means heating the air in the box thoroughly and uniformly and of determining the amount of heat necessary to maintain any predetermined temperature difference between the air in the box and the room outside.< »The box was constructed of the Nonpareil Cork, the thickness of the material being two inches. By means of an adjustable resistance inside the box and an auxiliary resistance outside, current and voltage could be main- tained at any desired point. The temperature of the air inside the box and in the room outside was measured with thermometers of great precision calibrated with care and known to be accurate to the nearest hundredth of a degree. These temperature measurements were also made by means of thermal junctions made of copper and nickel strips. These thermal junctions were also used in connection with the oil-box method described above. The electrical instruments for both of these tests were calibrated and known to be correct. The average result given by the hot-air" box method is Nonpareil Cork . . . . . . . . . 6.9 B. T. U. •For a long time the writer has made measurements of the relative Conductivity of heat insulators by what is known as the plate method This has been used by a number of investigators to determine the absolute conductivity of numbers of substances. An eletrically heated plate is placed between two sheets of the material to be tested, and outside of these are placed shets two hollow flat plates cooled by a circulation of water. Except for the edges, the heat which is lost from the electrically heated plate goes through the specimens into the water-cooled plates. This heat may be measured electrically, the temperature difference between the hot plates and the cold plates can ce readily measured by thermal junctions; and knowing 254 these factors, the area and the thickness, we may compute the thermal conductivity of the material under test.< * * * »The difficulty with this apparatus lies in the determination of the los from the edges, which is not only considerable but somewhat variable in amount, according to the nature and thickness of the material tested. A number of months of constant experimenting have enabled us to determine this loss from the edge and results obtained by this method, with this correction, compare very favorably with the data obtained by other methods; and we find the thermal conductivity to be as follows: * Nonpareil Cork . . . . . . . . . , 6.7 B. T. U.< The last method used, perhaps best described as the ,cold-air" box method, consists merely in substituting for the electric heater and fan, a box of cracked ice hung inside the 32-inch cube near the top. This will maintain the air in the box at a much lower temperature than the room outside and since the amount of heat required by one pound of ice in melting is accurately known, we can determine the amount of heat which penetrates the walls of the box by weighing the water resulting from the melted ice. This is carried outside of the box through a small rubber tube. The diffe- rence in temperature between the air inside and outside of the box is mea- sured by thermomers, and it has been found that with the ice box suspended near the top of the cube the natural circulation of air in the box keeps it at a very nearly uniform temperature. The result of these tests gives the following value: 2 Nonpareil Cork . . . . . . . . . . 6.0 B. T. U. Co m p a r is on of results. Ice-box Method . . . . . . . . . . . 6.1 B. T. U. Oil-box Method . . . . . . . . . . 6.4 B. T. U. Hot-air Box Method . . . . . . . . 6.9 B. T. U. Cold-air Box Method . . . . . . . . . 6.0 B. T. U. Flat-plate Method . . . . . . . . , 6.7 B. T. U. Average . . 6.4 B. T. U.< »It will be seen from an examination of the values of the thermal conductivity obtained by the different methods that there is no very great difference between the results obtained upun the same material by the several methods. In the opinion of the writer, however, these figures cannot be depended upon to give an absolute value of the thermal conductivity of the material as used in practice with a precision better than five per cent. In fact, the variations between several samples of the same material are likely to be as great as five per cent and oftentimes amount to ten per 255 cent. The figures tabulated probably approximate very closely to the actual amount of heat wich is lost per inch of thickness of insulation per Square foot in twenty-four hours when there is one degree difference between the sides of the sheet.< *The experiments were carried out over sufficient ranges in tempe- rature running from 32 degrees Fahrenheit, to 150 degrees Fahrenheit, to enable us to be certain that the thermal conductivity of the materials does not vary much with the temperature. For instance, tests made between 32 degrees and 70 degrees give practically the same results as those made upon the same material between 70 degrees and 100 degrees. Further, the writer has recently made a study of the variations in thermal conductivity of a number of substances from zero up to 2000 degrees Fahrenheif and in view of these results it would be surprising if the variations in thermal conductivity between 32 degrees and 100 degrees should be found to be large enough to have any bearing upon this discussion.< >The tests upon the ice-box are complicated by the fact that the pro- portions of corners to flat sides is lager thar in the case of the 32-inch cube used in the hot-air method. This gives us some uncertainty as to what we shold adopt as the real area of the insulation. In all cases, however, the mean area has been adopted, that is, the area of the surface taken at the middle of the thickness of insulation.< »For a number of a reasons it has seemed that the most reliable methods were the electrical method, using the hot-air box; and the cold- air box method. It will be seen that these two methods enable us to work readily upon a specimen containing fifty square fee. By using the electric heater we may have a higher temperature inside than outside. By substitu- ting the box of ice we may reverse this temperature condition. By the elec- trical method we measure our heat in electrical units with delicate instru- ments and in the other method we measure the .heat merely by weighing the amount of ice melted. In the one case the air is forcibly circulated by fans; in the other we depend upon the natural circulation of the cooled air; yet these two methods give us practically the same value for the amount of heat transmitted and it is the opinion of the writer that these two methods may well be apopted for tests of this sort of insulation.< ->The electrical flat-plate method is undoubtedly capable of yielding the most precise results. It is quite possible to duplicate observations by this method well within one per cent, but the uncertainty of the apparatus must have in order to be usable for specimens two inches or more thick, and the accompanying uncertainty as to the heat lost from the edges, make the apparatus more suitable for determinations of the relative than for the ab- solute conductivity.< It is interesting at this point to note how closely the results obtained by the engineers of the Armstrong Cork Company and Mr. Kennedy, using 256 *~. the same method and apparatus, are confirmed by Professor Norton, using five different -methods. The average results are as follows: Armstrong Cork Company's engineers . . 6.2 B. T. U. Walter Kennedy, E. M. . . . . . . . 6.5 B. T. U. Professor Norton . . . . 6.4. B. T. U * * g º 'º º 257 The Cooling of Electrical Machinery. By Paul Gasnier, Head of Electrical Department, Chargé de conéfrences, at the School of Industrial Physics and Chemistry, Paris. In Electrical machinery for all purposes, generators, motors or trans- formers, as in all apparatuses for the conversion of one form of energy into another, a certain part of the power absorbed inevitably escapes and con- stitutes what is known as the loss. All the energy corresponding to this loss, whatever its cause, is converted into heat. This results in the machinery being heated up until the quantity of heat produced equals the quantity dissipated, in the same time. The dispersion of the heat is effected, thanks to the excess in temperature of the machine over the surrounding air, partly by convection, partly by radiation and partly by conduction. For a long while no special arrangement has been made, in construc- ting electrical machinery, for accelerating the cooling. The machines, gene- rally, produce very little heat. Commercial competition, restrained at first, has been continually on the increase with the number and importance of electrical installations; which has stimulated the makers of machines to get the maximum possible amount of power out of them. The principles of construction have not been appreciably modified for ten or fifteen years, neither has the quality of materials changed, except for the steel plate used in the construction of transformers; and in the mean time the power of the machines has considerably increased. Two chief methods have contributed to this result. On the one hand machines have been made so as to assure good cooling, and for this purpose they have been provided with ventilation passages divided into cross partitions and requiring ventilators. On the other hand the amount of heat allowed has been increased. It might also be noticed that the working temperatures allowed in the machines have been constantly on the increase, and it seems as if the limit has now been reached, In a report recently given by Mr. Brunswick to the International Society of Electrical Engineers (November 1899), on the Temperatures allowable in dynamos, and methods of determination thereof, from the work 17 258 of the first section of the committeeg, he has stated the following principle: »That a temperature of 100° C. is a safe limit for continuous and indefinite working. It seems, in fact that cotton can remain at this temperature for a long time without becoming appreciably changed, but the same cannot be said of higher temperatures such as 110° or 120° for instance.< This narrow margin of 10° to 20° outside which the durability of the machine would undoubtedly be compromised, may seem insufficient, and it is certainly preferable to endeavour to increase the efficiency of a machine by means of cooling, so as to work at the lowest possible temperature. The Transformer, consisting as it does of stationary parts, is of all electrical apparatuses the one for which cooling has been studied most. Transformers are immersed in petroleum contained in metal vessels provided with ribs for cooling, and some of which are provided with separate radi- ators; the oil is caused to circulate by variations in density. Cooling is sometimes completed by a circulation of water in a special coil of pipes. In spite of precautions taken in machines to make the circulation of air more active, the energy which it is possible to disperse without exceed- ing the heating limits allowed, still remains very limited in value. Hence high powered machines must of necessity be constructed so as to have Small losses, that is to say, so as to have an excellent output. Commercially a very high output is not always the most advantageous. A typical example of this is furnished by electric wiring for the trans- mission of energy. The output is higher, that is to say, the loss is lower, as the wire is thicker, other things being equal; on the other hand the outlay and interest on the capital employed, as well as various other factors, in- crease proportionally to the section of the conductor. Hence the annual cost is at a minimum for a certain section of cable, that is to say for a certain output. This simple instance, easy to express algebraically, has ori- ginated the well-known economy formula of Lord Kelvin, given before the British Association in 1881. It is well-known that electrical power stations are in a special position with regard to utilization of material. The power of the machines is enor- mous compared to the power lost. With the exception of electric traction, the energy lost often does not correspond to that produced by the machines working for only one tenth of the total time. It would be profitable to use a wasteful material if thereby a small percentage of apparent loss might be offset by a greater saving elsewhere. In fact there are machines of the same power and having different outputs; and the cost of operating thus increases with the output. The question of the choice of a machine may be put somewhat in the same way, but in a form less simple to express algebraically than for the choice of a cable; it is not the machine with the highest output which is the most profitable. It appears difficult to work at temperatures higher than those usual at present, and even with the use of new insulating materials, elevation of the 259 temperature would have other disadvantages due to expansion. At least, until substances are found which are better conductors than copper, or more permeable than iron, the only means of increasing the power of a machine is to increase the current tension in the copper, and the induction in the iron, which increases the loss in any given machine. The loss increases more quickly than the current tension and the induction, that is to say more quickly than the power, which means lowering the output. Lowering the output is not always a disadvantage. Since the maximum amount of heating is now permissible, the efficiency must necessarily be increased by cooling. The ventilation passages and ventilators in large machines are becoming insufficient; these must therefore be provided with refrigerating pipes, through which water or even a refrigerating liquid circulates. It would be advantageous for the moving parts to circulate previously refrigerated air trough them instead of air at the ordinary temperature. -- This short paper on the cooling of electrical machinery, a matter which, at present, is not considered in connection with refrigerating machinery, is written simply to point out that the ever increasing importance of the question of cooling electrical machinery may possibly result eventually in a new application of refrigeration, 17% NEW AND IMPROVED ARRANGEMENTS IN THE INSTALLATION AND OPERATION OF ICE FACTORIES * By VAN RENSSELAER H. GREEN, New York City, U. S. A. - The first system of ice manufacture to become established in the United States was that of “Can Ice.” This was udoubtedly due first to the demand for a Hygeia ice and second, to the lack of familiarity with the principles of other processes. The system of can ice making is found in the older plants, de- manded a large steel tank holding 14%. 300 lb. ice cans per ton and 300 ft, of I*4-in. pipe. The pipe was set in vertical stands (either 6 or 9 pipes high) between each row of cans and extended the entire length of the ice tank. An ammonia expansion valve fed between 900 and 1000 ft. of pipe. The exhaust steam from the engine driving the refrigeration machine as well as that of the auxiliary apparatus, passed through a large coke filter to the steam condenser, where it was condensed. From . the condenser the water entered the reboiler to be freed from air, and then passed through a counter-current double pipe distilled water cooler to be cooled by water obtained from the same source as that used over the ammonia condenser. After being cooled, the distilled water was allowed to flow by gravity through a charcoal filter before entering the ice cans. Under these conditions the distilled water when ready for freezing had a temperature of about 70°F. Since many hours were required for the water in the brine tank to reach 32°F. and for the ice block to freeze solid after the 32°F. was reached, the builders of such plants were forced to use 16 cans per ton. As our cities grew and became better populated, land increased in value and the space required for an ice plant on the 16 can per ton basis was too extensive from a financial standpoint. Naturally then, the next step was to find some method of lessening the number of cans required. Experiments in reducing the temperature of the water entering the cans have proven that 12 hours time and frequently longer is consumed in lowering the distilled water from 70° to 40° F. and that if this can be 261 done by some means outside of the freezing tank, great savings in the number of cans will be made. Under the old system, 52 hours were re- quired to freeze solid a 300-lb. can in a brine temperature of I4°F. If with a reduced water temperature the same block can be frozen in 40 hours we need only 12 cans per ton instead of 14%. Nowadays nearly all new plants are erected on this basis with some means for cooling the distilled water to 40° or less. Sometimes this is accomplished by passing the return gas from the freezing tank through a steel tank containing the water; sometimes by an individual expansion line to a double pipe water cooler. Both of these systems have their weak points. In the open tank through which the return gas passes, there is danger that the water will absorb air thus producing opaque ice, and also that the submerged pipe will be unequal to the task of cooling. This type of cooler seldom lowers the water temperature to less than 42°F. On the other hand, the objec- tion to the double pipe type is the great likelihood of freezing and split- ting the pipe, because of the irregular flow of the water to the cans. Nevertheless, a forecooler of the latter type will frequently permit of water entering the cans at a temperature as low as 34° F. and accord- ingly will show a greater saving in the number of cans required. When the ground space for ice plants using a smaller number of cans was accordingly decreased, it made possible the erection of many plants in large cities and stimulated a healthy growth in the ice business which is very satisfying. From an operating standpoint, however, the reduction in the number of the cans presented difficulties. These arose from the fact that it became necessary to more closely regulate the ammonia expansion valves because with fewer number of cans, there was a corresponding reduction in the quantity of piping per ton. Moreover, as the ice almost immediately formed upon the 'sides of the tank in an insulating layer, the liquid in the coils could not become gasified by absorption and was likely to pass through the entire coil and enter the compressor cylinders in a liquid state, thereby reducing the capacity of the machine and causing trouble in the stuffing box by irregular changes in temperature. Frequent experimenting on the part of the manufacturers to design a form of separator, which would effectually separate the liquid from the gas and, when separated, to return the liquid to the tank coils to do useful work, have brought forth a new improvement in ice manufacture. The latest plants have the bottom run of all freezing coil stands con- nected with a header, which, in turn is connected with the bottom of a large separating tank which joins with a pipe passing through the separ- ator on its way to the compressor. Any liquid ammonia which enters 262 the side of this separating tank falls to the bottom to be returned to the freezing tank, while the spent gas passes off the top to the compressor. Anhydrous ammonia from the condensers previously cooled by the re- turn gas is fed directly into the separating tank in quantity sufficient to maintain in the bottom of the tank a constant level, sufficiently high to insure the thorough drenching of the freezing coils throughout their entire length. This level is first obtained by experiment and when once found is maintained constant by means of a double glass gauge glass lo- cated in the side of the accumulator. When therefore, only one ex- pansion valve will control any number of freezing coils, and, once pro- perly regulated will maintain a constant level in a single accumulator, it was possible to reduce the pipe required per ton from 300 to 225 ft. of I3/4-in. pipe. . So far as the writer has been able to observe, there is no marked difference in the rate of heat transferred per sq. ft. when the pipe is filled with liquid ammonia or when the old system is used. The gain attributed to this new arrangement is only due to the possibility of keep- ing all of the pipe surface at work at the same time. Further, than this it forces greater efficiency out of the compressor, since the return gas Rept in a saturated condition by constant contact with the liquid am- monia when entering the compressor does away with one of the big evils of the old time system, that of suction superheat. Keeping pace with these marked improvements in the operating of the freezing tanks came similar changes in the manner of handling the distilled water. The passing of the exhaust steam through a coke filter was discontinued because of the enormous water losses due to con- densation and also to the difficulty of finding at all times a grade of coke adapted to the purpose of freeing the steam from the oil. In its place now we find centrifugal oil separators or oil separators filled with baffle plates for the separation of oil from steam on the principle of centrifugal. force. For the economical production of ice, compound condensing steam engines are now being furnished to drive the ice making machine and the water shortage due to the use of more economical machinery is made up by multiple effect evaporators either working under a vacuum or on live steam direct from the boilers. Under the old system where it was considered unusual to manu- facture 7 tons of ice per ton of coal, now many plants are in existence making as high as IO tons of ice per ton of coal and sometimes even more. All of this is due to a more scientific method of building ice plants and to a simplification of operation in order to bring the means of control down to the level of the engineer who must produce the results. 263 Nevertheless, the growing demand for an even cheaper method of making marketable ice than is found in the can ice process has brought forth recently the plate ice system. In the past the one great point against the practical working of this type has been the impossibility of producing uniformly straight ice without impairing the compressor efficiency by an excessive liquid ammonia feed. Plate ice differs from can ice manufacture in the fact that a vertical coil is covered with sheet iron and immersed in a large tank of water, when the liquid ammonia is expanded into this so-called plate the ice forms a slab on each side which increases in thickness until it reaches about I2 inches in six days when working under processes similar to those commonly maintained in the can ice process. When these two great plates, one on each side of the freezing coil, are of sufficient thickness, the supply of liquid ammonia is shut off and the ice thawed from the freezing plate by a hot gas connection between the coil and condenser header. The ice when thawed is then lifted from the tank by means of a crane, taken to the cutting table and cut into the regular 300-lb. size by a steam cutter or an electrically driven saw. In the ordinary plate system there are as many plates in each tank as the daily capacity of the plant requires and usually from six to seven tanks for the necessary 6-day freezing time. Each plate has its ammonia expansion valve while the return gas enters a com- mon return header and passes through an open tank water forecooler before entering the compressor. In spite of its many advantages, the one great difficulty in the system is the making of uniformly straight ice without an excessive feed, but this has been accomplished by the application of the principle of the Flooded System. In the plants of older construction, the steam cutter most com- monly used for cutting up the plates consisted of a grid work of 14" strip iron, sufficiently large to cut at one time six 300-lb. cakes. Along the bottom of this grid was fastened small copper tubing into which steam was admitted. . While the cutter was resting on the surface of the ice, the steam, acting under the weight, melted its way down through the ice until it cut clear through, when the cutter was removed and placed upon another section of the ice. This arrangement of cutting proved very expensive because of the excessive meltage, which was due to the pressure of this hot water on the ice surface. Accord- ingly it was abandoned in favor of electric saws. The constant atten- dance, however, which the directing of the electric saws required, and frequent trouble with the electric devices caused by the dampness, drove the manufacturers in search of simpler method of dividing 264 *--, up a large plate into the desired blocks. A recent invention for this purpose has been applied with good success. It consists of a steam cutter sunk into the cutting table and raised up through the ice by means of air jacks located beneath. Though the steam cutter is of the same design as of those used on the old plants, there is less waste in operation because the cutting from beneath permits all the meltage to flow away from the ice cake. Formerly when the cutting was done from above, the slot caused by the hot water was as wide as I-4%". With the new cutter, however, the slot is no wider than the steam pipe—never in excess of 1%." and usually less. Moreover, as one man can pull and harvest as many as 60 tons of ice in 6 hours, this new cutter has also simplified the handling of the plant. To reduce the ground space required for the location of a plate ice plant, it has become necessary to design as large a plate as possible, so that it is not an uncommon sight to witness a cake 20' x 12" x II", being thawed, lifted to the table and cut up by one man with little more effort than that required with a 300 lb. cake. * Plate ice is especially noted for its clearness and uniform ap- pearance and is becoming more and more popular in America for this reason: While the first cost is not excessively greater than that of can ice, the manufacturing cost is considerably less. With an ordinary grade of soft coal it is comparatively simple to manufacture I2 tons of ice to the ton of coal, and there are plants in existence making as high as I4. From the standpoint of purity there is at present some disa- greement, but recent reports from Washington show little cause for ar- gument, as both products are considered as almost equal. Numerous patents have sprung up in the field of plate ice manufac- ture based upon the saving of ground space and freezing time. One plan becoming popular is that of fastening to the freezing plate strips of iron extending therefrom about 6” and placed vertically on the plate on 22" centres. The idea of these strips is to form a better connection between the plate and ice and thus lessen the freezing time. When frozen and thawed off, the cake is cut through the slot left b the strip into the standard size of 22" x 44". § The Humes system of can ice making plants differs from the stan- dard ice can making system in so far as the ice cans used are four times the size of the commercial can used for the standard system. The reason for making these cans so large is to be able to cut the ice cakes through the core in the ice into four blocks which correspond to standard measurements, that is to say the ice cans are made large enough so that they can produce four 300-pound blocks if cut up as 265 indicated after the cake has been released from the ice cans. With the Humes system of making ice no distilled, or filtered water is neces- sary as the water in the cans is agitated by means of compressed air introduced into the water by a vertical pipe projecting into the center of the can and ending near the bottom. * Another device for lessening the required floor space consists of a header into which are screwed on 12" centres a number of 2" pipes extending the depth of the cake. Inside of the 2" pipe is placed a 11/4” pipe, cold brine is next pumped into the I*/4" pipe, returning through the 2" pipe. After three days time, 12" ice is frozen around these pipes. When ready for harvesting, the line from the brine pump to the header is disconnected and ice together with the pipe removed from the water to the cutting table. There warm brine is circulated through the pipes to loosen them and the ice, intact, is cut into 300-lb. cakes. Though the holes in the ice can be filled with water and frozen, they are generally left open. With this arrangement of 36 hour freeze in- stead of 72, a plant of one half the ground space can be built, and the ice tank turned over twice a week instead of but once, so the system is being favorably considered in cities where space brings a high pre- mium. - In this connection it would be well to discuss another process un- developed as yet, but potentially great. About 15 years ago, Major Holden built the first Regealed ice making plant, which presented so many mechanical and commercial difficulties that the idea has not grown rapidly. Nevertheless, it fits in so well with the demand for small space and cheap installation that further experiment will no doubt produce a more complete machine. In the original design, there is a tank full of water containing a drum insulated on the outside into which liquid ammonia flows at a suction pressure from 5 - I5 lbs. per square inch gauge. As the drum revolves, the ice formed is scraped off by a knife which runs the full length of the drum. A helical screw then Sweeps the floating ice to one end of the tank into a rotary pump, from which it is driven into the regealing cylinder operated by a hydraulic compression cylinder. The regealing cylinder contains a rectangular piston, while the casing is of the same cross section perforated to allow the passage of water. When pressure is applied to the chips in the cylinder on the forward end, it first drives the water out of the holes and then increases to about 500 lbs. per sq. inch, thereby forming the chips into a solid block. As soon as this is accomplished and pressure relaxed, the block of ice is pushed out from one end of the press. By careful control of the ice chips, 266 each block can be made uniform in weight and size. Nevertheless, there are no means at present of keeping the air from getting into the ice, so the necessarily opaque product is not marketable for house- hold purposes. For simplicity of Operation and cheapness of con- struction this system has no equal and now that the ice press has been perfected, it promises well. sº When we look back over the past 30 years and consider the rapid development of the ice houses, insulated with saw dust and tar paper, into the storage rooms furnished as we now see them, it does not take much imagination to foretell the perfecting of the equipments in the near future. Nothing has been more remarkable in the mechanical world than the growth of a new science out of a branch of Ther- modynamics. Correspondingly, wonderful has been the almost casual growth of the low pressure side of the industry. While the attention of the scientific world has been centred on the compressors and engines, the assisting machine has changed and developed until now it has reached a high order of usefulness. To be sure, the later changes have brought with them difficulties which we or another generation must solve. Nevertheless, the pioneers have blazed a wide trail which will lead, sooner or later, into an ultimate perfection on designs of the freezing systems. * 267 Mr. Nicolaus Borodine Conseiller d'Etat etc. in St. Petersburg describes fully, in two papers, the position of the Refrigeration Industry in Russia. These papers show in their conclusions that capitalists and contractors would find an immense field in Russia, for the Refrigeration lndustry. ~. The Russian Committee of Refrigeration at St. Petersburg, Place du Palais 8, furnishes any information desired. The papers mentioned, which are printed and were distributed by the Congress, may be had gratis on appli- cation to the above named Committee. 268 The technical intervention of national cold societies in the building and management of cold plants. By Ingénieur Karl Heimpel, factory director, Vienna. Question 10 in the programme reads: Intervention of national cold societies in the technical preparation of contracts, the supervision of the building, the trials and periodical exami- nation of cold producing plants; advantages and conditions of such inter- vention; proposals for their definitive regulation by the international asso- ciation. - We must examine this question in two directions: 1. Whether the action required in question 10 of societies serves and furthers the objects of the society; 2. Whether the national cold societies, on the strength of their organi- sation, are apparently Suitable to effect such work. According to the statutes of the national cold societies and of the International association the object ot these societies consists in x the furthe- rance of scientific, technical and industrial work directed to the production and application of cold, and all the connected interests of commerce and trade ; further in the encouragement of personal relations between its members.< The intervention demanded refers in the first place to the settlement of contracts for supply or to preparations for such settlement, that is, to judging the various projects, alteration proposals, criticism of estimates, drafting final letters. The organs of the Society have to decide between a number of various machine systems which are different theoretically and still more so in their practical execution. Yet all these systems command their markets by being able to refer to certain actual or suppositious ad- vantage, or by cheapness of price compensating for eventual inferiority. In making contracts, however, so many local matters besides quality have to be considered, as for instance, utilising of working power, terms of payment, simplification of transport and mounting, engagements between buyer and 269 supplier, etc., that in fact only a commercially trained technicist can gauge the correct medium on which a settlement satisfactory to both parties is pos- sible. The organs of societies must not, however, support their judgment on estimates and suppositions, if they do not wish to run risks of the most violent attacks of the defeated competitors. They can only proceed upon in- disputable experimental data or other absolutely reliable facts. Thereby, how- ever, they eliminate all formerly suggested, often very important side matters for the Ordering of a plant, and can only assist one or several machine systems to success, which have hitherto given relatively favourable experimental data, or most entirely satisfy the stipulated standards. In this necessary proce- dure of the organs of societies there does not lie any furtherance of the object of the society, but, on the contrary, a hindering of it. The society hinders the development of competing cold systems to the advantage of Some accepted as the best, and will even hinder the further development of these best systems as it only compels them to fulfil the demands limited by standards, but does not compel them to progress. t This process might in many cases actually prove more unfavourable than is here depicted. Experience shows that the societies must be ruled by some prominent leader if they are to live. If, now, this leader has a Special Sympathy for a particular system, he will drive the society involun- tarily in this direction, and the society soon finds itself on the way to a one-sided representation of interests. We must therefore recognise that through the intervention of the Society in the settlement of contracts, neither is the purchaser completely served nor is the development of the respective machines and machine in- dustries assisted. The Supervision of the erection of buildings, working experiments, and the periodical examination of cold producing plants can hardly be judged from the stand-point of the general furtherance of cold technics. They are functions in the interest of individuals which exercise little influence on the development of cold technics, and the question has only to be examined whether the Society on the strength of its organisation is in a position to take over these functions. *. * - It is not uninteresting to consider how such intervention stands with respect to the before mentioned further object of the society, namely • the cultivation of personal relations among its members. First it is to be feared that civil engineers, whose life-task consists in the execution of above functions, would avoid the society and fight against it. A valuable ele- ment in the life of the society would thus be lost. Further it will be unavoidable that those machine factories which are Seldom or never ap- proached for deliveries will, together with all their adherents, violently oppose the society. This, again, would result in a not inconsiderable weak- ening of the societies. Finally even among the remaining members the technical judgments of the society's organs would cause opposition, and 270 lead to many divisions. The foregoing, therefore, unfortunately leads it to be expected that the tasks suggested are not calculated to further the personal relations among members or the inner life of the society. An enquiry at a number of technical Societies gave an entirely negative result; all the socie- ties declaring that they could not undertake such far-reaching interventions, Then comes the second question, whether the national cold societies, on the strength of their organisation, are suitable to undertakn the functions desired in question 10. -- The national cold societies command such a quantity of technical authority, that without doubt, they could fulfil the requirements of these tasks to a prominent degree. Just this uncommon combination of all tech- nical knowledge may have led to the putting forward of question 10. Reflections only exist against the legal form under which these functions should be exercised. The functions cannot, of course, be gratuitous. They must form a source of remuneration for the society, since the society must also pay its organs for their pains. Here, however, the society, comes under state supervision both as regards its legal rights and as regards its income; it becomes an industrial undertaking and thereby changes the foundations of its existence. - e It must further be considered that in spite of prominent executive functionists art-errors are not impossible, for example in the Supervision of buildings. Who would be responsible for the consequences of these faults? Legally every member. This responsibility would, however not suit many members, especially those who stand in looser connection with the cold industry. These disadvantages which must not be underrated, could be avoided by the national Societies founding separate organisations, which could undertake, entirely independently, the objects laid down in question 10. These organisations would have to bear all legal responsibilities and all expenses, and also to be as financially independent as possible. In the boiler revision societies we have good examples for such orga- nisations. The revision societies have also chiefly sprung from the initiative of technical and industrial societies. They arose from the desire of con- ducting boiler trials and examinations not through state authorities but through a technical specialist who could at the same time be a friend and adviser to the industry. These revision societies have fulfilled an admittedly blessed activity but they avoid generally influencing the traffic of machine factories with customers, thus omitting the most important point of question 10, from their programme. The existence of these revision societies is chiefly secured by the legal compulsion of boiler examination and trials. It is very doubtful in spite of their great popularity, if they would be able to continue should this legal compulsion cease. From this suggestion it must be decided, that similar organisations in the cold industry are less capable of existence, as the support of legal compulsion fails them. A further circumstance appears against the formation of Such organisations. 271 The sphere of revision must be a fairly limited one for many reasons, but especially on account of expense. The number of plants to be exa- mined in a small district is relatively small, especially on the continent, and is in no proportion to the exceedingly great number of boilers that are under the boiler society in an equal district. The expenses of the separate revision would for this reason be improportionately high, as the Society can only leave this responsible work to first class functionaries. Experience shows that the owners, unfortunately, estimate the value of such revision far too low, at the present day, and from this cause the number of objects in a revision district is again greatly reduced. We must therefore confirm that the national cold societies, on the strength of their organisation, do not seem to be suitable themselves to undertake the functions required, in question 10 to the fullest degree, and that the formation of separate organisations for this purpose also offers, at present, but little prospect of success. In spite of these variously founded reflections it is not necessary that the national cold societies renounce all idea of any activity in the sense of question 10, and such renouncement lies in no way in the interests of the society, yet it appears requisite that the Societies limit themselves only to that action which they can execute in the best manner without undertaking depressing responsibilities, without threatening other authorities in their exi- stence, and without having to retire from the frame of their present orga- nisation. As regards the extent of this activity I would like to lay down the following suggestions: 1. The Society is ready to work out standards for the delivery contracts of cold plants in which especially the guarantees would be brought into agreement with the definitions and methods of trial aimed at by the cold societies; an influence on sources of Supply, construction and prices is not undertaken by the society. - 2. If at the order of authorities and public corporations plans and constructions have to be certified, the society will delegate experts for this purpose. 3. The Supervision of building work and the permanent revision of . cold plants is the task of the specially appointed engineers and not a matter for cold societies. 4. On demand the society sends expert delegates for the experimental examination of cold plants, eventually also for the purpose of undertaking guarantee trials. . 5. The society places legal experts at disposal of the authorities on demand and also constitutes, if required, a court of arbitration for the arrangement of differences outside the courts of law. The intensity with which the various nations devote themselves to cold technies and the density of the distribution of cold plants in definite districts have considerable influence on the judgment of question 10, here discussed, and the objections and limitations raised, especially in so far as the organisations are considered, will probably be chiefly applicable only for continental Europe. England and America show a far more intense acti. vity, as regards the use of cold plants, than does continental Europe, and for this reason question 10 will probably find another solution. It there- fore seems impossible to solve this question in a single manner, too large a number of local conditions influence this solution. For this reason I suggest:... It is left to the national Societies, to undertake a regulation of their activity in the sense of question 10, in proportion to the local conditions. 273 Concerning the Economies and Statistics of the Utilization of Heat in Mechanical Refrigeration. By Lieutenant Colonel D. Jakowleff, Engineer, Lecturer at the Academy of Engineers, St. Petersburg. To-day, thermal economy, (whether in the application of heat for power production, or power for heat extraction,) in connection with the various technical means at the disposal of engineers, demands a thorough preparation of the methods of a rational projecting of electrical, water- supplying or refrigeration central stations, independently of their prime objects. The aim of each project is by a rational choice so to combine these technical expedients, suitable to each individual case, that the working ex- penses of the plant are kept as low as possible. The necessity for a consequential and systematic application of eco- nomy to every branch of machine management has been most distinctly proved, so far, in the sphere of power production. Thirty or forty years ago, when there was only the steam engine, the whole question resolved itself into the best possible construction of the machinery. It is a different matter now. In the first place the question of the cheapest cost of power production has been rendered much more complicated by various factors, such as competition, dearer labour etc., as also centralization of the under- taking; secondly the large variety of types of motors has brought about the necessity of choosing the most suitable type. The present situation may be best illustrated by an example. Let us suppose that an electric plant of 1000 KW capacity is to be built; further that the kind of current is stipulated, thereby fixing the type of electric equipment; the question remains: what motor Steam piston, turbine, expansion or Diesel? First of all, the general determinative factors must be settled; e. g., whether any other purposes may be served in connection with the production of current; such as, heating or drying, when the possi- bility must be considered of making use of the exhaust steam. It is plain that if in such a plant the machines do not exhaust the steam into a con- denser their work will be less economical, but the advantages of the simul- 18 274 taneous performance of other work may be so great as to increase the total useful output of the station. If calculation actually shows that such com- bination is advantageous, it must next be compared with others; for example, the obtention of mechanical energy with Diesel or expansion motors, and with special boilers, types of motors, steam turbines with counter-pressure, with intermediate steam discharge, exhaust steam turbines, etc. Space here prohibits a closer examination of the combinations just mentioned, and to explain the above reference to the importance of economy, the most simple case may be cited, in which no side issues are to be considered, but only the best type of motor chosen for the production of electrical energy. Naturally, in such comparative estimate, not only work- ing expenses but also interest on capital, depreciation, repairs, etc. must be taken into account. The advent of combination plants has thus led to new TABLE I. 1. Turbogenerator 1.000 Gas Dynamo 1.000 KW Diesel Dynamo 1,000 RW a R. 90 per a R. 110 per KW =110.000 KW a R. 130 per ECW = 90.000 KW =130.000 2. Condenser with pumps Gas generator a R. 30 Gas and air conduits, a R. 25 per KW = 25,000 per KW = 30.000 mufflers, etc. = 6.000 3. Boiler with super- Starting mechanism = 6.000 Reserve pieces = 7.000 heater and armature - a R. 40 per KW = 40.000 (Capital in vest ed): Steam turbines. Gas generators. Diesel motors. Water cooling system with pumps and con- . Steam conduits, water Engine room 0-75 sq. conduits, feed pumps, : m. per KW a R. 50 = 2.800 etc. = 5.000 duits = 10,000 5. Reserve pieces = 2.000 Gas and air conduits, Foundations, canals, mufflers, etc. = 4.000 etc. = 15.000 6. Engine room and Reserve pieces = 7.000 boiler room 1 sq. m. per KW a R. 50 per sq. m. = 5.000 7. Foundations, canals, Engine room 1 sq. m. etc. = 8,000 per KW a R. 50 == 5,000 ---. 8. Shaft, immuring, Foundations, canals, etc. = 10.000 etc. == 15.000 † total 185.000 187.000 162,000 / Depreciation in 3% of Depreciation: Depreciation: f original cost: §§ 1, 2, 3, 4, 5–8%; §§ 1, 2–8%; $ 4, §§ 1, 2, 3, 4–7%; $ 6, §§ 7, 8–3%. 5–3% , 7, 8–3%. Repairs in 7% of Repairs: Repairs: original cost: § 1–4%; $ 2, 3—3%; § 1–4%; $ 2–2%; §§ 1, 2, 3, 4—3%; $$ 6, §§ 4, 5–2%; $$ 7, §§ 4, 5 – 1.5%. 7, 8–1.5%. 8 – 1.5%. , 275 We obtain for comparison: TABLE II Steam turbines. 1. Depreciation and Re- pairs (according to the above 7%% stand- ards): 17,000 2. Interest on capital invested (5% per ann.): 9.250 Comparative Statement. A n n u a 1 ex p en s es: Gas generators. 19.500 9,350 The operating expenses proper: (10 hours, 300 work-days per ann.; Coal 11 Rbl. per ton; Anthracite 16 Rbl. per ton; Naphtha 30 Rbl. per ton.). Steam turbines. 3. Fuel: Steam consumption 7.5 kg per KW hour: Supplementary ex-. pense (Condensation, etc.) 18%. Total Rbl. 1.18 × 1000 " X 7.5 × 10 X 300 X 1 75x1000 X 11 = 42,000 4. Lubricating and clea- ning material: 0-28 gr. per KW hour at an average price of cylinder and machine oil of 3-5 Rbl. per pood (0-22 Rbl. p.kg.); cleaning material 100% of the cost of lubri- cating. Total Rubel: 2 X 1000 × 0-28 X10 X 300 X 0-001 X 0.22 = 5. Water: Feed water for boiler, at 2 Kop. per cu. m. Cleaning, Rbl.: 1000 X 7-5 X10X300X0-001 X 0.02 == Cooling water, 25 times the feed water quan- tity, at ‘Is Kop. per cu. m., R.bl.; = 6. Labor per annum, Rubel: 6,000 400 450 Gas generators. Anthracite: 0.55 kg per KW hour: Supplementary expense 10%. Total Rubel: 1-1X1000 X 0.55 X 10 X300 X 0.001 X 16 = 29,000 2-2 gr. per KW hour. 30% of the lubricating costs: 1-3X1000 X2-2 X 10 X 300 X 0-001 X 0-22 = 1.900 Cooling water, for ge- nerator and scrubber, total 35 litres per KW hour, at ‘l, Kop. per cu. m., Rbl.: 1000 X 35 X 10 X300 X 0-001 XO-005 = 525 Diesel motors. 17,000 8.100 Diesel motors. Naphtha: 0.28 kg KW hour: Supplementary expense 5%. Total per annum Rbl.: 78,000 2,800 5,000 65.400 Total Rubel : 1:05}{1000 X 0-28 X 10 X 300 × 0.001 X 30 = 26.500 1,900 Cooling water, 15 litres per KW hour, at ‘l, Kop. per cu. m., Rb1. : 1000 X 15 X 10 X300X0-001)×0.005= 225 5,000 58,700 18% From the resulting totals (78,000; 65.400; 58.700) it is evident to which type preference should be given in the instance taken, if the question is considered apart from other influences, such as, possible combination of the arrangement of a power station with heating etc., and from other circum- stances, such as the employment of sufficiently experienced operatives (for Diesel motors), etc. - The calculation just given has been simplified to the utmost; neither has the possible change in the number of hours of work been considered, nor the degree of overload of various types of motors, which influences the determination of the effective work and consequently also the cost price, nor various other matters. Nevertheless this calculation shows clearly how important it is for the correctness of such estimates that the figures relating to the various factors entering such estimate be sufficiently complete and reliable. It cannot be maintained that power economy is ensured by these data which we may consider as insufficiently defined, especially as regards their dependance upon the effective work, among others, wages, cost of lubri- cating and cleaning material; life of motors; expenses for fuel which arise through defective combustion from varions causes in the boiler furnaces and from short hours of work etc. Only data respecting the consumption of fuel per unit of effective work can really be considered as absolutely fixed. Naturally all these values are closely connected with the various factors: perfect construction of machines, local conditions, efficient workers, prices, etc. It must not be thought, however, that the result of exploiting numerous power stations, should it be possible to collect, such results, would give matter that would be difficult to compare or work out. General statistics have to deal with far more complicated organisms than Social organisms, with separate elements representing a still greater complication of influencing causes than human individuals. And yet general conclusions are quite possible; the law of gre at numbers may be applied in every study en m as se, and could be, with full justice, in the examination of statistical matter concerning central stations, if such matter were available in sufficient quantity. Unfortunately there is at present no world organisation that could respond to so comprehensive an investigation. There are both international and national organisations of refrigeration. The matter itself is new and not so highly developped as the mechanics of central power stations. It stands, at present, on the first step of its enor- mous future development. For this reason it appears to be a suitable time now to form an organ whose special work should be to collect and work out statistics from machine stations for artificial cooling. The possession of sufficient data on the application of the methods of economy in forming plans is doubtless of great importance, but it becomes still more important when it is remembered what an important rôle 277 refrigeration machines are destined for in the future as factors in a rational thermal economy. We may characterise this rôle by the following example: Let us take a town of about 200,000 inhabitants, having a slaughter-house and municipal artificial cooling stations. For a town of this size the latter might give 1,600,000 units of heat per hour. (Data of Kansas City.) The slaughter-house requires 500,000 units of heat per hour, for which about 300 HP would be necessary for compression machines, and from 150 to 200 HP for the power equipment proper of the slaughter-house. (Data of the slaugther-house at Offenbach a.M.) Suppose that the projected central station is to supply the municipal cooling stations and the slaughter- house with artificial cooling and also to provide energy for the power- establishment of the latter. If compression machines are used, the neces- sary motor power per hourly number of calories = 1,600,000 + 500,000 = 2,100,000, plus 200 HP for the mechanical establishment, - about 1.300 HP, or in round numbers, if the whole establishment be taken as electrical, about 1,000 KW. If steam turbines are used for mechanical driving power, the steam consumption will be expressed by 73 kg per KW hour, i.e., all together 7.300 kg per hour. Suppose the same central station be fitted with absorption machines. It may be taken that on an average, with 100,000 units of heat per hour, such a machine will use up 300 kg steam at 3 atm. pressures. The steam consumption in general will be expressed by: (1,100.000: 100,000) × 300 = 6.300 kg per hour (at 3 atm. pressures). If the central station is fitted with a steam turbine of 1,000 KW with intermediate steam, it will, while letting out 6.300 kg steam at 3 atm. pres- sures, use up 11.5 kg steam per KW hour, i. e., all together 11,500 kg per hour. (Data of the Allg. Elektr. Gesellschaft). There remain, after deducting 200 HP for the mechanical establish- ment of the slaughter-house, about (1300–200 = 1100 HP) oo 820 KW for obtaining the electrical energy; this energy can be applied for various purposes. The development of this energy by the more complete utilization of the steam as compared with the operation of the central station with compression machines to the following extent: 11,500–7.300 = 4.200 kg per hour, i. e., 5.1 kg per KW heur. Therefore as we have just seen, this expenditure amounts, under ordinary circumstances, with a non-combination plant, to 73 kg per KW hour, in other words, the economy attained in fuel shows: [(7.3–5.1): 73}}{100s 30%. The example just given may serve on the one hand as explanation of the extensive horizon which, simultaneously with the appearance of new factors — cooling machines — is opened up by the idea of rational thermal economy, and on the other hand as distinct proof of the necessity for suf- ficiently complete data on working expenses. 278 While builders give suitable guarantees with every machine, we have, as yet, no reliable data as to the life of the various machines, their actual consumption of lubricating oil and water, the expense for labor and for repairs; not to mention that the guarantee figures cover only the ordinary expenses per unit of power, whilst the additional expenses which depend upon various circum- stances may reach an added 30%. The data published in special literature on trials before purchase, etc., are too meagre to afford a basis as regards other requirements, and at the same time the consumption of oil and cooling water for example differs very greatly in machines working with sulphurous an- hydride and ammonia or in absorption and compression machines, and the calculations just given could only be considered as sufficiently well founded if they also contained the charges for depreciation interest and repairs, water, oil, etc. Data are necessary not only for various types but also for various capacities; all hitherto available data of this kind are only of a chance character. On the basis of the foregoing, the writer suggests that periodical inquiries be made concerning the various working data of a number of artificial cooling plants. To anticipate possible objections it must be stated that there is no reason to consider such enquiry as violating trade secrets. In the first place, it is not necessary, for instance, to know the exact cost of fuel consumed: it is sufficient to know the weight and heating value; similarly, it is not necessary to know the wages of individual machinists, but merely the cost generally for employees. Furthermore many plants belong to public bodies which have no reason for keeping secret any data regarding expenses. Finally, knowledge of industrial statistics proves that, so soon as individual names are not used in the gathering of data, every impulse to keep data secret vanishes. The proposed inquiry could be organised as follows. The inquiry form (specimen of which is appended) could be worked out at once by a special committee chosen by the section, confirmed by the Congress and sent to the national commissions. One year before each congress the committees could send these inquiry forms to central stations known to them, they could tabulate the answers received and, some months before the congress, forward them to the Central Bureau of the International Association of Refrigeration for final working out, for laying before the congress and printing in the reports, Data so obtained would form valuable material not only for the history of the development of this branch of industry, but also for every engineer who at present is compelled to be content with chance data. Technical science has attained to such high development as gives it a right to make inquiry into special economies and to take the initiative in collecting material and thereby further the accumulation of independent 279 statistics, which is the necessary foundation to every economic discipline. This will be another of those services which congresses of refrigeration have already rendered to technics and industry, and will continue to render. Specimen inquiry form for securing data from artificial cooling --- plants. Questions to which answers do not appear to be absolutely necessary are marked with an asterisk. 1. Name and object of the refrigerating plant. 2. Number of units of heat per hour taken up, at a temperature of from . . . to . . . " C. 3. Manner of cooling whether by expansion direct of the medium or by brine circulation. * 4. Type of the cooling machine (Compression or absorption) and of the medium (Ammonia, sulphurous acid, carbonic acid, methyl-chloride). 5. Number and power of motors in HP. 6. Effective power of motors (normal load) in HP. 7. Highest overload of motors (maximum load) in HP. 8. Type of power motors (steam engines, turbines, gas generators, Diesel motors). 9. Manner of transferring the mechanical energy to the cooling ma- chines (whether by direct coupled electric motors or by belt transmission. 10. Builders of the motors, boilers, gas generators, etc. (Factory.) 11. Builders of the cooling machines. (Factory.) 12. Manner of cooling the motors and cooling machines (whether by water from the water mains, spring water, or stream water; are cleaners provided, or are forecoolers employed?). 13. Area of machine house and rooms. 14. Number of working days per annum. 15. Number of hours work per day of the power machines. 16. If the arrangement of work in days be unequal, the total number of hours of work per annum. 17. Probable or known life of motors and cooling machines or yearly depreciation. * *18. Cost of the plant or of the separate parts, machine-house, motors and their auxiliaries cooling machines arrangements for such. 19. Average annual cost of repairs (expressed in the sum expended if number 18 is answered, or in "ſo of original cost): 280 a) of the machine house . . . . . . . . . . . 6) of the motors . . . . . . . . . . . . . . . . . c) of the cooling machines . . . . . . . . . . . º º d) of auxiliary parts (boilers, superheaters, condensers, etc.) Total . 20. Annual consumption of fuel: a) Quantity of coal, anthracite, Naphtha, or petroleum, etc. b) Heat value and evaporating effect of the fuel c) Source of the fuel . . . . . . . . . . . *d) Price of unit of weight of the fuel • * @ e e) In steam plants: boiler pressure . . . Manom. Atm. (kg/cm3). Temperature of cooling water . . . " C, of the feed water . . . . . 0 C, of the steam superheating . . . " C. - In combustion engines; temperature of the cooling water . . . " C. In absorption machines: Steam consumption per 100,000 units of heat per hour . . . . . kg. at steam pressure of . . . Manom, Atm. (kg/cm3). 21. Annual water consumption in cu. m. : a) of feed water for boiler . . . . . . . b) of cooling water, if possible, separately: I. for motors . . . . . . . © II. for cooling machines . . . . . . . . . e III. for the condensers of the cooling machines Total . *c) price of feed water per cu. m. . . . . . . º *d) price of cleaning per cu. m. water if such takes place *e) price of cooling water per cu. m. . . . 22. Annual consumption of lubricating materials: a) Weight per annum . . . . . if possible separately for: I. Motors | Cylinder oil Machine oil . . . . . e - e. Cylinder oil . . . II. Cooling machines | Machine oil . . - Total . b) Brand of the oil and name of firm : I. Cylinder oil . . . . . . © e II. Machine oil s & e ºs *c) Cost of unit of weight of the oil: I. Cylinder oil . . . . . . . . . . . . . . II. Machine oil . . . . . . . . . . . . . . 281 23. Annual consumption of cleaning material: a) by weight — per annum. *ē) price per unit. of weight. 24. Cost of employees per an Illiſſ] . a) Number of engineers, oilers and firemen. *3) Wages of same. *c) Total cost of labor. 25. Consumption of cooling agent and other supplies per annum for cooling machines. (Quantity or cost.) - 26. If results of tests before purchase or other tests are available, copy of same is requested, g 2 8 2 The Distribution of Electric Energy and the Application of Cold. By M. Jupport, Engineer of Arts and Manufactures, Toulouse, France. The distribution of electric energy permits the installation of motors of any power whatever at any point of the plant, suitably arranged. This facility, in addition to the special advantages of the electric motor, cleanliness, lightness, compactness, ease of starting and regulation, small generation of heat, etc., all serve to establish the fact that the electric motor should be a very powerful factor in the development of refrigeration. It is well known that the periods of greatest demand for power for refrigeration occur when those for electric lighting are minimum, and vice- versa; therefore, the favorable sequence of light and cold production tends to regulate the average annual output of electric generating stations, and consequently to reduce the nett cost price per Kilowatthour. º, This advantage is especially valuable for Hydro-Electric work, so- called X White Coal & works. --- * - It would, therefore, be profitable, for the economic prosperity of nu- merous regions supplied with electric power, to point out to the electricians the important field they will open to themselves by favouring the construc- tion of refrigerating plants of all kinds, and the benefit in reduced tariffs, they would derive from supporting such plants, as the refrigerating industries assure to electricians an extensive employment of their goods and appliances. I am therefore proposing to the Second International Cold Congress the following vote. That: *In every country the International Association of Refrigeration shall bring to the notice of Electrical institutions (Technical and Scientific) the great interest which the central electric stations have in favouring refri- gerating industries, and in applying special reduced tariffs to them. 283 Refrigeration in Sweden with Ice and Salt. By Lauritz Nilsson, Christiania, Sweden. The great services which modern art of refrigeration has rendered in the manipulation, conservation and transportation of articles of food are certainly too well known to require mention here. It is equally well known that it is chiefly the perfection of mechanical refrigeration technics (so-called artificial cooling) during late years that has given complete control over temperature, made the introduction of perfectly dry, fresh and suitable cold rooms possible and caused the great development of which this Congress affords brilliant testimony. This development, however, has also contributed to the fact that cooling with natural ice has remained considerably behind even in countries with a surplus of this natural refrigerant, but lacking means for replacing it, such as coal, oil, etc. and (not least in importance) the considerable capital necessary. It is therefore confined to small requirements which mechanical cooling owing to its technic cannot satisfy , e. g. house-holds dairies and railway cars. It cannot be denied that this mechanical development acts against the laws of a good economy in such countries among which Sweden occupies the foremost place. We prefer to employ primitive methods and make use of home products even if imported means give superior results. The consequence is that in our country — as the refrigeration eugineer would say — we have remained behind. It is also selfevident that these natural hypotheses have resulted in great efforts to perfect ice-cooling that competition with other refrigerating methods may be carried on in countries having natural ice. I will therefore give a short account here of the results of these endeavours. I pass over all those arrangements and methods by which rooms are cooled through bringing the air into direct contact with ice. The results attained by these methods are bad in many respects and have prevented direct ice-cooling from being much used. Irrespective of many disadvantages, however, it is used to a very great extent in dairies, and particularly by the 2Alnarp & dairy instiute it is most ardently supported. 284 Mechanical refrigeration has demonstrated that cold rooms can only be satisfactorily maintained by cooling dry surfaces, and it is desirable to employ similar methods that owe their superiority to this. - .. To obtain good results by ice-cooling it is therefore necessary to make a uniformly cooled brine and circulate it in a similar cooling system. This was at first effected by pumping the thaw-water from a freezing mixture of ice and salt through a cooling arrangment and then again over the freezing mixture. The result was too unreliable to admit of its use for the cooling of rooms. Part of the salt mixture was never so much cooled as it might have been with its salt content and the freezing point fixed thereby, and the salt content fluctuated greatly bacause of the added RTning a torus ril L rºstirrisTaos nool-rroRSALJningsnrºticpoung. /Ozz. 72 O z 2 37 2 3- 6' Fig. 1. water. One began, therefore, to prepare the salt mixture in a special apparatus and thereby to determine the freezing point, and in another apparatus, by sufficiently fine separation and thorough stirring with the ice, to reduce its temperature as much as its salt content permitted, practically to about 1° above its freezing point. We know that the temperature of a salt mixture sinks about */,” for each percent of salt, and as, in the specially constructed apparatus, the percentage content of the salt mixture, whose temperature is reduced to the lowest limit, can be regulated at will during working, we have found simple means of exercising the desired control over the temperature of a cool room through a refrigerant whose tempera- ture can easily be reduced to 18° C. and kept constant. - 285 zo Zzzzzzzzzzzzzz•ZEZ Pºzzzzzzz| 2^ ~zºze7×)& G-Z-Z-Z。、「·º ：227~*~3,2*2.a.， § 92^322 •ş~#3 Z. Z. … Tº}}75 cººeſº！??-93 Żae -<！= :::：:：：::：*ae <！--- ſ . . Üf L - - - -] : \º-ºº- . . 48}- ~ ~ ~ */º.ſ.9}}#-| .*ğĚLITT, 75řEËIII）, ſ į {# * . ：:* ~~~~）;2， º =Zºzº [ …»， ·/p/ț| ~^277>2 ||“?· }| . ' ∞ = l---- -J; ;|-------!---]; §§-}.4%- }}w·Jē4--+---------• • •ł•£ 1 - - -~ • + • ~ ~~~~ ~~~~ ~4%， vraea， 1 ! * --·+ |-§ . . -----， ezzº • ·|| | | | { • ~~ ~~ i-å 286 On the other hand we can work solely with such salt addition as is best for the prevailing conditions which can always be calculated. To this arrangement the name * Frigators has been given. * By such an arrangement the ice is made to more rapidly absorb heat and this condition is made use of in a manner that satisfies the highest demands. Wherever this system has been introduced during its short existence the results have been very satisfactory. I submit a diagram of a refrigerating magazine for storing eggs. The arrangement works, as is evident, only for half an hour every morning, and consequently requires the least imaginable attendance. To make this possible, i. e. the slight attendance, the refrigerating system consists of cylinders which hold 75 litres of refrigerant per sq. metre and thus store up a quantity of it. In very hot weather a 10°ſo salt solu- tion was used whose salt content was gradually reduced to about 4–5°/o according to the fall of the outside temperature. The relative moisture con- tent was between 80 and 90 per cent. The eggs keep perfectly. To refrigeration Engineers who have had an opportunity of seeing these arrangements at work, it is clear that from a technical point of view there' is now nothing to hinder the most extensive application of ice-cooling. Consequently it is of the greatest interest now to consider the economical factors also. & Concerning the low cost of the installation there is no doubt. For the refrigerating system the costs are the same whether ice-cooling or mechanical cooling be used. The cost of the generator System for ice-cooling are however but a fraction of those for mechanical cooling. Above all, working expenses are dependent upon the conditions of the ice, and some explanations on these matters may be of interest. . For storing the ice, so-called ice-houses are made use of. The loss through thawing is estimated at maximum of 50 Kg. per sq. metre outer surface per annum. For cutting the ice ice-ploughs, or still better, motor saws are used, which cut the ice into uniformly shaped pieces. Elevators are employed for transporting the ice to the houses. If the ice-house is near to the ice-source then the costs for the application of the ice, with a consump- tion of 20,000 tons, are as follows: Sawing and cutting up of 22.000 tons . . . . . . . . . . . K 4.400"— 10°/, interest and amortisation for ice-house and other arrange- ments (max. K 100,000–) . . . . . . . . . . . . . . * 10,000— Rent for site, and other expenses . . . . . . . . . . . . . . 2,000"— K 16.000"— or about 80 &re per ton or 1 &re per 1000 W. E. = 3.96 B. t. u. If the source of the ice is some distance from the place of application the cost of transport must, of course, be added to above calculation. For smaller requirements and without labor saving machinery the expenses naturally run somewhat higher. 2. 287 The salt serves to regulate the temperature, and the amount consumed . depends upon the temperature desired. In general the arrangement is so made that — solutions with more than 100/0 salt are not used until the temperature has to be kept below zero. If it is desired to obtain different temperatures in different rooms then the solution from the coldest rooms is used to concentrate the Solution in the other rooms, great saving being thus effected; and it is only necessary to reckon with this low percentage of salt for the whole amount of ice consumed. The average price of the salt is 10 Kronen per ton. If we therefore work with as much as 10°/o salt content the cost will be about 2 öre per 1000 W. E. or 1 &re for 5%. The total cost for refrigerant for 1000 W. E. units of heat amounts therefore to about 2–3 Öre, a rational result scarcely to be attained by another method even with very economical and extensive equipments. A special adaptation of this arrangement is used for cooling railway cars. Last summer two such cars were subjected to thorough Com- parative tests by the Royal Swedish State Rivijs. They showed its absolute superiority over other systems, and the railway ordered a number of such cars and purchased the right to build such cars in future. It is now practically demonstrated that in these new arrangements we have a unique system which with the use of our own natural product satisfies the demands made. - It now only remains for us to mention what is by no means the least important question, namely, how the best advantage may be drawn from this situation. Mechanical refrigeration arrangements require comparatively large plants for satisfactory results. The smaller the plant, the dearer the cooling effect per h. p., the greater the comparative cost of plant and the less the pro- bability of expert management, and consequently the less is the certainty of regular working. The natural consequence is that — to attain a rational working result — it is necessary to collect goods together in great quantities. Similarly it follows that large cold stores, large abattoirs to which cattle must be brought alive from great distances, and large magazines at the point of consumption must be erected, in which great quantities of goods must be collected from all directions. The tendeney is in fact to the concentration of refrigeration, and it is reserved almost entirely to large industries or capitalists to derive advantages therefrom. * Knowing the necesity for refrigeration, we know that present conditions are not in agreement therewith. The shipment of living animals depreciates the quality of the meat and is also dearer and more risky than a duly regulated meat transport. Eggs, days or weeks old and already 288 damaged on this account, are naturally sacrificed when placed in the cold store, whatever treatment they be subjected to. e Fresh picked fruit when refrigerated doubtless keeps much better than that which is some days old. Milk can only be refrigerated to advan- tage in the dairy immediately after milking. Fish, fowl, and game must be refrigerated immediately after obtention, and this is the primary consideration in all cold magazines. - It is therefore evident that there are two opposing factors, and practi- cal requirements must naturally follow technical possibilities. It is clear indeed that science has effected many changes in this respect. The above mentioned rational working is not solely reserved for large plants but is, with these practical arrangements, ensured for the smallest plants, indeed, even for the household. The cooling effect of 1 Kilo ice is the same everywhere, and only the cost of distribution is higher for small plants. Ice may be more easily obtained at the various points of production than at the points of great consumption, and the manipulation of the apparatus is so simple that it is scarcely necessary to explain it. Goods thus can be placed under refrigeration in perfectly sound condition, after which they may be successfully carried for long periods. By proper refrigerated transportation perishable goods may be success- fully conveyed from the producer to the wholesale and retail dealer, even to the household. Thus the great advantages of cooling are not reserved for capitalists and large industries, but are also rendered available for people of small means. Large cold stores may be entirely left out of consideration, and the cooling should be effected at the place of production, where several smaller refrigerators should be built to promptly recieve and store all products: eggs, butter, poultry and fruits from the farm, as well fish at the harbors. All goods to remain in these stores until they can be sold at good prices. They are later transported to the inland or foreign place of con- sumption in refrigerator cars which can be maintained at suitable tem- perature and dryness, they are again placed in cold stores until the time for distribution arrives. This is completed by proper refrigeration in the shops, restaurants, dairies and the household. This is the programme at present in vogue and which is everywhere accepted with interest. A central association is being formed at Stockholm to undertake this business work. The managers of the Royal Railway Co. made a beginning by ordering the refrigerator cars; they guarantee that there shall be no want of refrigerator cars and declare, also, that they will support the cold storage warehouses in every way possible. A special company is being organised for the traffic on private railways. - The Home Secretary has also promised his support and shown his interest in many ways. 289 In agricultural Societies, state offices and wherever these matters have been dealt with general interest has been exhibited. Some dairy companies have already taken the matter up, and among those who deal largely in fish, fruit and eggs the decision to participate is evident. In several towns ice companies are being formed to undertake the business of fitting up and hiring out ice-safes, the arrangement of cold plants and the sale of ice at moderate prices. If the present rate of progress continues our country will, before the next Cold Congress meets, have an organisation of her own which will be of the greatest benefit to food products and their sale. I hope that there will then be no complaint as to the quality of our crown berries, that our butter will always arrive in good condition, that our periodical Surplus of fish will be sold on the markets of central Europe, that the greatly varying prices of food will be adjusted in our extensive country which suffers from a surplus in the south and dearth in the north, and that the great losses through waste will cease. The Frigator refrigeration wagon has shown its ability to extend the disposition of goods by the manner in which it has effected the transport of fresh fish from Drontheim to Berlin, from Narvik to Vienna, and four days' transport of fresh killed meat from the south to the north of Sweden. The small magazines have already shown and will still further show their equal ability to extend the market temporally. As it may be of interest I will describe such a magazine of the smallest dimensions, namely, 50 sq. metres available floor surface. It contains both ice and provision divisions, the latter divided into four rooms which can be independently cooled to various temperatures and accordingly accommodate different classes of goods. These magazines are, naturally, made in every desirable size and placed near dairies, factories for preserves or, for preference, near railway stations. Such a refrigerating magazine with ice house and 100 sq. metres floor surface costs about 11,000 Kronen and contains about 150 tons of ice, which cost an equal number of Kronen, and 200 Kronen for salt, so that the cost amounts to about 350 Kr. per sq. metre. With proper use of 150 Kronen of salt one could profit 50,000 Kronen in such a magazine filled with 50,000 score eggs which fluctuate at least 1 Kr. per score with us. From this, therefore, the greatest advantage accrues to hundreds of people, producers and consumers, middle-men, etc. 19 291 Report of Proceedings of Commission II. 1* Sitting, 6* October, 1910. The Sitting began at 2 p. m. and ended at 4:45 p. m. Honorary President: Dr. Hans Lorenz (Germany); President: k. k. Oberbaurat Dr. Camill Ludwik (Austria); Vice-Presidents: Prof. Ing. Hugo Seidler and Dr. Richard Jahn (Austria); Secretary: Ing. Richard Kurss a (Austria.) * The President Dr. Ludwik (Austria) opened the sitting with the following address: - - -- Gentlemen, The time afforded to Commission II for the discussion of the large quantity of matter is very limited in consideration of the arrange- ment of the Congress. I will therefore be short and concise even in my welcome to you, but desire in no way thereby to detract from the warmth and heartiness of this welcome. I feel justified by the programme of the Commission in the confident hope that the discussions will bear good fruit. Permit me, before I proceed to the first item in the day's programme, to describe shortly the way in which I think the business should be conducted. . In the first place I must request you to be as concise as possible, in consideration of the short time available. Please, note further that we intend to translate all French and English papers into German immediately with the aid of our interpreters, but that the German papers will only be given in full in English and French if the gentlemen desire it. Finally it is evident that our discussions can only be of an informative character, for definitive conclusions can only be drawn up by the general meeting of the Congress, before which we lay our decisions. $ If no one has anything to say with regard to my suggestions I regard them as accepted. (Agreement.) We proceed to the election of Honorary Presidents. Prof. Seidler will inform you of the names proposed, the interpreter will interpret them. Prof. Hugo, Seidler (Austria): In the name of the management of the Commission I beg to propose the following gentlemen as Honorary Presidents: * - - - - - - 19% 292 Prince Roland B on a part e (France); Staatsrat Basilius v. Denniss off (Russia); Geheimer Hofrat Prof. Dr. C. v. Lin d e (Germany); Prof. Dr. Hans Lorenz (Germany); Director I. de Saugy (England); Generalintendant Maur in (France); A. Barrier, engineer at the war office (France); Beau més, Chief engineer of the fleet (France); J. F. H. Koopmann, Maschineningenieur, Privatdozent for Refrigeration technics at the university of Delft (Holland); Ing. José Mattos Braam camp (Portugal); Prof. Knut Ljung man (Sweden); Dr. Ludwig Ballai, kgl. ung. Hofrat in the Patent Office (Hungary); Stephan Röck, Maschinenfabrikant (Hungary); Gabriel Holle rung, Maschineningenieur (Hungary). Dr. Camill Ludwik (Austria): If no objection is raised I take it that the gentlemen named are chosen as Honorary Presidents. - As we think it most important that the Honorary Presidents should be so kind as to conduct the proceeding of the Commission, I beg Prof. Lorenz to accept the presidency of to-day's sitting. I am delighted to be able to leave the Chair in the hands of a technicist so eminent in the province of the Refrigeration Industry. Prof. Dr. Hans Lorenz (Danzig) takes the Chair amid loud cheers: In thanking you for the honour you have done me, I beg those Honorary Presidents who are present to take their seats at the president's table. Kindly permit that we immediately enter upon the programme for the day. I call on Mr. N. Boro dine for his paper on 2 T he present state of the Refrige ration Industry in Russia.<. Staatsrat N. Borodine (Russia) speaks in French. (See p. 267.) . President: Do the gentlemen desire that the paper be interpreted in German and English This not being the case I open the discussion. Does anyone desire to speak? This seems not to be the case. I thank the lecturer. > - I call on Prof. Satke witsch for his paper on 'What is to be unders to od by the economical degree of efficiency of a refrige rating machine P& - Prof. Alex. Satkewitsch (Russia) gives his paper in French (See p. 77.) President: Is interpretation of the paper desired This not being the case I open the discussion. * Ing. Fritz Krauss (Austria): The proposal of Prof. Satke witsch seems to me to be so important and valuable that it should not pass without discussion. It proves in so far to be entirely consequent and rational 293 in as much as the working process of the refrigerating machine should be judged in the same manner as is that of the steam engine. The degree of efficiency of a perfect steam engine is expressed, as is well known, by the proportion of the surfaces A -- O in the heat diagram, where the surface A is the heat value of the work done by the perfect engine, and Q is the quantity of heat led off in the condenser. If, therefore, n = is the A * - - - A + Q degree of efficiency of the steam engine, in which the important point is the obtention of the mechanical work A, then, in a consequential manner, the degree of efficiency of a refrigerating machine with which it is required * º g º A to obtain a cold production Q will be n = A + Q’ heat value of the work of the compressor expended in the production of the refrigeration effect Q. The heat diagram holds good for both processes. It would be interesting to learn whether there exist any objections to the proposal of the lecturer. I can think of none at the moment. President: I would like to say that the proposal is indeed entirely consequent like that for the steam engine. The objection that the tempe- rature is not contained in this circle of efficiency falls to the ground, because it is not considered in steam engines either. It is a proposal thoroughly worthy of our consideration. Further, reference has been made to such a thermal circle with variable upper and lower temperatures in the refrigerating engine. The lecturer proposes a middle thermal circular process. In my dissertation for the doctorship I described this as polytropical thermal circle, and our senior master Zeuner made use of this term in his book, mentioning my name. You will find it also in my technical heat primer, how the variable nature of the temperature above and below may be expressed in the circle of efficiency. where A gives the *. I thank the lecturer for his interesting statements and call on engineer R a utenkranz for his paper. Ing. J. Rautenkranz (Austria) gives his paper on > Electrical distance the rm o meters<. (See p. 84.) President: Is interpretation desired It is not. I open the discussion. Ing. A. Barrier (France): Have Messrs. Siemens also arranged their apparatus in such a way that the temperature of the inner parts of the meat can be taken during the freezing process ; Ing. J. Rautenkranz (Austria): The electrical distance thermometers of Mssrs. Sienaps and Halske are also made use of in the medical profession, namely, for electrical registration of fever. An apparatus is used similar to that put up here, only the resisting elements are enclosed in very small gold cases. - The instrument makes it possible to measure the changes in the temperature of the blood for a certain period of time. 294 These instruments have not been used as yet in the sense, mentioned by the previous speaker, yet there is nothing to prevent this method of measurement being applied for this purpose also. President: I call on Obering. Adolf Tegetmeyer for his paper. Obering. A. Tegetmeyer (Germany): On 2 Experiments on dry and wet condensing processes of the Con densing Refrigerating Machine. Advantages and disadvantages of these systems<. (See p. 106.) • & -- y President. The paper is printed in English also. Is a resumé in French desired? (Voices: No!) It is not the case. I open the discussion. - Prof. Dr. Oskar Knoblauch (Germany): The statement of the lecturer to the effect that it is not difficult to separate the damp by means of a separator from moist ammonia vapour agrees with experiments that have been made on steam in the laboratory for technical physics at Munich. According to these, the principal part of the moisture flows trough conduits to the bottom of the conduits and only very slight traces of it remain suspended in the steam space, in the form of little drops. These cannot be separated even with the most finely constructed water separators. This explains why the lecturer found no difficulty in extracting the moisture. An eccentric sheave might be put in which would form a dam for the moisture, then the steam passes through and the sheave catches the moisture; that is a convenient means. - Obering. A. Tegetmeyer (Germany): The separators must not be taken too small, because they must catch also the larger quantities of moisture, which, from time to time, come from the vaporisers, in order to avoid deposits of moisture in the condenser. \ . President: As no one else desires to speak I declare the discussion closed and thank the lecturer. I call on Obering. Banfield for his paper. Obering. R. Banfield (Germany) renders his paper on >The manu- facture of crystal ice from s team and results atta in ed in practices. (See p. 135.) *. - President: I open the discussion. Obering. Adam Weinberger (Austria): I should like to ask how it was possible to eliminate the unpleasant taste possessed by ice manufactured from distilled water? (Blasengeruch, bubble smell.) * - Obering. R. Banfield (Germany): This question really does not apply to-day, for complaints respecting the abnormal taste of crystal ice are not met with any more. It is probable that, at the low temperature of the distillers, when connected with the exhaust conduits, certain decomposition processes in slightly impure drinking water, which may have occurred in the former high temperature distillers, no longer take place. ſº The question being put to the meeting no one was able to testify to the presence of >Blasengeruché in crystal ice. -- - * President: I thank the lecturer and close the discussion. 295 Mr. Kolischer will be so kind as to read the paper by Mr. Thomas Shipley on 2 Experiments on the efficiency of ammonia com- pressors with dry and wet process, and on the efficacy of ammonia condensers after dry and wet systems. (See p. 91) President: I thank Mr. Kolischer for taking the trouble to read to us this interesting paper. As no one notifies a desire for discussion, I close to-day's sitting and adjourn the conference till to-morrow morning at 10 a. m. To-morrow we shall have the pleasure to greet Mr. Barrier as president. 2* Sitting, 7” October, 1910 The sitting began at 10:45 a. m. and lasted until 12:30 p.m. Honorary President: Ing. Albert Barrier (France); President: k.k. Ober- baurat Dr. Camill Ludwik (Austria); Vice-Presidents: Prof. Hugo Seidler and Dr. Richard Jahn (Austria); Secretary: Ing. Richard Kurssa (Austria). Chairman: I open the sitting and call on Prof. Dr. Lorenz for his paper on "The possibility of making use of turbo-blowers as c on dense rs in refriger a ting mach in e s - (See p. 128.) Prof. Dr. Hans Lorenz (Germany) gives his paper and then continues: Gentlemen, It seems, perhaps, somewhat venturesome for me to speak on refrigeration technics here, after having discontinued the study of this sub- ject for the last six or seven years. In my other studies a matter has come to my notice which I believe would be of interest to some of those here. I will say further that such blowers as are here explained have already been built and have proved to be most advantageous. (Cheers.) Géza v. Krenczey (Hungary): What factory has made them? Prof. Dr. Hans Lorenz (Germany): They are built in a Nürnberg factory, in the first place for air. Their application for refrigerating machines is for the future. The gentlemen will in fact have to decide as to whether they are to be represented as being suitable for the purpose or not. I see no reason, however, why this should not be possible, if it is possible for air. * Géza v. Krenczey (Hungary): It is claimed for the turbo-compressor that with an effective 200 h. p. it can produce 500,000 calories. Comparing this with the ammonia piston compressors which with super heating give up to 3400 calories as the result of an effective 1 h. p. there would be an efficiency so very much smaller that the possibility of employing turbo- compressors would become questionable. May I ask for an explanation in this respect? Prof. Dr. Hans Lorenz (Germany): The datum 200 h. p. cannot be taken as a standard either for the expenditure of work or for the guarantee, but merely for the greatest power of the driving engine, taking into con- sideration the possibility of overcharge. 296 Geheimer Hofrat Dr. C. v. Linde (Germany): What results have been attained with the turbo-compressor in the case of air? Prof. Dr. Hans Lorenz (Germany): In this respect I can state that we have measured for air 76°/o the amount of work necessary for the adiabatic compression on the table of statistics. In this figure all losses, losses through leakage, etc. have been taken into account. Geheimer Hofrat Dr. C. v. Linde (Germany): The question seems to me to be settled by the fact that such a turbo-compressor must possess an efficiency at least equal to that of a piston compressor, because there are a whole Series of advantages, which are mentioned in the paper, in favour Of the former. Obering. Adam Weinberger (Austria): It may be seen from the table of statistics contained in the paper that it would hardly be possible to execute these turbo-compressors with an efficiency of over 500,000 calories with media other than sulphurous acid. May I ask the Professor for his opinion as to whether it may in the future, perhaps, be possible to overcome these difficulties with other media than sulphurous acid, such as ammonia, carbonic acid. Prof. Dr. Hans Lorenz (Germany); I do not know that. Obering. Adam Weinberger (Austria): If the absolute pressure be taken at 0°, enormous volumes are arrived at. Perhaps there may yet exist the possibility of overcoming the difficulty with compound effects. * Prof. Dr. Hans Lorenz (Germany): For bodies other than sulphurous acids the only consideration that could exist would be a combination of the turbine wheel with other arrangements, for example jet blowers, in the manner of the Le Blanc-Westinghouse machine. There are certain difficulties in the way of this, however, for that is no pure compression engine which in the first place maintains the vacuum. I am convinced that with the blast not removed at this low tension one must be reduced to the vacuum, at all events it has not yet been achieved. O Obering. Adam Weinberger (Austria): Perhaps it could be effected by means of condensation. Prof. Dr. Hans Lorenz (Germany): Then we should not have a pure compressing engine. Obering. Adam Weinberger (Austria): The Le Blanc engine is attracting much notice at present. I should like to have the connection between the turbo-compressor and the Le Blanc engine defined. Geh. Marine-Baurat Köhn v. Jaski (Germany) recommends care in the choice of makers of high pressure turbine pumps, as the avoidance of kicks, at all events with water, seems to depend upon the proper construction of the wheels. In practice, moreover, there may also be a certain unreliability as regards the coefficients. I desired only to mention this experience because it might perhaps be of interest to some of the gentlemen. (Voice: Can you name a factory?) I heard from Herr Professor that only one factory in Bavaria builds such pumps successfully, - 297 Prof. Dr. Hans Lorenz (Germany): For air. Such are now much built for Germany. Then there is a factory at Nancy which has delivered a quantity of such pumps for the French navy, for air and for water. These have turned out very successful. - 2. Ing. Fritz Kraus (Austria): Referring to the remarks of the previous speaker, I beg to say that the turbine pumps are used with great success as boiler feed pumps and that no complaint has arisen at works that make use of a steam pressure in the boilers of from 10 to 15 atm. Chairman: I think that I may speak in the name of all the gentlemen when I thank Prof. Dr. Lorenz for his interesting remarks. They deal with an improvement well worthy of attention, namely the application of the turbine principle to the production of cold, and it will be interesting to watch the further development and practical accomplishment, concerning which I hope that Prof. Dr. L or en z will report at the next Congress. Ing. Heinrich Ottmann (Germany) gives the paper on 2 Art Pu m ice and its a pp lic a ti on as a n in su la ting m a terial.< (See p. 245.) Chairman: I would like to know the coefficients of the conduction of heat for mixtures of art pumice and cement, for various proportions of admixture and thicknesses of the layers. Ing. Heinrich Ottmann (Germany):. A loose filling of insulating material, by means of pouring in art pumice or art pumice filling, has a coefficient of conduction of heat of '095, while art pumice insulation concrete (mixed in the proportion of 1 part of Portland cement to 8 parts art pumice) has a coefficient of conduction of heat = 19.”) It is possible to execute buildings directly in art pumice, because it has the necessary solidity. Chairman: Must then less art pumice be taken and more cement, or the reverse? Ing. Heinrich Ottmann (Germany): The coefficient of conduction of heat varies according to the proportion of Portland cement and art pumice. With a larger proportion of Portland cement the coefficient of conduction of heat of art pumice concrete is lowered, with a smaller proportion it is improved, yet only by about one hundredth part. If it is of importance to construct very light buildings, which shall have great strength of compression, we should take more cement, but if it is required to improve the insulation value we should take less cement. Chairman: Could you perhaps give examples? Ing. Heinrich Ottmann (Germany): For example: I arranged myself the refrigeration plant at the slaughter house in Munich, and also that of Several breweries. These are carried out in concrete and partly with art pumice filling. *) Attest: Laboratory for technical physics of the k. techn. Hochschule in Munich, Prof. Dr. K no b l a u c h. 298 Prof. Hugo Seidler (Austria): Is it possible to give details of the proportions of admixture made use of in these cases? r Ing. Heinrich Ottmann (Germany): The proportion of admixture is generally from 1:8 till 1:6. On the basis of experiments we may take 065 as the coefficient of conduction of heat for cork stone. That is the number, if I am not mistaken, which this form of cork stone from Mssrs. Grünzweig and Hartmann shows. Art pumice filling has 095. That is a proportion of about 2:3. I at all events have always used it thus and have never failed with it. Thus one can replace a 10 cm. thick layer of cork stone with 15 cms, of art pumice filling. - Géza v. Krenczey (Hungary): How do the prices run? - Ing. Heinrich Ottmann (Germany): In Munich a cubic metre of art pumice filling costs 12 marks. For a filling of 20 cm. thickness we get the fifth part per square metre, that is 2.40 marks, and with this one can replace a 14 cm. thick cork plate. 2. I have also mentioned that it is ſpossible to manufacture art pumice. out of by-products. It is then a matter of suitably refining these. That is a question that has still to be solved. Ing. Lazarus (Fiume): Is it possible to make art pumice in such a manner that it, in a form something like mortar, can be used for heat insulation on conduits and boilers? Ing. Heinrich Ottmann (Germany): In this direction we have, indeed, already made experiments; we have also combined art pumice with magnesium, but this does not pay. I have for the most part limited myself to building construction, and I say openly, that only there have I found exceptionally great advantages. t *- ing. Lazarus (Fiume): It is yet possible, however, to make use of this material for insulating steam conduits and boilers? Ing. Heinrich Ottmann (Germany): It is possible to make the material somewhat coarser. But I have never yet been led to make any such trial. We have only insulated buildings, and we have found a rich field of work in this direction. - Chairman: I thank the lecturer for his paper, which deals with a very interesting subject. I beg to inform the gentlemen present that Mr. F. E. Math cw s (United States of America) has submitted a paper on 2 Improve ments in the c on struction of refriger a ting machine S. Results of experim en ts. & Mr. M at he ws is not present. The paper, which has been printed, will not be read on account of its length. (See p. 145.) Mr. Rushton reads the paper, written in English, by Mr. van Rensselaer H. Green, United States of America, on > New and improved methods of making Ice. (See p. 260) Chairman: I call on Mr. Bi quard for his paper. 299 R. Biquard (France) gives his paper on >The efficiency of various he at insul at in g materials in cold stor age room s. Experiments on the he at c on du citing cap abilities.< (See p. 206.) Charles Pasquay (Germany). By whom were the coefficients of radiation mentioned by you determined? They do not agree with those given by Mr. Pe c 1 et. Mr. Biquard (France): These are only approximate values, but they are in agreement with the values of the tables which are in general use in France for the calculation of heating plants. - W. D. A. Bost (England): With regard to the differences in the super- ficial heat measurements have you been able to observe any regularity for various thicknesses of the layers? - R. Biquard (France): Just these details I have not studied sufficiently closely, that is, I have not determined the relative figures, in order to be able to fix a rule respecting the influence of the thickness of the gaseous layer. It may be taken for granted, however, that commencing at 1 m the transmission of heat is independent of the thickness of the gas layer, and that in consequence of the convection which occurs in most cases. An exception must be made, however, for the case in which the insulating wall is situated horizontally and is colder than the layer of air over it, when the convection would probably take place to a very slight extent. W. D. A. Bost (England): Have you tabulated the results obtained with various materials? Do the coefficients given by you appear independent of the temperature? --- R. Biquard (France): So far I have only experimented on insulating materials, of which cork formed the base material. The coefficient of the conduction of heat of these materials increases by about */150 of its value for every degree of increase in the medium temperature. W. D. A. Bost (England): Could-you demonstrate a noteworthy in- fluence of the arrangement of the lamellae. R. Biquard (France): I have demonstrated by means of experiments on different hollow bodies (bricks, concrete etc.) that the arrangement of the lamellae of the insulating material is indeed of considerable importance. In practice it is very difficult, of course, to avoid the drawback that the air cells get filled with moisture, whereby their efficiency is greatly reduced. This is confirmed by builders of refrigeration plants. W. D. A. Bost (England): I do not understand how it is that in your experimental apparatus the ice could be kept from melting, when the apparatus was placed in a vertical position or if the ice was beneath the apparatus? R. Biquard (France): A metal net in connection with strong springs is provided by which the ice is kept in close contact with the upper wall, if the apparatus is laid on its side or turned right over. Prof. Dr. Oskar Knoblauch (Germany); I would like to add to the lecture the following remark. This dependence of the capability of con- 300 duction upon the temperature has also been determined for temperatures below zero. Experiments have been made in this respect at the technical- physical institute in Munich, and these experiments were described in the paper of the Society of German Engineers. These experiments showed that, the heat conductivity increases for temperatures below 0°, just as it has been proved to do for temperatures above 09. In the determination of the capability of heat conduction we descended to the temperature of liquid air. And here the observation was made that the lower the temperature is, the slighter is the heat conductivity, so that it may be said in general: If the conductivity of an insulating material has been fixed for a given tem- perature of the material, and the material is to be applied for insulating purposes at temperatures below 0°, success is so much the more certain if the coefficients of conduction of heat are also determined for a lower tem- perature. In this respect the material will get better and better as the tem- perature decreases. R. Biquard (France). With regard to this point I have very often referred to the work carried out by Prof. Knoblauch's colleagues, and especially to those of Mssrs. Nüsselt and Gröber, which showed that within the limits within which it was possible for them to experiment (namely from — 190° C. to 600° C.) the coefficient of conduction of heat increases with the temperature. The relative figures which I have quoted for the cork agglomerate also exhibit this regular increase, which amounts, as already Stated, to about 1/150 per 1" increase in the medium temperature. Chairman: We thank Mr. Biquard for having had the kindness to carry out a series of experiments on insulation materials in the sense of the resolutions of the Ist International Congress of Refrigeration. The results obtained are very interesting. The discussion shows that there are still many important points that require to be studied, particularly the influence of low temperatures on the coefficients of conduction, namely temperatures between — 20° and — 259, which are maintained in some cold storages for the purpose of freezing the meat. It is desirable that we request Mr. Biquard to continue his studies and experiments in respect of the temperatures mentioned. As none of the other gentlemen are present, whose names are down to read papers, I declare to-day's sitting closed and state that Geheimrat v. Linde will do us the honour to take the Chair to-morrow. 3* Sitting, 8* October, 1910. The Sitting began at 10:05 a. m. and ended at 1:30 p. m. Honorary Presidents: Geheimer Hofrat Dr. C. v. Linde (Germany) and Mr. Gardner T. Voorhees (United States of America); President; k.k. Oberbaurat Dr. Camill Ludwik (Austria); Vice-Presidents: Prof. Hugo 301 Seidler and Dr. Richard Jahn (Austria); Secretary: Ing. Richard Kurssa (Austria). * Chairman, Geheimer Hofrat Dr. C. v. Linde (Germany): I open the sitting and call on the President Dr. Ludwik. K. k. Oberbaurat Dr. Camill Ludwik (Austria). When we had the honour to propose honorary Presidents to you for this Commission, we naturally desired to remember the gentlemen from America. At that time, however, no candidate was nominated for us to elect. I have the honour to make the proposal to you to-day to elect as Honorary Presiden Mr. Voorhees who is present with us in the meeting. (Loud applause.) Chairman: I beg Mr. Voorhees then to take place beside me. I call on Prof. Dr. Ritter v. Smolu chow ski for his paper on 27 he Conduction of he at of bodies in the form of powder and a process of he at insulation founded the re ons. Prof. Dr. Maryan Ritter v. Smoluchowski (Austria): I have to speak to-day about researches that I have carried out solely for theoretical physical interest, but which probably also admit of several practical appli- cations. (See p. 187). Chairman: An epitome of the paper is desired in English. Prof. Dr. M. Ritter v. Smoluchowski (Austria) repeats his paper in the English language. Prof. Dr. Oskar Knoblauch (Germany): I do not wish to anticipate the appreciation of the paper on the part of the Chairman, but yet I feel I must give expression to my special pleasure at hearing that on a free scientific basis a progress has been made that may be of interest to technical men. I would now like to ask the speaker whether he has already made experiments on a larger scale such as is used technically, or whether he has the intention to make such experiments. If he would not do so I should be willing and also in a position to institute such experiments. There would be no great difficulty in the way of carrying out these experiments in a Val CUIUlſſl. - Prof. Dr. M. Ritter v. Smoluchovski (Austria): I beg leave to say that I have instituted experiments on the applicability of such powders for insulation in the Dewar vessel. I should be very pleased, however, if other gentlemen would also devote themselves to these things. I think, however, that the method which Nusselt made use of would be rather difficult of application here, for Nusselt requires a very long time to wait for the stationary condition. I think that in the case of cork powder he waited a whole week. We have to do here with a power of heat conduction which is twenty times smaller than that of cork powder. As I made several hundred experiments it was impossible to follow Nusselt's method. Chairman: Does any other gentleman desire to speak? If this is not the case 1 should like to express the great pleasure that it has certainly been to all of us to learn that the question of the capacity for conduction of heat has been transferred from its state of pure empirical examination of proportions, with which doubtless very many factors are connected, into the state of the physical scientific examination of all individual processes, so that the natural relation of all sizes that come here into consideration are examined and determined. There arises from this a much safer basis for future experimental research, which also renders very much work unnecessary that would absolutely have to be performed but for this basis. I think that we must be especially grateful to the lecturer for having directed us in this way. (Great applause and clapping of hands.) Chairman: I now call on Ing. Max Grün zweig for his paper on » C or k as a he at in Sul at Org. - Ing. Max Grünzweig (Germany) gives his paper. (See p. 221.) Val. Allent Noodt (Germany): Permit me to draw attention to some errors which are contained in the table. These have not crept in through any fault of the lecturer but they are evidently printing mistakes which are already in the printed copies of Dr. Nusselt’s paper. It is said here that the lamellar carbon has a filling density of 215. That is not correct, it is 134, and in the compression usual in refrigeration plants 175 to 185. Then the filling density of turf mould is given as 161 that is also incorrect. Chairman: Permit me to explain that. The matter is as follows. Nusselt made use of materials of this density in his experiments and the figures for heat conduction refer to these densities also. It is not said, however, that this is the density of the lamellar carbon. Lamellar carbon may be had, in fact, in various densities. Prof. Dr. Oskar H. Knoblauch (Germany): With data given by- Nusselt it is necessary in the first place to settle what material has been examined. What the densities are under other conditions is of no consequence. In the case of the material that Nusselt experimented on the densities were those given. Experiments have been made by Dr. Gruber concerning the influence of the density, and by these it has been proved by calculation in what manner the figures for the conduction vary. It is quite evident, as Nusselt proved, that there must be a lamellar carbon, and also other materials with another density, but in the samples he experimented upon this was the density. The figures given by Nusselt are absolutely authentic. Val. Allent Noodt (Germany): How did you arrive at the figures for the water absorption in table VIP - Ing. Max Grünzweig (Germany). The table contains data of the experiments conducted at the university of Karlsruhe, in the technical experimenting department, on Expansit granules No. 3 and lamellar carbon. Val. Allent Noodt (Germany): I have before me the results of an experiment which Geheimrat Mo 11 i.er carried out in Dresden, but which gave very different results. I believe that a water absorption such as is given here can only happen if the material, that is the whole building, be submerged under the water, which naturally never occurs in practice. 303 - Ing. Max Grünzweig (Germany): Lamellar carbon and Expansit granules No. 3 are principally employed for the insulation of cold storage rooms on ships, and there is no question as to the possibility of the insulation layers becoming thoroughly moistened by the penetration of water. Val. Allent Noodt (Germany): That has never happened yet. (Dissent.) Arthur Porr (Austria): I beg to ask at what temperature Expansit burns. Seeing that latterly — for instance at the burning of the Karrer Lake Hotel — very bad experience has been made with cork plates, the fireproof question gains more and more in importance. Ing. Max Grünzweig (Germany): Expansit cork shows the same qualities under fire tests as does cork stone, which, after having been subjected to fire tests, was passed as a fireproof building material by the authorities. (At that time in Berlin.) Cork and the articles manufactured from it when subjected to fire become covered very quickly with an air-tight coating of Soot which prevents the further spread of the fire, provided always that this has not arrived at any very advanced stage, so that no extremely high temperature prevails. For example one can stand a Bunsen burner for a considerable time under such an Expansit plate. At the spot under which the Bunsen burner stands the material will be entirely destroyed, but the fire does not spread. ^. Arthur Porr (Austria): I should like to ask one more question. How does it happen that the figures given for the conduction of heat of cork and Expansit, '03 to 04 to 05, are so low, while plates of cork such as are employed in practice, usually show the figure '08, rarely '065 for their conduction of heat, according to the binders used The figures given have more of a theoretical value, for in practice only the figures for the conduction of heat of materials which are also made use of in practice are of importance. Ing. Max Grünzweig (Germany): Perhaps Prof. Knob lauch would be best able to give an explanation on this point. Chairman: I think that the matter admits of the perfectly simple Solution that we settle that these figures refer to a certain definite material that has been Subjected to a certain test. Only in this sense can the results be made practical use of Every generalisation can of course lead to errors. In every such publication the figures that are given must be in the first place referred to that material which has been dealt with. Ing. Max Grünzweig (Germany): Perhaps I may make the following remark. If for instance in table IV 042 is given as figure for the conduction of heat, then this represents solely that figure for the conduction of heat which has been found for the material that should be made use of in practice, and of which a piece has been examined in the physical laboratory in Munich. If in practice other circumstances arise that influence the efficiency of the insulation material, such as radiation, dampness, etc., this 304 has, naturally nothing to do with the correctness of the figures for the conduction of heat that are given in the table. These, indeed, must be taken into consideration for each individual case. Prof. Dr. Maryan Ritter v. Smoluchowski (Austria): Under the same Conditions the same results will always bc arrived at. But the same sub- stance of medium specific weight is used sometimes in granular form and Sometimes in the form of a brick, and of these the granular form is invariably the better form for insulation purposes. I should like further to remark that for cork powder that I made myself I found the same figure for heat conduction as for Expansit. Ing. Heinrich Ottmann (Germany): It has been mentioned that in the case of insulation fillings with pumice material (pouring in the material for insulation) the air spaces between the pieces, piled up in layers, amount to about 30–50 per cent. With regard to this I remark that it is possible, in the manufacture of art pumice and the insulation fillings made from it, so to choose the size of grain, from 2 mm upwards, that the air spaces in the layers of these grains are also less than 30–50 per cent, sometimes about 20 per cent. The firm that makes them has it in its power itself to determine the degree of density of the pumice filling by making use of a material with suitable size of grain. (2mm to 5mm and over.) Schiffsbaudirektor Schwarz (Germany): Slight weight and great capa- city for insulation are properties that are of great importance in ship buil- ding. I should therefore like to ask whether the manufacture has advanced so far that it is possible to discover up to what thickness such plates can be turned out, in how far this material can be used in insulating pipes, consequently whether wrappings can also be made out of this material, and whether it is possible to make forms, or if a special treatment would have to be gone through beforehand or afterwards. *. g Ing. Max Grünzweig (Germany): Expansit stone is made in the form of large blocks, from which, by means of suitable arrangements, plates of any desired thickness, or form pieces can be split or planed. Schiffsbauing. Lazarus (Fiume): Could you perhaps give the comparison. in price between Expansit and press cork? * - Ing. Max Grünzweig (Germany): As regards the comparison of price it must be remembered in the first place that for the manufacture of press cork from three to five times as much cork is necessary as for Expansit cork. If one considers that the heat conduction of Expansit cork is much less than that of press cork, then the use of Expansit will be, naturally much cheaper than the use of press cork. . Schiffsbauing. Lazarus (Fiume): Is the material cheaper or dearer per kilo than press cork? Ing. Max Grünzweig (Germany): Of course it is dearer per kilo. But one must at the same time take the insulating effect into consideration. 305. Chairman: I think, Gentlemen, that we are not in a position to con- tinue the discussion. We express our best thanks to the lecturer. In every case it is of great value that here again we have had opportunity to observe a progress in one of the most important insulation materials, and we can only hope that the fruitful competition in this field will lead to the con- tinual furtherance of the question of insulation. K. k. Oberbaurat Dr. Ludwik (Austria): I am quite sure that I may speak in the name of all those present when I express the best thanks to Geheimrat v. Linde for having not only honoured us by accepting the position conferred of honorary president but also devoted his time to us and actually exercised this function. (Great applause and clapping of hands.) Geheimer Hofrat Dr. C. v. Linde (Germany): I thank you most sincerely but I think that the honour was all on my side. Gardner T. Voorhees, United States of America takes the Chair. Alexander Behm (Austria) speaks on Two new app a rat use S for de term in in g the he at c on ducting efficiency of in su 1 a ting m at erial sº. (See p. 194) Chairman: Gentlemen, We have still several interesting papers to hear to-day, so that it will be in the interests of time if we determine that from now onwards 10 minutes shall be allowed for each paper and 3 mins, for the discussion. Charles Pasquai (Germany): I should like to remark that the paper has greatly interested me because I have myself for 25 years past been occupied with such experiments. Further I would remark that I have made use of the Metz tubular testing apparatus of the same construction in principle for about ten years past, but I have made certain other simplifications in my apparatus. In particular it pleased me to see that the speaker has endeavoured to avoid the influence of the end surfaces of the testing tube, as I have also done for the last 20 years. I think that I discern a slight simplification as compared with this testing apparatus in the fact that it is in reality not necessary to cover the collecting vessel for the condensation water with a Steam mantle as well. I inclined my testing tube and placed two partition walls in it. The water of condensation, whose quantity may be observed by means of a water gauge, runs off in a cool serpentine; at the end of this there is a tap. The water of condensation is kept at such a height that no steam can be led off into the conduit pipe. *- Prof. Dr. Oskar Knoblauch (Germany) asks all gentlemen who intend to institute Scientifical experiments on the transmission of heat to determine at the same time, if it is in any way possible, the temperature of the upper surface of the insulating layer. Then one would also have data from which it would be possible to determine the coefficients of the transmission of heat, concerning which there still exists a great want of knowledge, and 20 306 then the transmission of heat could be calculated, for which unfortunately the scientific bases fail at present. Chairman: Perhaps we could form a special committee which should have to devote itself to the question of insulation. I have worked at this question myself for many years. & Alexander Behm (Austria): What the previous speaker has just said is certainly to the point. In the experiments that we institute the upper surface temperatures are always measured of the objects to be examined. In most cases not only are thermo-elements built in the steam heated room in the plate apparatus but such are also affixed to the upper surface and in the material itself. Thus besides the determination of the coefficients of conduction of heat and of the transmission of heat certain further factors are gained which could serve for the calculation of the resistance to transmission. * - For the rest I should merely like to mention that if two solid bodies are layered one above the other, and that without the use of any binders, a layer of air generally forms between these two bodies; this acts as a resistant to transmission, so that the total resistance to transmission is composed of two quantities, out of the resistance of the air layer and the resistance to transmission which in both cases results in the solid material. As Prof. Knob lauch explained, it is certainly very simple and requires no great expenditure of time or money to determine as well the temperatures of the upper surfaces of the objects under experiment, always by means of thermo-elements, in all such examinations and especially also in experiments regarding the determination of the efficiency of insulation materials. Chairman: Prof. Knob lauch has given an impulse. I beg to ask whether the Professor desires that this proposal be laid before the general meeting of the Congress as a wish. Prof. Dr. Oskar Knob lau ch (Germany): This seems to me to be desirable and I would very much recommend it in order that in wider circles also that are not represented here the necessity may be recognised of confirming the valuation of the coefficients of transmission of heat by experimental data. - g Chairman: I would then request the formulation of the proposal. Prof. Dr. Oskar Knoblauch (Germany): I should propose : The Commission shall decide: *That it is desirable that in all experiments concerning the transmission of heat the temperatures of the upper surface of the insulating layer be simultaneously determined, in order to make it possible to calculate in a reliable manner the coefficients of the transmission of heat which comparatively speaking have not yet been very exactly determined, and consequently be able to make scien- tific application of the results of the observations<. Chairman: Will those Gentlemen who are in favour of the proposal kindly raise their hands The proposal, is accepted. 307 I call on Direktor Friedrich Rudolph Metz for his paper on "The insulation value of hollow layers in theory and practices. “... Ing. Friedrich Rudolph Metz gives his paper. (See p. 239) Chairman: I call on Ing. Oberstleutnant D. Jakow leff for his paper on 2 The economy and statistics of the m an age m ent of he at in the production of artific a 1 c old. Ing. D. Jakowleff gives his paper. (See p. 273.) - Chairman: As the Gentlemen can see from the printed paper, there is attached to it a plan of a query. Schedule. Has any gentleman any remark to make with respect to these questions or their arrangement? º Prof. Hugo Seidler (Austria): I should like to draw attention to the fact that it is not possible to give a final decision about this immediately. Either the paper of Oberstleutnant Ja ko w leff should be handed to a sub-committee created by the II* Commission to be studied, whose report should be laid before the next sitting of the Commission — the time at disposal, however, is not sufficient — or the matter might be handed by the general meeting of the Congress to one of the existing international Commissions, on the basis of a report of the II* Commission, with the request to report thereon to the 3" Congress. Chairman: I can only describe the composition of the query Schedule as very successful. It is a matter of no slight importance that the owners of ice and refrigerating plants give due consideration to these questions. Ing. D. Jakowleff (Russia): I think it would be good to express a wish with regard to this to the Societies of Refrigeration and these could report to the next Congress. Prof. Hugo Seidler (Austria): We might then formulate that in the following manner: >The Commission expresses the desire that the Congress request the Societies of Refrigeration to study the questions brought forward by Oberstleutnant Jakow 1 eff. Chairman: I ask those gentlemen who are in favour of this to raise their hands. I beg for the counter test. The proposal is unanimously accepted. This desire of the Commission will be laid before the Congress at the general meeting. Wilhelm Figdor (Austria) gives his paper on 2 Cement wood as an in sulating materials. (See p. 219) - Chairman: As the time is already very advanced I recommend that a possible discussion of this interesting paper be left till the next sitting. To-day's sitting is closed. , ºf 308 4* Sitting, Io" October, 1910. The Sitting began at 10:30 a. m. and ended at 1:45 p. m. Honorary Presidents: Gardner T. Voorhees (United States of America) and Ing. A. Barrier (France); President: k, k. Oberbaurat Dr. Camill Ludwik (Austria); Vice-Presidents: Prof. Hugo Seidler and Dr. Richard Jahn (Austria); Secretary: Ing. Richard Kurs sa (Austria). --- The Chairman opened the sitting and called on Mr. Figdor. Wilhelm Figdor (Austria): Shortly recapitulated his paper given at the last sitting, on 2 Cement Wood as an Insulating materials. Chairman: Does anyone desire to speak respecting this paper? (No one rises.) We pass to the next point on our programme, namely a short additional paper on experiments on cork that have been made in America. W. M. Whitten United States of America) gives a paper on Methods for exam in in g the in sulation of cold plants and comp a rative results. (See p. 249.) § Chairman: On this subject there will be no discussion, as the paper was not previously announced and the time is too short in consideration of the length of our programme. - The paper will be printed and will then be at the disposal of the Gentlemen. G. C. Bertsch (United States of America) reads the paper by Peter Neff on: 2 Tests of m a terials and p a r ts used in the construction of refriger a ti on a pp a r at uses, Unification of these conditions determ in a tion of rules a n d me th o ds by the Inter nation a 1 Commission.< (See p. 174) * - Prof. Hugo Seidler (Austria) reads the proposal of Mr. Neff in German and recommends that the proposals which must be variously judged by the individual countries be handed over for study to the existing National Societies of Refrigeration with the request to report to the next Congress. Chairman: I open the discussion on the proposals of Mr. Neff. (No one desires to speak.) The French delegates state that on the completion of to-day's programme they will put forward some resolutions; one of these refers to a matter similar to that dealt with by Mr. Neff. - The vote will, therefore not be taken on Mr. Neff's proposals until after the discussion of the before mentioned resolution. Ing. Albert Barrier (France) takes the Chair. Direktor Karl Heimpel (Austria) speaks on Technical in ter- ven ti on in the building a n d working of co I d plants by the National Societies of Refrige rations. (See p. 268.) Chairman: I thank the speaker for his interesting paper and open the discussion. Obering. R. Banfield (Germany): I must say I entirely agree with the lecturer; in a business way the working out of projects by any one Centre can never be carried out. 309 The initiative of the individual manufacturers, the peculiar way of working out the projects and constructions of each maker on the basis of his own experience and thereby progress and the prosperous development of refrigeration matters would be stopped. (Cheers.) G. C. Bertsch (United States of America): In the name of the delegates of the United States I should like to ask the Commission to support the proposal of Direktor Heimpel and to abandon the proposition relating to the intervention of the National Societies, or of the International Association in the settling of contracts, or the execution of cold plants. . The most varying conditions, methods of manufacture, commercial customs, etc., render such an intervention as is proposed absolutely impossible, and we Americans cannot agree with such a proposal, because it would hinder progress and is contrary to the laws of trade and commerce. I beg the Gentlemen present to agree to the proposal of Direktor Heimpel. Obering. Tegetmeyer (Germany): I should like to confirm what the last Speaker has said, being fully convinced of its correctness. The experiences made in Germany in contracting for large plants, for instance for slaughter-houses, make it appear practically impossible to deter- mine international regulations for the conferring of refrigeration machines, etc. Prof. Hugo Seidler (Germany): To shorten the debate I beg to propose the following resolution: »The II* Commission is in sympathy with the statements of Director Heimpel and proposes that the Congress resolve: It is left to the Societies of Refrigeration, according to the degree of the local conditions, to regulate their activity in the sense of the above question, and the study of the comprehensive paper by Director Heimpel is recommended.< I propose further: *That Director H e i m pe 1 be thanked for his excellent paper.< The Chairman proposes: That the National Societies of Refrigeration be applied to for advice by the buyers and sellers in working out the purely technical part of contracts and should intervene to the advantage of both sides, in the superintendence of the building, at the trials and the periodical testing of apparatuses and refrigeration plants; that the conditions of this intervention should be studied separately by each of the National Societies of Refrigeration, and that later on, on the basis of these studies, consistent and final regulations for intervention be drawn up by the Association Internationale.< Director Karl Heimpel (Germany) speaks against the proposal of Mr. Barrier and repeats as reason for his attitude the relevant portions of his paper. (Cheers). 310 Prof. Hugo Seidler (Austria): I beg to state that the Chairman has just consented to omit that part of his proposal according to which after the study of these matters by the individual Societies of Refrigeration the Association Internationale should draw up uniform regulations for the planned intervention, so that the two resolutions of Mr. Barrier and that drawn up by me from Mr. He im p e l’s now agree in sense. I therefore withdraw the first part of my proposal, but on the other hand I maintain the second part of my proposal which expresses thanks to Mr. Heimpel Director Karl Heimpel (Austria); I beg that the proposal of Mr. Barrier be read again. * * & - Prof. Hugo Seidler (Austria) reads the altered proposal of Mr. Barrier : * That the National Societies of Refrigeration be applied to for advice by the buyers and sellers in working out the purely technical part of contracts, and should intervene, to the advantage of both sides, in the superintendence of the building, at the trials and the periodical testing of apparatuses and refrigeration plants, and that the conditions of this intervention should be studied separately by each of the National Societies of Refrigeration «. º - Ing. Konrad Pusch (Hungary): I recommend that the proposal of Director Heimpel be accepted, as it is not possible that the National Societies of Refrigeration spend their time on revision of plants, construction, etc.; inconsequences would arise from the occupation of the members, and the Societies of Refrigeration would make business like the boiler revision societies, which would not be in accordance with their objects. Ing. E. Brandt (Germany): I beg that the proposal of Director He i m p el be put to the vote and urgently recommend that this proposal be accepted as an expression of the opinion of the 2" Commision. It is absolutely out of the question that so far-reaching a regulation as is demanded in both of the other proposals, be it through the Association Internationale or through the National Societies, can prove a blessing to the refrigeration industry. The very opposite would result and every independent continuation of work and all progress would be stopped, whereas the proposals of Director H e i m pe 1 are Suited to open up ways of further development in every province of the Refrigeration industry. Prof. Hugo Seidler (Austria): I beg leave to say that in my opinion the resolutions of Mr. Barrier and Director He impel are the same in sense. (Cries: O no!) In the first part of Mr. Barrier's proposal the concerns and work are given, with regard to which the cooperation of the refrigeration societies or their expert opinion could be given. Herr He impe 1 then in 1–5 lays down definite proposals which refer to such an intervention, and recommends that in the relative cases mentioned the Societies of Refrigeration could act as expert delegates. Those, however, are instructions regarding execution which in the sense of both proposals, should be dis- cussed and fixed by the Societies of Refrigeration individually (that is ºf 3.11 independently); for the second part of the altered proposal of Mr. Barrier runs, that the conditions of this intervention should be studied by each of the National Societies of Refrigeration separately, and Director Heimpel says at the close of his proposal: "It is left to the National Societies of Refrigeration, according to the degree of local conditions, to regulate their- activity in the sense of question 104. - * Ing. E. Brandt (Germany): I should give the preference to the wording of Direktor He impe 1. f Prof. Hugo Seidler (Austria) reads the proposal of Direktor Heimpel which he drew up: *The II* Commission is in sympathy with the statements of Direktor Heim pe 1 and proposes that the Congress resolve: It is left to the Societies of Refrigeration, according tho the degree of the local conditions, to regulate their activity in the sense of the above question, and the study of the comprehensive paper by Direktor Heim pel is recommended.< I think that in the interests of a quick settlement it would be best that we discuss the proposals of Direktor Heim pel and Mr. Barrier. Direktor Karl Heimpel (Austria): We shall get no further if we do not once more read the proposal. -- - Prof. Hugo Seidler (Austria): Your proposal drawn up by me is copied from your paper. Here is a printer's Proof. - Direktor Karl Heimpel (Austria): I made a further and more compre- hensive proposal. I should like in a few words to repeat the introduction to my proposal, perhaps it will serve to make the sense of the whole more clear. (Reads from his paper the lines beginning In spite of the many well founded doubts. . . . . down to [delegieren] intervene.) The society will only do that on demand and will not proceed as an authority. I would like to ask that my proposal be put to the vote in this shape and that the II* Commission declare their agreement with my proposal. (Cheers.) * Prof. Hugo Seidler (Austria); May I remind Direktor He impel that there, must be a concise and definite proposal which after having been accepted by the Commission must be submitted to the general meeting. For that reason I compiled the proposal from your paper. The Chair man, Mr. Barrier, requests me to state that this question 10 in the propramme of the international Commission was accepted at his request, in order to make the question clear whether the Societies of Refrigeration should intervene at all or not. The proposal of the Chairman Mr. Barrier is only a suggestion as to the manner in which the question might be settled. Its formulation remains for the Commission to effect. I should like to ask Direktor Heim pel to state if the proposal agrees with his explanations or if there are any alterations that should be made, because we must have a definite and concise proposal. (Hands Direktor He impel a draft of the proposal. [See above.]) 312 Direktor Karl Heimpel (Austria): I should like to change just one word; then I declare my absolute satisfaction. The proposal would run (reads): *The II* Commission agrees with the conclusions . . . etc. It would read then x conclusions & instead of >Statements. < * Prof. Hugo Seidler (Austria): Direktor He impe l’s proposal runs therefore (reads): "The II" Commission agrees with the conclusions... etc. I have taken the liberty to add; "And the study of the comprehensive paper by Direktor Heim pel is recommended.< (See p. 268.) *. I have found that the statements of Direktor He impel are excee- dingly interesting and important and have therefore added this. The proposal of Direktor He impel was unanimously agreed to, so that the proposal of Mr. Barrier was withdrawn. - Prof. Hugo Seidler (Austria): I beg once more to suggest that the Commission express thanks to Direktor He impe 1 for his excellent paper. (Great applause.) Prof. Elger v. Elgenfeld (Austria) gives his paper on 2W or king pressures and effects of cold air turb o-m a chines.< (See p. 123.) The Chairman opens the discussion on this paper. Prof. Dr. Hans Lorenz (Germany): I think that the previous speaker judges the matter too unfavourably. Progress can still be made when the pressure interval is diminished, namely by limiting oneself to atmospheric Suction tension. * Prof. Elger v. Elgenfeld (Austria): That depends on the temperature. I have, as a matter of fact, only taken the extreme cases. Downwards I could not go, because we then get too high a temperature of the returning air. Prof. Dr. Hans Lorenz (Germany): I think that for normal grades of temperature one can still further decrease the pressure interval by means of counter current effect in the cooler, and thereby improve the efficiency of the energy of the turbo cold air machine; but without exact calculation I should not like to express a final judgement. Ing. Juppont (France) gives his paper on 2The electrical trans- mission of power and the application of cold K. (See p. 282.) Chairman: At the Congress in Paris the resolution was passed that the authorities or the municipal councils should be applied to respecting more favourable rates for the supply of water that was to be used for refrigeration plants. An analogous wish was expressed at that time with regard to the supply of gas and electrical energy. The wording of these resolutions may be seen from the reports of the I* Congress. The proposal of Mr. Jupp ont aims at securing that the question raised by him be dealt with in detail by the national Associations of the Refri- geration Industry and passed on to the electro-technical Societies for study and formulation. This should also take place for the purpose of enabling electricians to express their views as to what steps could be taken to effect 313 a lowering of the price of electricity and simultaneous determination of the conditions of supply. The proposal of Mr. Jupp on tº was accepted in the following shape: »In order to explain to electrical entreprises (Central stations) the interest that they have in a reduction of the prices for current supplied to the Refrigeration Industry the National Societies of Refrigeration are requested to draw up a summary of the spheres of application of cold in the various industries and to hand this to the electrical scientific and technical societies of the different countries.< - Chairman: This proposal will be laid before the general meeting of the Congress. & & I call on Mr. Juppont (France) for his paper on "Cellular heat storers, System E. Brousse. (See p. 233.) Prof. Hugo Seidler (Austria): M. Sandras (France) has submitted a broschure on 2 The manufacture of ice <. The question should, properly speaking, be dealt with by another Commission, but this paper has been allotted to the II* Commission. As there is no proposal contained therein we might omit the reading of the paper, which will, of course, be printed in full in the reports of the Congress. (Agreement) (See p. 901.) Chairman: There is here an elaboration by Mr. Paul Gasnier (France) on the ‘Cooling of electrical enginess. (See p. 257.) Mr. Gasnier is not present; I should like to avoid reading the whole paper and to give the contents briefly: Mr. Gasnier dealt with the question of loss of energy in electrical engines (generators, electro-motors, transformers) which change to heat, and with the question as to the steps that might be taken to lessen this loss especially in the case of engines of great power. Propositions and data regarding the results of experiments are not given, but it is merely proved how desirable it is that both refrigeration technicists and electro-technicists should take this matter into consideration. As by this a new sphere of application of refrigeration might be created I propose the following resolution: »The National Societies of Refrigeration shall cause artificial cooling processes for large dynamos to be studied, for the purpose of examining whether the degree of efficieny of the latter admits of being appreciably increased thereby K. This resolution was accepted. Chairman: Mr. Paul Andrault (France), who is not present, has submitted a paper entitled "Experiments on air coolers with ripened and with wet upper surfaces, their advantages and disadvantages.<. Is is perhaps unnecessary to read the paper. (Agreement.) The paper will be printed in full in the reports of the Congress. (See p. 119.) I recommend the same procedure as regards the treatment of the following reports submitted, which contain no resolutions and whose writers are also not present. (Agreement.) 314 G. Gillman (France): 2Safety measures for the prevention or lessening of damage to compressors and conduits. (See p. 144) Mr. Masse (France): * Insulation material. (See p. 234.) t Dr. J. Siebel (United States of America): *The application of super- . heated steams in artificial refrigeration «. (See p. 182.) & Lauritz Nilsson (Sweden): "The present standing of ice cooling technics and their continuation in Sweden. (See p. 283.) --- Chairman: The proposal of Mr. Neff was withdrawn. I beg you to have patience for a little longer, as we have still to finally formulate the resolutions that we have to lay before the general meeting. I propose the following procedure, that these resolutions, together with those already decided at the I* International Congress of Refrigeration which have so far not received any final treatment or settlement, be submitted in compre- hensive form. -- t The resolutions of the II* Commission (See p. 1141) were then read separately and the new proposals, accepted in the course of the sittings of the Commission, were put into text. It was decided not to take up the resolution by Direktor He impel, respecting the technical intervention of the Societes of Refrigeration in the technical preparation of contracts, question 10, as the American delegates, maintaining the adverse position they took up in the debate, pronounced themselves equally against a resolution on the point; moreover, this question, by the position taken up or by the decision of the Commission, had already been settled by the Commission in the desired sense. COMMISSION III. Application of Refrigeration in the Food Industries. 317 The respective comparative values of frozen and chilled meat from the point of view of general consumption, and more particularly of the provision of the army, the navy, and public and private administrations. - By H. Martel, Doctor of Science, Head of the Veterinary and Sanitary Inspection Service in Paris. It is a common place to say that the employment of artificial cold con- stitutes at the present time the best means of preserving meat. There are distinct methods of employing cold; meat is said to be frozen when cold- at a very low temperature freezes it to the core slowly, or more or less quickly; it is said to be refrigerated when the cold is not sufficient to soli- dify the juice in the meat; a third case arises when the use of artificial refrigeration is combined with that of preservatives such as salt and formal- dehyde, for instance, in order to attain longer preservation. Meat preserved in cold chambers undergoes there radical modifications which make it more tender and more juicy. The preference generally shown for seasoned meat, that is to say, for meat which has been preserved for several days at the ordinary temperature such as that which is produced in countries which do not use cold rooms, would be more justly shown for meat refrigerated and preserved during several weeks at 2 or 3 degrees below zero Centigrade. The Germans say of this meat preserved by cold that it undergoes a special maturing process. This expression, which accurately describes a phenomenon whose economic importance is considerable, ought to be borne in mind. Overlooking the works of A. Gantier and L. Landi") on the products resulting from the action taking place in muscle separated from the living being, and on the germ life in the tissues, Glage”) thought it possible to compare the action in maturing meats, preserved in cold enclosures with that which takes place upon pastes of cheese in the same enclosure. Assu- *) A. Gautier and S. Landi Ann. de phy, et de chemie VIth series, volume XXVIII, Jan. 1893. *) F. Glage, Zeitschrift für Fleisch- und Milchhygiene, 1900/01, page 131. 318 * ming the existence in the cold rooms of bacteria, Aromabacterien", capable of setting up special fermentations, he arrives at the conclusion that, in numerous cases, the microbe in the meat may perhaps resemble that in milk and cheese, and that the oaromatic" bacteria must play a part in the phenomena of maturings. This amounts altogether to a simple point of view"). The comparison made between the preservation of cheese and that of meat should be con- sidered because of the fact that milk and flesh are often exposed to the same sources of contamination ; nevertheless, on looking into the problem more closely, and remembering the researches of A. Gautier and L. Landi, we cannot accept this explanation. & * M. Muller”) has reminded us that in the cold rooms of abattoirs, a temperarure of 2 or 3 degrees coes not hinder maturing, while, it prevents setting up of putrefaction *). * - On analysing the properties of fresh meat and those of meat preserved at a low temperature, but not frozen, M. Muller insists upon the existence of modifications which characterize the maturing process, and which are such that butchers, particularly desirous of satisfying the tastes of their customers, give their preference to preserved meat"). Certainly he does not deny the influence of the age and breed of the animal and various other well-known factors; but, in common with all the hygienists who are engaged on this question, other things being equal, he gives his preference to refrigerated meat. r Under the influence of the maturing process, meat undergoes appre- ciable modifications the naked eye. The muscular fibre which was in fresh and brilliant condition, and of a translucent appearance, becomes dull and opaque. The consistency of the meat is altered more or less: in the fresh state this is such, that when the fingers are pressed on it they can not sink in ; later, after a certain period of preservation, it becomes tender and easily fried. ^ The reaction of live meat is neutral ; it is not long in becoming acid immediately on the coagulation of the myosin, and upon the appearance of the rigidity of death. According to M. Muller, at the end of the eighth 1) See on this subject L'hygiene de la viande et du lait, 1907, page 1. *) M. Muller, Zeitschr. für Fleisch- und Milchhyg. 1903/04, p. 217. *) The same argument was pointed out to us some time ago by our colleague, Huon of Marseilles upon the sub ect of the microbe theory of the internal modifications which take place in meat called ,Feverish". * *) The value of the flesh of the ox, says Pages (L'hygiene pour tous, p. 231, 1905) varies with the way in which it has been preserved. . For boiling, meat can never be too fresh, for roasting it should have 2 or 3 days preservation. Pages thinks that meat preserved for a longer period loses its succulence and its nutritive value, more or less, according to the temperature. — We think that under the more or less defective conditions for the preser- vation of meat, which have always existed in France, the argument has a certain value, But it has none now that perfect refrigerating installations are available. * 319 day of its preservation in cold rooms, meat attains a high degree of acidity, and gives forth a peculiar smell, aromatic and of clean acidic taint. This smell bears no resemblance to that of putrefaction. A Preserved meat becomes rich and succulent. Cut up into little pieces and submitted to a hydraulic pressure of 1000 kilogrammes per Sq. cm. meat taken a little while after slaughter only yields an insignificant amount of juice, while it retains 75 per cent of its combined water. One or two days of preservation, that is to say a sufficient time to allow the rigidity of death to disappear, is still too short a period to allow of the extraction of the meat juice. It is at the close of the third day that the meat, on undergoing pressure, can yield large quantities of essence. The maturing of meat is also characterised by modifications in the muscular fibre, appreciable upon microscopic examination; the muscular stringiness disappears, and a destruction of the fibre is often observed, it being transformed by the production of abundant granulation. Maturing cannot be likened to the commencement of the process of putrefaction as Hammarsten states. The special flavour of refrigerated meat does not depend on the existence of Special bacteria (Glages aromatic bac- teria). Two kinds of proof show this. On the one hand it is known that healthy meat provided by animals slaughtered under good hygienic conditions and sufficiently long after a meal does not contain microbes. When microbes enter into the system, thanks to frequent digestion, they collect in certain tissues such as the marrow of the ox. After death, meat provided by healthy animals is not easily penetrated by saprophytic microbes (Presuhn, Portet, Forster). Hardly at the end of ten days (Forster) can microbes be found at a depth of 1 centimetre from the surface. On the other hand, authors who have studied the various phases through which meat passes when preserved at a low temperature, have stated that an actual self-digestion takes place in the meat. A. Gautier and L. Landi state that meat preserved at 0° C slowly changes under the action of soluble ferments. According to A. Gautier ,Among the fermented products of meat there exists a sort of trypsine, which acts even during life, because the peptone which is found in meat juice, does not appear to be all formed after death. If this self-digeation in the meat is prolonged, it makes it tender and easily digested. . . . The digestive ferments in acting upon meat at from about 8° to 15°C, partly liquify it, and produce a slow oozing of juice which rises to 3°/s in ordinary beef, but which is more abundant in the case of chilled (or frozen) meat." The action of a cold temperature varies according to the degree of refrigeration attained. While temperatures below 0°C render the peptone reagents in meat inactive A. Gautier]"), low temperatures above 0 C such *) Is is known that pepsine does not act below zero centigrade, and that trypsine acts very slightly at this temperature, especially in an acidulated substance such as meat. (A. Gautier L. C. page 33.) 320 as those employed in the cold stores of abattoirs and places for the pre- paration of meat, still allow of the action of the ferments. This takes place at a low temperature and it becomes very active at a temperature of from 15° to 20° C. At these temperatures A. Gautier and Landi have observed the production of raw albuminous substances formed at the expense of the soluble albuminoids in the meat. When meat is preserved long enough at temperatures below 0°C, that is to say, when it is frozen, the alterations which still take place are not of such a kind as to lessen its nutritive value. In this particular case which is not met with ordinarily in the modern abattoir, but which is of great importance in the use of refrigerating plants in time of war, we can- not do better than reproduce in full the analyses and results of the remar- kable work of Professor A. Gautier.”) The preservati on a n d maturing of meat. Comparison between fresh and refrigerated meat. Composition per cent. Mutton (Shoulder) Beef (rumpsteak) Substance fresh refrigerated fresh refrigerated 5 to 6 months 5 to 6 months at 50 C. at 50 C. Water . . . . . . . . . 74-92 73°66 74-75 73-96 Globules containing a little albumen corresponding to the part of the meat Soluble in water . . . 3:32 2: 14 3.06 2’69 Teptoncs . . . . . . . . 1 33 1:29 2.24 2:56 Myosin . . . . . . . . . 8:31 10:33 10.96 9:29 Myostroine . . • y. - A 4:49 4'04 4:30 6°41 Indigestible matter (Kera- tin & Elastine) . . . . O'86 O-75 O'24 O'94 Extracts (ferments leuco- maines) . . . . . . 0.49 O'95 - 0-97 1.01 Glycogen . . . . . . . O'40 O'03 0.38 O'16 Fat & Cholesterine . . . 5:23 5'38 1.98 2:04 Soluble Mineral Salts . . O'60 O'53 O'65 O-47 Insoluble mineral salts . . O'65 O'44 O'44 O'44. 1OO-52 100:24 99.96 100:02 Fresh Meat Refrigerated Meat. Mutton Beef Mutton Beef. Dry extract of parts soluble in cold water . . . . . 5'84 6'92 5'3 699 *) A. Gautier, l’Amentation et les Regimes Paris 1904, p. 192. 321 Fresh Meat Refrigerated Meat. - *. Mutton Beef Mutton Beef. Dry extract after the coa- gulation by heat of the * ... albumen & globules . . . 2-52 3'86 3:20 4'50 Dry extract of soup ob- tained by boiling chopped meat with excess of water for 8 hours . . . . * 3'37 3-98 3:62 4.17 Gclatinous part of the meat by heating to 115°C the insoluble residues in the Water . . . . . . . . 2-72 2:56 2’69 2:15 Muleinic acid . . . . . . 0.56 O'44 O'591 O'66 Substances reduced from meat hardened in Glycose O'191 0.24 O-171 O'O1 1. Meat (American) refrigerated and preserved several months at 3" or 4" below zero C, contains about 1°/o less water than good butcher's meat in our country (France) left one or two days in the open air. 2. In 100 parts by weight of this refrigerated (or frozen) meat, have been found digestible albuminoids amounting altogether to: Soluble Part Insoluble Part Total In Mutton . . . . . . . . . 343 15:27 1S-70 In Beef . . . . . . . . . . 5:25 15-70 20:95 The albuminoids are in a slightly larger proportion 1n this meat than in fresh meat. Fresh Meat Frozen Meat Mutton . . . . . . . . . . . . . . . . 17:42 1878 Beef . . . . . . . . . . . . . . . . . 2056 20:95 3. Far from being more gelatinous than fresh meat, as has been asserted, frozen meat is rather less so. 4. Fatty substances are equivalent in composition and weight in fresh meat and meat preserved by a cold temperature, but in the latter there is a slight flavour of suet which often makes it possible to recognise this meat after roasting. -*. 5. Extractible substances are not perceptibly more abundant in refri- gerated meat and glycogene is produced. But this last seems to disappear more and more during preservation. 6. Contrary to what might be expected from a slow gradual alteration of albuminous substances, by the natural ferments in the tissues, leucomaine which have changed to the state of phospho-molybdates (a change pro- duced by peptone) are slightly less in frozen than in natural meat. 7. The parts of this meat acted on by peptone, are not perceptibly changed during refrigeration. & --- 21 322 . Peptone in 100 parts of meat. Fresh Meat Frozen Meat Mutton . . . . . . . . . . . . . . . . 133 I-29 Beef . . . . . . . . . . . . . . . . 2:24 1.56 8. When this meat is allowed to reach the ordinary temperature before being used, there is produced under the action of its own ferments a fairly rapid partial peptonisation, which contributes towards the formation of a more abundant quantity of juice than that which fresh meat yields, which has given rise to the belief that it changes or decays very readily. It is supposed that, because it has been frozen, the cells in the fibre break, and, upon thawing, allow their protoplasmic liquid contents to flow out. This idea is quite incorrect, Dr. Letulle who has made in the refrigerating room itself a close microscopic examination of incisions in frozen muscular fibre, has stated that it is perfectly intact, and that neither crystal of ice nor any sort of breaking up of the fibre can be discerned. 9. The flavour of refrigerated meat, when cooked, differs from that of ordinary meat by a slight greasy taste. Boiled refrigerated meat is excellent and difficult to distinguish from ordinary meat. 10. Its digestibility by the gastric juice of a dog, or by a mixture of active pepsine and hydrochline acid at 1000" is identical with that of natural meat. & Already in 1874, H. Bouley') speaking about the Tellier Process in a report made to the Academy of Science, has said "It is not necessary for the cold room in which the meat is preserved”) to be maintained strictly at 09 C; experience has shown that the temperature may vary between + 30 and —2° C. The large pieces can remain much longer unputrefried in the cold room, than the medium, or the small ones. The length of time of preservation in a cold chamber may be considered indefinite as far as putre- faction is concerned, but it is not at all the same from the point of view of edibility. Butchers meat preserved for 40 or 45 days preserves its quali- ties perfectly. It is even true to say that they improve from this point of view during the first week, in the sense that, while preserving their flavour they gain in tenderness, and are hence more digestible.< The study of the changes which take place in meat preserved at 20 or 30 in the cold room has been the object of recent researches made in the course of the last few years. Working upon sterile meat, M. Muller") has observed the phenomena of self-digestion equally at temperatures of 1) Bouley Comptes rendus. i. XXI p. 739. (Report representing a commission found bº Milne-Edwards, Peligot and Bouley). - 2) The experiments were carried out upon Butchers meat, fowls, pieces of game and shell-fish. $ 3) M. Muller, Archiv für Hygiene, t, XI, VII, page 123, 323 20 and 0° C.) M. Muller arrived at the conclusion that the self-digestion which takes place during its stay in the cold chamber, affects the whole mass of the meat. The changes which meat undergoes are not arrested by the temperature of 29 to 6° C which exists in cold chambers. Self-digestion is made slower by low temperatures, and maturing is not complete until at the end of 2 or 3 weeks of preservation in the cold room. Long usage has consecrated the alimentary value of frozen meat. It will be advantageous nevertheless, to undertake experiments in the army for instance, in order to ascertain the coefficient of practical usefulness of its meat. It would be interesting to know if stale meat has a staminal value equal or superior to fresh meat. Differences exist from the point of view of digestibility. Unfortunately experiments upon this subject are as yet too few to enable us to give any definite conclusions. Frozen meat stands handling well. All that is required is simply pro- tection of the surface against accidental soiling (by packing in sacks) so that the product may retain a good appearance and all its qualities. The carriage of pieces of meat as hard as ice is easy. In England they consider it sufficient to place the frozen pieces in wagons provided with a double insulating partition, in order to carry them from the refrigerated boats to the towns where they are to be consumed, that is to say over a distance of several hundred, and at times, as much as one thousand kilometres. Frozen meat takes a long time to loose its coldness, in the same way as it takes a long time to freeze it when this is accomplished by the method of slow freezing, of which we have spoken, at –5° C for example. By means of a Meylan-Arsonval thermo-electric needle, made at the sugge- stion of M. Bordas, it has been possible to establish, in the course of experiments performed for the statistics of the Minister of War, that equi- librium between the interior temperature and the surface temperature (— 59 C). In a leg of small volume, is not arrived at until after several weeks. Meat being on the whole a very bad conductor of heat, it follows that the warming up again of frozen meat takes place equally slowly. In practice, in order to keep the good appearance of the meat, and, above all, to prevent the meat juice from running to waste, which results from exces- sively brisk thawing, care is taken to place the frozen meat in a cold room at a low temperature of a few degrees above zero C. In London we were enabled to visit thawing rooms, arranged to catch as fast as it is produced “the water vapour emitted in the course of thawing. The work is carried on in rooms warmed from below at 16 to 189 C and cooled again at the ceiling *) Salouski and Hoffmeister employed chloroform to hinder the growth of microbes at the same time verifying the self-digestion of meat after death. 21% 324 by a circulation of brine at 229 below zero C. Frost is deposited on the ceiling, thawing takes place in 14 hours in a dry atmosphere. (The wet bulb of a wet, and dry bulb thermometer indicates 7° C while the dry bulb indicates 14° C) Frozen meat keeps a long time after leaving the freezing room. It may in fact be transported from place to place and used for eating for 5 to 6 days. The War Office majority commission, has just made experiments confirming this. - Frozen meat takes up little room; it is, perhaps, stored loosely, as is usual with somewhat perishable foodstuffs. This peculiarity is important. For a cargo of 150,000 sheep carcases, weighing 4200 tons a space of 10,749 cubic metres"), (380,000 cubic feet) is sufficient. The unloading takes place in batches of 30 or 40 sheep at a time (weighing one ton). The sheep carcases are conveyed down shoots by their own weight from the hold to the refrigerated wagons which carry them, having been carefully wrapped up in a light sack of muslin or cotton. . - - Almost all the German Army is supplied, as is a large part of the civil population besides, with meat preserved in cold rooms at +2° to + 4° C. Moreover the army often receives frozen meat. In war time the refrigerating power of the public abattoir and private installations, distri- buted about different parts of the territory is such that reserves of meat for many months can be stored. This is an important point which cannot be considered too carefully”). - - - • , Erigland, accustomed for a long time to consume frozen meat coming from her distant possessions (Australia and New Zealand) and from the Argentine Republic, would not supply any other kind of meat in case of war. The English soldiers generally consume imported meat, for the good reason that it is very good as to quality, and very low as to price. During the campaign in the Philippines and Cuba, the United States of America rightly considered that meat preserved by artificial cold formed the best rations. - In the same way the English during the Boer War, made use of cold for the preservation of meat with great success. According to Colonel Richardson, Frozen meat saved South Africas. This is the reason that the English maintain depots for refrigerated meat in their distant possessions, and along the route to India : Gibraltar, Suez, India, etc. . . . - In a general way it may be said that the greater number of foreign countries are constructing or already possess vast cold storage warehouses, and that, in case of war, meat preserved by cold will play a part of con- siderable importance, of which the campaigns of Manchuria, The Transvaal and Cuba only give an imperfect idea. . . . . . . 1) Millon 1st. Refrigeration Congress p. 739, t. 3. - . . . . . . . . 2) The prolonged preservation of meat at a low temperature (+ 2 to + 4° C) has the advantage of destroying parasites such as the «cysticerques in beef, the assimilation of which can set up taenia (tapewoi Ins) in man. - * , . 325 We have seen that, frozen meat keeps a very long time in practice, and is especially adaptable to the victualling of troups a long way off. In England the people consume large quantities. Refrigeration provides healthy and plentiful nourishment at a low price. * It is noteworthy that for some time, frozen meat has also tended to become a product which may be transported over long distances. This result has not been attained without difficulty. The first batch of frozen meat which was exported from New Zealand in 1894 ended in failure. Other attempts made in 1895 (from Brisbane) in 1896 (Bowen) also ended in failures. We have taken part in the attempts made in 1905, to transport refrigerated mutton, from Arzew (Algeria) to Paris. The first arrivals were in fairly good condition. Unhappily some other batches proved partial failures, which discou- raged the promoters at the head of this enterprise. The failure resulted from defective work in slaughtering and handling, and the necessity for tranship- ment at Havre which occupied an interminable time"). . Since 1901, the Argentine Republic has despatched meat to England, refrigerated at a temperature in the neighbourhood of freezing point, 29° to 319 F, or about 1° below zero C. Variations in temperature are observed on route, but as th are slight, the meat arrives in a good state of preser- vation. The piec s are somewhat hard on leaving the ship, without however, being frozen. We must add that the River Plate also places refrigerated meats upon the London market, to the amount of 30,000 tons annually”), coming from the United States. In respect to successful attempts made in the year 1909 by the Lind- ley process, we have the assertion from Mr. Linley himseIf that the tempe- rature of refrigerated holds should never be as high as 32° Fahrenheit, or 0° Centrigrade. The accounts which were given to us Dec. 23 last on bo- ard the Guardiana" at London indicated that the temperature had been maintained constant at 31° F. Mr. Linley has assured us that variations between 28° and 31.5° F (–2° and —2° C) are without risks in preserving meat 3). ~, *) The manner of handling as practiced in the factory at Arzew is imperfect. We have been able to ascertain the existence of fragments of entrail and bladder adhering to the inside of several carcases. * In England all transhipment work is suspended, when it rains or when there is a dense fog. The refrigerated and frozen meat is taken to the London Docks and carried to the ware- houses by barges, to the Markets, (in special wagons) or into the provinces (by railway). *) In 1906, during the Russo-Japanese War, Armour & Co. delivered 800.000 kilogramm of refrigerated beef to Vladivostock, The transport took 52 days. (American United States imports tend to diminish.). *) S. S. Malathan left Brisbane Sep. 3, 1909 (Australia) with a cargo of 1,331 quarters of refrigerated beef weighing 111 tons, and arrived in London on the 2nd of November, that is to say after a voyage of 62 days. According to Mr. Linley the meat in question had been 10 days in the cold rºoms at Brisbane, and in London the quarters could be preserved 326 In the Linley process as at present employed on board five great ships (S. S. Guàrdiana, La Blanca, El Argentine Manchester City etc.) the procedure is as follows : a) The meat, after slaughter is put to cool in the dry atmosphere of a refrigerated warehouse; it is there exposed to formaldehyde vapour in such a way as to sterilise the surface of the meat, and the visible fat, with- out, however, allowing of the penetration of appreciable quantities of formaldehyde into the meat. In general, say the inventors, ten days after this treatment it becomes impossible to detect formaldehyde in the meat; b) After this treatment the meat, provided with sterilised coverings, is let down into the cold holds, where the quarters are hung so as to avoid piling up, which is detrimental to good preservation. The air of the hold was fumigated previously with a certain quantity of formaldehyde, to pre- vent mildew and bacteria. The atmosphere is kept thus permeated only for a short time after the stowage of the meat. A system of fans allows of expelling the fumigating air and substituting dry air (by the use of "Ca. Cls) purified by bubbling through a sulphuric acid bath. As soon as the fumigating air is expelled, this apparatus is stopped and the meat is preser- ved in cold rooms which are unventilated. The Linley plants allow of the air in the refrigerated holds being so treated as to have a constant tempe- rature throughout. We have visited the Linley plant installed on board the ,Guardiana"; it appeared to us simple and easy of manipulation. * There were stored up in the ,,Guardiana" at the time of our visit 5,793 quarters of refrigerated beef, and the state of preservation was per- fect. The cattle had been killed ar Buenos Ayres in the week from the 17th to the 26” of November, that is to say one month beforehand. The meat had been preserved in the cold rooms of the Meat Company in Buenos Ayres two days. The x Guardiana's made the passage from Buenos Ayres to London in about 27 days *). It follows from this that the meat inspected had been preserved for about 32 days. 21 days in cold rooms, sterilised by the Linley process. The preservation of the refrigerated meat had then lasted 93 days with two transhipments. The meat was passed as in a good state of preservation by the Government Health Officers at Brisbane, by the Medical Officer at the dock, and by the market inspector at London. 700 quarters were sold at Smithfield Market 2 days after unloading. 100 quarters were sent to Liverpool, and 20 others to Wales. The rest were sold during the 3 or 4 days following their unloading. It should be noticed that not one company wished to undertake the responsibility of insurance. The Queensland Government had covered the cargo in case of failure. The voyage was very slow because the Marathon was obliged to make the whole coast of South Australia, and to call at the Ar- gentine Republic, before sailing for London. ) The freight charge per ton from Buenos Ayres to London, which is £ 5,100 for refri- gerated meat is £ 4.100 for frozen meat. * Thanks to the combined use of formaldehyde and cold in the Linley process, it has been possible to import into London already about 180.000 quarters of beef, and put upon the market goods which are almost without fault as saleable produce. A 327 Meat refrigerated by the Linley process is freely admitted to the English market. The Linley firm bring forward a certificate by Mr. Hurt- ley, professor of applied chemistry in London, tending to prove that formal- dehyd does not continue to exist in meat, a certain time after treatment. - We were able to make a report in France on a piece of sirloin pro- vided by Argentine beef unloaded at London after a 27 days 'sea voyage, 21 days preservation in Buenos Aires in the cold rooms of the exporting company, and 14 days of preservation in cold storage at Thames docks (a total of 62 days). When eaten either roasted or as a stew, the meat proved irreproachable in its effects. One single thing was perhaps noticeable, the fat covering it seemed changed in composition in such a way that it gave on cooking a slight taste of Suet. As a matter of fact this change is very superficial. The state of preservation of this refrigerated meat, previously sterilised by formaldehyde, is still perfect even five days after leaving the refrigerated hold. We have made certain of this. On the contrary the fat which surrounds the kidneys, decomposes quickly. In 3 days it gives forth a disagreeable odour. As to the nutritive value of meat preserved by a combination of formaldehyde and cold, some exceptions must be made. Formaldehyde forms indigestible compounds with albuminous substances. If the treatment is very strong, the antiseptic penetrates the Surface of the meat and may render it dangerous. Wiley') reports that milk preserved with formaldehyde is, injurious to the health of those who drink it (from an experiment carried out on 12 persons). Schryver *) and Buchanan *) do not hesitate to condemn the use of formaldehyde"). These are the conclusions drawn from the work entrusted to them by the Local Government Board of London: Schryver The Linley process has another commercial advantage; the losses by evaporation in the meat during the voyage are very slight. One pound to one and one half pounds per quarter are reckoned on from Buenos Ayres to London in the case of refrigerated meat, instead of two and a half pounds as is the case with frozen meat. The price of refrigerated meat is higher than that of frozen meat, but it is much less than that of English meat on sale in London. One may, however, question whetheer this method of sterilization and preservation is with- out detriment to health. This question has occupied the attention of the British Government. Recently the Local . Government Board on Public Health and Medical Subjects published the reports of Dr. Buchanan and Dr. Schryver who have enquired into this hygienic question. *) Bulletin of the Bureau of Chemistry, Washington, Bull. 84. *) Schryver, researches upon the impregnation of meat by formaldehyde. Reports to the Local Government Board by Dr. G. S. Buchanan and Dr. S. B. Schryver, on the Application of Formaldehyde to Meat, July 28th 1909 pages 5 to 12. *) Dr. Buchanan, Report upon the conditions giving rise to enquiry about méat preser ved by cold and formaldehyde vapours. Reports to the Local Government Board by Dr. G. S. Buchanan and Dr. S. B. Schryver on the application of formaldehyde to meat. Jull 28 th 1909 pages 1 to 5. - - 3. 4) Formaldehyde is employed in a proportion of 10 grs, per cubic metre of air, 328 examined beef (chilled meat) produced in the Argentine Republic, for for- maldehyde. This meat had been preserved for 53 days at 14° below zero C (29.5°F), fumigated on departure, and en route at Teneriffe. Cuts were made parallel to the surface, in order to ascertain how much the formal- dehyde had penetrated. In the surface fat were found considerable quantities of formaldehyde. The muscular tissue in the neighbourhood of the adipose tissue contained formaldehyde (1 part in 30,000) to a depth of 15 mm. The muscular tissue, protected by the fat contained less (1, part in 35.000 in the first cut underneath. The muscular tissue not protected by fat, (shoulder) contained 1 part of formaldehyde in 3,500 in the first cut 5 mm deep, 1 part in 10,000 in the part underneath this. .* The method of cooking the meat has some influence upon the results of its analysis. If the meat is grilled, the formaldehyde partially disappears, and part penetrates deeper into the meat. After boiling, the meat in cleansed of the larger part (9 tenths) of the formaldehyde which it contains. In roast ribs the formaldehyde cannot be any longer detected. In sausages formal- dehyde can be discovered. -- Summing up, fumigated and refrigerated meat, produced in the Argen- tine Republic, may contain formaldehyde to a depth of 2 centimetres. The proportion of formaldehyde may reach 1 part in 3.500. Buchanan declares that the use of formaldehyde vapour, a powerful disinfectant, is justified when it is necessary to cleanse the places in which the meat is to be preserved. He adds that it should not be forgotten that formaldehyde hinders digestion when it is present in food, even in a diluted state. The formaldehyde enters into combination with protoids and gives rather indigestible products. This point of view justifies the decision of the departmental Committee on Preservatives and Colouring Matter in foods, which was given in 1901, absolutely prohibiting the use of formaldehyde in preparations intended for eating or drinking. - One may say that all foodstuffs (meat, fish, etc.), exposed to fumigation by formaldehyde, absorb relatively large quantities of this disinfectant. Conclusion. 1. Frozen and Chilled Meat has a nutritive value equal, if not superior to fresh meat. 2. It is more digestible by virtue of the maturing which it has undergone. 3. It is particularly useful for victualling an army, a navy, large indu- strial centres, and in general administrations having a large staff. 4. Refrigerated and fumigated meat may be transported over long distances; it is very appetising; it should be examined to see if it is hurtful to health, when it is continuously consumed for a long time. \ 329 A Comparison of the Respective Values of frozen and chilled meats, from the point of view of general proviz sioning and more especially of provisioning of the army and large *. bodies. By Dr. H, Viry, Médecin Major de 2me Classe. Chief of the service of the 11th Cuirassier Regiment. One of the most interesting applications of the refrigeration of meat, is in the use of this meat for the provisioning of large bodies, armies, public administrations, hospitals, etc. But which of the two processes in the best ? Chilled meat or frozen meat? This is a problem requiring solution as much in theory as in practice. -- But the two processes each have their special advantages, and hence their special applications. They must each be perfected, and it must not be sought to make one take the place of another. This conclusion will become evident, we trust, when we have briefly described the properties of each of the two kinds of refrigerated meat, frozen meat and chilled meat. I. Definition and Properties of frozen meat. Frozen meat is meat which has been made hard in cold and dry air like a block of ice, by the freezing of the water which it contains. The temperature of the centres of the pieces of meat is brought down to, and maintained at — 4°C. Freezing is effected by a constantly decreasing temperature in the rooms, finally maintained at about — 8°C. Under these conditions the practical commercial time of preservation of the meat is 6 months. (National Refrigeration Congress, Lyons 1909). This period could really be prolonged, but without offering any apparent advantage. There seems besides, a risk of the meat deteriorating under the influence of chemical action such as the formation of 'gras de cadavre, (Dr. A. Gauthier). - The characteristics of frozen meat are then physical changes, it becomes a block of ice, which has stored up within itself a very perceptible 330 amount of cold, because it is at — 4°C in the centre, and at —8°C on the surface. It is unnecessary to remark that the composition of meat is not changed chemically (A. Gauthier) or histologically (Miss Pennington, Sir Rideal at the first International Congress of Refrigeration at Paris). Moreover it is well known that freezing is allowed in the laboratories preserving the pieces intended for histological research, Lastly Bordas, Lortat-Jacob, and Sabéreann in France, have shown that freezing does not affect the properties of the most delicate tissues and glands, and that these and their extracts preserve, or rather regain their properties on coming back to the ordinary temperature. From a scientific point of view, then frozen meat is absolutely equal to fresh meat; that is to say, from the points of view of chemistry, histo- logy, physiology, biology, nutrition, and degestion. As for its practical value, from a commercial and culinary point of view, it is enough to consider the present importance of the frozen meat trade, and the rapidity of its enormous progress, to realize the value of this product. We may, then, from a hygienic point of view, consider frozen meat as equal to fresh meat. What are its special advantages * ... " 1. The length of time for which it may be préserved (6 months). 2. The facility with which it can be transported. We have already spoken of the time of preservation. The time of 6 months has been fixed upon as the x commercial limit for good preser- vation. This time is sufficient practically, in commerce, and in the different cases in which meat must be stored and preserved. We will admit this then, and say: that frozen meat can be preserved with entire safety for 6 months; no appreciable change takes place except a little drying, amounting to a loss of 5 to 6% of its weight, by elimination of water, which is of no im- portance from a hygienic point of view. The facility of transportation of frozen meat may be placed under two essentially different headings: A. Transportation in a cold chamber may, theoretically at least, last as long as its preservation in a store. - In practice this has only succeeded in refrigerated ships, which are veritable storehouses, and in refrigerated trains which also produce the constant amount of cold necessary, forming travelling stores. Commercially speaking these trains seem at present, to be of very limited use, and to yield somewhat small profits financially. Their use in Europe can hardly be conceived, considering the small length of the journeys, except perhaps for the revictualling of armies. In Refrigerated Wagons in which the tempetature is kept below 0°C, or in the neighbourhood of 0°C, frozen meat can, thanks to the cold stored up in it, be carried for a very considerable time, depending above 331 -- all on the amount or cold stored up at the departure, or renewed en route. - The resistance of the meat during its transportation may be said to last for 10 days. This approximation is sufficient for our purpose. B. Transportation in bulk is made, in the case of frozen meat, with a facility which constitutes one of the principal advantage of this product. To confine ourselves to France only, the methodical study undertaken by the War Ministry in 1895 has shown the frozen meat may be trans- ported in the loose state. These experiments were made at exterior temperature reaching as much as 15° C. In an ordinary cart the journey can last four days with an insulation of straw and 6 days with an insulation of peat. The meat can then wait for 48 hours in a storeroom ai +12° C. Moreover, the time of transportation can be increased by 4 to 6 days, by allowing the meat to stay in a freezing chamber and refrigerating the Wagons (Review of the Military Commissary Service). The precautions to be taken are: an insulation from heat as effective as possible by covering the pieces with straw or better still with peat, and if possible, by providing the walls and top of the vehicle with coverings of straw or double walls. - Nevertheless journeys of 2 to 4 days can be accomplished by packing the meat loosely, the pieces being hung up and separated from each other. The cold stored up in the meat, is sufficient for its preservation. It should then be consumed within 24 hours. There is one objection made to frozen meat, that is the appearance on its surface of a mouldiness which is usual at low temperatures, and which may give it a sulphurous odour. The majority of companies making use of freezing, have taken the precaution of wrapping the quarters of meat in cotton sacks. * This very advantageous measure, greatly facilitates handling, the clean- liness of which it assures, and at the same time increase the protection against heat, and extends the time for which it may be transported in good condition. II. Definition and Properties of Chilled meat. Meat is said to be chilled when it has been submitted to a tempera- ture of about 0° C. According to the company, and especially to the local conditions, this temperature varies from +3° C to —29 C. It is never suf- ficient to cause freezing, even on the surface of meat preserved for times up to 3 weeks. (National Congress of Refrigeration Lyons 1909.) This meat preserves all its physical characteristics, appearance, colour, and consistency. It obviously keeps its chemical and nutritive properties, which are not even changed at considerably lower temperatures, as we have just seen. 332 A slight drying effect is produced due to the renewal of the dry air in the rooms of the store, but this is so slight that it has practically no im- portance from a commercial and hygienic point of view. But at this temperature the chemical action of the diatase contained in the meat is not completely prevented. It goes on according to a curve which ascends rapidly during the first 48 hours and then comes back again nearly to 0, without, however absolutely vanishing. This action is the same as that which takes place in free air in the maturing of fresh meat. It is then active in chilled meat. Above all, if it is remembered that this matu- ring is almost indispensable in insuring the digestibility of meat, it is ab- solutely necessary from a commercial point of view for bringing out the savour and tenderness of meat. Since this maturing due to the meat being placed in cold and dry rooms, takes place under protection from all the influences which, ordinarily, are likely to cause changes to take place in meat, it should be considered that chilled meat has two advantages over fresh meat. 1. The Commercial advantages, that is to say the certainly of not suffering any loss by bad trade, and of preserving, until it can be sold, any meat which cannot be disposed of on the same day. 2. The hygienic advantage of obtaining meat which does not contain any abnormal products of fermentation, and which is yet well matured. * In fact, if it is remembered that the practice ot refrigeration has brought merchants to consider absolute cleanliness, as well as the almost surgical asceptic condition of the places where slaughter is carried out, and of the persons who have to handle the meat, as indispensable to the luc- rative carrying on of their business, one may conclude, without hesitation that the employment of refrigeration in abattoirs constitutes a great impro- vement in hygienic conditions. - This improvement is yet more marked from the consumers point of view, being a guarantee of the good quality of the meat. We know, in fact, from the opinions of these merchants, that refrigeration cannot be allow- ed with meat provided by animals in bad health or feverish, or which are worn out or injured. The temperature of cold rooms is not sufficient to entirely prevent the diastasic fermentation of meat. This fermentation turns unhealthy meat to a clear red, soft and brown in 48 hours. We will observe, in passing, that the same effects are produced under the same conditions on frozen meat, which is only frozen very slowly, after maturing in the sweating and transition rooms, and hence it possesses the same hygienic qualities. Thus, refrigeration produces, on the whole, fresh matured meat, cer- tain in its hygienic qualities and in its commercial value, of perfect digesti- bility and having developed to the full its qualities of taste, flavour and tenderness. This meat may be preserved intact for 3 weeks; at the end of this time the diastasic fermentations which have not completely stopped, com- 333 mence to change the character of the meat, and, without making it une- atable, they diminish its commercial value so much that customers will not accept it.c. This figure of 3 weeks, which varies a little, according to the animals, is an average estimation. Moreover this period is, sufficient to en- sure full use being made of refrigeration. * * Attemps have been made to extend this period by various processes, the best of which is the use of formaldehyde. Formaldehyde produces a perfect aseptic condition in the rooms, on the surface of the meat itself, and in the air, at the same time producing a slight drying effect on the surface, which is very advantageous; it, however, disappears gradually by soaking up the water contained in the inside tissues. In the same way the peculiar odour of this substance entirely disappears. This process, which was . tried several years ago in the French Army by Medicin Inspecteur General Vaillard, has not met with any success in France where they are very particular as to using antiseptics in food. It has been taken up again, the process having been made considerably more perfect, consisting in fumi- gating the rooms with formaldehyde before the entry of the meat, and, if necessary, during storage, but a long time before putting it on sale. This method, ensured by the skill brought to bear on it, seems to give excellent results. Long transportations by sea have been accomplished with complete success, and the meat has been consumed in England without apprehension and without harm. Perhaps there is progress to be made in this direction, but we must be content with mentioning it, and leave a question whose study is outside the scope of this work, that of the part played by anti- Septics in the preservation of foodstuffs. - Returning to meat which is simply chilled, we would remark that the transportation of this, although not so easy at that of frozen meat, is, however, easier than that of fresh meat. Containing also, a certain amount of stored up cold, it can be trans- ported in package. It can even be carried in cold insulated wagons for 2 or 3 days, and also in refrigerated trains. Finally, it can be carried in carts, for 24 to 48 hours in straw or peat or loose, suspended from the walls of the vehicles, and protected somewhat from external heat. III. The use of refrigerated meat for the army. - From the special properties of frozen and chilled meats, we can now easily understand their use in armies or other large bodies, by considering the requirements of this special kind of consumer. - The army, in time of peace, is from a hygienic point of view, a col- lection of men just like any other. But we must note the contents of the following paragraph. . It is in time of war that it has other requirements. It is then, the revictualling of troops on campaign, to which we must give our attention. 334 What are the requirements of any army on campaign from this point of view P - The following are necessary to such an army 1. Healthy meat, that is to say meat provided by healthy animals killed under good hygienic conditions; it must also be matured and fresh. 2. An enormous reserve of meat to insure the proper feeding of the troops and of populations under siege, in which case it would have to be preserved for a long time. * 3. Meat which can be brought to the assembled troops, quickly and in large quantities, and in such a form that, if it cannot all be used the Same day, part of it can be used later on. * 4. Meat which does not give rise to difficulties of transportation from a strategical point of view. 5. Meat which does not give any risk of infection from a hygienic point of view. - We will study these five points one after the other, for each kind of provision; fresh meat, chilled meat, and frozen meat. y Fresh meat means herds, and herds imply. 1. Distemper, hurried slaughter, often of unhealthy animals, meat which is sometimes too fresh, and sometimes too stale, and always uncertain in necessary qualities. - 2. Reserve herds need sheds, fields and fodder, and involve a risk of more or less total loss of provisions in case of sickness. 3. The transportation of herds on the march is very complicated and slow. 4 kilometres per hour is an outside estimate, and must tire the ani- mals, and meat thus obtained must be killed in a perspiring condition, and cut up before being given to the regiments. There is great danger of loss in slaughtering them, as well as a risk of not killing enough. We must also consider the staff, material and space which in necessary. . Transportation by rail, which would not always bring the herds, is not possible with assembled armies who have none too many trains to carry the men, the munitions of war and food, and to carry back the wounded. 4. Cattle trains have to be stopped for the feeding of the animals, and hence fodder stations are required. They complicate and hinder the strategic trains. Further on we will compare their working with that of refrigerated trains. . 5. Lastly, the herds, by distemper, by the dirt which they make while travelling, and especially when confined; the slaughteries by the enormous amounts of useless waste matter, (hides, offal etc.) which they produce near the army on campaign, are powerful and permanent sources of infection and danger to the troops. All this, we repeat, without furnishing healthy meat in sufficient quantity. 335 Chilled meat has numerous advantages over herds for revictualling troops, but is does not always fulfil all the necessary conditions. 1. It provides fresh, healthy meat, killed at a distance from the army. 2. It provides a reserve which however cannot last more than three weeks, and hence cannot serve for long provisioning. 3. It can easily be carried to the vicinity of the troops in one or two days, but, except in rare cases where refrigerated trains are used, meat not immediately consumed cannot be relied upon to be used later on. 4. It does not give rise to difficulties of transportation being trans- ported in the same may, as we shall see, for frozen meat. It does away with the necessity of providing fodder for animals near the troops. 5. It does not give rise to any danger of infection, because all that is brought in by the conveyances can be entirely used by the troops. We may conclude then, that chilled meat provides good healthy food for troops on campaign, and does away with all the hygienic dangers and strategic inconveniences of herds. But it can only be used for certain cases, never for besieged places, which require provision for a long time, or for camping troops, but only for furnishing meat to troops on long marches, when they are in the neighbourhood of railways, and free from the sudden variations and eventualities in the journey which are created by the imme- diate proxmity of the enemy. Moreover, chilled meat would be useful for revictualling the troops bringing up in the rear, whose provisions and rations are arranged for in advance, and which can be provided directly by the slaughter houses situ- ated throughout the country. Lastly, frozen meat has all the qualities required in a meat to be used in War. 1. It is provided by healthy animals, killed under normal conditions near their breeding places, by suitable people and in suitable places. 2. The length of time for which it may be preserved (6 months) admits of providing large stores of food in a relatively limited space so as to furnish the amounts required by populations and garrisons under siege and by neighbouring troops. - 3. It is carried to the troops by refrigerated trains or by goods wagons; it can also be carried by carts, and what cannot be immediately used may be preserved, only requiring a few simple precautions. 4. It allows the herds which hinder the marching of the troops to be dispensed with. Thus, according to the veterinaire militaire Marchal (mili- tary veterinary surgeon) a batch of 100,000 rations would amount, in live animals to 222 to 333 oxen or to 2,200 sheep. For frozen meat carried in 2 horse "military wagons these 100,000 rations would occupy 40 wagons taking up 320 metres of the road. Of course it does away with the need of forage. 336 Lastly, on the railway this would occupy the smallest possible Space, because it can be piled up as any other merchandise. According to the same authority, to carry these 100,000 rations as live animals requires 28 wagons for bullocks, 33 for cows, 44 for sheep. For frozen meat 4 ordi- nary wagons are required, or 3 refrigerated wagons on B. Durants system. As to the rapidity of the journey, 30 kilometres per day is reckoned for herds, 4 kilometres per hour for carts; and 25 to 45 kilometres per hour for carts; and 25 to 45 kilometres per hour for trains. ** 5. Lastly, this method of revictualling does away with all the dangers to the troops involved by herds with their sickness and dirt, and by slaughteries with their waste. Summing up, we will repeat, with all the authorities who have been engaged on this question for 30 years, that frozen meat is necesaary in war, and indispensable to all modern armies. We would add that chilled meat can also be very useful for economizing the store of frozen meat, by replacing it by batches and from the centre of the territory whenever it can be made to arrive directly near the troops. **. IV. The use of refrigerated meat for garrisons and large bodies of men. War is, happily, only a possible eventuality and not a normal condition. Ordinarily, armies, as far as hygiene is concerned, are only large bodies similar to any group of consumers. In the question with which we are now concerned, we can study the comparative values of chilled and frozen meat for the army and for civil bodies in the same chapter. We will note, then, what qualities are required by such bodies, of the meat provided for their consumption. 1. Meat provided by healthy animals, killed while in a good condition of nutrition and digestion, prepared in a clean slaughtery, preserved up to delivery in a place sheltering it from putrefaction germs and atmospheric variations. - 2. A guarantee to buyers of the quality of the meat. In armies, there are organised services attending to the supply of meat. In France these have recently been made more perfect. - The animals are inspected and marked by the army veterinary surge– ons and doctors. They are inspected after slaughter and each piece is marked. These are accompanied from the slaughteries to the army meat stores by subordinates who carry the parts of the quarters selected so as to make sure of their identification on arrival. They are examined here by the distributing officer, the doctor and the veterinary surgeon. Lastly, at any time, even after receiving the selections, pieces are again taken and analysed by the regimental doctor. Similar measures are difficult of realization for civil bodies, who have not the necessary staff. Nervetheless some kind of sanitary control does exist. 337 Will refrigerated meat fulfil these requirements? Whether it is frozen or chilled, it has the same guarantees of health- iness and cleanliness. As a matter of fact we have already seen that unhealthy or bruised meat deteriorates in cold rooms. Merchants are obliged then, in their own interests to accept healthy meat only. This is an automatic guarantee for dustomers. We have also seen that cleanliness in slaughtering and handling, as well as the cleanliness of the abattoirs and cold stores is indispensable to the lucrative working of this industry. The consumer, then, has an absolute guarantee against contamination or uncleanliness of any kind. As for any sudden changes in the atmosphere, or bad, sour or stringy meat etc., the principle of preservation by cold is directly opposed to these and the success of this process has proved its value. Thus, refrigeration furnished the army and other bodies, as well as in- dividuals, with meat of a quality, and with a guarantee, which the most conscientious butcher cannot give, who is never quite sure of his suppliers and has no control over the temperature. Is it necessary to choose between chilling and freezing The special 'conditions of each country should settle the question. When it is neces- sary, as is the case in England to rely on imports, freezing only seems to give the desired results, up to the present. As for the future, the answer lies with the merchants and not with the hygienists. When, as is the case in France, home production suffices for home consumption, chilling is enough, because it is only required to preserve the fresh meat from the time of slaughter until it can be sold. On the other hand chilled meat has the advantage of not necessitating the thawing to which frozen meat is subjected, and which requires an amount of care. It has, moreover, the great advantage of not differing even a little from fresh meat. These are commercial and not hygienic questions. But the introduction of cold in the meat industry has brought about enormous progress, which is of great interest to the hygienist. From his point of view alone it is enough to encourage refrigeration. This is what M. de Loverdo calls »the industrialization of the meat trade.<. It is possible to effect modifications which are very advantageous from a hygienic point of view, by means of cold in preserving perishable food, stuffs such as meat, until consumption. 1. By removing the causes of deterioration in meat, cold gives a gua- rantee to the consumer of the quality and healthiness of the product; and its effect on the maturing action, increases its hygienic valuc. 2. By allowing slaughtering centres to be etablished near the centres of production, from whence the meat can then be despatched to the cen- tres of consumption, cold allows of the animals being killed under the best conditions, when they are best prepared, and without tiring them out at the last moment. 22 .338 3. By regularizing the meat trade, it lowers the price which for the •ordinary or poor populations, amounts to an increase in nourishment, that is to say in hygienic benefits. … We need not enter into the economic consideration of the results ot this progress, so we will limit ourselves to concluding thus: i 1. Frozen meat is necessary for transportation over long distances and for provision in time of war. 2. Chilled meat is the best for the constant consumption of countries which consume their own products or those of neighbouring countries. 3. The use of cold should make progress in all countries which give any attention to the hygiene of foodstuffs, because of the guarantee which it gives to the consumer, and the improvement which it effects in the meat industry itself, as well as in the product of this industry; and refrigerated meat should be used in preference to all other in the army and in large civil bodies. 339. Investigations on the Preservation of Horse- flesh by Means of Cold, and the Use of this Flesh for Food. By Dr. Alexander Costa and Dr. Nello Mori, Veterinary Officers in the Royal Italian Army. The experiments conducted by us on the preservation of horse-flesh and on its use as food might appear valueless to those who through pre- judice are opposed to horse-flesh as food. We hope that in spite of this they will be of interest to those who know how great an influence nourish- ment has upon the popular welfare and that these will see in our work a contribution, though it be but a modest one, to the progress of modern , social institutions. To confine the extent of future applications within narrower limits, however, we are of the opinion that these experiments might serve, under certain exceptional circumstances, to partially solve the important and diffi- cult problem of provisioning troops in the field. Several experiments have already been actually made with fresh horse- flesh in this direction; but so far as we know, no one has thought of making use, with the aid of refrigeration, of the flesh of those horses which become suddenly useless in war, and which always offer the greatest hygienic and Sanitary guarantees. Whether the horse be killed suddenly by shot or thrust or die later as the result of wounds, or whether a longer period elapses between wounding and death, it is yet certain that many quadrupeds perishing in this manner would afford good meat, that under certain conditions would be suitable for Satisfying the most urgent food requirements of troops. A well-organised flesh utilisation service, to convey the flesh in fast travelling refrigerated conveyances to the cold-storage depôts and from these to the points of distribution, would evidently offer an important economical source of supply which must not be undervalued. It must also be borne in mind that when such service is established, another exceedingly hygienic purpose is attained, namely, the clearing of O. ::: 340 the field of a certain number of horse cadavers as quickly as possible, and consequent decrease of the dangers resulting from decomposition, especially when the tedious and difficult task of burying and destroying the dead bodies of the horses cannot be effected with the requisite speed. Plan of the Experiments. The experiments which form the subject of the present paper were mostly carried out in the cold installations of the town Monza, which were. placed at our disposal in the most amiable manner by the head of the municipality. Experiments were carried out: a) on horses in normal physiological condition slaughtered normally after suitable rest; w --- à) on horses slaughtered normally when in tired condition; c) on horses that died from or were killed by chance wounds, and were prepared (bled, and dressed) some hours later. * During the experiments that were conducted in the course of the past Summer exact observations were taken daily of the temperature and dampness of the rooms in which the meat was preserved the registering thermometer and the quadrant hygrometer of Richard being used. - It was thus ascertained that the temperature in the rooms fluctuated between 19 C. and 40 C. The moisture amounted to between 60° and 70° C. Horses in normal physiological condition slaughtered normally after suitable rest. The horses made use of in these trials were bought on the market and, after strict sanitary examination, knocked, bled, dressed and split in the skin or quartered after skinning. After completion of this work the meat was left for 24 hours in the ante-room of the refrigerator and only after this placed in the refrigerator. Another time, to test less favorable conditions the meat was immediately placed in the refrigerator. A. In both instances the results, briefly given here, were almost identical, at all events during the period of these trials. - Period of preservation. 1. The flesh of horses of normal physiological condition which was left in the skin and kept the whole time in the cold cells was found to be in perfect condition after a lapse of two months, and would certainly have. kept still longer if the trials had been extended. 2. The above mentioned flesh was withdrawn from the action of the cold every five days and kept for 24 hours at ordinary air temperature, and in this case it kept good for between 20 and 30 days. 341 3. The quartered and skinned meat which was kept in the cold cells the whole time, kept good, as did that in the skin, for two months. 4. The quartered and skinned meat which was treated as in No. 2 kept good for 15 to 20 days. 5. Meat cut into small pieces kept at most 24–30 days. 6. The soft parts of the hollow of the breast which were kept the whole time in the cold cells kept good from 20 to 30 days; in this period, however, the heart assumed an unsightly appearance. 7. Of the viscus the liver did not keep . good more than 8–10 days, then it turned pitch black and became unsightly, and a few hours after removal from the cold cells it decayed. The kidneys, left in their place, kept for about 20 days. 8. The brain, if left in the skull kept perfectly good during two months; if taken out of the skull and placed in the cold cell it kept for one week at longest. Changes in Weight. The experiments on change of weight of horse-flesh during preser- vation were extended to quarters of horse-flesh and mules, which were weighed before being placed in the ante-room of the refrigeration works, and again every second day so long as they were kept in the cold rooms. It was proved by these repeated measurements that during 30 days of preservation the meat suffered a loss of from 8–10%. The properties of chilled Horse-flesh. The deep red colour of fresh horse-flesh remains, in cold, during 10–15 days, then it gets gradually darker on the surface until after two months it often becomes almost black. The flesh of the fore quarters, however, darkens on the surface in the cold room after a very short period of time. The smell of the flesh experimented on did not differ from that of the fresh meat. The consistency remains normal for a long time. After about 15 days storage in cold rooms the cut surfaces appear brighter than those of the fresh meat. -- Chilled horse-flesh becomes tender after 10–45 days. This naturally depends on the kind of animal, the race, age, and the amount of work done by the animal. After but 10 days storage in the cold room the meat cooks much more quickly than does fresh meat, and requires about the same time as is necessary for cooking the unchilled beef of 5–7 year old animals. As regards the quality of horse-flesh we limit ourselves to the assurance that it has been tried after various periods of preservation, boiled, roasted and sodden, by ourselves and by our colleagues and by officers of the of *s, 342 ficers mess and was ever found to be tender, appetizing and of agreeable taste, similar to that of the turkey. ; Soup made from such meat is also found to be of agreeable flavour,. similar to that of chicken broth. Horses in tired condition normally slaughtered. Three horses served for these trials; namely: The foal of a troop mare which was driven in the usual manner to the San Giovanni market at Monza and arrived in tired condition; A horse which ran away from its owner in Milan and after about four hours' pursuit fell and broke a leg, and on account of the injury was taken from Milan in a cart to Monza and there immediately killed; A second horse, that also escaped from its driver and fell after some hours' unguided running, was killed because it was severely injured in the fall. - These animals were killed with the mallet immediately on arrival, and were bled and dressed on the spot. Their flesh was of a darker shade than that of the rested animals, and further it had a piquant but not objectionable smell. The flesh was at first left in the ante room of the refrigeration works for 24 hours, and then it was placed in the special refrigerator. ...~ Period of Preservation. The period of successful preservation of this flesh as was to be foreseen, although left in the skin, was considerably shorter than for the flesh of sufficiently rested animals. On an average it did not keep for more than 20–30 days. Indeed the flesh of the last animal showed signs of decay after but 15 days' sto- rage in the cold cell. The entire flesh decayed in a few hours after removal from the cold TOOII]. --- Properties of the meat. The colour of the outer surface of this meat began to darken after 4–5 days’ preservation and it became quite dark after about 15 days. The smell, fairly strong at first, almost completely disappeared after a few days' cooling. $ sº The consistency of the meat decreased after a few days and the cut meat became soft of itself. On the cut surface the meat showed almost the same colour during the whole period of preservation in the cool-room, as it had in the fresh state. While for comparison the cut surface of meat from rested animals that was preserved by refrigeration exhibited a brighter colour than when fresh, as has already been stated. 343 This group of meats cooked much more quickly than that from rest- ‘ed animals. As there exists a difference of opinion among writers as to the harm- fulness of eating flesh of tired animals, one of us purposely, for several days in succession, ate of the meat that was under examination. He ex- perienced no inconvenience whatever, but only found the meat somewhat less tasty than that of rested animals. * Horses that perished or were killed by chance wounds, and which were prepared some hours later. Horses and mules that had perished through chance injuries were the subjects of these experiments, their blood being withdrawn after a lapse of from 2–3 hours; also horses that were killed with the mallet and were bled after such lapse of time and then were prepared in the normal manner.) We made no experiments with animals that had been shot, as we believed that the flesh of such animals would most probably not behave differently in cold to that of those killed with the mallet. In bleeding the above mentioned horses, after 2–3 hours, we were able to ascertain that the blood flowed from the opened veins just as it would from fresh killed animals. The viscera of both animals were also almost exactly the same as those of animals from which the blood had been withdrawn immediately after death. A slight congestion was noticeable in the peripheral arteries of the body and extremities. Period of Preservation. The keeping time by cold of, the meat of such animals as were treated in the above mentioned manner, varied according to the nature of the wound which caused death and the time that elapsed between death and transfer to the refrigerator. In every case the meat kept much longer than did that from tired horses; and some quarters of mules were found to be in perfect condition after 40 days’ storage. The p r operties of the horse - flesh of this group exhibited no notable differences from that of animals from which the blood was with- drawn immediately after death. Horse flesh first cooled and then cooked and again cold stored. The object of this experiment was to determine whether, and for what period the preservation of such meat could be expected if, after a shorter or longer time in the refrigerator, it was cooked and then again returned to the refrigerator. *) The animals, after slaughter and bleeding, were left in the abattoir corridors, lying -on the floor. 344 We purposely omitted to deal with the conservation of meat first cooked and then cooled, since the experimets of E m me t and G r in d 1 ey regarding boiled and roasted beef and game were known to us. On the other hand, it appeared to us that if the results with meat cooked after a period of cold storing were encouraging, then it could be expected that at least equal if not better results could be expected from meat that was first cooked and then cold stored. To this end two hind quarters of horse, one of which had been cold stored for 15 days and the other for 20 days, were cooked. • The cooking was done in a boiler which contained 200 litres of water and 3 kilos. of common salt. When the liquid began to boil the quarter was completely immersed, and in such a manner that it touched neither the bottom nor the walls of the boiler, so that the cooking might be effected evenly. After five hours cooking it could be seen that the inner muscle masses were not completely cooked, but yet the meat had a good appearance and was very juicy. In order to attain a complete cooking of the second quarter, vertical cuts were made in it before immersion, because of the specially voluminous. and deep muscle masses. This resulted in the meat being evenly cooked throughout. - After the cooking both quarters were hung in the slaughter-house at ordinary air temperature (in July) for 5–6 hours, and then they were taken back to the cold room. The meat of these quarters, periodically examined and tasted during its stay in the cold room, was still in perfect condition after a lapse of 35 days. Slightly dark and dry on the outside, it had a good appearance and a pleasant smell, and was especially similar to boiled beef in cut, and very tasty. C on clusions. From all our experiments on the preservation of horse-flesh by cold- we think we are justified in drawing the following conclusions: 1. That the flesh of horses in normal physiological condition slaugh- tered normally after suitable rest, whether skinned and quartered or left in the skin, will keep perfectly well for two months if subjected to a tempe- rature between 19 and 49 C., and an air moisture of 60° —70°. 2. That the flesh in the skin if withdrawn from the refrigerator every 5 days and left for 24 hours in ordinary temperature keeps in good condition for 20–30 days. If the carcass is skinned and quartered the preservation. would be 15–20 days. - 3. Meat cut into small pieces will not keep more than 25–30 days. 4. The flesh of such horses as are slaughtered when in a normal but tired tired condition will not keep in cold longer than 20–30 days, and often show signs of decomposition after but 15 days. - 345 5. That the flesh of those horses that perish from wounds or are killed on account of injuries, and are not bled, dressed etc. until 3 or 4 hours later keep well for 35–40 days. 6. That quarters of horse, that have been previously cooled 15–25 days, and then cooked and again cold-stored, keep in good condition for at least 30 days. Opinions and Pro p os a 1s. The above conclusions regarding the manner in which horseflesh behaves in cold, have confirmed our supposition that it is possible, under suitable conditions, to increase the consumption of horse-flesh among the poorer classes, and in case of war, to make use of Such meat in pro- visioning troops. Actually the normal preservation of such horse-flesh in cold rooms of public abattoirs, apart from enabling the meat to be kept for much longer times (and this is an economical saving that cannot be despised), and without deducting in any way from its nutritive value, lends the meat such properties that it may very easily become a welcome object to the public. As regards the eventual use of the mentioned meat as a food reserve for troops in war, limitation is necessary to those horses killed in battle or to such as are killed on account of their being too severely injured to be of any further service. The experiments we conducted regarding the flesh of horses in a state of exhaustion, which would be almost the same as that in which such animals would be in war, did actually show us that, although the flesh of exhausted animals offered less resistance to destructive processes and was less tasty than that of rested animals, yet it is still possible to make use of it in extreme cases for the nourishment of troops. Experts can at all times give their judgment on the hygienic and sanitary condition of horses proposed for nourishment and on the state. of the flesh of such horses. A difficulty that would doubtless arise in practice would be the sal- vaging of the horses killed in battle and their removal from the field. We made special experiments, which showed that under the most unfavourable conditions as to environment and wounds, the flesh of animals which were not bled and prepared until 3 or 4 hours after death was entirely usable and could be preserved for a long time. To facilitate making use of their flesh it would be necessary to remove the dead horses and prepare them as quickly as possible; in order to be able - to place the animals in cold ambulance wagons it would be necessary simply to divide them in the skin for transfer to reserve cold depôts or in cases of great urgency directly to the place of consumption. Dead horses left on the field for a long period must result in their Being rendered useless by decomposition. 346 It is unnecessary to add that to make use of horses, killed for pro- visioning purposes on account of severe injuries, must be governed by: veterinary regulations such as are in force at public slaughter-houses. We consider it desirous that we draw the attention of the authorities. to the results attained in the experiments with cooked and refrigerated meat. In our opinion the conveyance of cooked and chilled meat (be it beef or horse-flesh), by very rapid transport wagons, to the troops on the fighting line would form a source of assistance of great importance. * In consequence of the results of the experiments we have made, and which are summarised in this paper, we have the honour to submit the following proposal to the second International Congress of Refrigeration: I. Efforts should be made to extend and cheapen the use of horse-flesh. as nourishment among the less opulent classes, drawing assistance to this. end from lectures and publications and from the erection of refrigerating. plants in slaughter-houses which are not already provided therewith. II. The military authorities should arrange a special service, which should have as object the preservation by means of refrigeration of the flesh of horses killed or rendered unserviceable on the battle field, and the appli- cation of the same as a food reserve for the troops. III. It is proposed to place boiled meat in cold storage and therewith: replenish the exhausted supplies of troops during battle by shipping such meat in fast moving refrigerator wagons to the proper destination. Rome, 26th August 1910. •º 347 Cold Storages as Accumulators for the Provisioning of Armies in the Field. By H. Heiss, Director of the Abattoir at Straubing. In consideration of the enormous increase in the masses of troops of the great powers, the commissariat question must receive a far greater amount of attention than it does at the present day. It would indeed be the worst mistake an army commissariat could make, to rely on finding a sufficient supply of provisions for their troops in the districts occupied. Whilst in former wars the troops were made up of more or less disciplined mercenaries who were accustomed to live by plunder and robbery, and who :as raw warrior types were, if need be, also satisfied with the most modest nourishment, the armies, of modern states include the sons of all classes and professions of the land, and these powerful and highly trained bodies of troops can be set in motion to-day with uncanny rapidity and precision The means of conveyance of the present day make it possible that in an incredibly short space of time hundreds of thousands can hurry to the standards and that the forward march...to the seat of war can be conducted with equal rapidity. The fact that the troops are drawn from all grades of the population, from simple and from educated classes, makes the requirements of to-day other than those of years ago as regards provisioning. There is no doubt that the love of life and pleasure in all divisions of the people has grown regularly and very considerably increased; we even find that it is not always those circles that have the smallest income who are the most ‘unpretentious, and that especially the consumption of meat among the working classes has increased to a remarkable extent, corresponding to the increased demands on their working capacity. If in case of war one were prepared even to be content with just Satisfying the pangs of hunger in cases of exigency, if, further, with the best possible preparations it often and often happens that the supply of provisions fails at short notice, since unforeseen constellations can arise, yet every modern state will recognise the important duty, to-day, of fully considering in peace-time all the eventualities of a war, and of making great and most exhaustive use of times of peace to thoroughly and exhaustively examine and prove in every direction the possible and necessary ways of provisioning 348 with every kind of food, and thus collect experience that could be applied : without further trouble in the case of war. .* The higher the grade of civilisation of a people, the greater the consumption of meat, and statistics show that for example in the German Empire 50–60 kilogrames of meat are consumed per head of the population. If in time of peace the people of a country are not able to carry out their professions without meat consumption, here, at once, an under-feeding must be avoided in order that the effective work may not be reduced; the soldier then will be quite unable to fulfil the enormous demands made on his. effective working powers without regular meat provisioning. The consumption of meat must increase his powers of resistance and meat produces warmth and warmth is life. One must not claim that the Japanese fought great victories on a nourishment consisting of rice and dried shell fish, in spite of their great progress in culture. Even they were not able in the Manchurian battles to entirely do without meat. Man is a flesh-eater, and though the Hamals, the carriers of Constantinople, who are exclusively vegetarians, possess enormous bodily strength, though the powerful Asiatics. and the African peoples almost entirely suffice with vegetarian food, yet the first condition that such food shall be productive of strength is just that from youth on the body be accustomed thereto. A rash change from meat nourishment to vegetarian would show just as serious results as would the reWerSe. Our peasant folk, who eat but little meat during the week, incline now more and more to the consumtion of meat. Nourishment cannot and must not be exclusively of one kind if bodily strength is to be main- tained. To convey the meat food necessary for their nourishment, to the troops in the field, a system of driven herds are chosen which follow the troops at greater or lesser intervals and in better or worse quality. They are moved forward partly by rail and also to a great extent by road, and it cannot be wondered at if these herds, taken from their restful stalls, from their regular food and attention suddenly into other conditions of living, which do not afford them the necessary principal conditions, are decimated by sickness, slackness or even epidemics. The invariably failing order and control of the border service in time of war will make it possible that animals with pest be brought from neighbouring districts and forwarded, and thus it is easily explained that just in time of war the most dangerous. epidemics may be observed, that lung sickness and cattle plague in the latest wars have almost invariably been in evidence. Through these sicknesses the reserves of cattle on the land crossed by the troop transports are also severely affected and doubtless the endeavours of modern conduct of war must also be directed to preventing as far as possible such damage to . national wealth, for thereby the possibility of a Sure and regular provisioning. of the troops is also diminished. 349 Hitherto it was almost unavoidable that almost life warm meat should be handed to troops in the field, since the slaughtering had to be effected on the field, and that not only sick animals but also animals near their end, if no other flesh material was available, had to be supplied for the soldiers wants. Apart from the fact that even the best fresh killed meat is tough, the consumption of doubtful meat offers at least great dangers to health. And it is extremely pleasing to think that the many cases of typhoid that one invariably has opportunities of observing in wars are for for the most part not cases of typhoid in reality but states resulting from meat poisoning. The apparent epidemical spread of these diseases is ex- tremely well explained by the commonly harmful cause. War also produces an extremely broad conscience in most cattle purveyors. Nothing is so bad that it is not still good enough for the troops. At such times there are a number of black characters who in order to enrich themselves at Small pains play a wicked game with the lives of the Sons of their fatherland; yet not alone in war-time, at the manoeuvres of peace, also, such actions may be observed, as the army provisioning scandals discovered but a short time since in France have shown. Since such happenings occur even in peace time, how much more frequently then in war time when the possibilities of strict control are extremely often dimi- nished and deflected by other more important business. Do we not often remark, even in times of peace, with what craftiness cattle owners operate in Order to gain the highest possible profit from the sales of their animals. How much more, then, will they exercise their best endeavours to pass of good wares for bad to the state and will make use of the opportunity offered to earn as much as possible, they know full well that the state is compelled to buy at any price. Though we are well aware that future war will be more terrible than ever and that diplomacy seeks to hinder it at every price, yet some unforeseen accident may enflame the torch of war; then fortunate they who have in every way prepared for war during times of peace; and as the modern art of war must always keep pace with the latest progresses of every kind of technics; as, further, the arming, munition, and training que- stion of an army must play an important we must also consider the regu- lating of the provisioning question for the vast masses of troops in such a manner that, full of confidence we may say: We have done our duty in every respect! And just as the various nations seek to overtake one another with regard to the preparedness of their armies, so must they also, with regard to the technique of provisioning, which must be fully and entirely up-to-date. To-day recourse is had to fresh killed meat only in moments of the greatest necessity, that is to such meat as is obtained from driven herds. At all events then, only when slaughter animals are obtainable on the spot. The provisioning with meat conserves hitherto practised 350 will be resorted to solely for the sake of change. These conserves may be used with the utmost advantage as reserves, as they are not subject to decay, "otherwise, however, apart from the the not inconsiderable cost of production, they form a food which is in great favour among the troops. Beyond this it must be remembered, that almost half the total weight to be transported consists of packing alone, a circumstance which is not to the advantage of this kind of provisioning, but which unfor- tunately cannot be avoided. - If to-day every attention must be paid to mobility of troops, analogous demands must be put forward as regards the provisioning, and every unnecessary weight must be carefully avoided. Meat is indispensable as nourishment for troops. If, now, the meat is not to come from freshly killed meat, if driven herds (which on account of the possible spreading of disease form a great danger to the national wealth) are not to follow the troops, if the provisioning by means of meat conserves cannot suffice and cannot be considered free from objection, then it remains to find a method of meat transport which shall entirely satisfy present day requirements, and which is also able to inhibit the natural decomposition processes which this chief article of nourishment is subject to. It cannot, of course, be supposed that the various preserving processes, such as smoking, pickling, which are resorted to or possible in peace, could be applied in serious crises. Nor may we think that the somewhat chemical preserving process made use of in the last Russo-Japanese war, and kept strictly secret there, will come into general use. , For modern provisioning of troops only one process can attain to practical execution and that is preservation through cold! At the first international Cold Congress at Paris, the question was raised of making artificial cold serviceable for this purpose. This plays an important part in various industrial spheres, and in the sphere of meat preservation it has made enormous progress in the two last decades! We know that to the modern idea a slaughter house without cold plant is not considered up-to-date, and within the last five years, with but very few exceptions, no slaughter house has been erected without being provided with a cold storage plant. This invaluable addition must be present because it is considered to-day to be indispensable. It is not my task, nor indeed the suitable occasion, to lose even one word on the ways of producing cold, and it shall merely be mentioned that in the German Empire alone about 70 per cent. of all slaughter houses are provided with cold plants: Surely an eloquent proof of their practical value. º Though France be the real fatherland of the Cold Industry, yet at the time;-incredible though it be, this epoch-making invention met with but little understanding, and if they are now making every endeavour there to make up for lost time, yet that will not hinder the fact that other states are enormously, almost beyond reach, in advance as regards the introduction 351 of meat cold storages. Even though England, for instance, in the question of slaughter houses has hardly overcome the most modest beginnings, yet we find that that country, as regards the provisioning of the broad masses. of the people with frozen meat is far in advance of all other states. - It must from the first be pointed out here what difference exists. between meat preservation in a cold plant and in a refrigerating plant. The cold installations enable the previously chilled meat to be kept for a long period at a temperature ranging from 0° to 4°C., given sufficient ventilation, continuous change of air, and the requisite dryness of the air. They only have tº object of keeping unfrozen meat for such period as is necessary to effect its sale. Condition is: pre-cooling. He who rents such a cool cell is not anxious to preserve the meat for months; on an average two weeks are more than sufficient for his requirements. But he will demand that the meat is not only in perfectly good and fresh condition but also that it can be taken from the cold cell in such state that it can be at once, without further measures, placed on the market. It is, however, not unknown that the meat kept in cold rooms gradually becomes dearer, that loss in weight takes place, and for this reason alone a longer period of storing is avoided as far as possible, that, with all the advantages, it may not cause the seller loss. It is different with the freezing plant. The meat introduced will keep its weight and suffer no harm for an indefinite period of time, will not in the least degree lose in appearance, and yet will show all advantageous changes, such as ripening for instance. It will, however, require a longer time in ordinary temperature before it can be changed to a state fit for selling and for eating; and it has, through the freezing process, undergone changes in substance, which must first be negatived. For this reason it only occupies secondary place in the consideration of the retailer. It is just this circum- stance that falls with such great advantage into the scale in favour of the provisioning of troops with such meat. It shall be pointed out here how practical England has made use uſ this procedure. Unable with the cattle produced in the country to procure sufficient meat food for her great population she organised long ago a large over-sea meat import, which works admirably. It brings meat from New Zealand from La Plata, from North America in frozen state, by ships that have cold installations to England, where, at the London Docks, gigantic store houses have been erected for such meat, which, in the course of time, has become an indispensable article of popular food, and as regards flavour Satisfies the most fastidious palate. This receives especial mention because in many countries a natural, but more often artificially produced prejudice against frozen meat exists; more shall not be said of the ever equal instigating cause of this prejudice, but merely the fact registered. Extensive scientific trials have proved without the slightest objection, that no difference in the least exists between fresh and frozen meat as regards taste and nutritive qualities. And why? 352 - Fresh meat is placed in the freezing room immediately after the killing; there it stiffens to a hard mass and not being subjected to pre-cooling no loss in weight arises. The decomposition process, which generally begins within a few days is certainly stopped by the freezing. Every visitor to the beautiful island will remember with pleasure the tasty meat of the dinner-table, and will in silence wish that the beef and mutton he found there might also find their way to his country. That, however, which has been an admitted fact there for decades shall not and may not be doubted and disputed as improbable, in spite of better conviction, in another land. If the ordinary cold house of the slaughter house acts as accumulator between delivery and disposal, then especially the freezing plant, which serves this end to a high degree, since by it are guaranteed absolute security and durability, must form the solution of the question of the provisioning of troops. Let us make a comparison: Fresh meat spoils at latest in five days after the slaughtering; cooled meat can be kept for weeks and months, though the process causes loss in weight, if such meat is elsewhere immedia- tely saleable. Frozen meat, on the other hand, unites the certain preservation without loss of weight, and further also makes it possible that the time of transport to the place of consumption can be used to allow the slow, development of the thawing process which naturally results from the warmer Outside air, so that it arrives in a condition fit for immediate consumption, thawed, and yet able to be kept in good condition for a further three or four days, as the freezing process suddenly stopped the process of decomposition and the development of this process will only begin when the effect of the cold is nullified If we now consider the fact that the quarters of beef stored in the freezing houses of the great American firms at Chicago are taken, on call, in isolated waggons to New Orleans and arrive there fresh and ready for sale, the value of this system is thereby sufficiently proved. And the con- ditions, nearer to us, existing at the Smithfield market in London enable us daily to observe in how rational a manner over-seas frozen meat is removed from the cold store exatly as requirements demand, thawed and placed on the market. Indeed unsold goods are even re-frozen. To bring the system into practical use in other countries one must pay first attention to finding towns to which the meat can be delivered in frozen state and maintained in that state. Apart from the none too numerous freezing plants we possess, slaughter houses will be the first places to be adapted for the purpose. In many instances it will be possible by simply lengthening the hours of work, to produce temperatures of — 5" in the inner rooms and should this not be possible thep peace will have again to be made use of to fit out cold installations of every size in such a manner that without further trouble they may be used as freezing stores if required. 353 The fact that slaughter houses would then become the sources of meat supply for troops guarantees that the flesh comes from healthy animals and constitutes a food free of objection, for there the control is an abso- lutely reliable one Delivery of doubtful animals is, there, impossible. The control of epidemic and possibility of extirpation are absolutely ensured. Those frequenting such place would, for the first moment, find the freezing of the meat an unpleasant matter, yet obeying necessity, not their own ends, would submit to the inevitable so much the more because their goods suffer no loss, and the use only demands a slight change in the arrangement of time. It will also have to become one of the first tasks of the Army to procure military freezing installations, and here the English plants may serve as model. , - It need hardly be mentioned that such installations must be centrally situated, also that they must have excellent railway connections and be as near as possible to coal stores for the sake of cheapening working ex- penses as far as possible. At such centres the slaughtering must also be conducted under suitable supervision. To supply forts with Such freezing plants, is right on one hand, but in case of the investment of such a fort the supply of coal necessary for the working would only too rapidly vanish, the stores would spoil and constitute a danger for the garrison and the populace! If such centres for meat preservation were supported by a number of Smaller freezing plants in country districts, which might be used as halting places for troops, during, transport, the security of this manner of provision would be increased. The first question is how the frozen meat could be taken from such central depôts to the troops and arrive there in a state admitting of no objection. Every state possessess a railway net which is as extensive as possible. Direct from the Central depôt which must of course be on the railway, the prepared special waggons for meat transport, which must be loaded in a cool room, would have to be sent. The preparations of the cool waggons consist in fitting with cork isolation plates on all six sides, for avoiding loss of cold as far as possible. The spaces between the quarters, arising during the packing of the frozen meat, must be filled with a non- Smelling, good isolatung and easily washable material, for which peat mould would be very suitable. The quarters must be laid one upon the other Wrapped in thin linen sacks and before closing the waggon the pile of meat must be covered with thick straw matting. With such manner of packing the cold stored in the inner parts of the meat will last for days and it is entirely unnecessary that special waggons provided with small cooling machines, which are expensive objects, should be used. It must be at once admitted that if the transport of the meat trains to the seat of war be effected without hitch — and its safe and rapid arrival are as important ** * * 23 354 as those of the munition waggon — the spoiling of the contents is impossible. * - * * ...At the commencement of war large stores of frozen meat can be taken from such central depôt as near as possible to the district of operations and kept in slaughter house cold installations near at hand ready for use. The temperature in these rooms of 0 to + 40 C will permit of slow thawing, and at least a week will be required to reduce the meat to the temperature of the cool house, from which it would be taken for sending to the troops, so that even then three days can pass before de- composition will begin to become evident. Thus cool instalations, without their possessing freezing plant, have great value for the keeping fresh of the frozen meat placed in them. - - . " The matter should also be considered from the point of view that the cattle produced in any country cannot suffice to provision that land in time of war. This is of point to many states. --- & - To prevent great embarrassment great stores of frozen foreign meat must, in such cases, be collected into cold stores, the import being permitted free. Even in time of peace larger or smaller portions of troops must be provisioned with such meat; it is not necessary that they be accustomed to the flavour of such meat, but the technique of provisioning must be ex- perimentally proved. All troops in the land must in turn be provisioned from the central depôt, only then will sufficient experience be gained for case of exigency. The old stores must naturally be first used and con- tinuously replaced by fresh meat. Here the English model must again be considered. There the troops in camp at Aldershot are almost exclusively given frozen meat. This manner of meat provisioning presumes the existence of freezing stores near the coasts, and also of refrigeration ships. As regards the former, France has several in work and, she is also proceeding to make her own military abattoirs. - - Experience in storing and transporting frozen meat for the troops is of enormous hygienic importance, for, 1. it does away with driven herds which in every way further the spread of pest, 2. it enables such meat to be subjected to thorough examination at the place of production or at the store house, 3. it helps to the conveyance of very large quantities of meat ready for immediate consumption to the troops in the shortest trains, as but a quarter of the space is required as compared with that necessary for living animals and the transport of fodder for these is also unne- cessary, 4. a spread of pest is thereby entirely prevented and thus damage to the national wealth is actually prevented, 5. the provisioning of the army is thereby not only improved but also cheapened by the amount of the cost of transport for cattle and fodder, 6. the troops can be given ripe meat of the highest nutritive value instead of tough fresh meat. So far as concerns the transport of the frozen meat from the last station to the troops, the numerous motor waggons subsidied by the state 355 may be made use of, and may be sent in the same trains with each sending of meat. cy ‘...” If after short railway transport the meat is still in frozen condition it can be forwarded further covered only with light cloths, the quicker to thaw. If it is necessary that at the point of provisioning reserves of meat be kept in stock, the layers lying in the centre of the waggons, which naturally thaw most slowly, must be covered with isolating covers and forwarded and used for this. To-day one hurries by train in three days through Europe, why should it not be possible in quickest time to convey meat to troops from a distant depôt? If slaughtered flesh keeps fresh for three or four days the frozen meat will suffer no harm during transport, with proper care, and then will keep fresh for at least three days after thawing. If the forwarding is exactly regulated, this time will be sufficient always to have fresh meat ready. The use of frozen meat is of great importance in emergency for the carrying on of war to-day, it may also be practically effected without special difficulty if the good will does not fail. If in future conserves cannot be entirely dispensed with as nourishment, they will at all events play a far less important part than hitherto. The soldier in the field, on whose effective work all depends in these days, has a right to the best food, which, however, he cannot procure himself as the peaceful citizen can. He will have to be content with what he gets for his nourishment, and for this reason alone every state is bound to consider only the best good enough for the pro- visioning of the troops. . The following suggestions shall be put forward: 1. Meat food is indispensable for the nourishment of troops. 2. The present systems of provisioning must be abandoned for sanitary and national economical reasons. 3. The procedure of feeding troops with frozen meat must receive the greatest attention. 4. Every state is in duty bound to make the existing cold installations as useful as possible and to procure sufficient freezing plants for the case of war, from which troops shall be provisioned in peace times also. 5. The available means of transport and its speed will be sufficient to ensure that meat reach troops in fresh state from great distances. Modern states have proved to be progressive in all spheres, have made use of all technical improvements. It is their duty to entirely dispense with the old-fashioned, cumbrous, and certainly somewhat dangerous System of provisioning, so much the more so because thereby the mobility and readiness of an army will be increased, and their best powers be ensured to the state. 23% 356 The meat problem and the refrigerating industry. By Bezirkstierarzt und Redakteur Eugen Vámos, Budapest. No more actual theme could have been found than that of the question as to how the science of meat cooling ought to be applied in the whole- sale provisioning of mankind. The symptom nowadays felt in every country – even in pronouncedly agrarian states, if we wish to consider whether sufficient meat is available for the supplying of the masses of mankind — lends pressing actuality to this theme. - In the whole of Europe we hear but one cry ; *There is no meat, meat is dears. Yet a glance at the world's store of cattle, as given in the Agri- cultural Statistics of the Board of agriculture and fisheries, convinces us that only the latter part of this complaint is true and justifiable. Horses Cattle Sheep Pigs in Millions: Russia . . . . . . . . . . . 28-7 43'2 65'5 12:7 North American Union . . . . 18.7 66-9 50-6 52°1 Argentine Republic . . . . . 4'4 21-7 74°4. O-8 Germany . . . . . . . . . 43 19.3 7.9 18-9 France . . . . . . . . . . . 32 14'3” 17.8 7:6 Hungary . . * * * * 2-3 6-7 8'1 7-3 Great Britain . . . . . . . . 2:1 11-7 29.2 3:6 Austria . . . . . . . . . . . 1-7 9:5 2-6 4-7 Canada . . . . . . . • e . 1-7 6'3 1.8 2.2 Australia . . . . . . . . . . 1'6 8.3 72-8 1-0 Japan . . . . . . . . . . . 1'4 1.2 * * British East India * * * * 1-3 52-0 17:6 * Mexico . . . . . . . . . . 0-9 5:1 3'4 0.6 Roumania . . . 2 * * * * s O'9 2.6 57 1-7 Italy . . . . . . . . . . . . 0-7 5'O 6'9 1'8 Uruguay . . . . . . . . . . O'7 7-O 17.9 - Transport , 746 2808 3822 1150 357 Horses Cattle Sheep Pigs in Millions: Transport. 74.6 280.8 382.2 115'O Sweden . . . . . . . . . . . Jºe 2:6 1*1 O-7 Spain . . . . . . . . . . . – 2-2 13:3 1:9 Bulgaria . . . . . . . . . – 18. 6'8 O-5 Denmark . . . . . . . . . . — 1’8 O'9 1-5 New Zealand . . . . . . . . — 1.8 20:1 *º-º-º-º-º: Belgium . . . . . . . . . . — 1-8 O'2 1-0 Holland . . . . . . . . . . — 1-7 O'7 O'9 Switzerland . . . . . . . • – 1.5 O'2 O'3 Cape Colony . . . . . . . . — 1:9 11.8 wº-mºmen Algeria . . . . . . . . . . . — 1°1 9-1 . * Servia . . . . . . . . . . . — 1-0 3:1 1-0 Norway . . . . . • * . e. e. T 1'O 1“O *-*. Natal . . . . . . . . . . . . – O'6 O'6 &ºmºs Other Countries . . . . . . . 3.5 *E=º * = O'8 78.1 301.6 447.1 123.9 Mankind thus disposes of 301 millions of cattle, 447 million sheep, 123 million pigs and 78 millions of horses (to-day these already count among the most important foods). If the average weight of the above ani- mals be considered, the available store of cattle gives a quantity equal to about 78,750 million kilos. Of meat at the disposal of 1500 million people. As man requires 100–120 grammes of albumen daily, and meat, according to Voit, contains 20% of this substance, this 78 odd million kilos, would suffice for four months even if mankind lived solely on meat. It is generally known that mankind derives the greater part of the necessary albumen from vegetable foods, so that the meat available is suf- ficient over and over again for the replacement of the lost albumen. Meat is thus available in sufficient quantities. If in spite of this we experience a scarcity of meat, then this is due, apart from local conditions of slighter importance, to two great main causes: One of these is that mankind be- comes continuously more industrial. I must here presuppose it to be an erroneous idea that the industrial population of a large town eat more meat because they are more prosperous, or because the requirements of the in- habitants of a town are far higher than those of their provincial cousins. The industrial citizen is incessantly influenced by an inner instinct towards meat nourishment. According to Conheim, the whole nourishment requirement of man- kind depends, almost solely upon the muscle production. Mental work hardly comes into consideration. Whether anyone exerts his brain or rests it has no influence on the energy requirements of the body, because the quantity of energy necessary for the maintenance of the temperature of the 358 human body is quite independent of it. So much the greater is the in- fluence of muscular exertion. In a warm room a man not having either physical or mental, work requires daily from 1500–1700 calories with a sitting occupation he uses up 2100–2400 calories; during light muscular work his requirements are 2800 calories; and the needs of agricultural labourers rise to between 4000 and 6000 calories. Thus the man who does hard physical labour has need on an average of double the number of calories (4500) needed by a man who rests. This gives the following result: Since the caloric requirements vary according to the kind of labour while the requirement of albumen is quite stable and independent of the work, those men who do less physical labour and consequently eat less require a nourishment that, is richer in albumen than do those who perform hard labours, because the smaller amount of food required by the former contains correspondingly less al- bumen. Meat has the largest albumen content of all foods. It is therefore natural that the inhabitants of towns who do less physical work, require comparatively more meat, while country people obtain the necessary albumen from larger quantities of vegetable nourishment. The history of nourishment and the history of the development of individual races prove that the requi- rements of meat increase in proportion to the decrease of muscular labour. The matter becomes still more clear if we now compare the food of town dwellers with that of country people. A countryman who performs hard physical labour requires nourishment that produces at least 5000 calo- ries. He lives chiefly on vegetable food (bread and potatoes) and the quantity of this from which be gains the 5000 calories, contains at most 100 grammes of albumen. When he goes to live in a large town he no longer needs 5000 calories, but is statisfied with half this amount. If then he keeps to his former diet he must reduce his daily quantity of food to the half; ; he cannot eat more. This reduced quantity only contains 50 grammes of albumen and he must therefore make up for the deficiency in this respect by eating meat. According to the above, therefore, the countryman, in correspondence with his manner of living, his work and nature, can subsist on vegetable nourishment, whilst the town dweller must eat meat if he wishes to live conformably to his work and nature. The process that we may call flight from the land is nothing else than the streaming of the villagers into the large towns, connected with the continual increase in the consumption of meat, which makes itself felt in the whole world. For example one fifth of the total population of Germany lives in 41 large towns, and the migration from the country districts into the towns still continues. In Hungary, too, the population of the capital has enormously increased during the last 20 years, although a very large country population has been compelled to emigrate on account of want of employment. One solution of the meat problem there- 359 fore, lies in the motto "back to the lands; for the present, however, this in utopian, for these questions cannot be solved by mere sayings. We perceive from above, therefore, that the store of meat in the world is a sufficient one. But we can also see at a glance that the store of meat of individual countries stands in no proportion to their requirements. The industrially important states of Europe, which ſorm the chief meat con- Sumers, possess, together, scarcely the fifth part of the worlds meat supply, whilst Russia, the Argentine Republic, Canada, Australia and British India, and even America dispose of such quantities of meat as show a great Sur- plus over their requirements. From this we simply get the result that, without consideration of the distances separating various states, the world's Store of meat must also be influenced by the meat problem in a manner similar to that in which corn is influenced. Doubtless the world's traffic in this most necessary article of consumption must not be limited in any manner, nor may it be permitted that in the twentieth century the import of meat and bread be hindered. We know well enough that formerly meat could only be conveyed alive from one Country to another, so that the world's meat traffic could not properly cater for the welfare of mankind to the degree necessary, on account of the dif- ficulties of transport, great expenses and risks, and sanitary matters. The various governments were quite ready to find excuse, particularly in sanitary matters, for protecting interested parties of individual states against the import of cattle. All difficulties, such as distance, risk, and sanitary dangers, for instance have now been overcome through the development of the technics, or rather the science of meat cooling. The solution of the meat problem, therefore, lies in the science of meat cooling and consumption. That frozen meat Stands the longest transport is no longer doubted. England's import of frozen meat, through which the English have become the, greatest meat eaters is the best proof that such import is of special advantage. As already stated frozen meat not only stands the longest transport but also requires no special railway arrangements, though even if it did, such would be already necessary for social reasons. If there were sufficient cold waggons on all European railways, the continental meat transport would be exceedingly easy, yet we know quite well that ordinary waggons would also be suitable if the side walls and the ceilings were suitably insulated. Even such transports would sufficiently protect the meat against the moisture in the air, and, on the other hand, the frozen meat so cools the temperature in the waggon that it will stand many days’ transport in fairly dry air. Present day express traffic, for in- stance, would enable meat landed at Pola - or Fiume to pass the whole continent in the course of a few days. Such transport, too, is much cheaper and free of risk, that is, this risk is in no proportion to that incurred in transporting living animals, since over-sea transport of living animals is im- 360 possible. It is, indeed, argued that frozen meat suffers in quality, but this is - only said because frozen meat is much cheaper at the point of import than home-grown. Naturally the argument fails when it is remembered that at the place of export the meat is so extremely cheap that in spite of enormous trans- port expenses it is cheaper and more fit for competition at the point of import than is the home-grown. One might say with just as much reason, for instance, that Argentine corn was of lower quality than the European article because it is cheaper in spite of the expenses of import. In a word, frozen import meat is not cheaper because it is not eatable, but it is for Europe a useful food on account of its cheapness. The second argument against it is that frozen meat must be consumed immediately after arrival because it otherwise spoils. This would also happen however if the meat were to remain loose or at the butchers in an ice-safe. In the case of a large meat import, however, this evil can be easily over- come, it being only necessary that municipal slaughter houses be provided with cold stores. The butcher could then leave the frozen meat there for weeks, and always simply fetch away his requirements for the day. If this be undertaken to-day by private societies, it is, nevertheless, the primary duty of separate communities to erec, such cold stores. That the counter arguments are unfounded and that frozen meat is very suitable for food, are best proved by the fact that the army has, after thorough trials, found the import of frozen meat to be a success. I will merely give a few data here. The German army uses chilled and frozen meat in times of peace, and in times of war, too, it disposes of sufficient frozen meat to last 200 days. The English army is also fed on frozen meat during a great part of the year and would be fed solely on it in times of war. At Aldershot the soldiers receive frozen meat three times weekly, and they consider it excellent. The armies of the United States, the Argentine Republic, and of Australia are also fed exclusively with frozen meat in times of war. In the South African war the English soldiers also received frozen meat. If then frozen meat is usable by people who have good appetites, where sanitary matters are most sharply studied (i. e. in war), how much more suitable is this meat for the nourishment of fastidious citizens. One argument then, finally, in favour of frozen meat. Those Sanitary objections which hinder the transport of living animals, would for the most part become negligible in an international traffic in frozen meat. The leading states are working together to base the control of meat upon uniform fun- damental principles, and this will then form the guarantee for international traffic in frozen meat. Following Germany's initiative the leading states are, one after another, regulating the control of meat by laws and prescriptions, and this On a uniform basis, which fact is to be ascribed to the Inter- national Congress of Veterinaries. - 361 If this movement progresses in this manner it will be possible within the shortest time that the control of meat may be managed, both on the continent and in over-sea countries, by equally qualified experts, under state supervision, and this would lend us the comforting feeling that the meat was subjected to the same control at the place of export as at the place of import; as a matter of fact it is also to the interests of the exporting states that they exercise the same control as the importing states do. For the rest it is also generally known that frozen meat is transported in pieces of such size as can be easily controlled. If then the above men- tioned be carried out, conditions will be introduced far superior to those which exist at the present day. Apart from the fact that the cold chambers installed in slaughter houses reduce the loss of weight in the meat to a minimum, there is also a special advantage therein, namely, that the prices would be quite independent of the living animals. Herr Dr. Julius Braun, director of the cold stores of the Hungarian Food Transport Company, was so kind as to place the following data at my disposal. Between 10th December 1907 and 28th January 1908, that is within a period of about ten weeks, 23.705 kilos. of meat were stored. The weight on removal, however, was only 22.986 kilos., so that the loss in weight during ten weeks was only 3°io. There was also a large quantity of flat cutlets stored from the end of May till the middle of September, i. e. about 41/2 months; further about 40 q. of breast were stored from Febru- ary till May in a frozen state, without either the meat suffering in quality or becoming in the least tainted. The owners of this meat weighed it out without the least hindrance or loss. For times, therefore, when the price of living animals rises, we can reserve such a store of meat that we do not feel the abnormal rise in price at all, for hereby we are in a position, when the price of living animals is high, to place on the market meat that was bought when the cattle was cheap. - By this means not only would the cost of storage be well covered but we also avoid the danger that the abnormal rise in prices threaten both butchers and consumers with ruin. The task of the authorities, therefore, would be to erect public chill- ing and freezing chambers, or to support the erection thereof, with a view to regulating prices. The very least, however, that we can expect of muni- cipal authorities, would be that they provide the slaughter houses with modern cold plants, for the loss that the butcher has to bear through the want of cold plants is in reality only felt by the consumer. - The butchers in towns pay very high rates for slaughtering, and, therefore, may with justice expect the authorities to meet them half way. The Hungarian Cold trades society has requested the government to make it a duty for every town to erect cold plants in the slaughter houses, for the protection of the general provisioning and sanitary interests. It is 362 then very desirable that the societies of other lands also act in a similar Iſlan1101. -xx - By systematically making use of the achievements of the modern cold industry the solution of the meat problem would be made possible, and therefore I recommend the. following propositions to the attention of the II International Congress of Refrigeration. - *-- 1. The Congress demand that the international traffic in frozen meat be regulated by state contracts, further that railways provide the necessary arrangements for the transport of frozen meat, and that the slaughter houses of large towns be provided with cold plants and freezing rooms to make it possible to store imported meat. -- 2. The Congress demand uniform meat control, in the leading states, in order to make traffic in frozen meat more easy. ‘. 3. It is desirable that in large towns municipal or private cold and freezing stores receive state support, and that the erection of cold stores at slaughter houses be made compulsory. * 363 Changes in the Physical and Morphological Conditions of Food Stuffs (Meat, Fish and Milk) by Cold. By Dr. Bützler, Director of the municipal Slaughter House, Cologne, A. Changes of the flesh through Cold. There are two ways of preserving meat by means of low temperatures: 1. By freezing it, - 2. By storing it at a low temperature above 0° C. We have therefore to consider: 1. The changes in frozen meat, and 2. the changes in cooled meat. I. Experiments have been made at the military fiscal freezing plant at Thorn, on the changes that meat undergoes when subjected to cold. For the experiments 2 Oxen, 3 Pigs and 3 Sheep were used. The object was to decide: 1. The time necessary for slaughtered flesh, hung in a freezing room, to freeze right through; 2. how long frozen meat keeps, and 3. what changes take place in the meat during the storage. The oxen were quartered, the pigs were halved and with the sheep which were not divided, were placed in the refrigerating plant on 27*November. On the second day the temperature had already sunk below 0°C. in every case and rose by August of the following year to 4°C. The freezing took place most quickly with mutton and most slowly with beef. The following changes in the flesh were noted: In February the beef received a blackish, the pork a gray surface. 1 to 15 millimetres below this, however, the meat was juicy and of livid red colour. Further a gray white layer was observed on the surface of the whole of the meat. In March the beef became mouldy, but this could be rubbed off the meat, and improved ventilation put an end to it. In weight the meat had, through loss of water, decreased 88 per cent. (beef), 7.4 per cent. (pork) and 11.5 per cent. 364 mutton), after nine months, however, 17.8 per cent. (beef), 12.8 per cent (pork) and 23.4 per cent. (mutton). e The gray-white covering consisted partly of separated meat salts, partly a superficial settling on the meat of coccus and yeast which formed a powdery or frost like covering. The change took place with relatively dry meat surfaces, if the lessening dampness prevented the development of the decomposition germs, which otherwise would overun the coccus and yeast. The germs multiply best at ordinary room temperature, but just as much also, though maybe not so rapidly, at lower temperatures, especially in the cold house; they do not go deep, but form a surface process. On thawing not only does steam settle on the meat but much juice also flows off; to explain this it is necessary to describe shortly the histological construction of the muscle flesh. With the naked eye it may be recognised that the muscles consist of reddish, coarse, parallel fibres, which, with the aid of the preparing needle and a 75 per cent. Solution of common salt, may easily be dissected in longitudinal direction into very fine, unbranched fibres, which are known as muscle fibres (Muscle primitive groups). Each of these muscle fibres represents at the same time a tube, formed of a delicate, water like, structureless membrane, and known as muscle tubing (Sarcolemma or Myolemma). In this there is a soft, brothy content, the muscle juice (contractile muscle substance). The individual muscle fibres are connected into thread like bundles by sparsome quantities of fine binding tissues, so-called 1oose binding tissue, the second main part of muscle, and these thread-like bundles are joined by larger quantites of binding tissues (intra muscular binding tissues) to form the separate muscles. ' The flowing off of the meat juice is accounted for by the fact that the muscle fibres through the freezing of their contents, the muscle juice, tear and burst. f The fresh meat differs further from that preserved by freezing in the condition of the small red blood-vessels, which in the former appear yellowish under the microscope and are of normal condition. In frozen meat all blood vessels are deformed and completely colourless whilst the normally colourless fluid is now dark coloured. According to Malchan frozen flesh does not contain a single red blood vessel; they are all decayed and have a green colour in consequence of the decay of the red blood colouring matter. For the rest no disadvantageous change or decrease of nutritive content takes place in frozen meat. This was also proved by the Thorn experiments. When the meat was taken from the freezing room, in the following August, and distributed to the troops, it was noted that it not only cooked well but that it also had a very good flavour and was not distinguishable from fresh meat. It needed but half the time to be well-done, made good soup, and was especially tender and juicy in roasted state. A piece of meat when thawed, however, must be consumed within 24 hours at longest, for after this time it loses colour and shows signs of decomposition. 365 In the freezing rooms of the Hamburg cold plant storing trials have had equally good results. Trials were made as early as 1899 by the French goverment at manoeuvres. Ihe flesh frozen at — 17° in May, by refrigerating machines, was immediately after freezing packed in hermetically closed boxes. In distributing to troops it had to be carefully observed that the boxes were not opened until just before the meat was to be used, when it was to be cooked at once because it began to decompose even if but for a short time exposed to the air. Although the meat had by no means a fresh appearance ontside, it was yet matritious and juicy and was preferred by the Soldiers to conserves. At such world centres as London, and everywhere where there is the object of getting large quantities of meat as reserves, the freezing system will be the best for the purpose. By the enormous import of frozen meat into England the conditions ruling there are best catered for; every consumer can obtain the best quality he is able to purchase, as there is no want of choice. That the quality does not suffer in consequence of the long freezing is proved by the perfect appearance and the excellent condition of the frozen meat. II. Changes in the coole d meat. The freezing of the flesh is not everywhere suitable for the carrying on of business; for inland meat we give preference to cooling, that is a temperature of some degrees above freezing, for maintaining the meat in its fresh state for longer periods. Of the changes the first place is occupied by the loss of weight of the meat in air-cooling. Not only the air of the cold house, but also the object to be cooled, the flesh, loses moisture, so that its upper surface dries and in consequence of the loss of water it loses in weight. This loss in weight, which is fairly large even while the meat is hanging in the fresh air, is often ascertained by trials. Trials in Cologne with the flesh of measled oxen, which was stored in the cold room for 21 days, showed a loss of from 4 to 4!/2 per cent in this time; it is conditional here that the animal bodies are cooled in halves, not in quarters. Trials were made in the cold house at Leipzig with a leg of beef, one of veal, of mutton and of pork. After seven days the weight of the leg of beef had decreased 1.8 kilogram, the leg of pork and the leg of veal 0.5 kilos each, and the leg of mutton 0.3 kilos. No further loss took place up to the end of the trials (with the veal and pork after two weeks, and with the beef and mutton after four weeks). The following particulars may be given of the experiments made at Halle, During 8 days storing at 4° C. */, bull weight 71 kilos lost 3"/, kilos */, pig K 44/, « • 1"/s K 1 calf K 38 & < 3"/, & 1 sheep & 351ſ, K < 1°/s & 366 on the other hand a quarter of beef which hung for days in the hall of the slaughter house in warm dry air (25 to 30° C by day in the shade) weighing 87 kilogrammes lost 6 kilos. Each of the above pieces of meat were placed on the scales for the first weighing in dry condition and cooled to the temperature of the outside air. It is thus apparent that the meat loses more in weight in warm, dry summer air than it does when kept in the cold-house. The losses in weight of small pieces of cut meat are quite different to the losses on whole quarters. Thus the trials which took place in the cold-house at Stolp gave the following results. A piece of beef weighing 3350 grammes lost, 850 grammes in 22 days, 350 grammes more in further 17 days, 230 grammes more in the next 28 days, total loss 1430 grammes in 67 days = 43 per cent. The meat was very juicy and had a fresh, agreeable smell. The dry layer was after 14 days three millimetres thick, black-red to black, like smoked meat. Horse flesh after 45 days had a dry layer of 15 millimetres. Another piece of beef of 5850 grammes lost, 1485 grammes in 15 days, 335 grammes during the following 25 days, i. e. 1820 grammes in 40 days =31 per cent. All these great losses are to be accounted for by the fact that cut meat, that is meat deprived of the under skin covering, is much more liable to vaporation than covered flesh. Low temperatures penetrate into the flesh rather slowly. Experiments at Cologne showed that it took two days for the temperature of the cold house (2° C) to reach the inner parts of the neck muscles of a quarter of beef. Zschokke took measurements with a long thermometer, which was sunk deep into the upper crural muscle of a slaughtered ox. This back quarter was kept in a small room the temperature of which was fairly constant. The temperature of the room was 6° C at the beginning of the measurements, fell by the evening to 5" C, was 4°C early on 9" January, rose towards noon to 5° C fell again to 35° C and early on 10* January stood at 3" C. The ox was killed on 8th January at 10 a. m., the following tem- peratures of the muscle were noted: At 1 p. m. 30° C 33 3 93 3) 260 C 3) 5 35 55 220 C 3} 7 33 33 210 C 9th J an u a ry: At 530 a. m. 12" C 99 830 99 }} 110 C 9) 1 93 }} 80 C 9) 5 5) }} 60 C 10th I an u a ry: At 830 a. m. 30 C 367. Thus to cool an ox from 30°C to 3° C requires 40 hours. In connection with the changes in the flesh in cold houses those due to the effect of ice bacteria must be mentioned. In the cold house exten- sive vegetation of bacteria takes place superficially, with no special incli- nation to peretrate deeper. Among such are many germs of koli or proteus nature Gelatine little or not at all fluid and often in cultures smelling like fruit (Aroma bacteria). The stormy white of egg decomposition, specially marked by putrefaction, decreases very much owing to the effect of the cold temperature. The surface of the meat is sometimes covered with bead colonies, which are generally of coffee or yellowish colour. The smell is also not upleasant but strongly ethereal. Green shades occur but seldom, in spite of the enormous quantity of bacteria. The effect of the cold in the preservation, thus consists less in absolutely suppressing bacterial vegetation, than that the energetic white of egg decomposer cannot flourish under it. Only a freezing temperature will entirely stop the putrefaction. If cooled flesh is placed in the open air, it decomposes quickly, as not only is the surface impregnated with bacteria, and with rapid change of temperature moisture is deposited on it, but the thanatological decomposition of the muscles also assists the bacteria to penetrate deep into the flesh. B. Changes in fish caused by cold. All fresh sea-fish, bought inland, must be considered as conserved, for they arrive dead in the kitchen, and are only brought from the harbour to the town with ice packing. Even with this method care is necessary, as the melting ice water may lixiviate the fish. In the same way a hard freezing decreases the fat in the inner parts, it comes out and makes the fish hard and tasteless. Freezing unfavourably influences the muscle flesh of fish. The muscles consist of segments lying one behind another, the myomers, since the anatomy of the fish is bilaterally symmetrical. Consequently the separate muscles are situated in lumps and bound together by binding tissues; as the binding tissues contain large proportions of water, freezing loosens the segments and forces them apart causing the fish to break up into lumps. To this is to be attributed the rapid decomposition of frozen fish. The preservation of fish through cold is best effected with temperatures close to zero, but not below it. In every fish wholesale shop in Geestemünde the fish in preserved on ice, of course, without allowing the fish to freeze. In transport, too, the fish are laid between chopped ice, to which in summer salt is added. They are sent in parchment paper and packed in willow baskets with straw filling. The weight of ice used is equal to half the weight of the fish. It is considered important that the ice water keep the lower part of the fish moist; lixiviation must, of course, not take place. 368 C. Changes produced in milk by cold. P. Vieh t allowed 10 litres of milk to freeze. The ice block formed, which consisted of fine crystals, had a funnel shaped hollow in the centre which was filled with the still liquid parts of the milk. The uppet part of the block consisted of a sharply defined layer of cream. Two trials gave the following composition of the layers: Ice Cream Ice skimmed liquid part milk Specific gravity . . 10100 1-0275 1'0525 Dry substance . . . 2556 7-90 1946 Protein . . . . . 264 2.80 5:38 Fat . . . . . . . 1923 O'68 5:17 Milk sugar . . . . .333 3.95 7.77 Ash . . . . . . . '52 ‘60 1°18 Quantity . . . . . 8:8 64-7 26'5 If we consider Protein, milk sugar and ash we find that they stand in -- the following proportions to each other. Ice cream ice Skimmed liquid part milk Protein . . . . . 40.68 38° 10 37:55 Milk sugar . . . . 37:31 53-74. 54°23 Ash . . . . . . 8:01 8’ 16 8:22 Those three milk constituents, existing partly dissolved in water and partly very closely mixed with it, took part in the formation of the ice to an equal degree. In judging whether milk that has been frozen, is pure or not, it must be remembered that the milk-ice, separated from the part that remained liquid, when again thawed is by no means the same as the original milk. The freezing of milk, therefore, differs from the freezing of water. The frozen part is characterised by the loosely lying little ice-tablets, by which the part still remaining liquid is mechanically enclosed. By pressing the ice mass and draining on a strainer it is easy to separate the ice from the liquid part. The ice thus obtained was melted at room-tempe. rature, and each separately analysed. (Professor Dr. Kaiser and Dr. Schmieder Hannover.) I. In order to be able to compare the results obtained wilt the normal constituency of ordinary milk, the latter was also determined at the same time. It was then found that the particular milkman, in order to deliver especially good milk, had added a certain quantity of cream. Further the milk showed on receipt no double reaction but a strong sour reaction. The results were probably but little influenced by this, as it was only required to prove that the proportion of the constituent parts of the liquid part were different to those of the ice. Whereas Vieht, in proportion to the 369. whole mass only collected a very small quantity (12%) of ice, and compared it with the strained off part, Kaiser and Schmiede, in the cold days of January, allowed the milk to half freeze, so that the quantity of liquid. separated from the ice about equalled the melted ice. By the addition of the cream the proportion of fat was increased, but apart from this difference it may be accepted as normal. In table 1 the results are given; for the sake of comparison the table contains a rubric from which the average composition of normal milk is deducible. Table 1. sm-mm- * | Average 3 Co m p on ent & a tº Milk Liquid composition Ice p a r t S normal milk used part } Sl —sº- - * | 42 | Reaction . . . . . . double sour very slightly a ; \, SOUIT sour | # 2 #| Q1) Sº E Degree of Sourness . * 2 3 1 5 : ..] Specific gravity . . . | 1.025–38 || 1:029 || 1040 | 1015 || 5 || || | Casein . . . . . . |35 – 50 318 || 4:42 257 || 3 : Fat. . . . . . . . || 3:0 — 4.5 | 7:40 4°11 || 10:10 É º; E | Milk sugar . . . . || 3:0 — 5:0 3.90 5-95 214 || 3 = 8| Salt . . . . . . . . 05 – 075 059 97 50 || 5 g | Dry Substance . . . 12:5 157 1545 | 1531 |# 3 # | Water . . . . . . 86–89 84-93 | 84.55 | 84-69 | * From the composition it follows that the constituents which are con- tained in solution in the milk, such as acid, casein, milk-Sugar and Salt collect principally in the separated liquid and consequently cause a higher specific gravity in the latter, whilst the fat is chiefly contained in the ice, lessening the specific gravity of this part. The quantity of dry substance is the same in all cases, but it consists of totally different factors in each part as is evident from the table. - II. As the above milk did not satisfy the requirements, a second Sort was subjected to the same operation, half frozen. On another occasion the same milk was entirely frozen in one night, and afterwards by gradual thawing in the room the half of the liquid obtained, the remaining ice was separately melted. The result was different in each case, as is seen from table II. For comparison the composition of the milk used is also given. The dry substance contained is in both cases considerably greater in the liquid part, which would also be the case in I, if this minus had not been equalised by the high proportion of fat. According to this the wate 24 370 content of the ice must be higher than that of the liquid fart. Acids, casein, milk sugar, and salt are contained in the liquid part in far the greatest proportion (as in I), wherefore the latter has a higher specific gravity than the melted ice. As regards the fat this time a different con- dition appears to the above which was equalised by the addition of cream. In the first case the proportion of fat in the ice is greater than that in the — Average - Component parts Compositiou Milk used PHalf frozen Eintirely frozen || of normal 4. milk Liquid | Ice || Liquid | Ice Reaction . double SOUlſ very slight | very | slight | sour ly sour| sour ly sour i Degree sourness . — 1.5 2.5 1-0 || 30 || 05 i | Specific Gravity. || 1:025–38 1.032 || 1:048| 1016|| 1:061| 1:006) Casein . . . . 3.5 — 5:0 3:44 4:72 | 1.92 || 5-27 | 1:24 H Fat . . . . . . 35 – 45 || 2:40 || 1:68 || 3:06 || 263 || 2:02 | Milk sugar . 3.5 — 5:0 4-26 6:15 || 2:52 || 9-32 O'85 Dry substance 12:50 10'76 13.60 || 7-93 |18:52 4:28 Water . . . . . 86–89 89 24 86°40 |92:07 ||81'48 |95'72 i liquid part; in the second case it is less. The reason lies in the different rapidity with which the in the milk freezes. If it freezes quickly it has no time to form cream, consequently, as the butter fat is suspended, it exists in equal quantities in the liquid and frozen parts, being mechanically enclosed in the latter between the little flat crystals of ice. If the milk is now thawed the original proportion of butter fat ought to be found in the liquid part. This is, however, generally somewhat greater, because the liquid flowing off from between the ice crystals always carries a certain quantity of fat along with it. It is different, however, if the milk is slowly frozen. The fat rises and is enclosed by the ice-crystals. The liquid part flows off between the crystals, while the ſat is mostly mechanically detained. Thus is the quantity of fat, as also, on the other hand the poverty of both parts in fat explained. The liquid part, richer in dry substance, forms cream but slowly, whilst, the melted ice mass very quickly separates the butter fat. While the latter, however, in consequence of the high percentage of water has a bluish appe- arance, and on standing separates off a considerable quantity of water, the liquid part forms a completely homogeneous mixture after souring has set in. Thus one may well say that the liquid part generally contains the larger quantity of fat, though not in all cases. From all this it is apparent that one should never sell milk that still contains ice, but should always 371 make sure first that the ice is melted. Only then, after the milk has again Theen shaken is the milk of the original constituency and again saleable. If the milk has to undergo long tranport the process invented by Ingenieur Casse in Copenhagen must be employed. He allows a part of the milk to freeze, and places this block of ice-milk in four times its bulk of milk; by this the temperature of the milk is kept constant at 0°, so that changes £annot take place in it. Ice-milk is said to keep fresh for six weeks. On selling the milkice must be completely melted, as the frozen parts are richer in water and poorer in solids. **. 24% 372 Changes, which may be induced by cold in the physical, chemical, and morphological composition of foodstuffs, especially meat, fish, milk and its products, fruit etc. - . By Dr. L. C. Query of Paris 2 bis rue du Bouloi. This question, besides being of considerable importance, presents such complicity that I will be obliged to treat it within certain limits which it. will be as well to determine in advance, intending to develop and ultimately complete it as much as possible. There is room to take account of the effects of varying the degree of cold, as well as those of the different arran- gements used. Also the experiments which I have the honour to submit to you will not be able to solve all the problems of application, although, with- out doubt they will solve some of them. Progress can not be made with- out meeting with rebuffs and failures which are inevitable. Before proceeding with these experiments, I have held to the course which I have taken of not consulting any previous experiments made on the same subject, without satisfying myself as to their value, desiring to work as far as possible by my own methods, and desiring above all not to allow myself to be influenced by results which may agree or differ and might have been obtained in the same way. My investigations have been carried out upon meat, fish, butter, milk and grapes. ...” - The meat was a piece of chop, that is to say stringy meat, stripped as much as possible of fat, and coming from an animal killed the day before. The fish was some colin, bought at Halles and used on the day of arrival. The butter was some coming from Isiguy bought from Nostier & Co. and churned the day before. The milk, treated on the same day as provided, came from the same cow and was bought from a Paris establishment, whose cows had been in pas- turage for a whole 3 months. - The grapes, black and white, were taken as fresh as possible in appear- ance, but we should take note of the fact that they were taken in January. I proceeded to make a preliminary chemical, macroscopic and micro- scopic examination of the above different substances in a fresh state, then 373 I submitted them for twenty one days to the action of a temperature bet- ween 0° C and 4° C. A second examination was made on the tenth day, and a third on the twenty first day. Besides this I froze part of the various substances by means of liquid air at –1809 C, and I also made an examination of these after having exposed them to the same temperature of from 0° C to 4°C. The following are the results which I have been called upon to state Fresh Beef. Viewed by the naked eye, the meat appears of a fine red colour slightly tinged with blood, and of that reddish brown colour where it is cut, which colour is always observed on meat of good quality. Microscopially viewed, it had the scaly stringy appearance of tissues touching each other. No traces of bacteria were found either in the interior or on the exterior of the meat or in the blood wich issued from it. In the chemical analysis I worked by taking a sample of 100 grammes Water . . . . . . . . . . . . . . . . . . . 67.70 grammes Solid Matter . . . . . . . . . . . . . . . . 32:30 X Fat , . . . . . . 2:20 X Matter extracted from 100 grammes by dessica- tion upon a stove at 100° C until constant weight was attained . . . . . . . . . . . 11.90 X C1 present in H. Cl . . . . . . . . . . . . 0-1630 x Phosphorous > > P2O5 . . . . . . . . . 0-2488 × Sulphur » 2 SOs . . . . . . . . 0-1034 » Potassium × » K2O . . . . . . . . . 0-5259 X. Sodium X » NasO . . . . . . . . . 0-1915 X Azote total . . . . . . . . . . . . . . . 14042 > In vacuum and in sterilised tubes, meat frozen by immersion in liquid air at –180° C regains its original colour, consistency and appearance after about half an hour. - In a tube simply sterilised, within which no vacuum has been made, the same meat, frozen at –180° C by liquid air regains its normal character, consistency and appearance at the end of about an hour and a quarter. Meat frozen in this way by liquid air at ~-180° C in two sterilised tubes, in one of which a vacuum had been made, was subsequently sub- mitted to a temperature of from 0° to +49 C for 3 weeks. At the and of 10 days the first sample of 100 grammes was examined. Odour : Nil. - Exterior appearance: Red colour a little darker than on fresh meat, and to a depth of about 5 mm. . Appearance in the centre: Normal. 374 -- Upon microscopic examination, on the exterior, bacteria in conside- rable numbers, in the form of lines of about 8 or 10, and some cocci, the - muscles were disintegrated a little, the scaly appearance could "only be observed in places and the cellular centres were intact. In the centre, occa- sional bacteria, mostly in the form of cocci grouped in twos; some still less frequent formed in lines. The examination of the liquid which issued from these samples revealed a quite pure culture of the above bacteria. From a chemical point of view the 100 grammes of meat only weighed 94 grammes, a less weight of 6%. Extract from 100 grammes of meat after dessication on a stove at 100° C until weight became constant 11.376 grammes * Chlorine as H. Cl. . . . . . 0.04220 grammes in place of 0.1630 grammes Phosphorous in P.O; . . . 04361 X > x > 0.2488 X Sulphur in S. Os . . . . . 0-0740 X > x > 01034 X Potasium in K2O . . . . . 03703 * » x > 0-5259 X). Sodium in Na,C) . . . . . 0-1461 X > * > 0, 1915 }. Azote total . . . . . . . . 12722 X) > * > 1'4042 } There is, then, a diminution in the total weight of the extract in the chlorine present as H. Cl, the sulphur present as sulphuric anhydride, and less pronounced in the sodium and the Azote; there is on the contrary an increase in phosphorous present as phosphoric anhydride. tº Although we really worked upon 94 grammes of the substance, the calculations are given as based upon 100 grammes. Examination of 100 grammes of meat which has remained for three weeks at 0° to + 40 C. Exterior examination by the naked eye ; whity grey mould on the surface, fresh smell, blackish appearance. - * In the interior: the same fresh smell, deep red colour, but of normal appearance. No disintegration of the tissues. Microscopic Examination: on the outside the same, bacteria as in the former case, lines and cocci; here the exterior bacteria had reached the centre, where could be seen many more lines and (cocci). Few traces of scaly tissue. - Here again, of the 100 grammes, only 88 remained, a loss of 12'ſ, Nevertheless, account must be taken of the amount of liquid which has escaped into the receptacle, however small it may be. - The chemical analysis has not been made, it being thought that this meat, preserved 3 weeks under above conditions could not be considered as edible. Nevertheless it was interesting to find out the septic power of the bacteria which had thus developed upon it. To accomplish this, after having made a section of the meat through the centre, by means of a bastouri passed through a flame, I cut off some 375 pulp which served me to start bacteria in two flasks containing soup made of sterilised beef, and I placed these two flasks on the stove at 37° C. The soup grew uniformly turbid during the following 12 hours. Towards the fourth day the odour became extremely strong, then this odour lessened until it entirely disappeared. This odour resembled that given forth by the meat which provided the cultures. At the same time the bacteria in the form of lines almost completely disappeared and only the cocci in the form of diploes, noulae, and also tetragines were visible under the microscope. The Soup was clear on the surface and contained a turbid precipitate. Two rabbits of medium size had injected into them in one case 5 c. c. of the Soup taken before agitation of the liquid, in the other case 5 c. c. of the Soup made uniformly turbid by agitation did not suffer any trouble, and reabsorbed the liquid within 24 hours. These bacteria have no septic effect upon rabbits. The injection was subcutaneous. The piece of meat frozen by liquid air at –180° C and subsequently left for 3 weeks at 0° to 4° C had on its surface a blackish appearance while in the vacuum. In the centre its appearance was normal but a little more pale. No odour. On microscopic examination, lines of bacteria and cocci in profusion. - The piece which was also frozen by liquid air and preserved without a preliminary vacuum for 3 weeks at 0° to 4" C had kept its red colour on the surface, but gave forth a musty smell, and was taken out in a yellowish condition of putrefaction. Along side of these experiments, I placed some meat for 3 weeks at a temperature of from 0° to 4" C in a glass of free air, itself surrounded by ice. After the lapse of this time the surface was covered with mould, but the interior had a normal appearance and it did not give forth any odour. Fish. The fish under examination was in a perfectly fresh condition, and >ven though the results given below may differ according to the variety of fish, they give us interesting information, because we find here the facts already stated for meat placed in identical conditions. & Appearance to the naked eye white flesh, slightly moist next the bones and at their bases, slight odour of cod-liver-oil. Under microscopic examination; no trace of bacteria. Chemical examination Percentage Extract obtained by dessicating on the stove at 100° C until weight was constant . . . 12,791 grammes. Water . . . . . . . . . . . . . . . . . 74.500 > Solid Matter . . . . . . . . . . . . . . . 25.500 X Oily Matter . . . . . . . . . . . . . . . 2,000 X Chlorine as H. Cl. . . . . . . . . . . . . 0.3536 X. 376 Chemical examination Percentage Phosphorous as P, 0, . . . . . . . . . . . 0.6345 grammes. Sulphur as S. Os . . . . . . . . . . . . . 0.0680 X Potassium as K30 . . . . . . . . . . . . . 0.681 X) Sodium as Nas 0 . . . . . . . . . . . . 0.3325 X. Azote total . . . . . . . . . . . . . . . . 1.2196 ..) In vacuo and in a sterilised tube, fish frozen by immersion in liquid air at –1800 C, regained its normal consistency and appearance in 25 mi- nutes, as the meat did. In a sterilised tube in which no vacuum had been made, the same fish, frozen at –180° C by liquid air, regained its normal consistency and appearance at the and of an hour and a quarter, exactly as the meat did. After remaining 10 days at 0° to + 4° C the fish was examined. Smell of purtrifaction as well in the centre as on the surface; the outside was covered with a sort of creamy slime, the appearance at the centre was normal. Examination under the microscope. Bacteria in profusion in the in- terior in the form of short lines, Lines resembling Koch's Bacilli, not to speak of cocci. On the outside, a true pure culture of bacteria, still more than on the meat, with enormous numbers of diplococci. Chemical Analysis. The 100 grammes of fish were reduced to 90 grammes, a loss of 10"/o. Extract after dessication upon a stove at 100°C until weight became constant . . . . . . . 9'0935 grammes Chlorine as HCl .01251 grammes in place of 0.3536 X. PhosphorousasP, O, 0.5352 > » x > 0-6345 X. Sulphur as SOs . 0.0571 X). » x > 0-0680 X). Potassium as K2O 0.4243 X » x > 0.6081 X. Sodium as Nag O O'4019 X X » 0-3335 X Azote total . . . 1'1568 X. > x > 1°2196 X X I only worked upon 90 grammes of fish but all these figures are given as based upon 100 grammes of substance. There is, from this, a decrease in the total weight of chlorine, azote, phosphorous, potassium and Sulphur. There is, against this, an increase in that of sodium. - Examination of 100 grammes of fish which had remained for 3 weeks at 0° to +49 C. - * *- This fish had kept its white colour almost normal in the interior, for the outside was covered with a yellowish slime. The odour of putrifaction was much less at the centre than on the outsides. 377 - The whole mass contained bacteria in considerable quantities, resem- bling those observed at the first examination. The samples of fish frozen at —180° C and subsequently exposed for 3 weeks in sterilised tubes, exhausted or not exhausted, were not in a better state of preservation, and gave forth an odour of putrifaction while keeping their normal appearance and colouration in both cases. Bacteria resembling those which develop on fish exposed to free air. Placing these bacteria in soup made of sterilised beef and then placed on a stove at 37° C, as in the case of the meat, gave cultures of microbes. of an extremely unpleasant smell the first days, then towards the eighth day the soup gave forth a smell resembling that of an apple. The soup was uniformly turbid; cocci in profusion, isolated or in groups, complete absence of lines as in meat. - - * - Just as in the case of the meat, I injected the microbe cultures into some rabbits, 5 c. c. in each animal, and this inoculation did them no harm. whatever. Fish placed in a receptacle containing free air and at a temperature of 0° to +4° C, surrounded by ice, commencod to putrefy towards the 5th or 6* day, and gave out after a time, a nauseating odour. Milk. Ordinary milk was used for these experiments. Physical Characteristics. Appearance: translucent, normal. Smell: normal. Taste: pure. - Specific gravity: 1-033. Reaction: slightly acid. Microscopic appearance: absence of bacteria. Chemical composition : Water . . . . . . . . . . . . . . . 895.3 grammes per litre. Extract dried at 95° C . . . . . . . . 137-7 X) X X. Butter . . . . . . . . . . . . . . . 355 X) X > Sediment . . . . . . . . . . . . , 6.9 X X XX Caseine . . . . . . . . . . . . . . 330 X X X. Lactose . . . . . . . . . . . . . . 5037 } X, X- The same milk after remaining at 0° to +49 C days. Appearance: normal. Specific gravity: 1-033. Smell: normal. Taste : fresh. Reaction: acid. Microscopic appearance: presence of bacteria (lactic ferment). 378 Chemical composition: Water . . . . . . . . . . . . . 903:40 grammes per litre. Extract dried at 95° C . . . . . . . 129'60 X) * > . Casein . . . . . . . . . . . . . . 34:00 - x X X) Butter . . . . . . . . . . . . . . 32.90. X. K X- Lactose . . . . . . . . . . . . . 52:30 » . * > Sediment . . . . . . . . . . . . . 7:10 * X X There is then, an increase of - The acidity due to the presence ot lactic ferment, water, caseine, lac- tose and sediment; and a decrease of the dry extract and in the butter. The same milk after remaining at 0° C to 4° C for 3 weeks Physical characteristics: -- *- Appearance: normal. Density : 1035. Odour: normal. Taste: fresh. Microscopic appearance: presence of bacteria (lactic ferment). Chemical composition: - * Reaction: acid. Water . . . . . . . . . . . . . . 894-60 grammes per litre. Extract dried at 95° C . . . . . . . . 150-70 X X X Caseine . . . . . . . . . . . . . 3200 X. X X Butter . . . . . . . . . . . . . . 45:30 X « » Lactose . . . . . . . . . . . . 45'90 X X X Sediment . . . . . . . . . . . . 6:20 X X X By comparison with ordinary milk there was an increase in the acidity, the dry extract and in the butter; and a diminution in the caseine, the lac- tose and the sediment. * The same milk after remaining at 0° to 49 C for 10 days, having been frozen at — 180° C by liquid air. Physical characteristics: Appearance: normal. Specific Gravity: 1:034. Odour: normal. Taste: fresh. * s Microscopic Appearance: bacteria of lactic ferment. Chemical Composition: reaction acid: Water . . . . . . . . . . . . . . 887:20 grammes per litre Extract dried at 95° C . . . . . . . 12310 X. X X Caseine . . . . . . . . . . . . . . 27.50 X } Yº Butter . . . . . . . . . . . . . . . . 32.30 » . X ». Lactose . . . . . . . . . . . . . . 4590 » X X. Sediment . . . . . . . . . . . . . 860 - X X 379 By comparison with ordinary milk there was an increase in the acidity and the sediment; and a decrease in everything else. The small proportion of butter shown above points to the fact that a part was left adhering to the walls of the tube containing the butter in one case, and in the other case that the quantities which have been worked upon are very small. - The same milk after remaining at 0° to + 4° C for 3 weeks, having been frozen previously by means of liquid air at — 180° C. Physical characteristics: Appearance: normal. Specific gravity: 1:015. Odour: normal. Taste: fresh. Microscopic appearance : lactic ferment without any other bacteria. Chemical composition: reaction acid: Water . . . . . . . . . . . . . . 889:30 grammes per litre Extract dried ad 95° C . . . . . . . 12970 X X} X). Butter . . . . . . . . . . . . . . . 3350 X X X) Caseine . . . . . . . . . . . . . . 2800 X) X X) Lactose . . . . . . . . . . . . . . 48:22 X) XX X) Sediment . . . . . . . . . . . . . 7:30 X X X By comparison with ordinary milk there was an increase in the aci- dity (lactic ferment): and a decrease in all the constituents without exception and including a decrease in the specific gravity, but the taste remained normal. One more noteworthy statement to be made is that this milk appeared to contain, in all the different conditions in which it had been placed, ne bacteria other than those of the lactic ferment, it remained drinkable, and whatever changes were shown by the different analyses, were of but little importance. Butter. The estimation of moisture was made by the Bell process. Ordinary fresh butter: Moisture . . . . . . . . . . . . . . . . . . . 12% Substances insoluble in ether . . . . . . . . 4"/o Lactine and Caseine . . . . . . . . . . . . 3"|| Sediment . . . . . . . . . . . . . . . . . . 1"lo Fatty matter . . . . . . . . . . . . . . . . 84% After 3 weeks at a temperature of 0° to 4° C and still more after 10 days, this butter had kept its original colour, consistency, smell and taste. 380 From a chemical point of view no important modification was revealed except a slight diminution in the proportion of moisture, which became 10.5% instead of 12%. No bacteria either on the surface or in the butter. This same butter was completely frozen by immersion in liquid air at — 180° C and placed in a sterilised tube closed by means of absorbent cotton. Examinations were made 10 days and 3 weeks after it had remained at a temperature of 0° to 4° C. The two examinations did not show any important modifications as may be seen. - Moisture . . . . . . . . . . . . . . . . . . 8% Substances insoluble in ether . . . . . . . . 4°lo Lactine and caseine . . . . . . . . . . . . . 3% Sediment . . . . . . . . . . . . . . . . . 1's Fatty matter . . . . . . . . . . . . . . . . 84% Examination for bacteria, inside and outside: no bacteria. As can be seen this last analysis only differs from that of ordinary butter by the decrease in moisture, from 12"/o to 8%. From a morphological point of view this butter had preserved all its original qualities. Fruit. The question of the changes which take place in fruit, under the in- fluence of a cold temperature, requires a long chapter by itself and has been treated in an entirely insufficient manner, because of the season in which these investigations were made. Also it would be necessary to under- take it in its entirety in order to give it all the attention it deserves, regard. ing it as an article of consumption, and from the point of view of the industry connected with it. Evidently it would not do to freeze fruit by means of liquid air at — 1800 C. - Some fruit, grapes, some apples which had already been kept over, some oranges and tangerines, all of which I submitted to a temperature of from 0° to +4° C for 3 weeks, were unblemished on the outside after being taken out of the refrigerator at the end of 4 or 5 days, and after being left at the temperature of the room; but also, when these fruits were removed from the refrigerator, they had lost none of their original qualities either in exterior appearance or in flavour, moreover the estimation of glucose by Fehling's reagent, shewed no modifiation in the proportion of sugar in these fruits. These experiments should be repeated for each variety of fruit, and during the season when they are gathered. In this way it would be possible to arrive at conclusions which would be interesting and useful from the point of view of their consumption. 381 THE EFFECT OF LOW TEMPERATURES ON THE LIFE PROCESSES OF FRUITS AND ON THE RATE OF FERMENTATION OF CIDER. By H. C. GORE, Bureau of Chemistry, United States Department of Agriculture, Washington, D. C. Recent investigations by the Bureau of Plant Industry, U. S. Department of Agriculture, show the wide possibilities of the applica- tion of cold temperatures to fruits. The data show that cooling ef- fects profoundly their life processes. The question of how these processes are changed is of fundamental importance. The principal effect recorded by the pomologists is that the life processes which go on in fruits after picking, leading to over-ripeness and decay, are greatly retarded by cooling. It will be of interest to see how far data secured by chemical means accord with this view. The following review of chemical studies on the effect of cold temperatures on the physiological activities of fruits and on the rate of fermentation of cider is therefore presented. It is also hoped that this review may serve as a starting point for further investigations. Dr. W. D. Bigelow and co-workers’ studied the chemical changes occurring in apples at cold storage at 32°F. in comparison with the changes which occurred when the same apples were kept in common storage. Two series of experiments were carried on. - In the first series, 4 lots of apples of 4 barrels each were kept in cold storage for periods of about 19 and 20 months. After the fruit had been stored for approximately 2 and 5 months respectively, samples from each lot were removed and kept at temperatures of about 70°F. The apples in cold and in common storage were then analyzed at intervals and the relative rate of the changes in composi- tion during keeping at the two temperatures determined. In cold storage there was a slow loss in total solids, in total carbohydrates, in sucrose and in acid, while there was a slow increase in invert sugar due to inversion of sucrose. In common storage the same changes occurred except that they were much faster. Except in the rapidity * U. S. Dept. of Agri., Bur. of Chem. Bul. 94, “Studies on Apples”. 382 with which the changes went on, the character of the life processes did not change perceptibly, In the second series of experiments, in addition to the chemical changes studied in series one, the evolution of carbon dioxide by. the fruit at cold and at ordinary temperatures was measured. The Cold storage == Cellar temperature -------- Fig. 1 —Chart comparing results of analyses of Ben Davis apples used in respiration experiments. and kept in cold storage and at cellar temperature (total solids basis). analytical results of the first series of experiments were pratically duplicated. It was also shown that apples in cold storage evolved carbon dioxide much more slowly than at ordinary temperatures. An idea of the character of the changes which occured at the two tem- peratures may be had from the analytical data shown in Table I and É *ABLE 1.-Analysis of Apples used ºn respiration experiment, - BEN DAVIS AT CELLAR TEMPERATURE, * - * * IICTOSè. * Date of Total Acid as Sucrose Reducing | Total Weight Increase of carbon tº & º Starch, a & Sugar | Sugar as tº 4 analysis. solids. malic. By polar- | By inver-|asºrt | ºri. of apples: dioxid. b ization. Sion. 4 º 1902. Per cent. | Per cent. | Per cent. | Per cent. Per cent. Per cent. | Per cent. Grams Grams Per cent. | Per cent, Oct. 20 15.40 . 71 W.J., a 6.14 10. 17 | . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nov. '7 14.88 .421 .00 3.02 3.01 6.81 9.98 16,020 43,651 0.2725 0.2725 Dec. 1 14.14 .448 d .02 2. 12 1.88 7.34 9.31 12,940 39,197 .3029 .5754, 1903. r - Jan. 5 13.80 .394 | . . . . . . . gº o tº c 1.82 1. 55 7.62 9.28 11,125 24,367 . 2191 .7944 Jan. 27 13.85 .409 . . . . . . . . . . 1.44 1.37 7.33 8.77 9,670 10,190 , 1054 . 8998 Feb. 16 13.76 .887 | . . . . . . . . . . 1.28 1.17 7. 16 8.39 8,250 11,081 . 1343 1.0341 Mar. 2 13.02 .328 . . . . . . . . . . c 1.10 .90 7.62 8, 57 7,020 6,167 .0879 1.1220 Mar: 18 13.78 .341 . . . . . . . . . . .79 .836 '7. 69 8.57 5,430 8,599 . 1584 1.2804 Mar. 30 12.58 .345 ||---- 1.005 1.04 6.82 7.92 4,180 3,985 ,0953 1.3757 Apr. 14 13.59 .338 1. . . . . . . . . . .89 .58 7.43 8.04 3,135 2,218 ,0708 1.4465 Apr. 28 13.33 .863 |. . . . . . . . . . .69 . 74 7, 31 6.09 | . . . . . . . . . . . . . . . . & e º a e s tº e º 'º º ºs º º gº e º & e º 'º º 1901. Oct. 20 15.40 0.630 d 0.71 3.89 3,83 6.14 10, 17 |... . . ſº a w tº e a 4 e º a tº tº a tº º * * * * * * * * * * | * * * * * * * * * * 1908. | Jan, 5 14.61 . 596 | . . . . . . . . . . 2.96 2.83 6. 60 9, 63 17,800 41,664 0.2341 0.2341 Jan. 27 15. 13 .656 | . . . . . . . . . . e 3.34 2.98 6.83 9.96 16, 170 11,979 ,0741 .3082 Mar, 2 14.21 .506 | . . . . . . . . . . 2.45 2.25 7.09 9.46 14,900 19,070 . 1280 .4862 Mar, 31 14.09 .430 . . . . . . . . . . 2.02 2.30 6.89 9.23 13,565 6,568 .0484 .4846 Apr. 28 14.27 . 395 ! . . . . . . . . . . 2.19 1.92 7. 19 9.21 |. . . . . . . . . . . . . . . . . . . . . . . . . . © º ſº tº º 'º * * * * * * * * May 26 14.67 .425 | . . . . . . . . . . 2.10 1.81 7.06 8.97 l. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . * > * * * * * June 15 14.50 .885 | . . . . . . . . . . 1.89 1.68 7.32 9.09 |. . . . . . . . . . . . . . . & e - e º s a e º a tº º * * * * : * * * * * * * * * e Sept. 21 13.47 .269 . . . . . . . . . . . . . . . . * * * * * 2.88 5.88 8.90'. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • * * * | a starch determinations reduced by 0.5 per cent. b The figures in these columns show the weight and percent age of carbon dioxid formed between dates of analysis. of the total carbon dioxid formed up to the date of analysis. e Not used in calculations. * - a .32 ºz. . BEN DAVIS AT 0° c, (32° F.) c The figures in this column show the percentage d Starch absent after this date. 384 from the chart (Fig. 1), in which the analyses made at intervals dur- ing storage, together with the carbon dioxide evolved, are given graphically. The analyses in the table show that during storage at 32°F. for I62 days (from Oct. 20, 1901 to Mar. 31, 1902) there was a loss in total solids of I.31 per cent (15.40—14.09) or 8.5 per cent of the original total solids present. This loss consisted mostly of acids and total carbohydrates calculated as invert sugar. During this period there was a loss in carbon dioxide equal to .4846 per cent of the weight of the apples and to 3.15 per cent of the total solids. During storage at cellar temperatures at about 70°F., during practically the same in- terval of storage (161 days), there was a loss in total solids of 2.82. per cent (15.40—I2.58) equal to 18.3 per cent of the original solids. This loss also consisted mainly of acid and carbohydrates. The total carbon dioxide developed amounted to I.375 per cent of the fruit or to 8.9 per cent of the solid matter. From the changes in composition of the solids of the apple dur- ‘ing cold and common storage, shown graphically on the chart, an idea may be had of the relative rate of change under the two con- ditions of temperature. The acid decreased gradually in both cases and more slowly in the apples at cold temperatures. Total sugar gradually decreased but increases occurred in the invert sugar owing to the inversion of Sucrose. The rates of inversion of sucrose and of formation of invert Sugar were less than half as fast in cold as in common storage. A similar difference occurred in the rate of evolu- tion of carbon dioxide, and the rate of formation of this gas by fruits therefore appears to be satisfactory measure of their physiological activity. This determination had not been used before in a study of this kind, but later F. W. Morse' carried on experiments with apples kept at different temperatures, using the rate of evolution of carbon dioxide as a measure of the fruit. His results confirm the data obtained at the Bureau of Chemistry and “show that at summer temperatures apples undergo respiratory metabolism from 4 to 6 times. as rapidly as in modern cold storage.” Investigations of chemical changes during the cold and common storage of peaches have been made at the Bureau of Chemistry". In this work the chemical changes during the cold and common storage of five varieties of market ripe peaches were studied. In all cases. storage at 32°F. caused marked retardation. * J. Am, Chem. Soc., 30, 876. * & º 385 These data from the chemical side accord with the pomological evidence in showing that the principal effects of cooling consist in retardations rather than in derangements of life processes. More determinations of the rate of evolution of carbon dioxide at different temperatures are greatly to be desired as this appears to be a satis- factory measure of the physilogical activities. The study of the cold storage of cider” was made because at pres- ent in the United States Chemical preservatives are used in the market- ing of cider in the unfermented state. Aside from objections on hygienic grounds, the preservatives change the flavor of the product, and although alcoholic fermentation is much retarded there is often serious deterioration in flavor owing to the activities of other organisms than yeasts. If the cold storage of sweet cider is developed on a com- mercial scale, it will be possible to place upon the market a product whose character can be maintained practically unchanged over a con- siderable period. The report which is preliminary in nature, shows that sweet ciders, prepared from apples free from decay, chilled rapidly to the freezing point immediately after pressing, and then held in cold storage at 0°C. (32°F.) remained without noticeable fermentation for a period of from thirty-six to fifty-seven days, an average of fifty days for the Tolman, Winesap, Yellow Newtown, Ralls, Gilpin, and Baldwin varieties, and of eighty-three days in the case of the Golden Russet, Roxbury Russet, and Kentucky Red. These ciders were held for a period of from ninety to one hundred and nineteen days, an average of ninety-nine days for the first six varieties and of one hundred and twenty-five days for the last three, before they fermented sufficiently to be considered as becoming “hard” or “sour”. They were found to have suffered no deterioration (with the exception of the Tolman), but rather had become more palatable during storage for the periods mentioned. The investigation is of particular interest in connection with the study of biological processes during cold storage, Normal alcoholic fermentation occurred in all cases. The sugar was destroyed very slowly and alcohol gradually formed in amounts practically correspond- ing to the losses in sugar. In the cold storage of ciders, therefore, as in the application of cool temperatures to fruits, the effect of cooling is to cause retardations of life processes rather than abnormalities. * U. S. Dept. of Agri., Bur. of Chem. Bul. No. 97, “Studies on Peaches”, by W. D. Bigelow and H. C. Gore. * U. S. Dept. of Agri., Bur. of Chem. Circular No. 48. 386 THE EFFECT OF COLD STORAGE UPON BACTERIO – LOGICAL AND CHEMICAL CHANGES IN MILK AND BUTTER As Revealed by Laboratory Investigation in the United States. By DR. CHAS. E. MARSHALL, * Michigan Agricultural College, East Lansing, Mich., U. S. A. In presenting a cursory and semi-popular review of the investiga- tions conducted in the laboratories of the United States for the purpose of determining the influence of cold temperatures upon micro-organisms and their changes, the writer is confronted by the limitations which are placed by the work reported. However, what investigations are avail- able, demonstrate conclusively and establish several points of vital inter- est to the cold storage man, and to those interested in the preservation of the foods under consideration. At present we can consider only (a) the influence of cold storage upon the growth or multi- plication of micro-organisms. (b) the significance of species of micro-organisms involved in low-temperature development. - - (c) the changes . bich take place in milk and butter when Subjected to cold storage conditions. A fund of evidence, although limited, is contributed by Conn,’ and Esten", "Pennington", "Sayer, Rahn and Farrand", "Ravenel, "Hastings and Hammer", "Rahn, Brown and Smith", "Rogers and Gray", "Gray and McKay”, "Rogers”. . "—Conn, Bulletin 26, Storrs Exp. Station, 1903, Storrs, Conr. *—Conn and Esten, Rept. Storrs Exp. Station, 1904, Storrs, Conn. *—Pennington, Jour. of Biol. Chem. Vol. IV, p. 353, 1908. *—Sayer, Rahn and Farrand,-Tech. Bulletin No. 1, Mich. Agric. Exp. Station, 1908, East Lansing, Michigan. *—Ravenel, Hastings and Hammer, Jour. Inf. Diseases, Vol. VIII, No. 1, 1910. *—Rahn, Brown and Smith, Tech. Bulletin No. 2, Mich. Agric. Exp. Station, 1909, East Lansing, Michigan. "—Rogers and Gray,+Bulletin 114, Bureau of An. Industry, U. S. Dept. Agric. Washington. *—Gray and McKay, Bulletin 84, Bureau of An. Industry, U. S. Dept. Agric. Washington. *—Rogers, Circular 146, Bureau of An. Industry, U. S. Department Agric. Washington. 387 The results of these investigators have such an intimate relation that the one supports the other in many details, thus adding much force to the investigations as a whole. In reviewing the work, the plan just outlined will be followed. The Influence of Cold Storage Upon the Growth or Multiplication. -- of Micro-Organisms. - A graphic illustration used by Conn represent the development of a single bacterium at two temperatures,- one representing the number coming from this single cell at Io°C. in 24 hours, the other the number coming from this single cell at 21°C. in 24 hours; a designates the single cell; b, the development at IO’C.; c, the development at 21°C. The development at Io"C. is five-fold, the development at 21°C. is seven hundred and fifty-fold. * , s-ºvii º Sº § \, *.N. tº Y " vi VN §§- Jºi itſ N J / / \\\\ s's yºrs NY -\t TV / 1* (f iſ a a / N' W. 'Y, U.S. §§ \\\\{}\\ 'i,\\ "1 5 '''S \\? N I s—" f tºº. !ºsº, 'S','º','º', 2\ SSSYYYY º' W),\SY' 'º',' N \,\;x& ~ : 1 \ ...) \\\\\ '1N \,\", \\2S ZSZ, 1 J \ \\ Y ſ J * - ? ~ \ .T * * * > . ,< \T ~ \\\ – º s N - , }\!'...º.º. ) "," St) * \, \ SS MAN". | N * , "I 22's Vºs’ \'>\ i-, -\\\ – S-, v i l’i º Zººt N\ –," SV = N \,\! \\,\ iſ CZ. t"- > * * * N S. - 1 N- J N \ |\ , \ \l / S_S : 1 "-T 1 - WY F. N \}, N "1". \; \; - > li "Sº 1 \\\ \"\\\\ \\\\\", \}}\\! \ll \", \"\S SS - \\\\ \\ k\,\\ * *ASNNYº I SSS) * 2,1}\ u_*\'l Nº Tº sº. R A • V (1", ;’ Fig. No. 1. Conn and Esten have carried on extensively investigations which have sugggested the of value certain temperatures for inhibiting the growth of bacteria. They have employed in one series the temperatures of 37°C., 20°C., IO'C. In another series the temperatures of 20°C., Io°C., I*C. in other words, temperatures at intervals ranging from body temperature to the freezing point. A sample of milk is divided into three parts, one part is held at 37°C., another at 20°C., and another at Io°C. The growth of bacteria at different temperatures mentioned furnishes an index to the situation. The sample held at- 37°C. increased during 16 hours from 48,000 to 792,000,000 20°C. 6& €4 36 “ & & “ to 992,000,000, ----, 10°C. & & “ 216 “ & & “ to 1,460,000,000 & Another experiment of an almost identical nature yields results which run parallel with the above. 25% 388 The germ content increased in the milk held at- 37°C. from 5,700 to 600,000,000 in 16 days. 20°C. to 727,000,000 in 36 hours. 10°C. to 927,000,000 in 144 hours. In the second series of tests offered by these same authors, the tem- peratures range from I*C. to 20°C. The number of bacteria in- creased from— 24,300 to 346,000,000 in 16 days at 1°C. to 796,000,000 in 172 hours at 10°C. to 208,000,000 in 36 hours at 20°C. showing that there is a decided bacterial increase at all of these tem- peratures. Without considering further the temperatures of Io"C and 20°C., because they already have illustrative results, let me further pursue the studies at I*C. In another sample, the number increased from— 66,000 to 679,000,000 in 42 days 24,300 to 730,000,000 in 40 days In other words, I* above freezing in no sense inhibits the mul- tiplication of micro-organisms. Pennington has shown that market milk, when held at I.67°C to O. 55°C., increases in 42 days from— ,” 736,000 to 3,400,000 (plates maintained at 37°C.) 720,000 to 915,000,000 (plates maintained at 20°C.) 103,800 to 697,500,000 (plates maintained at 20°C.) In another sample of market milk held at 1.67°C to 0.55°C., from— 118,333 to 3,875,000,000 (plates maintained at 37°C.) 102,000 to 3,200,000,000 plates maintained at 20°C.) 70,000 to 885,000,000 (plates maintained at 0°C.) In a sample of clean milk, the increase was from— 7,200' to 2,730,000,000 (plates maintained at 37°C.) 4,516 to 3,970,000,000 (plates maintained at 20°C.) to 7,100,000,000 (plates maintained at 0°C.) It is evident, therefore, that there is a considerable increase in the germ content when either market milk or clean milk is held at tem- peratures ranging about the freezing point. One other feature develops in connection with Pennington’s work, which should be noted, lest some misinterpretations arise. The deter- mination of the number of organisms present seems to be greatly in- fluenced by the temperature at which the plates used in these determina- tions are held. The apparent discrepancy must be found, therefore, solely in the influence of the temperature upon organisms developing in the plates. 389 * In milk, there are various types of micro-organisms — some de- veloping at one temperature, others at another. With conditions, such as would enable the use of a pure culture, or, in other words, a single species, the results which have just been given would doubtles become quite uniform, In the investigations of Ravenal, Hastings and Hammer, two tem- peratures were employed for storing milk, o’C. and —9°C. Two classes of milk were considered,—dairy or market milk, and barn milk, a much higher grade or clean milk. The sample of dairy milk, held at O’C., increased its germ content in 160 days from- • 130,000 to 32,650,000 (plates maintained at 37°C.) to 94,500,000 (plates maintained at 12°C. to 15°C.) The sample of barn milk held at o°C., increased its germ content in 160 days from— 3,500 to 3,610,000,000 (plates maintained at 37°C.) to 191,500,000 (plates maintained at 12°C. to 15°C. Ravenel, Hastings and Hammer confirm apparently the results of Conn and Esten, and Pennington. In considering the samples of milk held at —9°C., much interest is aroused, because this temperature means frozen milk. The germ content of the dairy or market milk decreased in Ioë days from— 130,000 to 63,750 (plates maintained at 37°C.) - to 65,000 (plates maintained at 12°C. to 15°C.) The germ content of the barn or clean milk decreased in the same time from- 3,500 to 1,950 (plates maintained at 37°C.) to 3,200 (plates maintained at 12°C. to 15°C.) It is evident from this that the germ content falls when a milk is frozen. In milk, therefore, the number of germs increases as milk Stands, even down to the freezing point. Below the freezing point of milk and the milk is frozen, the number of organisms decreases. It is also apparent that as the temperature rises from O’C., development is more active, until 21°C. is reached. Above 21°C., the increase is somewhat variable, depending upon the predominant organism. Against the data covering the action of low temperatures upon the germ content of milk may be placed the results secured from a study of the influences of cold storage upon the germ content of butter. Doubtless, in the case of butter, other factors creep in to influence the germ increase and decrease of the germ content, but we shall be obliged in this instance, to assume simply that the numbers are influenced by no other agent. 390 / I employ the work of Sayer, Rahn and Farrand. The number of bacteria found in a gram of butter, designated as “Lot II”, is given as follows: - Total number when fresh is 26,046,000 6 months later when stored at +5°C. is 20,100 —7°C. is 972,300 —10°C. is 541,200 —5°C. is 759,300 - 9 months later when stored at +5°C. is 8,500 —7°C. is 309,800 —10°C. is 421,200 —5°C. is 665,500 3. From this, it will be seen that in all cases, there was a decrease in the number of bacteria, with the greatest decrease occurring in the sample held at +5°C. This may be due to the influence of temperature in enabling the organisms at +5°C. to develop and produce products in sufficient quantity to not only inhibit their growth, but to actually kill them off more rapidly. At lower temperatures, these products would not develop so rapidly; consequently, would not interfere with the life of the organisms so seriously. Inasmuch as the above citations are taken from a good sample of butter made under good creamery conditions, I desire to add the results of another sample, designated as “Lot XIII”, made under bad creamery condition. Total number when fresh per gram is 15,067,000. 6 months later when stored at -|-5°C. is 156,600 —7°C. is 3,013,900 —10°C. is 2,519,000 —5°C. is 1,688,000. 9 months later when stored at +5°C. is 64,500 —7°C. is 1,019,600 —10°C. is 1,740,800 5°C. 1,020,500. Throughout the twenty-eight lots of butter, there is recorded this same general reduction in the numbers of micro-organisms in butter above and below o’C. The reduction is greater in the butter held at higher temperatures than that held at lower temperatures. Taken in connection with the changes which take place and which will be dis- cussed a little later, this uniformity of results is quite significant, although it may be difficult to ascribe the exact cause. It is patent, however, that the harmony with preceding work is maintained fully, notwith- standing discrepancies which are noticeable and doubtless which are due to other factors already intimated in the foregoing. . i 1 S 391 Rogers and Gray contributed some determination of germ content of butter held in storage at different temperatures. These were con- cerned with butter made from unpasteurized and pasteurized cream. Each lot of cream, whether pasteurized or unpasteurized, was divided so as to have butter produced from cream— churned sweet - over-ripened starter added . normal ripened We shall limit ourselves to a study of butter made from unpasteur - ized cream, ripened normally, where a starter was added, and over- ripened. The total germ content per gram of butter when fresh was 3,- 924,OOO. -- When ripened normally After 6 months held at * —23°C. the germ content was 1,257,750 —12°C. the germ content was 1,107,500 - --|- 0°C. the germ content was 349,825 After 9 months held at —23°C. the germ content was 949,000 —12°C. the germ content was 1,026,000 + 0°C. the germ content was 211,000 The total germ content per gram of butter when fresh was 2,- 893,OOO. When the starter was added. . After 6 months held at —23°C. the germ content was 872,000 —12°C. the germ content was 730,000 + 0°C. the germ content was 531,000 After 9 months held at - —23°C. the germ content was 906,000 - —12°C. the germ content was 351,000 *. +- 0°C, the germ content was 102,000 The interest in the over-ripened cream centers in the increase of micro-organisms in cold storage. - The total germ content per gram butter, when fresh was 9,825,000. Over-ripened cream, After 6 months held at —23°C. the germ content was 24,727,500 —12°C., the germ content was 1,470,166 - + 0°C. the germ content was 554,000 After 9, months held at * * * —23°C., the germ content was 1,187,000 —12°C., - no butter, & -- 0°C., the germ content was 1,240,000. i 392 * The results secured by Rogers and Gray conform in large part with those which have been reviewed priorly, thus establishing two general facts: I. Micro-organisms continue to multiply in abundance in milk until the milk freezes, when there is no further increase but rather a de- crease corresponding to that of micro-organisms in ice. Ia. The number of micro-organisms in fresh butter corresponds to the maximum development; moreover, those conditions which fur- nish most rapidly the maximum accumulation of microbial products in the butter will hasten most the reduction of numbers. Accordingly, butter kept at high temperatures shows a greater falling off of numbers than butter kept at low temperatures, but it is possible for any specific organism at any time to take up a fermentation which has been eom- pleted and carry it to greater extents in other directions; yet this is not COmm On. 2. Micro-organisms in milk increase more and more rapidly from O°C. to 20°C. Above 20°C., they may or may not increase more rap- idly. Micro-organisms when frozen in ice do not multiply, but, on the other hand, many die as time passes. The Significance of Species of Micro-O rganisms Involved in Low-Temperature Development. We enter now upon the consideration of the kinds of micro-organ- isms involved in these studies, and especially those which are found at low temperatures, for, if multiplication occurs at the low temperatures stated, we are especially interested in the species which will develop. Conn and Esten attempt to group the Organisms involved in their studies, classifying them after the following manner: Group I. Bact. lactis acidi (Leichmann-Esten.) Group II. Bact. 1actis acidi II. Group III. Bact. lactis aerogenes. B. coli communis. Group IV. Neutral bacteria. * Group V. Yellow bacteria. Group VI. Rapid liquefiers. Group VII. Slow liquefiers. Group VIII. Pale thin colonies. Group IX. Red brown colonies; Groups VIII. and IX. they regard as insignificant. In the treatment of organisms, “Group” numbers are used almost exclusively. To illustrate the general conclusions reached by Conn and Esten, I shall draw from several of their experiments figures which will support them. It should be remembered, however, that there are devia- tons from these general conclusions which are very striking, such for 393 instance, as the greater development of the lactic types at I’C. than the neutral type. The authors realize and grant that no general law holds true, for so much depends upon the original germ content. In analyzing these groups, those who may have some difficulty in interpreting the meaning of each may keep in mind that Groups I and lf represent the typical souring of milk without gas production; while Gloud III yields a curd that is not so firm and there is an abundance of gas The neutral bacteria, Group IV, produce little change. Groups VI and VII are very important, because of their power to digest milk. º -*. Ul +3 # * : rº; 3 * | * , § - § 3 C Q) $– : Wy }*- ſº 60 U2 tº P. E 3. § 5 5 A3 9 g H . : 'E & 3 | *:::: H 3 E 3 || P. & tº £ g g i. $- G-l # - & * F-3 & H - ...l. P P •- U2 ſº P. to .3 c. P. to o, 2 2 : 0) Q,& Gº -> +–2 Q) 5 : "º q) - --- 5. - + --> : q) E is gº G} 8 § 53% . o + O Q c p <3 C E 6 º o rº Q) •g- : &H 7. $– § 3- Gº à ad & 3- C' : ; c. & H H 53-5 Ö SS ty- Özſº Ö - C5 ſº 3 B 1° C. 42 days | . . . . . . . . . . . . . . . . . . . ... 274,000,000 || 325,000,000 13,000,000 67,000,000 .......... 100 C. § 168 hrs, 119,000,000 : . . . . ....... 44,000,000 i 304,000,000 185,000,000 47,000,000 166,000,000 200. C. 36 hrs. 377,000,000 108,000,000 || 124,000,000 | 84,000,000 3,600,000 | ........... 93,000,000 37 o C. 16 hrs. J . . . . . . . . . . . . . . . . . . . . . . . 569,000,000 j . . . . . . . . . . . 3,100,000 | . . . . . . . . . . . . . . . . . . . The above table will illustrate in a single instance the dis- tribution of organisms according to the grouping of Conn and Esten at the temperatures of 1°C., Io"C., 20°C. and 37°C. It will be gathered from this review that the lactic bacteria develop best at 20°C., the gas and curd producing types at 37°C., the neutral types at IO*C., and I*C. with a very good sprinkling of liquefiers or digesting micro-organisms ranging over nearly the entire field, but held in check always by acid production. Pennington indicates that acid producing organisms are more nu- merous in milk held at o°C. than the liquefiers or digesters, yet the num- bers of lactic organisms are less than develop at higher temperatures. It is also evident from her work that the number of liquefiers may at times exceed in number the acid producers. This may be illustrated by her figures. ^*. Experiment V, Table IX, gives the milk a germ content at 35 days at O’C., 2,730,000,000 (37°C. plates), of which 1,200,000 are acid pro- ducers and 535,000,000 liquefiers, while in some glass containers Table XV, Sample 7, shows a germ content of 18,000,000, of which the acid organisms number 2,000,000 and the liquefiers 14,200,000. This last determination was made at the end of 14 days. sº As to the specific types which appear to dominate in the end in mill: * * 394 field at o°C., the author speaks of B. formosus, B. solitarius, and B. Ravenel. These organisms seem to be very resistant to cold, and to exist almost in pure culture at the close of the experiment. Some scat- tering types persisted as B. cloacae, B. pinotus, Bact, aerogenes, B. coli, et cetera. There are suggestions that types of torulae, and yeasts were present. - As far as species of micro-organisms are concerned, there is still available for consideration the extensive work of Sayer, Rahn and Far- rand with butter. The conditions of life in butter are somewhat differ- ent than in milk, but the results may be of comparable interest. The de- termination of species was given much attention, and every effort made to identify by means of the classification of Conn, Stocking and Esten. The following table in which the organisms are arranged according to their frequency will give the significance of each species best: 1 Lactic acid bacteria...... 157 times in 20 lots. 2 Small irregular yeast............. * - - - - - - - - - - - - 127 times in 20 lots. 3 Micrococcus lactis varians (71-4–13) 84 times in 16 lots. 4 Streptothrix ... 46 times in 18 lots. 5 Oidium lactis 44 times in 20 lots. 6 Penicillium glaucum............................ 44 times in 14 lots. 7 Bacterium lactis Connii........................ 38 times in 16 lots. 8 Aspergillus glaucus 30 times in 16 lots. 9 Micrococcus lactus aureus................ 27 times in 10 lots. 10 Rapidly liquefying yeast.................... 26 times in 11 lots. 11 Bacillus lactics cochleatus................ 18 times in 6 lots. 12 Pink yeast * * 17 times in 7 lots. 13 Round yeast ‘…. 16 times in 10 lots. 14 Micrococcus lactis albidus................ 16 times in 11 lots. 15 Bacterium lactis lobatum .................. 11 times in 3. lots. 16 Bacterium lactis album 9 times in 7 lots. 17 Bacterium lactis Gorinii.................... 9 times in 4 lots. 18 Maltose yeast ... 9 times in 4 lots. 19 Bacillus lactis Pruchii 8 times in 3 lots. 20 kinds with ~ ....... 736 cultures 20 lots. Besides these more frequent organisms we found 35 different kinds ** 1 times 35 cultures. 14 different kinds 2 times 28 cultures. 3 different kinds ... 3 times 9 cultures. 7 different kinds 4 times 28 cultures. 5 different kinds ---- 5 times 25 cultures. 3 different kinds.......................................... 6 times 18 cultures. 67 different kinds..... - 143 cultures. . 20 different kinds :-------. --- 736 cultures. * 87 different kinds - - 879 cultures. 395 Considerable weight should be given to the statement that after six months storage the lactics and non-lactics are found to decrease in numbers at about the same rate, but after nine months storage, the non- lactics or the liquefying bacteria appear to increase. There is such a decided disagreement when these results are com- pared with those of Reinmann, Jensen and Reitz,” and these investiga- tors disagree so markedly with each other, that no conclusion can be reached other than there is a lack of uniformity of species. Since this same fact creeps out in the study of species found in milk at low temperature, it is safe to draw the tentative conclusion that no species are wholly responsible for growth and changes found under cold storage conditions; in other words, many are involved, all of which may or may not be instrumental in producing changes, and no individ- ual species are pointed out as specific in any particular alteration noted. The Changes Which Take Place in Milk and Butter When Subjected to Cold Storage Conditions. The changes taking place at different temperatures and in cold storage may be most conveniently considered under— - Acidity Proteid degradation Flavor and aroma. In the matter of curdling, Conn and Esten have obtained some in- teresting results at 37°C., 20°C., and Io’C. One sample of milk held at- - 37°C. curdled in 18 hours, curd tough and gaseous. ** 20°C. curdled in 56 hours. 12°C. curdled in 9% days. The work of Reinmann, Jensen, and Reitz was conducted at room temperature. Another sample of milk at- & 37°C. curdled in 160 hours. 20°C. curdled in 44 hours. . . . 10°C. curdled in 160 hours. At temperatures of 20°C., Io"C., and I*C., the same authors con- tribute the following—one sample of milk at- 20°C. curdled in 48 hours. 10°C. in 240 hours, became thick. 1°C. in 42 days, became somewhat thick. Another sample of milk at- r - 20°C. curdled in 40 hours. 10°C. curdled in 180 hours. 1°C. in 40 days somewhat thick. 396 Pennington finds the acidity at –1.67°C. to o.55°C.— of clean milk, of market milk, 7 days 15° 7 days 17° 14 “ 22° 14 “ 17° 35 “ 39° 21 “ 19° 28 “ 19.5° 35 “ 20° At the end of six weeks the clean milk was “perfectly odorless and its flavor was much better than that of the usual city milk, though it was not, by any means, equal to the original flavor of the clean milk.” “At the end of the fourth week, the market milk had an unpleasant, rather bitter taste,” “There were no indications of curding.” The fifth week intensified bitterness and a “distinct and unpleasant odor had de- veloped.” The changes in the nitrogenous compounds and the dissipation of casein nitrogen presents a most interesting phase. In clean milk, at the end of the fourth week only 35.5% of the total casein nitrogen remained. In the market milk there was even a greater degradation of casein nitroge, passing apparently to amino acids. This particular sample illustrates very satisfactorily the changes noted by Pennington. There is as a rule an increase of acidity, sometimes rising to a high degree. However, this high acidity does not necessarily mean curding, although a curd could at times be produced by heating. No uniform results were secured, consequently, the change in reaction and curding were subject to changeable factors. The changes in the casein nitrogen with the formation of such pro- ducts as caseoses, peptones and amido acids are of considerable impor- tance, indicating at least that decomposition or digestion is not inhibited by the temperature maintained in these experiments. *-2- It follows that with these variable changes in acidity and casein nitrogen, the flavors and aromas must be very changeable. It is strikingly pertinent to record the changes noted by Ravenel, Hastings and Hammer in connection with Pennington’s results. The percentage of acid in the dairy (market) milk held at o°C. mounted from— { .16 to .68 in the period from Sept. 6th to Feb. 25th. in the barn (clean) milk from .18 to .77 in the same period. & 397 But when this milk was held at —9°C. the percentage of acidity decreased— - \ in the dairy (market) milk from .16 to .10 in the same period. in the barn (clean) milk from .18 to .10 likewise in the same period. At both temperatures there was a gradual increase of soluble nitro- gen thus according with the work of Pennington. Also the flavor and aroma of the milk underwent change for the worse, even at –9°C. 8o %– •, o …” d *.e. Lº -T -69 unsalteº — Q -—T •. _-T -bo salt ed 2 o' :* lö0 lºo 2OO days Fig. No. 2. These investigators are disposed to attribute the changes occur- ring in the protein of the milk held at —9°C. to enzymic action, for the number of bacteria had dropped off as well as the acidity. With some variations, which may be explained when more work is contributed, butter in cold storage acts much the same as milk, as has been demonstrated by Rahn, Brown and Smith. In samples kept above o’C., the acidity usually mounts very rap- idly, especially is this true of unsalted butter. The above chart, representing averages of samples, illustrates the acidity in days of * 398 Unsalted butter held at +6°C. Salted butter held at +6°C. Unsalted butter held at —6°C. Salted butter held at —6°C. It is evident too that samples make a great difference, or in other words, the source of the cream or butter. Three samples of butter were employed, A, B, C. All conditions—production, cream, manufacture, creamery-rank these lots as follows: Ist in quality B. 2nd in quality A. 3rd in quality C. Looking at these lots from the standpoint of acidity production at temperatures of +6°C. and —6°C., the same grading appears to hold true. * | lov 9 4G _-T Lot 5 29 *::: 50 LOO 150 200 day a Fig. No. 3. The accompanying chart represents the average results of Sam- ples of . *. * - Lot C at +6°C. and —6°C. Salted. . -Lot B - - at +6°C. and —6°C. Salted. • , Lot A * . . . at +6°C. and —6°C. Salted. 399 2. When we compare proteid degradation or decomposition of these same lots and samples of butter with the charts which represent acidity, it is found that there is a great similarity so far as quality is concerned. The degradation of nitrogen compounds in the following chart is measured in percentage of amid nitrogen over a period of days. Aver- ages of samples of butter from lots A, B, and C– T - Unsalted butter samples held at +6°C. Salted butter samples held at +6°C. Unsalted butter samples held at –6°C. Salted butter samples held at –6°C. lox +62 unsalied —r-º- . 4 +6° salteº-l _smº" _-rº L–T - -T - r 2% 45% 2% 50 x 100 - 150 - 200 days 250 Fig. No. 4. When the three lots are compared as in the case of acidity, we find they take the same rank in quality. Showing that the percentage of amid nitrogen is greater in the poorer sample than in the others. We are led to believe, therefore, that acidity, nitrogenous degrada- tion, loss in flavor and aroma are due to variable agents in the milk which in turn give rise to the variable results not only at different tem- peratures, but at the same temperatures. 400 Probably these changes are the direct result of the enzymic action of micro-organisms whether growing or inhibited in their growth by freezing. The enzymes may be formed before the changes become appar- ent or at the same time. Freezing does not of necessity check com- 10% Lot C _--T 8% _^ Lot A-l 2 } lot B 6% _--T 4% x- ſº ** ~~ 2: "T -º-º-º-º- s 50 100 150 200 days 250 Fig. No. 5. pletely the action of an enzyme, while it may check completely the multiplication of the micro-organisms. It follows that— I. Milk and butter must be frozen to check completely the growth : of micro-organisms. - 2. Enzymic action probably is not completely inhibited by low, temperatures and freezing, or, in other words, there may be deteriora- tion in milk and butter even when frozen. 3. The effect of lower temperatures than these cited herein is not determined. t 401 The Application of Mechanical Refrigeration to the Preservation of Fresh and Salt Meat. By L. van Wanjenbergh, President of the Syndicate ,Union des Bouchers et Charcutiers de Bruxelles et l'Arrondissement“ (The Brussels and Suburbs Butchers' and Pork Butchers' Union), Administrator and Director General of the Refrigerating and Ice Making Plants adjoining the Abattoirs of the City of Brussels. The report which we have the honour to present will treat on the following points: 1. The cooling of meat immediately after slaughter. 2. The chilling of fresh meat for preservation for several weeks in its normal state. 3. Chilling meat for preservation before, during, and after salting. 4. The methods of cooling employed in the above cases. Before examining these different points, we would observe, that for the purposes of our calculations we have assumed the rooms to be perfectly impermeable and insulated according to the temperatures required. We would point out from the beginning, that for fresh meat, salt meat, and even frozen meat to be perfectly preserved, it is necessary to cool it immediately after slaughter, in order to avoid starting any decom- position which develops very quickly in hot weather. As a matter of fact, meat killed in summer keeps its natural (animal) heat for a long time. Tests made on an animal, weighing 350 kg, dead, at a temperature of 26° C. in the shade and, reduced to about 24° C. in the abattoir by air circulation, gave the following figures: An hour after slaughter the outside temperature of thin parts of the animal (skin) was about 26°C., while the interior of the larger portions (the thigh, sirloin, topside, and the parts under the shoulder) still indicated a temperature of 38°C. 5 hours after slaughter the interior parts were at 36°C.; after 6 hours they were at 351/." C. X 7 X X X X 35 X X 8 X X X > 34'ſ, X X 9 X X X. X 33°/2 X » 10 X X X X 328/ 4 ° X 11 X) X X- » 32 X * 12 X X X » 31 X 402 and continued to cool during the following night at a rate of about 1 degree centigrade per hour, until they were actually below the temperature of the Surrounding air. It follows that heavier animals would cool more slowly. The result is that the time necessary for fresh meat to cool naturally, is far too long, and that, under the influence of the temperature prevailing in the interior of the large pieces, infectious germs develop with astonishing rapidity. - A means must then be sought of obtaining more rapid cooling, and for this recourse must be had to artificial refrigeration. ! The freshly killed meat is first placed in a room where the tempera- ture is from + 6° C. to +8°C. (antechamber or > avant-frigoriférez), and it is observed that, after staying here an hour, the outside temperature of the thin parts of the animal is about 22° C., and that of the interior of the large pieces, 37° C., while on entering, these temperatures were 36 and 38'ſ." C. respectively. The test was carried out on an animal weighing 400 kilogrammes, dead. On continuing the test it was noticed that the temperature fell through 29 C. per hour, hence the temperature of the large parts of the animal would fall to 10° C. in 14 hours. It has also been observed, and this is important, that meat cooled rapidly after slaughter keeps fresh for a longer time, even if hung up in the butchery. In modern abattoirs, which have rooms for the preliminary cooling (antechamber) and refrigerating rooms for preserving the meat for several weeks, the different temperatures prevailing in the rooms are obtained from one and the same machine. This arrangement, however, has its inconveniences, and we shall show that it would be convenient, for the purpose of cooling the meat in the antechamber where it remains for 15 to 24 hours, to have a ventilator and cooler independent of the plant which cools the refrigera- ting rooms proper. * Contrary to what is customary in other countries where meat is killed every day, in Belgium, particularly in Brussels, it is only killed on certain fixed days, for instance Wednesdays and Thursdays for large cattle, and Fridays for heifers; while pigs and sheep are killed almost every day. This results in large quantities of meat being placed in the ante- chamber at one time. As this meat is placed therein at an average tempe- rature of about 30° C., and as it remains there for 15 to 24 hours, the temperature of the antechamber, which was from 6 to 8° C. at the beginning, rises during the whole period. The water contained in the meat evaporates, and causes the atmosphere of the room to become moist and warm. Now, in a system consisting of one plant only, this air is drawn in and flows through the refrigerator, mixing with the air therein. The tem- perature of the air in the refrigerator rises, as also its hygrometric degree and the preservation of the meat being stored, which up till then was nor- mal, is interfered with; the temperature of the meat in the refrigerator 403 rises, it absorbes moisture, and mouldiness is soon set up, and once the meat has become tainted, however much trouble is taken, it cannot be re- stored to its original healthy condition. - Since the brine shower is not necessary, as we shall shew further on, except for preservation over a long period, it can be dispensed with in the antechamber, and the air may be cooled by direct expansion. . Moreover, there is an objection to brine; in cooling the room it is diluted by mixing with the water vapour supplied by the abundant evapo- ration of the freshly killed meat, and it becomes necessary to add salt from time to time. The cooling of meat for preserving it in its normal state for several weeks. If it is to be preserved a long time, meat must undergo preliminary cooling in the antechamber immediately after it is killed. This cooling is effected in the manner just described. After it is placed in the refrigerator proper, where the temperature is + 29 to + 4° C. The hygrometric degree of the air in the rooms must be about 77. - The air in the rooms is cooled by drawing in cold air. The air coming from outside must therefore be cooled down and dried, until it is at the required hygrometric state, and purified to avoid microbes coming into contact with the meat. This is effected by passing the air through a shower of brine at a temperature of — 6 to — 7°C. The brine absorbes the heat from the air, retains the microbes which it contains and condenses the moisture. The cooling of the brine down to —6° C. is effected in special reser- voirs containing coils in which the liquid refrigerating gas is allowed to expand. Meat may be preserved under these conditions for several weeks. It remains perfectly dry, retains all its flavour and keeps its fresh appearance. When meat thus preserved is to be sold, there is one precaution to be taken, that is not to transfer it without transition stages from the tempe- rature of the refrigerator to that of the outside air (which may reach as much as 25 to 30° C. in buildings). It must be allowed to remain in a place having a temperature of + 8 to 10° C. (a butcher's ice room for ex- ample), in order to avoid the effects of the condensation caused by the con- tact of warm air with the cold meat. 26% 404 Refrigeration for preserving meat before, during and after salting. Meat which is intended for salting like all other meat, must undergo preliminary cooling in the antechamber. ~~ c Salting consists in immersing the meat to be preserved in brine at a temperature of from +2° to +4°C., the salting rooms being cooled by a cur- rent of cold air as described above, in the cases of the preliminary cooling rooms and refrigerator. This system of ventilating the rooms has the ad- vantage of clearing away all odours, and it is for this reason that it is to be preferred to a system of cooling by direct expansion, which is simplex to install. A precaution to be taken in Salting, is to avoid placing meat from outside or from the antechamber directly into brine which already contains meat which is well salted, because the temperature of the latter would rise, and there would be a risk of interfering with the success of the present and future processes. Therefore the meat must be allowed to come to the tempe- rature of the room before being immersed in the brine. Great care must also be taken to see that the temperature and den- sity of the brine remain constant. - The time of immersion depends upon the nature of meat. For ham, for instance, it is about 21 days. When it has been withdrawn from the pickling vats, the meat should remain in the salting rooms at a temperature of +2" to +4° C. during a period at least equal to that of immersion, in order to allow it to become well impregnated with salt. Meat thus treated keeps well for a very long time and retains a good flavour and appearance. Conclusion S. From the preceeding it follows that preliminary cooling immediately after slaughter is a guarantee of the good preservation of meat. That meat, which for various reasons can only be delivered for consumption several days after being killed, should be preserved in a refrigerator at a regular temperature in order to be kept in its normal condition. - The salting of meat, which used to be done in large quantities in winter and in cellars not artificially cooled, often gave disastrous results. Now, thanks, to the regularity of the temperature obtained by artificial cold at any time of the year, the salting of meat, which is a very important matter, can be done under better conditions and at any time. As far as the system of refrigeration is concerned, the different methods which we recommend are those which in our knowledge give the best re- Sults with meat. - -- In the interests of the consumer as well as in those of the dealer, we know of no better advice to the latter than to avail himself, at his earliest 405 ‘convenience, of artificial refrigeration, because it is the only means, especially during the warm seasons, which can regularly provide the low temperatures essential to the good preservation of meat. . Before concluding this report we consider it our duty to pay tribute to the inventors and builders of the first refrigerating plants, who by sol- ving the important problem of the preservation of meat have assured a hy- gienic supply to large centres of population; gratitude is also due to the governments which have subsidized and encouraged the study of this impor- tant matter. - - 406 The preservation of eggs by refrigeration. - By F. Lescardé, Engineer, Paris. At the time of the Congress, which was held at Paris in October 1908 and which so brilliantly inaugurated the era of refrigeration meetings, I had the honor to explain the methods used by me in order to obtain true pre- servation of eggs. - At that time I enlarged sufficiently upon these methods, not to have to emphasize them; I have also explained them at length in the volume that I have published under the title of >The Hen's Egg, its Preservation by Re- frigeration «, Paris 1908, Dunod and Pinat, Publishers. But I am happy, in support of my assertions, to communicate to the Congress two documents which confirm their accuracy. The first is an extract from the report of Mr. Vandervelde, the learned director of the public Laboratory of the town of Gand, which gives the result of the comparative examination that he made with eggs preserved by my process from April 1909 till November of the same year, and with new laid eggs. It runs as follows: Exterior aspect. I was unable to find any difference as regards savor and odor. The yellow looks the same in the preserved egg as in the fresh one. Chemical Examination. The inquiry bore upon the degree of Solu- bility of the albumen in the white of egg; the quantity precipitatable by the acids amounts to 9.15% in the preserved egg, and to 9.56% in the fresh egg. From the point of view of the process of coagulation, there is no difference to take account of. - Bacteriological Analysis. After sterilising the shell the latter was care- . fully opened for aseptic reasons. The culture tests made in gelatine at 20°C and in soup at 37.5° C showed that the samples were sterile. The cultures remained sterile from November 22nd, to December 6th, that is during 14 days observation. Thus the bacteriological qualities are negative, and the same as normal fresh eggs. * It is impossible to be more exact upon this matter. The second document comes from M. H. Everaert, engineer and dele- gated administrator of the 'Société anonyme pour l'Industrie du Froids at Courtrai (Belgium) these are the exact words of that report. »In connection with the communication made by Mr. Lescardé to the International Congress of Refrigeration held at Paris, 1908, I was engaged in assisting in opening cases of eggs which had been preserved for ten months by the Lescardé method, at Morlaix in Bretagne. •. 407 Having sought for several years to find a better method of preserving eggs by the usual refrigeration processes, I found, in spite of all trouble, the following difficulties: gº * - 1* The impossibility of preserving the delicate taste of an egg after four months conservation, an egg acquiring after that period, a stale taste. 2* The impossibility of avoiding one of the two following dangers: the egg becoming mouldy or void. As mould is the worst enemy, it is necessary, in order to avoid it, to keep the air in the refrigerating chambers relatively dry. In consequence of this dryness, the substance of the egg evaporates appreciably, and the air space in the egg enlarges, which finally causes mirage. This last characteristic, being also that of stale eggs, the sale . price of eggs preserved by the usual refrigeration method is not at all remunerative. Having had this discouraging experience, I was all the more Surprised to notice the perfect state of eggs preserved for ten months according to Mr. Lescardés process. The taste was absolutely that of the freshest egg, and the egg was quite full. - In consequence of this test, our society became the holder of a licence to exploit the Lescardé patents, and since 1909, we have made a trial according to the new method, the trial covering 250,000 eggs. We have proved that the process, worked out by M. Lescardé in all its details, is perfectly simple for industrial application. After 10 months preservation the eggs remained perfect as regards taste, and entirely full. They were sold as fresh eggs in our local markets, as well as in those of Northern France and England. Moreover their pre- served State after coming out of the cold chambers is prolonged in a per- fectly extraordinary way. - Thus some eggs which had come out of the refrigerator on October 21st were analysed on the 21st of the following November by Mr. Vander- Velde, director of the public laboratory of Gand, and a well known specialist in alimentary matters. **. - In comparison with fresh eggs, M. Vandevelde proves in his report that there is no difference to find from the point of view of smell and savour, and moreover the eggs submitted to his examination are sterile. Owing to the result obtained, our Society has enlarged its plant, and is preserving this year 1,000.000 eggs by the Lescardé process; and it intends also to increase this production gradually as its commercial markets become more important.< . - In view of these results, thus proved, I consider that the true preser- vation of the hen's egg is a thing absolutely obtained, and I am happy to present this solution to the Vienna Congress. º 408 An improved Method of Packing gutted fish for Transport and keeping it fresh and sweet for a long time. ge By A. Sölling, Commissioner to the Danish Gouvernment Fisheries Departement, London. As a Member of the International Congress of Refrigeration I should like to bring before the Congress my method of packing fish for trans- portation and for keeping it fresh and sweet after a lengthened period. During my experience at sea it was forced upon me the extreme difficulty of keeping fish fresh by means of the use of ice, as, whilst the ice kept the temperature low, the ice water destroyed the quality of the fish, making it soft and sodden. e I, therefore, turned my attention to the work of devising a scheme whereby fish might be transported in a fresh condition. After many experiments I have been able to obtain a paper, which is water and air proof, and when used in conjunction with ice, does not inter- fere with the cooling properties of the ice upon the contents. I devised the method of taking the fish when caught, immediately cleansing them by severing the gills and gutting, preventing the blood from congealing and taking great care in the washing, using salt water; afterwards wrapping the fish separately in the paper, and laying ice around the exterior. Thus I was able to keep fish for many days and perfectly fresh. For instance on one occasion I took 3 halibut weighing about two stone each, packed them according to my method in Grimsby, and despatched them to Copenhagen. For the sake of comparision a fourth halibut was included in the same box, but was not wrapped in paper. - * Thirteen days afterwards the first halibut was taken out and I was informed (not being there myself) that the halibut was found perfectly fresh and without any discolouring of the skin at all. The halibut which had been laid down without being wrapped in the paper, and therefore remaining in direct contact with the ice, was discoloured on the skin, and perfectly stale; 12 days after this the second halibut was taken out, after being wrapped up for 25 days, and, in the presence of several gentlemen and myself, the flesh was found to be quite firm and white, and after being cooked it had retained its full flavour; 6 days after — 31 days in all-he third halibut was taken out and was found to be white and the skin not discoloured. It was tasted by several people — myself included — and was found to have retained its full flavour. This experiment is but one of many that have been performed by me and all equally satisfactory. I might mention that in Drontheim, where my method received a gold medal at the Fisheries Exhibition in 1908, two salmon, one gutted and 409 the other not, were wrapped in the paper and put in ice, and two other salmon, one gutted and the other not, were packed in direct contact with ice. After 7 days the fish were taken out and examined. It was found that those which had been wrapped in the paper hat retained their full brilliance on the scales, the full colour of the flesh, and the natural flavour, whilst the two fish which had been in direct contact with the ice had lost their sheen, and the flesh was pale, soft and stale. I wish to draw particular attention to this fact; that it is essential that the articles for preservation should be thoroughly cleansed, and they must be quite fresh when using the paper; otherwise my method is of no avail. The wrapping has no qualities for res to ring lost properties to st a le m at ters. It is as I have already stated intended chiefly to keep from the fish and meats the deleterious influences of air and ice water. I had the pleasure of demonstrating before the Premier of Newfound- land, Sir Edward Morris, when here about 12 months ago. He invited me to the Colony where I went and explained my method, experimenting on a cruiser during October of last year; also I demonstrated before the Board of Trade at St. John. The results were eminently satisfactory. I am glad to be able to report that the prospect of the Fishing Trade in the Colony has greatly improved since the introduction of my method. On leaving St. Johns for England I took a box of cod wrapped in the paper on Nov. 2nd on board the steamer. On Nov. 16" the box was opened, and the cod when cooked was found to be in excellent con- dition, firm and fresh, which quite confirmed what I had claimed for the method. In a certificate signed by the Captain, Purser, and all the passengers, it was stated that KShips not having cold storage equipment would find this preservative paper a boon, not alone because of the great saving in expense, but also from the greater satisfaction to the passengers». The paper has been experimented with in nearly all countries shipments having been made to Japan and India, in which latter place very good results have accrued. *. Reports recently to hand from the Government Officer in charge of the Fishery Enquiry in Eastern Bengal and Assam shew the complete and remarkable success of the process. It should be noted that the temperatures prevailing when the experiments were made were exceptionally trying, and such as are not met with in more temperate latitudes. One of the experiments was conducted in Dacca in Sept. 1909, when the temperature in the shade was 93 to 87 F, and the Officer in charge reported that the experiment had proved an unqualified success, and all that is claimed of Captain Söllings Wrapping has been demonstrated. Fish was kept perfectly fresh and full flovoured, with the flesh as if newly killed, for a period of 23 days by being wrapped in this paper and laid in ice, whereas the «Control, fish, without the paper, became soft and flavourless. 410 I am pleased to bring this matter before the Congress because it will mean that Fish will become more and more a better and healthy food when treated in this manner, as by reason of the long journeys the trawlers are now compelled to take, delivery to the markets and the consumer of freshly caught fish is more or less an impossibility, but the use of my Wrapping will greatly benefit the trade by attracting a larger public because of the greatly improved quality and freshness of the article. Trawlers on the East Coast of England are using the paper in the fishroom pounds, and whilst every fish is not actually wrapped in thee sheet great benefit is received as a result from putting firstly ise, then laying a sheet of paper, then the fish and another sheet of paper to cover tham and more ice, a further sheet of paper, and so on, keeping the ice water from the fish, as well as the germ-laden air, until the cargo of fish is discharged. An experiment has been tried of sending lobsters boiled in Canada to London. After being boiled and cooled the lobsters were wrapped in the paper and sent in cases with ice, and as a result retained their flaveur for about 14 days. I would mention in conclusion that my method of packing in fish- wrapping paper need not be limited to fish alone, but also meat will keep splendidly durind the hottest weather when wrapped up in the paper when perfectly fresh and laid in ice. - To ensure success all that is necessary is to use this Specially Prepared Wrapping Paper and to follow the directions given in this pamphlet. The following is the best method of gutting fish as used for English Markets: The Sole is taken in the left hand, the white side upward, and the knife is carried under the gill cover, outwards and down” s WartS. * * - - r *ss .* * A . . . . . . . . FOR TURBOTS & BRILLSS... . The Fish is laid down during gutting. The knife is carried under the gill cover, between the gill bones, inwards and downwards. 411 ... -- HALIBUT. To be gutted after the line X. PLAICE. The Plaice is taken in the left hand the knife carried across the fish as shown by the line X. t COD AND HADDOCKS. The fish must be gutted as shown on the drawing to prevent water accumulating in the belly. Application of Cold in Public Dairy Management. By Franz J. Kaiser, Director of the Vienna Dairy. From the earliest times ice and cold have played an important rôle in the milk trade. The easy decomposition of milk, which makes itself at once noticeable by Sourness, as soon as the milk is exposed for a fairly long time to warmth, must always have made it appear necessary to keep the milk cool during storing and for this to make application of cold in some form or other. No less necessary is the application of cold during the processes of making various milk products, as, for instance, in earlier times, before the centrifugal system was introduced into milk technics and when the cream was obtained in primitive fashion by skimming, it was necessary to provide for the maintenance of the milk within certain maxi- mum temperatures, in order that the success of the process of obtaining the cream might not be jeopardised. Therefore it was necessary, in the Holstein process of obtaining the cream, to arrange suitable cellars in which the milk could be placed for creaming. To avoid too great warming during the summer, huge walls, up to one metre in thickness, were made use of and further assistance was sought in the application of ice. Nevertheless the by-products especially were lost by this process, the exhausted milk rapidly soured, and especially in summer, was generally unfit for cheese making. For these reasons the process of the Swedish land-owner Schwarz gained great importance for lean cheese making. The milk was placed in specially constructed vessels for creaming either in running, cold water, or better still in water cooled by ice. Cream and skimmed milk were thus obtained quite sweet and this advantage outweighed to a great extent the loss of value through less effective results. Still more important did the application of cold become on the introduction of cream separation by means of centrifuges. In order that the product might not be harmfully affected, this process required that the milk should be warmed before the centri- fuges were used, and the great advantage of this method, the obtention of the two products cream and skimmed milk in completely fresh state, only resulted if the milk was thoroughly cooled, it being advisable to use ice, 413 immediately on being obtained. The use of ice and low temperatures in the dairy and butter trades is now general, and especially in those countries in which dairy farming has attained to the highest perfection, as in Denmark and Sweden, and also in North Germany, the production of artificial cold with the aid of special machines has attained to great use. It gained, however, no lesser importance in municipal dairy arrangements. By the growth of large towns milk delivery has become as difficult a matter as it is important, for not only must milk often be drawn from remote districts, to meet the growing requirements, but the lasting quality of the milk and its products undergoes ever greater demands from the time of delivery until it is consumed. If the municipal milk Supply is to be effected in a faultless manner, especially during summer, a chain of conditions must cooperate to bring the milk to market in a Sweet, lasting condition and to place it in such condition at the disposal of the consumer. The requiste measures fall into (a) the obtention of the milk and its storing till despatch, (b) the transport to the town; (c) the handling of the milk after arrival in the town until the time of delivery to the consumer, and finally, (d) the handling thereof on the part of the consumer in the household. Of the greatest importance for the maintenance of the milk in fresh state is the thorough cooling immediately after the milking process. As is well known a rapid and thorough cooling can only be accomplished with the aid of a cooling machine, and that the cooling water used is frequently, and always if great demands will be placed on the lasting quality of the milk, brought down to the required temperature with the assistance of ice. For short transport, quick consumption or in sending over short distances the use of fresh spring water for cooling the milk may be sufficient, it is true. But under conditions such as exist especially in the supplying of large towns, where the consumption of the milk often does not take place until 36 hours after its obtention and even later and it is mostly impossible to avoid re-warming during this time, the use of ice cannot well be dispensed with, at all events not in summer. The cooling will have to be all the more intensive, the higher the temperatures to which the milk may be subjected during transport and indeed during the whole of the time that elapses before its consumption, so that a despatch of milk in southern towns, among which in the first place Vienna must be reckoned, is absolutely unthinkable without sufficient cooling with the assistance of ice. After the cooling, the milk, if not immediately despatched, will have to be stored for a short time, and for this suitably arranged milk store-rooms must be used. At country dairy-farms, so-called natural ice has hitherto been almost exclusively used. This can usually be obtained by the farmer at lesser cost, than the application of artificial ice. The ice is usually gained at a time when pressing husbandry work has not to be undertaken, so that it is often quite opportune for the farmer to be able to suitably employ his 414 labour. Nevertheless, cases occur in which mechanically produced ice must be employed, especially when mild winters make it impossible to obtain sufficiently large supplies of natural ice, or when from other causes clean and hygienically blameless ice is not at disposal. This has, as is well known, been the case this year in many places, and larger dairies have actually had to be provided with refrigerating machines. Such machines serve chiefly only to cool the water necessary for the cooling apparatus, or to cool the water in a cooling basin; they are less often put up for the cooling of rooms or manufacture of ice. The transport of the milk from the place of obtention to the town is effected to-day most generally in a very primitive manner, and it cannot be doubted that in the course of the coming year a-great improvement will take place here. The present despatch of the milk is not at all rational; at the railway stations at which the loading of the milk takes place, there is at present an entire want of the most simple arrangements to protect the milk against the effect of the sun rays, to say nothing of cold warehouses, which, at least in those railway stations at which the milk despatch centres, would be very necessary. The use of refrigerator cars on the railways for forwarding milk consignments has until the present time only been tried in single cases, so that larger experience in this point is not available or at least has not yet become generally known. At the present time as regards municipal milk Supply, importance is in the first place attached to rapid forwarding, the undelayed delivery of the consignments on arrival at the railway station at the destination and also to the consideration of certain hours of day for milk transport, while the views regarding the necessity of refrigerator cars have not yet been explained at all. This may partly be due to the fact that the advantages which the use of refrigerator cars would introduce are but little known in the milk trade circles and have for the most part only met with theoretical interest. But this circumstance may be principally due to the fact that those concerned have not yet come to an agreement concerning the production of ice and the dividing of the expenses. Nevertheless the development wich milk supply has undergone in large towns during late years shows that in the near future the general introduction of refrigerator cars will be indispensable. Whereas formerly the cool stores in the towns or the farmers in the immediate neighbourhood covered the milk requirements entirely or for the greatest part, to-day far the greatest quantity of the milk destined for consumption is brought by means of rail- ways and that often from the most remote districts, so that transports of 100 Kilometres and over are quite general. In Vienna, for instance, the daily consumption of milk in the old nine districts was about 130,000 litres forty years ago, of which only 48,000 litres, that is 37 per cent was carried by rail. The requirements of to-day, in the enlarged town are put at 820,000 litres, of which about 680,000 litres, or nearly 83 per cent, are sent by rail. A still greater and increasing consumption of milk in large towns 415 may be anticipated with certainty for the future, because the requirements increase, according to experience, not merely with the increase of population, but also relatively, and it may be merely mentioned that the quantity of milk consumed in Vienna per head per day of the population for forty years has risen from 2 to 4 litres, that is it has exactly doubled. This increase in the consumption of milk, which as it should be repeatedly emphasised, still continues and has not yet, by a long way, reached its limits, often offers difficulties even at present, which make themselves noti- ceable partly in the rise in the price of milk, and necessitate the bringing of milk from ever greater distances. The dangers of the milk turning sour are however increased thereby, and all experts are aware of the fact that the setting in of a higher temperature may suddenly lead in a town to a serious lack of milk in consequence of its turning Sour and spoiling. Other circumstances too will make the cooling of milk during transport more necessary in future than heretofore. It is well known that milk is often pasteurised before despatch, for the sake of increasing its keeping power. Many as are the advantages arising to the whole milk technics from this ..procedure, yet it has certain disadvantages as regards hygiene, which occur in the case of unsuitable handling or storing of the pasteurised milk. To this must be added the increasing dislike, on the part of the public, for pasteurised milk which makes it appear equally necessary to secure the permanence of the milk in the first place by cooling and keeping cool. The statement that in most countries success is attained without refri- gerator cars, is in no way conclusive; reference need only be made to the claims of consumers regarding the condition of the milk, which besides the difficulties mentioned increase from year to year, and to the number of aids that are to-day necessary to a rational municipal milk supply which were also unknown in former years. Far more general than in sending milk is the use of refrigerator cars for butter transport during the warmer seasons. The advantages thereof are especially appreciated in Denmark, France, Russia and in part in North Germany. It may be mentioned that Denmark and Russia make regular use of ships provided with cooling apparatuses for the butter export trade, using refrigerators for this purpose while in railway cars the cooling is effected by ice which is generally placed in special vessels below the roof of the car. * If one follows up further the route of the milk sent by farmers to towns, it is seen that especially in the cases of large towns, this does not go direct to the consumers for the most part, but is first taken over by milk shops or dairies. Just according to the manner in which these manage the sale and delivery of the milk to consumers, they subject the milk to a further handling in their own locality, partly that it may satisfy all justifiable requirements regarding the condition, the taste, the permanence, and cleanness and other hygienic qualities, partly in order to make from it other products, such as cream of various consistencies, butter and such-like. 416 The application of cold here, forms a very considerable help, which for cooling the milk warmed in transport, or after the pasteurising centrifugal process, or in the storing of the milk and such-like is most necessary. The more perfect the fittings of a dairy business are, the more will it make use of this aid, and as it is just the refrigerators that are most suitable for producing the necessary low temperatures, as well as for many sided and reliable application, no less, further, on account of cleanliness and a manner of working that is free of hygienic objections, no large municipal dairy should be without a cold plant. These advantages appear important enough to cause refrigerating machines to be used even where, as in nor- therly lands, the use of natural ice may be cheaper. Naturally a cold plant only offers full advantages to a dairy if its position fully satisfies the requirements of the work, so that both its size must be suitable to various temporary requirements and also the cold must be available for the various methods of application. A considerable part of the cold applied in municipal dairies is used for cooling the milk, cream and skimmed milk, which is in general effected with the aid of the well-known cooling machines. It is especially worthy of note, that latterly, in cooling the milk as also in cooling the cream ever lower temperatures are sought and just the slow-coolings has the best reputation. According to experience milk so dealt with is not only more permanent, but is consi- dered to have a better flavour, which especially with the continual increase of direct consumption of the so-called 2 drinking milk is worthy of consi- deration. Low cooled cream tastes more full, and whipped cream may be better and more completely whipped, if it is subjected for a lorger time to very low temperatures. Low-cooling after the pasteurizing causes the frequently so objectionable cooking flavour to be less noticeable, and finally the opinion may be put forward, that the rapid and low cooling of the cream intended for butter-making after pasteurization increases the permanence of the butter. The question is often raised now as to the best manner of cooling milk in a refrigerating plant, whether this is done better with fresh water or with brine. The opinions on this point are very various. In general small businesses make use of brine cooling, if only on account of the simpler plant required, although this, on account of the rapidly changing tempera- tures requires constant and careful watching of the machine, and may also lead to considerable loss through possible leakage of the apparatus. For larger businesses, in spite of its more complicated installation, fresh water cooling will probably be preferred, while direct evaporation of the refrigerant in the apparatus will scarely become of general importance. Besides the application of cooling apparatuses, the cooling of rooms is also of importance for dairies. Every dairy establishement must have rooms at disposal in which the stock of milk and milk products may be stored until 417 final disposal. The temperature of these rooms must not exceed certain limits. Whilst in some, especially the smaller plants, this cooling is effected by placing the vessels containing the milk in cold or ice-cooled water (as in the milk rooms of the farmer), in other places the milk and milk products are placed in rooms which either have ice stored in them or are connected in some way with an ice house. For example, a room is divided by sheet iron on which ice rests, while the cool room is below. Cooling by means of a refrigerating machine with brine circulation, or direct air for larger establishments is preferable from a hygienic standpoint as well as for cleanliness. Besides the store rooms it will often ‘be necessary in Summer to cool those rooms in which butter is made, pieced or stored. Sour milk too (Joghurt milk), which thanks to the recommendations of physicians conti- nually gains in importance, requires the use of cooled rooms at certain stages of its preparation and finally — though this is of less importance for municipal dairies — some kinds of cheese, particularly white, are stored in cooled rooms. Regarding the cold rooms it should be noted that their position in municipal dairies must depend in the first place upon the working conditions, and they accordingly are advantageously placed near those rooms in which the manipulation of the milk is conducted, at all events they should be easily accessible. For many establishments several smaller cold rooms (so-called cold-cells) are more useful than a large room, and beyond this, in calculating the desired amount of refrigeration, consideration must be given to the fact that the cold rooms in dairies are very frequently entered, so that an influx of heat occurs to a far greater degree than in other industries. t A further manner of applying cold in municipal milk supply results during the sale and delivery of the milk or its products to consumers, whether by means of milk-carts or shops. In both cases the use of ice cannot be dispensed with in summer. Regarding the quality of the ice strict regulations are made, and with justice, concerning its cleanliness and sanitary condition. Municipal dairies with cold plants produce this ice (to advantage white) on the premises, and here many a simplification in working and a not inconsiderable saving of cost can be secured. About ten or twelve years ago the freezing of milk — the obtaining of the so-called ice-milk — was much heard of. It was believed that by this process the difficulties which the easy decomposition of the milk led to were overcome, and a revolution of the whole municipal milk supply was expected. First the permanence of the milk was to be indefinitely secured by the freezing. Thereby it was not only to become possible to bring milk, even during the hot season, from the most distant places, but also, by the aid of stored ice-milk, to overcome all variations in the supply and sale of milk in large towns throughout the year. Ice-milk never attained to a position of any importance in the municipal supply, and those establishments 27 418 which introduced the process by way of trial quickly recognized that they could attain their purpose by simpler and cheaper measures. First of all it must be stated that by the freezing a not inconsiderable deterioration in the milk was caused, further frozen milk is by no means secure against decomposition if kept for long periods, so that ice-milk, from this cause alone, is not suitable for the varying requirements. The bringing of milk from distant places could not be seriously considered for the good reason that, apart from the high cost of production, such must fall to the ground through the high freights alone, which latter, indeed, limit the district by which a town can be supplied with milk as it is. Later on the ice-milk idea was dropped and it was endeavoured to introduce the so-called "cold milks. This is milk cooled by pieces of milk-ice, whose disadvantages are indeed less than the before mentioned. In opposition to the endeavours to introduce ice-milk or cold-milk to the trade it seems to be much simpler to cool the milk to a low temperature before shipment and during transportation to protect it against re-warming by tising refrigerator cars. With such process it is neither necessary nor desirable tho freeze the milk intentionally, as the milk only loses in value if it is much changed either in its chemical or physical condition. From the above it is evident that dairies, and especially those engaged . in municipal supply, have derived considerable benefit from the application of ice and refrigeration, so that the advantages of the use of refrigeration are ever more and more justified. On the other hand it is desirable that the use of refrigerator cars for milk transport by rail become more general, and that milk producers and milk sellers come to an agreement with the directors of railways in this matter. The use of refrigerator cars for transportation of milk on railways during the warm seasons is likely to greatly facilitate supplying large towns with good durable milk. Milk producers and dealers and railway directors are therefore urged to agree regarding the construction and use of refrigerator cars. 419 New Application of Refrigeration in the Preparation of Concentrated or Solid Foods Especially Milk Powder. By Messrs. F. G. Lecomte and R. Loinville, Engineers at Dax (Landes). This new process, which differs totally from those hitherto employed, possesses advantages that will be appreciated by all agriculturists and dairymen on account of its simplicity and the absolute certainly of its results. - If the manufacture of concentrated milk or milk powder alone be con- sidered, the process in likely to be applied in future by all dairymen for preserving or carrying milk in the simplest form possible and reduced by more than three quarters of its original bulk in consequence of the Com- plete elimination of the water it contained. By this process, instead of heat, the various effects of which, both on the salts and on the fatty parts of the milk, are either objectionable or troublesome, refrigeration is employed. With refrigeration the water is crystallised and the salts or non-congealable solid parts are separated; that is to say, the formative elements of the liquid treated are extracted from the congealed mass by all suitable means: filtration, centrifugal foice, attraction, ejection, compression, as well as the rotatory freezing process. The application of the process, being extremely simple, is within reach of all dairymen, and can be employed anywhere, as the apparatus required with heat, such as stoves, evaporating chambers, etc., which are non-trans- portable and very costly, are not needed with refrigeration. In cold countries, the temperature is low enough to reduce liquids to freezing point, especially as the whole need not be frozen through. It suffices if the milk is frozen to the condition of snow, so as not to bind up with the mass the non-congealable parts. If the surrounding tem- perature does not suffice, the crystallisation of the water contained in the milk is induced by any well-known means; and to obtain a more complete separation in the subsequent operation it is advisable to keep the milk in *:::: 27s 420 motion when near freezing-point, or to reduce the solid mass to the con- dition of snow. * The crystals produced in this manner, containing nothing but pure water and holding the non-congealable elements, should then be placed in a suitable drying machine and subjected to centrifugal action, which causes the complete separation of the non-congealable elements that constitute milk and these are ejected in a coagulated state, the water-crystals remaining in the apparatus, -- Experience has proved that the non-congéalable parts thus separated re- present the whole of the constituant elements of milk and may be preserved as they are or subjected later, at the farm or the factory, to mechanical drying by any suitable means in order to obtain a more or less thick paste or, by prolonging the operation, a dry powder. - * The process may be applied both to pure or skimmed milk, as well as to any other liquids or food stuffs. º - 421 On the Importance of Refrigeration for Foods, with Special Consideration of Milk. . By Dr. med, vet. Hans Messner, Director of the Slaughter-house, Konsulent (Councillor) of the Ministry for Agriculture, Carlsbad. Of all kinds of food, the flesh foods especially are most subject to decay. This circumstance, as also the fact that flesh foods are of great importance, or better said, indispensable to mankind, led men to endeavour to preserve them for longer periods, even in the earliest times. Endeavours were primarily made in the case of the various kinds of animals slaughtered for food, and from the first these were crowned with some degree of success. The oldest method, the air-drying, was followed by pickling and smoking, and later by a long series of other chemical means of conservation and finally by the introduction of canning, which keeps foods good for long periods. All these methods, however, have a decided effect upon the texture and taste of the meat, and besides this, considerably limit the cook's chances of distinguishing himself. Besides these methods, which are principally chemical, men endea- voured to preserve meat by laying it directly on ice, or keeping it in rooms cooled by ice, and these methods are very much in use even at the present day. Apart from the danger of using ice that is not free from hygienic objections, this method has the well-known disadvantage, caused by the great amount of damp produced by the melting of the ice, that the meat soon begins to decay on the surface, so that even after a short time the outer layers are useless and must be removed by thorough scraping and cutting away, which loss naturally increases the cost of meat thus preserved. If the meat is kept thus for a longer period the whole meat gets an unplea- saht smell, due to the progressed superficial decay. True, by suitably adapting the store rooms by convenient placing of the ice, and by good ventilation arrangements success was attained in diminishing the amount of damp, but it was not possible, even then, to keep meat fresh for several weeks, to approach which is the ideal of meat preservation, which ideal I would describe as that method which makes it possible to keep meat for y 422. weeks and months, and without too great expense, so fresh and unchanged that in use no loss or only a very slight loss occurs and every manner of cooking is made possible. Under these circumstances it is easily explained that modern technics direct a good deal of attention to meat preservation. It is not my task here to describe thoroughly the development of the refrigerating industries and I would merely like to point out that at first people endeavoured to achieve the preservation of meat by freezing. It was only when this method proved not altogether suitable, especially for inland towns, that use was made of the method of preservation in air as dry and pure as possible and of at most + 2–4° C. This led to the introduction of cold stores, such as can be seen everywhere in use to-day, and the average success of these as regards the preservation of meat proved that the new direction was the correct one. I must leave it to greater experts do discuss the differences in the various systems and their value as regards meat refrigeration. From my own experience I can only say that I have had numerous opportunities of inspecting the plants of various systems and that wherever there were suitable and well managed plants the results were perfect. Whether carbonic acid, or ammonia, or sulphuric acid should be used depends in each case upon various circumstances, often local conditions; as regards their effect, namely the obtaining of a sure means of meat cooling, all three may be considered equal. Now that, thanks to the untiring efforts of our technical men, the problem of meat preservation may be considered as solved as regards its principle and apart from the continual improvements and perfections that may be awaited with certainty, I would like to describe it as the duty not only of leading men and the directly interested business circles, but also of all classes of the meat-eating public, to see that the greatest possible use is made of this gift of modern technics to the food industries. The numerous advantages of meat cold stores may be divided into two great groups, namely the industrial and the hygienic. The industrial advantages consist chiefly therein that the loss of meat, formerly so large owing to the primitive methods of preservation, has become very small, and further that the period of storage for the object in view, may be said to be almost unlimited and that it is now much more easy to make - use of favourable trade conditions. The hygienic advantages are partly the cleanliness of the manner of preservation which hinders the settling of . putrifaction germs and consequently the decomposition of the meat, partly too in the process of ripening that the meat can go through in cold stores without spoiling, and by which it greatly gains not only in taste but also in tenderness. An important advantage of the cold storage, and one highly to be recommended for sanitary reasons, lies further in the fact that storing of the meat in dry cold, as is the case in these stores, prevents the outward infection of the meat with pathalogic germs, for example the exciters of 423 the paratyphus or flesh poisonings, whereby the prevalence of such sicknesses is greatly reduced. With such a number of good qualities one would imagine that the number of cold storages would grow not only annually but daily. Such is not the case however. In Germany only about one third of the slaughter- houses are provided with cold storage plants, and in Austria this proportion has not yet been reached. Blame for this rests chiefly on the fact that in many places neither butchers, nor municipal authorities, and least of all the consuming public give the large attention and full understanding to the importance and value of meat cold stores which these justly deserve. It may be confidently hoped that the II. International Cold Congress will do much to an improvement in these conditions. To gain this end, especially to carry explanatory particulars into the widest circles of those it may interest, I would beg leave to suggest to the Congress that they publish and distribute gratis a notice paper, such as the well-known papers of the German Imperial Health Office. Such a paper must describe in short but clear form all the advantages of artificial cooling in use for the preservation of the various flesh foods, and should contain suitable data as to the manner and cost of erecting such cold storages, etc. It would also be very appropriate in these to refute and disprove all the objections against the introduction of artifical cooling for meat preservation, such as, especially during discussions on the erection of cold storages in municipalities, are constantly being put forward. For support of such action in favour of the erection of cold storage plants, however, the state authorities would in the first place and in the widest measure be appealed to. I believe the government, should the II. International Cold Congress put forward the petition, could procure con- sideration for this action in their remotest spheres of influence, and would do so to the best of their ability, because an increase of the number of cold stores for meat would be of great importance for the provisioning of the army in the case of an outbreak of war. I believe this support in the first place to be such that the municipalities should at every suitable oppor- tunity be reminded of the necessity for the erection of meat cold storages by the proper organ of the government, best therefore by the official and veterinary doctors. To this end it may also be further recommended that the Government have plans drawn up for such buildings, in the same way that they have already done in so successful a manner for slaughter-house buildings, on the basis of which plans discussions on the erection of meat cold storages could be more easily introduced and carried more quickly to a favourable termination, since with these plants to work upon in connection with the means at the disposal of the municipality a clear picture of the possibility of such a building would be given. Where the means at the dis- posal of a municipality are insufficient the possibility might be considered of several municipalities uniting in putting up a building, and this should result in a successful arrangement if a suitable site were chosen. Such cold 424 stores for several small municipalities in common would of course only occur in thickly peopled districts or where there is a large export of meat, and they would very advantageously be combined with abattoirs. With such centralization there would also be the hygienic advantage that the control of the meat in such stores would be made easier and safer, and further that this control could always be carried out by the veterinary experts whose first duty it would be. Such conditions too would facilitate the general carrying out of a regular examination of the meat in country places, as was planned by the Government long since. It would in the first place be endea- voured to erect such meat cold storages in such districts as experience shows regularly Supply the large cities, spas, and centres of industry of our Empire with meat. This supply is effected even nowadays in the most primi- tive manner. The meat is often despatched, from districts that may be very distant, in ordinary railway trucks, very likely without undergoing any suffi- cient cooling, certainly without ever being frozen. The state in which, under these conditions, the meat arrives and how much of the meat, or money, is lost by the spoiling of the meat will be best known by the veterinaries who are entrusted with the control at the various points of arrival. Even Vienna, the capital of our Empire, the meat conveyance to which seems to be best organised, is compelled every year to confiscate very considerable quantities of meat which arrive in a decomposed state. Thus in 1908 no less than 80,000 Kilogr. of meat were confiscated and destroyed for this reason. If the kilogramme be reckoned at but 1 Krone, this means a loss of 80,000 Kronen in one year to the nation. This loss was partly due to insufficient cooling before loading and partly to the primitive transportation facilities. The conditions of transport to Vienna are however, most favorable, there being 157 refrigerator cars for meat on the main route. If this were not the case, the loss during transport would be considerably greater. The other large towns, and especially those in Bohemia, receive their meat supplies in ordinary waggons the loss being accordingly much greater. All these losses must be taken into consideration by the business man in making his prices so that the prices of course rise very much. An extensive increase in the number of special waggons on Our railways is therefore an urgent necessity. The most important point, however, is to properly refrigerate the meat before the transport. The great value of thorough refrigeration before des- patch is best seen in the case of regular sendings. Carlsbad for instance draws large supplies of veal from Hannover every summer which, well chilled before despatch, arrive, in spite of the long way, in perfect condition, though packed in primitive fashion in cardboard cartons or wood boxes. It may be remembered, too, that veal is very subject to decomposition. It is hardly necessary to explain further that the railway companies should always send meat by fast trains. If the conditions of meat supply are such as to urgently require the erection of numerous cold stores, this requirement is still greater in the 425 . case of game and poultry, for these decay more easily. Especially do large quantities of game and poultry spoil during transport, through not being well refrigerated before loading. There would be no objection as regards in storages to be erected for meat, to arranging such with special facilities for refrigerating game and poultry, where local conditions make this appear necessary, or to providing the special rooms necessary for the preservation of these goods. How far such plant could be made further use of for keeping fish would be dependent upon local conditions and could be considered as require- ments arise. Having considered animal foods that may be classed under the general term » meatº, I would like now to draw attention to another still more im- portant animal food, namely 2 milk. Refrigeration plays a different, I think I may say, far more important rôle in the case of milk than in the case of meat. In the case of meat the necessity for refrigeration only occurs when the meat is to be kept fresh for longer periods or when it is to be trans- ported over long distances. In the case of milk one may say that the necessity for the application of cold arises immediately after the milking and must be continued, in consideration of the justifiable demands of modern hygiene and no less of those of the milk trade itself, until delivery to the consumer. Hygiene demands a milk as free as possible from germs, and the milkman and the consumer demand a milk as fresh as pos- sible, that is milk that has the least possible amount of acid. With healthy animals, clean stalls, rational feeding, and cleanly milking, the milk when first obtained contains but few germs, and if one is able to submit such germ free milk, as soon as possible after the milking, to a suitable energetic chilling process, and to keep it in this chilled state until delivery to the consumer, then one could easily satisfy the demands of hygiene and of both dairyman and consumers to the fullest possible degree, since such a procedure hinders the propagation of germs, even of the acid forming kinds. If as often happens in large dairies, the chilled milk received be subjected to a temporary heating (pasteurizing, sterilization) for the sake of making it keep longer, there can be no objection thereto provided the milk be again suitably chilled after the heating process. Where the milk is delivered from large dairies the conditions as regards chilling are favourable, at least from the moment of entering the dairy. The milk is often handled in a manner from the moment it is obtained until its delivery to the dairy, which is neither advisable nor suitable. It must be pointed out with the deepest gratitude that the provincial government of ‘Lower Austria, the first in Austria to do so, have endeavoured to lead up to the proper manner of collection and delivery, so important for the quality of the milk, by laying down sanitary regulations concerning the places where milk is collected. Styria has already followed the example of Lower Austria, and it is very desirable that the remaining crown lands should take similar action. - 426 I would like to point out, however, that the action of governments in this matter must remain limited to a certain measure for various reasons, and that the important matter of chilling the milk immediately or soon after it is obtained can only with difficulty be made a subject of general municipal work. In order that eventually all milk may be chilled immediately after the milking, we must in the first place endeavour to get the dairyowners to introduce it voluntarily on the strength of their own knowledge of the great value of such chilling ; and this end will therefore be most easily gained by means of a suitable organisation of the milk trade, wherefore the endeavours of landowners in this direction should he energetically en- couraged and supported. Such a re-arrangement of the milk trade according to modern hygienic methods would without doubt not only be much desired by the army of milk consumers and the government, which, indeed, as is well known, always has the regulation and insurance of the milk traffic at heart, but also would open to the landowner a favourable prospect of increased profit on his products, so that probably such action would meet with general Support. A detained discussion of such action would lead beyond the scope of this Congress, wherefore I must forego it. I mention it, however, since the very important assurance of chilling milk from the moment of obtaining it can in my opinion only be attained by means of such general organisation. The advantages of earliest possible and continuous chilling of the milk are So well known, that I will only give them very briefly here. They are partly hygienic and partly commercial. The hygienic advantage consists chiefly, Since by lower temperatures the propagation of germs is hindered, in keeping the milk in a germ free state, whereby the possibility of injurious pathological effects on the milk is considerably decreased. The commercial advantages are principally that milk so treated keeps fresh for a very appreciably longer period of time, and accordingly will stand longer trans- port, so that less loss arises through milk becoming bad, and what is especially important, supplies can be obtained from greater distances. I would beg leave, however, to remark that though the chilling is in- deed a most important factor in the modern milk trade, yet to obtain a hygienically suitable commercial article a whole series of other conditions must be satisfied, and from the chilling alone one must not expect to obtain a perfect milk. I make this observation in consideration of the sad experiences formerly had with sterilization or Pasteurization of milk. At the time when these methods of treating milk were introduced it was generally imagined, contrary to the actual conditions, that by these methods it was possible to make every milk perfect. No further attention was given to the health of the animals, to their fodder or to cleanliness in milking. The disastrous results of such neglect did not fail to discredit the whole proce- dure. Just as little as can sterilization or Pasteurization can chilling alone 427 (to give two examples) change a dirty milk into a clean milk or an in- fected milk into a perfect milk, though the chilling is able to keep a milk obtained in a cleanly manner from healthy animals much longer in its good natural state than it would keep under usual conditions. - If the chilling is to be effected at the place of production, then the farmer must be enabled to effect it in a simple and cheap manner. For the farmer himself or his assistants must carry out the process, which must be cheap both as regards the cost of working and the cost of plant, since milk is an article of commerce which will not bear great additions to the cost of production. Where are the milking stations of a village, favorably located, it would not be impossible, in the direction of the previously mentioned organisation of farmers, to have milk chilling apparatuses for common use, indeed, even to erect special milk cold storages; the latter, however, only in the case of large quantities of milk, and if they could also be made use of for preserving butter, eggs, etc. In general, however, the chilling would be conducted separately in each separate branch. And if we now ask ourselves whether simple and cheap chilling apparatuses, suitable for common use, are at the disposal of farmers for this purpose, we must say that such is not yet quite the case. In the great majority of cases the farmer endeavours to cool the milk by placing the vessels that contain it in flowing water, a process which only cools the milk gradually and slowly, and by which the temperature reached is not sufficiently low. Moreover in summer, the very time when a vigorous chilling is most necessary, this method very often fails altogether, since the water gets warmer. Milk coolers supplied with ice or freezing mix- tures, it is true, work very well, but they are still too awkward, and also somewhat expensive to keep up, for the often small trade of the farmer. Machinery plants for the purpose of chilling at the place of production come but little into consideration. I believe, therefore, that there is, here a praiseworthy task, equally important both economically and hygienically, the solution of which lies with our experts on cold technics, and it may therefore be to the purpose if increased attention is given to this question. I therefore beg to propose that with the object of forwarding the general introduction of milk refrigeration, the Second International Congress of Refrigeration offer a prize for such milk chilling apparatuses, as shall most Satisfactorily meet the requirements of the country milking stations, as regards effective work, simplicity and cheapness in cost of plant and of working. In order, however, to provide for the necessary cold storing of the milk during transportation, it may further be advisable that the Congress forward a memorandum to the government, as already mentioned in the case of meat, calling attention to the great importance of such a measure, and requesting that greater attention be given to milk tansport on rail- ways, So that especially where large quantities are carried, special waggons 428 may be used in which it may be possible to maintain the milk in its chilled state. - ^ Finally, so far as the management of the milk in shops is concerned, in all better class dairies and milk shops the milk is nowadays kept in iceSafes, and in my opinion the state and municipal authorities working together would not find it difficult to prescribe suitable methods of storing milk in shop, thus at the same time completing the cycle of milk chilling. By these means this most necessary and important food would rise in the position of a very much sought after necessary of life both on account of its palatable and digestible qualities. This would not only be beneficial to our Austrian farmers, but ought to be welcomed from the bottom of our hearts on account of the great advantages thus being obtained to the general nourishement of the people, especially of children. - C on clusions. I. Artificial Mechanical Refrigeration is still far less applied for the pur- pose of preserving animal foods than appears desirable considering its numerous advantages, equally important both from hygienic and eco- nomic standpoints. - II. To obtain an improvement in these conditions the II. International Congress of Refrigeration is required: a) To distribute in the widest circles a pamphlet setting forth in clear concise language all the advantages of artificial refrigeration for preserving the various flesh foods and giving suitable data as to cost, style, arrangement, etc. for the erection of refrigerating plants, also disproving all objections raised by opponents to the erection of cold plants. b) To request the government to draw the attention, at every possible opportunity and through the various departments, of the various industries affected and especially the municipalities, to the im- portance of erecting cold stores, and to support to the utmost all endeavours to this end. - III. It is of the greatest importance that milk be thoroughly chilled im- mediately after the milking or as soon after as possible, and that the chilling be continued till consumption. This applies to the quality of this most important of all foods both from hygienic and commercial points of view. Organisation of land management is in the first place requisite for the speediest possible introduction of this chilling. *. The I. R. Ministry for agriculture must be requested, by the II. International Congress of Refrigeration to, by Systematically educating the country population as to the advantages of chilling milk, pave the way for its introduction as a regular procedure, and to assist country organisations by means of subsidies in their efforts to obtain milk chilling plants. 429 IV. The II. International Congress of Refrigeration must, for the sake of furthering the general introduction of milk chilling, Öffer a prize for such milk chilling apparatuses as shall meet the requirements at the places of production in the country, in regard to great utility as also in respect, to simplicity of manipulation and low first cost Öf the plant and its working. V. The demands now almost daily made as regards keeping animal foods fresh and cool during transport, especially meat and milk on railways, are in the majority of cases not satisfied from sanitary and economic standpoints. The II. International Congress of Refrigeration, referring to these unfortunate conditions, must hand a memorandum to the I. R. Government and the I. R. Railway Ministry, urging that an increase in the waggonage, and especially of the Söcalled special waggons or cold-waggons, on the lines principally concerned in this traffic, may be effected as soon as possible. It should at the same time also be requested that the transport of animal foods in general be permitted by fast trains. 430 THE APPLICATION OF LOW TEMPERATURES TO THE CURING AND STORAGE OF CHEDDAR CHEESE. By DR. S. M. BABCOCK, College of Agriculture, University of Wisconsin, Madison, Wisc., U. S. A. Previous to the year 1860, nearly all of the cheddar cheese made in the United States was manufactured upon dairy farms each factory utilizing the milk of a single herd only. In consequence of inadequate facilities, unskilled makers and careless methods of manufacture, much of the cheese made at this time was inferior in quality and unsuited for the export trade. The most obvious defects were bad flavors, im– perfect texture and lack of uniformity a large part of which were a direct consequence of the improper methods employed in the handling and storing of cheese after it was made. The small farm factories were usually provided with curing rooms sufficiently large to hold the output of three or four months and some of them kept all of their cheese until the end of the sea- Son when it was sold to a single buyer. No special attention was given to the control of temperature in the curing or drying rooms, except possibly to warm them in the spring and fall when there was danger of freezing; at other seasons the temperature of these rooms closely approximated that of the outside air and ranged from about 50° F. in the early season to more than 90° F. during the summer months. It was generally believed that low temperatures, espe- cially when near or below the freezing point, were always detrimen- tal, at least during the early stages of curing. Even temperatures as low as 60° F. were supposed to injure the product by causing bit- ter flavors and a mealy texture. As late as 1863, the best known cheese experts of this country, Mr. L. B. Arnold and Mr. X. A. Wil- lard, both recommended curing temperatures ranging from 70° F. to 80° F. if cheese were to be marketed when six weeks old and not lower than 65°F. under any condition. The general extension of the factory system to all dairy sec- tions of the country, between 1860 and 1865, led to the adoption of 431 more uniform and improved methods of manufacture and at the same time to a greatly increased output of high grade cheese. The curing rooms at factories, however, remained for many years in practically the same condition as in the old farm dairies, no effec- tive means being attempted to control temperatures, except pos- sibly to warm the rooms when the weather was cold. The export of cheese increased rapidly in consequence of improved quality un- der the new system and there arose the need for large storage facil- ities at the shipping points; this was usually secured in cellars where the temperature was approximately 60° F. and it soon became evi- dent that the quality of mature cheese was retained better at this than at higher temperatures. This practice became quite general when large quantities of mature cheese were to be stored, but no cheese were kept as low as 60°F. until after they were thoroughly broken down and fit for consumption. It was not until between 1885 and 1890 that any cheese were placed in artificially cooled rooms, and no cheese were cured, from the press, at low tempera- tures until more than ten years later. In 1893 and 1894 an experiment was conducted by Major H. E. Alvord, then Chief of the Dairy Division of the United States De- partment of Agriculture, for the purpose of determining the effect of low temperatures upon the quality and loss of weight of mature cheese, when stored for considerable periods.” The experiment was conducted upon a commercial scale, about three tons of cheese con- sisting of cheddars, flats and young americas being used; these were divided into three lots which were stored at temperatures of 40°F., 34°F., and 28°F., respectively, for a period of eight months; they were scored by expert judges at the end of each two months. The quality of the cheese remained practically the same, throughout the whole period, for each variety and for all temperatures. There was, however, less loss of weight at the colder temperatures, for each variety of cheese. The losses, per 100 lbs. of cheese stored, for each lot is shown below. Variety Average Loss of weight, of cheese. weight. Composition. per 100 lbs. Water. Fat. 40°F. 34°F. 28°F, Cheddars.............. 68 lbs. 37.76% 32.64% 5.87 lbs. 5.12 lbs. 2.88 lbs. Flats.--------------------- 37.7 34.51 35.73 5.53 4.37 2.19 Young Americas 10.4 ........ ........ 9.34 6.95 4.25 These figures clearly indicate that losses are considerably di- minished by reducing the temperature at which the cheese are * Bulletin 83, Bureau of Animal Husbandry, U. S. Dept. of Agr. stored, the loss at 28°F, being less than half that at 40°F. in every case; it should also be noted that the loss in this experiment is very much less than is incurred when cheese are stored for the same length of time at temperatures above 60°F. Naturally large cheese should lose less in proportion to their weight than small cheese when stored under similar conditions, since the exposed surface from which evaporation occurs diminishes as the size of the cheese increases. The relative losses of cheddars and flats does not conform to this rule, but in the case of the young americas the losses were considerably larger than with either of the larger sizes. The relatively high loss of the cheddar type is un- doubtedly attributable to the higher percentage of water and lower percentage of fat in these cheese, since both of these factors tend towards a more rapid evaporation of water. *- One half of the cheese of each size were coated with paraffin before being placed in cold storage with the result, in every case, of greatly reducing the loss in weight without impairing the quality in any way. The losses of the paraffined cheese were as follows: -- Loss in weight, per 100 lbs. Temperatures 40°F. 34°F. 28°F. Cheddars t 3.19 lbs. 1.36 lbs. 1.27 lbs. Flats ..... 2.00 1.60 1.05 Young Americas * 2.38 2.11 1.45 In general, there was a decided advantage gained by coating the cheese with paraffin before placing them in cold storage. The cold storage of cured cheese was generally practiced among cheese dealers at this time (1894), but no attempt had been made to ripen cheese directly from the press at temperatures below 60°F. and it was still the universal belief that lower temperatures than this would prove disastrous by developing bitter flavors and imper- fect textures, if the cheese were subjected to them before they were sufficiently mature for consumption." The adoption of low temperatures, during the early stages of ripening, was undoubtedly delayed many years by prevailing no- tions regarding the nature and cause of the changes that occur. At this period, nearly all who were investigating these changes believed that they were primarily caused by the growth of micro-organisms (bacteria and molds) within the curd, and since the development of such organisms as are found in cheese are practically suspended at temperatures near the freezing point, it was a natural inference that such temperatures were incompatible with the normal course of changes required for the production of high grade cheese. This 433 idea is confirmed by persistent attempts of dairy bacteriologists both in this country and Europe to isolate from milk specific cheese or- ganisms and by the use of sterile milk, inoculated with such organ- isms, for cheese production to improve and control the flavor and texture of cheese. It was while engaged in investigations of this kind that Babcock and Russell, of the Wisconsin Agricultural Ex- periment Station, discovered galactase, the inherent proteolytic en- zyme of milk, to which, more than any other factor, may be attrib- uted the change in ideas regarding the nature of the curing process, which in turn led to tests by the same parties, of the influence of very low temperatures upon the quality of cheese. The first carefully conducted experiments to determine the in- fluence of temperature upon the changes that occur during the rip- ening of cheddar cheese of which any record was made, were under- taken by Babcock and Russell, at the Wisconsin Agricultural Ex- periment Station in 1895.” In these experiments, cheese were cured at approximately 50°F., 60° to 65°F. and 85°F. In all five series of experiments were conducted with different lots of cheese in each of which the curing process, as indicated by the amount of soluble proteids, proceeded more rapidly at the higher temperatures. On , the other hand, it was shown that the cheese cured at 70°F. and above were, without exception, inferior to those cured at 60°F. and below. All of the cheese cured at 85°F. had an open texture accom- panied by sharp and unpleasant flavors. The best cheese were those cured at the lowest temperatures. The cheese cured at 50° to 55"F. were all of exellent quality with a close, firm texture and entirely free from bitter or other unpleasant flavors. Soon after this work, experiments along similar lines were in- augurated at Iowa Agricultural Experiment Station**, in Can- adaš, and at the New York Agricultural Experiment Station, at Ge- nevaf, all of which confirmed the results at Wisconsin, the lowest temperature employed invariably giving the best quality of cheese, while at 70°F. and above there were developed unpleasant flavors and an open texture. In spite of these results, which were all favorable to the use Of much lower temperatures for curing cheese than had been previously recommended, no trials were made at temperatures below 50°F. until February 1899, when Babcock and Russell stored two cheddar * Annual Report, Wis. Agr. Exp. Sta., 1895. ** Bul. 57, Ia. Agr. Exp. Sta. § Annual Rept. Ont. Agr. College and Exp. Farm, 1900. f Bul. 184, N. Y. Agr. Exp. Sta. 434 cheese, directly from the press, at temperatures below freezing (25° to 30°F.) for the purpose of determining the lower temperature limit of activity of the new enzyme galactase. These cheese were kept - Cheese made with three ounces of rennet per 1000 lbs. of milk and ripened at 40°F. (lower cheese) and 60°F. (upper cheese). constantly below the freezing point for periods of 14 and 17 months, respectively. When ermoved they were found to be thoroughly broken down with an almost perfect texture, a very mild pleasant flavor and, to the surprise of all, no trace of bitter or other undesirable taint. _ 435 An analysis of these cheese when removed from cold storage, showed that the cheese 14 months old contained soluble nitrogen (albumoses, peptones and amids) equal to 29.1 per cent of its total nitrogen, while in the cheese 17 months old 30.4 per cent of its nitro- gen was soluble. These quantities are about the same as are found in three month old cheddars ripened at temperatures ranging from 60° to 65°F. It is notable that the lower decomposition products of casein, amids and ammonia, were present in much smaller quantities than in cheese ripened at higher temperatures for the same length of time. A bacteriological examination of these cheese when removed from cold storage showed that lactic acid producing forms and inert species were most abundant. Very few liquefying and no gas- producing organisms were found. A repetition of this experiment was begun in May 1900, in which cheese were cured at 15°, 33°, 40°, 50° and 60°F. In making the cheese used in this experiment, varying amounts of rennet extract (3, 6 and 9 ounces) per 1000 lbs. of milk were employed in order to determine whether an increase in rennet would not materially shorten the time of curing at low temperatures without injury to the quality. * > The cheese were examined by expert judges at frequent inter- vals, and chemical analyses were made when the cheese were 6, 10, 12, and 14% months old. The results of these analyses are as fol- lows: Percents of soluble nitrogen in cheese made with 3, 6 and 9 ounces of rennet per 1000 lbs. of milk and ripened at temperatures from 15° to 60°F. Age in Rennet months. used. 15°F. 33° F. 40°F. 50°F. 60°F. 0 3 OZ. .14 .14 .14 .14 .14 6 & 4 .56 .86 .77 .90 1.08 10 * {& .60 .90 ------ .99 1.16 12 “ ------ ~~~ 98 ------ ........ 14% {{ * .62 1.02 ------ 1.15 -------. () 6 Oz. .14 .14 .14 .14 .14 6 { { * - - - - - - - - - - - - .88 ------ 1.24 10 & 4 .63 1.05 1.07 1.11 spoiled 14% 6 & .87 1.16 -------- 1.27 -------- () 9 OZ 14 .14 14 14 14 6 * {{ .70 .95 1.18 1,0S 1.65 10 {{ .74. 1.13 1.27 1.26 spoiled 12 “ … -------- 1.56 -------- -------- 14% & 4 .95 1.40 -------- 1.78 -------- It appears from the above that the rate of ripening increases with the ripening temperature. It is of special interest to note that even below freezing, at a temperature supposed to inhibit bacterial growth, there is a considerable increase in soluble proteids. It is also clear that the soluble proteids are much more abun- dant in those cheese made with an increased amount of rennet. This increase was confined wholly to compounds characteristic of peptic digestion, which had been previously shown to be produced by the pepsin contained in the rennet extract.* It is probable that the milk from which these cheese were made was of poor quality for cheese production, since cheese made with a normal amount of rennet (3 ounces per 1000 lbs.) and cured at Cheese made with three, six and nine ounces of rennet per 1000 lbs. of milk and cured at 40°F. (lower cheese) and 60°F. (upper cheese). 50° to 60°F., conditions which should have resulted in first-class cheese, were defective in both flavor and texture. In spite of this handicap, the cheese made with 3 ounces of rennet and cured at 33° and 40°F, were at the end of the experiment of excellent quality with an almost perfect score. The cheese cured at 15° and 33° F were all poor although the quality was improved when 6 and 9 ounces of rennet were used. These results apparently contradict those ob- tained in the first trial, in which normal cheddar cheese ripened for the same period at temperatures below freezing were of excellent quality. If, however, as surmised above, the milk used in the last | trial was defective, the poor quality of cheese cured at the lowest | temperatures should be ascribed to this factor rather than to the in- * 17th Rept. Wis. Exp. Sta., 1900, p. 102. 437 fluence of low curing temperatures. It is also possible that slight modifications in the methods of manufacture may have influenced the results. --- The best cheese in all lots were those cured at 40°F. This may be partly due to the slow rate of curing at the lowest temperatures, in consequence of which the cheese cured at 15° and 33°F. may not have reached their optimum condition when removed from storage. The improvement in texture of cheese cured at low temperatures was even more marked than it was in flavor. In every case there was a closer, firmer texture obtained at low temperatures than at 60°F. The best texture, all things considered, was obtained at 40°F.; the cheese kept at 15° and 33°F. had equally good textures during the early stages of curing, but after about a year they became more or less defective. In every case the cheese cured at 40°F. and below were free from large mechanical holes and no pin or Swiss holes were ever observed, in such cheese. This condition is shown in the accom- panying photographs of cheese made with 3 ounces of rennet and cured at 60° and 40°F. respectively. The color of cheese cured at 15° and 33°F. was uniform and clear for the first year but became somewhat wavy and mottled at a later period. This effect was more marked in the cheese made with the larger amounts of rennet. f In all cheese cured at 40°F. and below small, opaque, whitish specks were produced which were scarcely noticeable when the cheese was cold but became apparent upon warming. The same peculiarity was found in cold storage cheese from various places. These specks are generally inconspicuous and as they have no appar- ent effect upon the flavor have been neglected by buyers as a factor in determining values. The nature of these bodies is unknown. The flavor of all cheese cured below 50°F. was extremely mild and always free from the sharp unpleasant flavors almost invariably found in old cheese ripened at 70°F. and above. To some consumers the mild flavor may be an objection to the process, but the great majority of consumers prefer it to the sharp, biting flavor usually found in market cheese. If desired the flavor may be intensified to almost any degree without danger of the developing of taints, by exposing the cheese to a higher temperature for a short time, after the cheese are sufficiently broken down for consumption. * The commercial value of the cheese cured at 40°F., as fixed by market experts was higher, in each lot, than that cured at any other temperature; even the value of the cheese ripened at freezing and 438 below averaged better than that ripened at 60°F. The cheese cured at 40°F. ranked above the market standard, in all cases. All cheese ripened at 40°F. and below were practically free from mold throughout the whole period, while cheese cured at 50° and 60°F. suffered considerably from this cause. Following the tests above described two more trials of ripening cheese at low temperatures were conducted at the Wisconsin Agri- cultural Experiment Station, in 1901, in one of which a considerable quantity of cheese were made at a commercial factory and placed in curing rooms ranging form 15° to 60°F. within 24 hours from the time they were removed from the press. The results fully confirm those obtained in previous trials. Without exception, the cheese ripened at 40° to 50°F, were superior to those ripened at 60°F. and were in all cases valued above the market standard. They were equal in flavor and superior in texture to cheese from the same lot that were kept two and four weeks at a temperature ranging from 50° to 60°F. before being placed at 40E. In no case was there found in cheese cured at 40°F., any semblance of a sharp, bitter or other- wise unpleasant flavor, while a great advantage was secured in the lengthening of the period during which the cheese was at its best. Most of these cheese were of perfect texture and some of them were given perfect scores, in both flavor and texture, by market experts. Some of them were sent to Chicago and sold to dealers at prices ranging from 2 to 2% cents above the market. Three pairs of cheese, made with 3 ounces, 6 ounces and 9 ounces of rennet respectively, and ripened at 40° and 60°F., were exhibited at the meeting of the Wisconsin Cheese Makers Association, in Feb- ruary, 1901. Before examining the cheese, nearly every old cheese maker at the meeting expressed the opinion that curing temperatures below 60°F, were certain to produce bitter flavors and an imperfect texture, but without exception all pronounced the cheese which had been cured at 40°F, far superior, in both these respects, to those cured at 60°F. There were present at this meeting Professor J. A. Ruddick of Canada and Mr. R. A. Pearson, Assistant Chief of the Dairy Divi- sion of the U. S. Department of Agriculture, both of whom expressed deep interest in the experiments and predicted much good to the cheese industry from the general application of the method. * In the following April (1901), experiments were commenced at the Ontario Agricultural College, on the curing of cheese at low tem- peratures. The result of these tests fully confirm those already de- 439 scribed, the best cheese being those cured at 37° to 38°F. Mr. R. M. Ballantyne, one of the leading cheese dealers of Canada, said regard- ing these cheese that “they (the dealers), universally expressed sur- prise at the condition of the cheese that was put into cold storage at the earliest period, (that is directly from the press), as they expected to find the cheese still curdy and probably with a bitter flavor.” * Bulletin 121, Ont. Agr. College, June 1902. eft In the autumn of 1901 Professor James Robertson, Commis- sioner of Agriculture of Canada, visited the Wisconsin Agricultural College at Madison and after examining cheese cured at various temperatures for six months, selected those cured at 40°F. as the best and said they were ideal cheese for the English market. In the following year, 1902, there were established by the Do- minion Government, by the advice of Professor Robertson, four curing stations in which the temperature was artificially lowered by means of ice. These stations demonstrated the advantage of the method and led later to the establishment, by private parties, of curing stations in which low temperatures were maintained, in most of the cheese sections of Canada. Throughout Canada, the method has been designated as “cool curing” instead of “cold curing” as proposed by Babcock and Russell in their first report upon results obtained at artificially reduced tem- peratures. That this distinction has little significance is shown from the discussion of papers upon the use of low temperatures, read be- fore the Western Ontario Dairymen's Association in January, 1903. At this meeting, Professor Dean, in speaking upon the subject said, “I think they have been splitting hairs in drawing a distinction be- tween cool curing rooms and refrigerators. I believe the distinction is too finely drawn. Where we have cheese cured at 50° or 55° or 60° or 40°F. our experience is that the lower the temperature at which cheese are cured the better the results.” At the same meeting Mr. Ballantyne, in reply to a statement that refrigerator temperatures would not serve for curing, said: “I know it will, because I have tried it. I have carried it on this last year with perfectly satisfactory results at a temperature of about 40°F. Most of the rooms went 38° to 40°F., some of them as high as 45°F. Some of these cheese were taken from the hoops and shipped to me at once. They were immediately put into these cool rooms. The term “cold curing” was proposed by Babcock and Russell to distinguish curing in artificially cooled rooms at all temperatures below 60°F., the optimum temperature that can be secured without refrigeration. Since their experiments, upon which the method is 440 based, included a range of temperatures from 15° to over 80°F., there seems no good reason for designating temperatures between 50° and 60°F. by any other term, as has been done in Canada since 1902. The question in which cheese makers and dealers are primarily interested relate to efficiency and economy rather than to the names by which methods are known. It may be that the improvement in quality and the diminished loss at 40°F. Over higher curing temperatures, are insufficient to compensate for the increased expense involved and the longer period required before the product is marketable. These are questions of vital importance which will be decided in each case by market conditions and by the facilities available. Late in the season of 1902 arrangements were made between the Wisconsin Agricultural Experiment Station and the Dairy Division of the U. S. Department of Agriculture for a cooperative experiment, upon a commercial scale, to test the efficiency of cold curing. The New York Agricultural Experiment Station at Geneva also took part in this test and in order that the cheese used might represent as wide a range of territory as possible two curing stations, one in New York and the other in Wisconsin, were established. The cheese cured at the eastern station were obtained from factories located in Ohio, Pennsylvania and New York; those cured in Wisconsin were made in Michigan, Illinois, Iowa and Wisconsin. The eastern station was in charge of Dr. L. L. Van Slyke and Mr. G. A. Smith, and the western station in charge of Drs. S. M. Babcock and H. L. Russell. Most of the cheese used were typical cheddars suitable for export, but a few of the cheese of the sweet curd type and of the soft cheese made for 10cal consumption in Michigan and Illinois were included, At both stations cheese were cured at 40°, 50° and 60°F. The most serious difficulty in these experiments arose from the wide range of territory from which the cheese were obtained This condition made it impossible to place the cheese in the cold rooms directly from the press, as had been shown by previous experiments to be most favorable to the process, and as the periods of transit varied from 5 to 17 days, during which no temperature control was possible, the cheese were in different stages of ripening when re- ceived and placed in Storage. The cheese were weighed separately and placed in boxes when received and scarcely any attention was given them during the ex- periment. They were weighed at frequent intervals thereafter to determine the relative losses. These losses, however, for the Wis- consin experiments, have little significance on account of the differ- 441 ence in the age of the cheese when received, it being well established that the loss in weight is far more during the first few days than at any subsequent period of equal length. In spite of this disturbing condition, the loss in weight of cheese cured at 40° was less than one-third that at 50° or 60°F. there was little difference in the losses at 50° and 60°F. The cheese stored in New York were received at an earlier age and were in more uniform condition because the periods of transit from the different factories varied but little, the cheese being received about one week from the press in each case. At the end of 20 weeks the average loss per 100 lbs. of cheese stored at 40° was 3.8 lbs., at 50° 4.8 lbs. and at 60° 7.8 lbs. Small cheese (121% lbs.) lost 2.1 lbs. more per 100 lbs. at 40°F. than large cheese (70 lbs.), at 50", the differ- ence was 5.7 lbs. while at 60° it was increased to 7.8 lbs. There is no doubt that the advantage of the 40° temperature would have consid- erably increased, if the cheese had been placed in storage directly from the press. The quality of cheese cured at 40° was superior to that obtained at either 50° or 60° in both the eastern and the western tests; there was also less difference in quality between the cheese cured at 40° and 50° than between those at 50° and 6. It was calculated from results in the New York experiments, taking into account both the dif- ference in quality and the losses in weight, that there was received for 100 lbs. of green cheese put in storage $0.35 more for cheese cured at 40° than for that cured at 50° and $1.08 more than for that cured at 60°F. The cheese cured in New York were subjected to partial chemi- * cal analysis when put into storage and again when 10 and 20 weeks old. These analyses show the percents of water and also the per- cents of the total nitrogen that was soluble in water at these periods. The results are given below. Percentage of water in cheese. Temperatures ..................... 40°F. 50° F. 60°F. When stored 36.50 36.50 36.50 After 10 weeks...................... 36.30 35.70 Q Q’g 9 After 20 weeks...................... 35.25 - 34.66 34.26 Percentage of total nitrogen soluble in water. Temperatures ...................... 40°F. 50°F. 60°F. When stored ----14.55 14.55 14.55 After 10 weeks...................... 20,03 25.18 28.48 After 20 weeks..................... 24.12 31.56 36.24 After 28 weeks...................... 26.27 33.00 -------- After 35 weeks 27.64 sº a m = sº is sº * * * * * * * * * 442 * These results show that neither evaporation nor changes in the condition of the proteids of cheese are suspended at refrigerator tem- peratures, although both take place much more slowly as the tem- perature is reduced. A portion of each lot of cheese, at New York and Wisconsin, was coated with paraffin before being placed in storage, but these cheese were afterwards handled the same as the unparaffined. The shrinkage of the paraffined cheese was in all cases very much less than occured with the untreated cheese while there were no injuri- ous effects noticed. The saving was much more with the cheese kept at 60°F. than at lower temperatures. These experiments fully support the results previously obtained by Babcock and Russell in Wisconsin and by the Department of Agriculture in Canada. Considering all of the recorded trials, the following conclusions are warranted: 1—The ripening changes of cheese take place at all temperatures between 15° and 80°F., the rate decreasing as the temperature is lowered. 2—The growth of organisms which produce gas and taints is practically suspended at a temperature of 40°F. or lower. 3—The best quality of cheddar cheese is obtained by curing at about 40°F. directly from the press. 4—The flavor of cheese cured below 50°F. is mild, clean, and free from bitter or other unpleasant taints. * 5—The texture of cold cured cheese is nearly perfect being close, free from large mechanical or gas holes and with the casein well broken down. 6—The curing losses are greatly reduced, being at 40” less than half that at 60°F. 7—The curing losses may be still further reduced, without im- pairing the quality, by coating the cheese with paraffin before placing them in storage. *. 8–Cheese are more uniform and retain their quality for a longer period, when cured at low temperatures. The cold storage of mature cheese had become quite general before the experiments described above were made public, but the industry at that time was confined wholly to cheese that had been stored at temperatures above 60°F. until they had reached a stage suitable for consumption. Cheese were placed in cold storage for the same reason that meat and other perishable articles were, viz., to prolong the period during which they could be utilized for food. It 443 was universally believed that the cold storage of green cheese was impractical and sure to result disastrously. Following the demonstration before the Wisconsin Cheese Mak- ers Association in 1901, small quantities of green cheese were placed in cold storage by dealers and makers to test the commercial advan- tages of the method, and these trials proving successful, the practice was rapidly extended and as early as 1903 a large proportion of the cheddar cheese made in Wisconsin was handled in this way. Since 1905, practically all of the cheddar cheese made in this state has been put in cold storage, at a temperature of 35° to 40°F. within one week from the press; usually the cheese are shipped from the factory, twice each week, before the ripening has perceptibly advanced. The green . cheese are coated with paraffin before being placed in cold storage; this reduces the loss to a minimum and when the cheese are stored at temperatures as low as 40°F., prevents mold so that the cheese are taken from the curing room in a clean marketable condition without having received much care during the curing process. The expense involved in the instalment of a suitable refrigerat- ing plant precludes the introduction of this process in individual factories. This has been overcome by the establishing of central cur- ing Stations, either through the cooperation of a number of factories or by buyers, to which cheese are shipped for curing as soon as prac- tical after removal from the press. This practice has reduced the cost of factory construction about one-half, since it is no longer neces- sary to provide large, well insulated curing rooms at each factory. Other advantages that have resulted are a better, more uniform qual- ity of cheese that keeps longer, and a very considerable reduction of losses during curing. This system of curing cheese has now been introduced into all cheddar cheese sections of the United States and has proved very satisfactory. The following extract from a letter, dated January, 1910, and written by a cheese dealer in Pennsylvania, expresses the general sentiment regarding the method. “We place our cheese in cold storage four or five days from the hoop ; we have fine results, June cheese coming out like Septembers and hot weather cheese be- ing much improved in quality. We carry all of our cheese at about 36°F. We have no objection to the temperature going as low as 32°F., in fact the rooms frequently drop as low as 32°F. without any ill results.” The most weighty objections that have been urged against the cold curing of cheese are the increased time and expense required 444 and the mild flavor of the product. The first of these is more than, compensated by improved quality and increased yield; the second may be entirely overcome by storing the cheese for a short time, after removal from cold storage, at a temperature of 60° to 65°F. Under these conditions typical cheese flavors increase rapidly while taints rarely develop, the organisms that produce them being either eliminated during the early-stages of curing or held in check by the lactic acid produced. Flavors may also be developed by keeping cheese at 60° to 65°F. for two or three weeks before placing them in the cold rooms, but at this period taints are much more likely to be formed than after the cheese have been ripened in the cold. It must also be borne in mind in this connection, that the majority of consumers prefer the mild, clean flavor of cold cured cheese to the sharp, biting flavors usually found in old cheese cured at high temperatures. Cold curing is not applicable to those types of foreign cheese which derive their peculiar qualities from the growth of specific or- ganisms that do not thrive at low temperatures. Thus Swiss cheese ripened in the cold is of solid texture entirely free from the character- istic holes; Brick and Limburger cheese fail to develop their peculiar flavors, while the fungous growths found in Stilton and Roquefort cheese never appear. There is no doubt, however, that all of these varieties may be placed in cold storage, after the ripening has pro- ceeded to a proper stage, and their good qualities retained for a much longer period than is possible at temperatures above 60°F. 445 The use of cold in cheese-making. By Paul Guérault, Graduate of the Poletechnic School and the Pasteur Institute. Fère Champenoise, France. All fermentation industries are based upon careful observation of the temperature at different stages of the manufacture. The brewery, where the methods of work are now classic, is a characteristic example. The milk, butter and cheese industries should work along the same lines, and make scientific use of the properties of cold. We will examine successively the Services which may be rendered by cold in butter and cheese making, these two industries being almost always combined; and in each case we will endeavour to explain the part it takes first in their manufacture and then in their preservation. Butter making. I. MANUFACTURE. 1. The fermentation of the cream. It it usual at the present time, for all cream to be submitted to fer- mentation before churning, which brings its acidity to 6 or 7 grammes of lactic acid per litre in winter, and to 5 or 6 grammes in summer. This fermentation is obtained by means of selected lactic ferments, and must take place at a constant temperature; 16° C in winter and 14° C in summer. During the warm season it is generally necessary to have recourse to cold. Either the fermentation room, or even the vat containing the cream can be cooled. This last solution seems preferable, especially with cream which has previously been pasteurized. After having passed over an ordinary water cooler, it is easily poured over brine coils, forming a part of the vat itself, which instantly brings the cream to the desired temperature. Now it is well known that pasteurization is much more effective when the cooling, which follows the heating, is effected very quickly. Note that the fermentation rootn should be very easily cleaned, should not contain any germs, parti- cularly mildew, and should not have any smell. i 446 2. Churning. The cream, after staying 48 hours in this room, is churned at 12° or 14" C. It is desirable, then, to keep the apparatus in which this is done at a temperature in the neighbourhood of this. But in all cases it is necessary to have ready, towards the end of the operation, some water cooled to 6" or 8° C. with which to wash the butter; this is the only way to obtain firm butter, having a fine texture and containing a small proportion of water. 3. Despatch. In Summer, it is advisable, before despatching the butter, to place it for several hours, in a place which is cold enough to increase its firmness; it is desirable for the temperature to fall to from 0° to 40 C, which tempe- rature may easily be obtained in the refrigerated cold store. II. PRESERVATION. There is a distinct falling off in summer, in all creamery products. It is, then, very much in the interest of the manufacturer to preserve them so as to put them on the market when prices are good. Before committing himself to this speculation, he must obviously as- certain the net cost of preservation, which may last for 5 or 6 months. It is difficult to give any figures on this subject, it is for each one to calcu- late these for his own plant. In a general way, there is no real advantage to be gained by long preservation, except when the market price fluctuates as much as 20 or 30%. * - - For a preservation of 5 or 6 months a temperature of about 6° C is required. The cold room should have the following qualities: dry air, and darkness, absence of germs and smell. The butter is cooled as soon as it is churned, left 24 hours at 49 or 50 C, and then placed in the cold room. It should be protected there, as much as possible from the action of the air. It is placed in hermetically sealed receptacles of earthenware or wood for instance, being given a preliminary sterilization. Some manufacturers have obtained good results by simply stacking up the cakes of butter ready to be packed and despatched. We should also mention the process which consists in enclosing each cake in ice, which must in this case be made from Sterilized water. In fact it is quite true that water is often the vehicle of numerous germs which are detrimental to preservation. Cold does not possess the property of giving quality to defective pro- ducts. All that can be required of it is that it should give them back just as they were submitted to it. Only perfectly manufactured butter may there- fore be preserved; that made from cream which has been previously pasteu- rized is undoubtedly the best from this point of view. - 447 The condition of the products must be observed during the whole time of preservation. Tasting at regular intervals in the cold store is complicated and insufficient, because, if a defect is discovered, it is often too late for the butter to be despatched. It would seem preferable to take samples of each batch, and place them under normal conditions, outside the cold room. If alteration becomes noticeable within the normal time, preservation is not carried any further. - More certain assurance can be obtained by the following process, which may be said to consist in cultivating the bacteriological growth from the butter. For this purpose the butter to be examined is placed on suitable solid substances. Two or three days later colonies appear in the tubes. When the butter has been well prepared, only lactic ferments are found, which are easily recognised without microscopic examination. If, on the other hand, the oidium or stringy colonies coming from the water are found in great abundance, the preservation is doubtful, and it is advisable to despatch imme- diately on the same day. By observing these precautions great benefits may be derived from pre- servation, from an economical point of view, because it regulates the sale of the butter. In any case, if preservation over long periods involves any risk, an amount of preservation which delays delivery by 15 days or a month is almost indispensable in an industry of any importance. Cheese making. One kind of microbe only takes any part in the manufacture of butter, lactic ferments. The matter is more complicated in the case of cheese. The theories of M. Maze, formed for the most part in our factories, are that there are three groups of ferments combining in the maturing of soft French cheese : 1. Lactic ferments. 2. mould, Oidium, yeast or mycoderms. 3. The fer- ments of cheese which are commonly called red. Their action is sometimes simultaneous, and sometimes successive. It is the temperature which comes in all the time to regulate their proper action. 1. Manufacture. 1. Preparation of leaven by pressure and draining. The manufacturing rooms should, during these operations, be at a temperature of 20 degrees C in winter and 18 degrees C in summer. These places might, perhaps, be arranged so as to be at this temperature naturally, even during the warm weather, or to more or less approximate to them. But a refrigerating in- stallation would give much better results, by allowing the work to be carried out at a constant temperature, and by ensuring success in the draining. which is a delicate operation, the results of which affect the entire manu- facture. - 44S 2. Salting. For salting, cold becomes almost indispensable. It is usual, in most creameries, to do the salting either in the actual draining room, or in a special room at about 10° C. This practice seems to require modification, at least that is the result of the following experiments. The cheeses having a greasy appearance after some time, a certain number of them were salted in a room kept at 10° C. They stayed there 48 hours, after which they went through the ordinary cycle of processes. The result was surprising, the cheeses not only ceased to become greasy, but they became covered with a very fine white mould, giving them the best appearance for sale. The same thing was noticed in certain Italian cheeses by M. Bazzi, Engineer of Milan, in his report to the First International Congress. He re- commended salting by immersion in cold brine as giving entire satisfaction. Salting with brine has been recommended in France by several autho- rites, but up to the present the attempts which have been made have not been encouraging. We have tried the same process, using brine between –2° and 0° C. The results have been more favourable than with powdered Salt in a cold room. In the first case salting must be postponed until the cheese is entirely drained, and the time is difficult to estimate. With cold brine the margin is wider, and the cheese keeps its firmness throughout the maturing period. This points to the fact that probably the action of such intense cold contracts the cheese paste, thus forcing out the whey which must be removed. As for the action of cold on the deposit of mould, it may easily be explained. When cheese is salted at a high temperature, the salt dissolves quickly and flows off with the whey, if drainage has been in the least in- sufficient. This results in the surface not being protected sufficiently against outside contamination. By salting at low temperature, the layer of salt be- comes powdered, or the brine itself protects the cheese; and, as mould is perhaps, of all action the least effected by cold, it is under good conditions for regaining its activity, when the cheese comes back to its ordinary tem- perature. Cold is then, of great service in this stage of the manufacture. 3. Drying and Deposit of Mould. The dried and salted cheese is carried into dry rooms where it gradu- ally becomes covered with a thin mould of a white or slightly bluish colour. The temperature which is most suitable during this period and until the refining period, is about 12" C. When draining and salting have been well done the mouldiness takes place normally; if on the other hand, any mistake has been made, the cheese turns bad, greasiness often sets in, and the surface becomes moist and gives forth a characteristic smell. Cold allows of minimizing these defects to a certain extent. By lowering the temperature to 6' or 8" C, the surface, instead of becoming greasy in appe- 449 arance, becomes slightly rough, and does not any longer have a tendency to run, especially if the cheese is submitted to brisk ventilation. During this period, which lasts for about 8 days, the cheese loses a certain quantity of water each day by evaporation. The result of this is considerable; the daily loss amounts to about 6 grammes for a cheese weigh- ing 450 grammes at the beginning. In summer it is impossible to keep the temperature at 12° C without making use of cold. The plant should be so arranged as to assure suitable evaporation; for this purpose a suitably regulated circulation of cold dry air should be made use of. As for the additional cold provided in certain circumstances, it is obtained by an arrangement of brine pipes, or by direct expansion. In any case good care must be taken only to submit well dried chee- ses to refining, if moist and disagreeable cheese is to be avoided. 4. Refining. When the cheese has become mouldy, and sufficiently dry, it is placed in a cellar, or any other place fulfilling the same purpose ; the temperature there should also remain at about 12" C, but it may fall without in con- venience to 10° or 8% C, and the quality of the product will only be en- hanced thereby. Moreover it is to these low temperatures that certain brands of camemberts owe their quality. It is always difficult to obtain a suitable insulation for the walls of a cellar; it would therefore be preferable to use as a cellar a cold room above ground, which would give the same advantages for preservation in winter as in Summer. Preservation of Cheeses. If by preservation is meant the possibility of stopping all fermentation during a long period (5 or 6 months), and obtaining a product out of the refrigerator identical with that put in, it is certain that the problem is far from being solved, as far as soft cheeses are concerned. - The first condition would mean that cold would have the same in- fluence on all three groups of ferments, whose action in maturing, we have referred to. - f w But this is not the case ; five kinds of lactic ferments, one kind of lactic oidium, spenicilium, four »reds ferments, were set up in suitable sub- stances; the five lactic ferments and the four »red & ferments in two tubes of milk previously sterilized. All were placed in a cold room whose tem- perature was regularly observed. - 1st day 3° C 5th day 49 C 2nd 30 C - 6th , 40 C 3rd , 30 C 7th 4° C • 4th - 4 c 8th day 6° C º' w 29 450 9th x 60 C 12th day 40 C 10th s 100 C 13th x 40 C 11th x 60 C 14th x 40 C On the seventh day mould existed in several colonies. It was the same with the * redº ferments, whose colour was deeply modified and much. paler. As for the lactic ferments, not the least trace of any cultures was observed. The milk was not changed at all. On the 13th day the mouldiness was much increased, as well as one of the red, ferments. The other tubes contained only a few colonies. The milk was curdled by the lactic ferments, but was not affected at all by the caseine ferments. As a stoppage of the engine occurred during this period, and the tem- perature rose until this was set going again, the experiments were repeated over a longer period at an average temperature of 0°C, the extremes varying between – 2° C and +2° C. There was added to the ferments being studied a yeast of the torula variety, of a wine colour, which is fairly often met with in cheese. After 15 days, 3 casein ferments shewed some traces of culture, the torula increased a little but was paler in colour; the rest were unaltered. After 27 days the mould began to increase; two of the red ferments developed slightly, the torula was also increased; in the other tubes no change had taken place. On the 36" day the mould and torula were present in a comparati- vely abundant culture, the red ferments had made little progress, all the rest remained unaltered. At this time the ice machine was stopped. When the temperature rose to 30 C the oidium developed rapidly. The outcome of these experiments is, that, of the 3 groups of ferments it is only possible, by keeping them at a temperature, about 0° C to arrest the lactic ferment, the oidium, and some of the casein ferments. Some of the * red & ferments continue to develop slowly; a parasite such as the to- rula flourishes; lastly, and most important, the mould is only hindered, and altogether only little affected. The same thing is observed in cheese itself. At 4° C in a refrigerator. it becomes covered in 25 or 30 days with a layer of mould thicker than usual. This is explained by the results mentioned above. In fact, in ordinary maturing, the mould exists together with other varieties such as oidium or mycoderms,which use the lactic acid just as the former does. This is not the case in a cold room; the mould alone flourishes and undergoes exagge rated development. As it has the property of digesting the casein, it forms under this thick skin a layer of liquid, and, when the cheese comes back to the ordinary temperature, this quickly commences to run. 451 .* tº its manufacture, and when it has not been dried sufficiently, the quantity of water remaining in the cheese is excessive. We have seen that in a normal case the weight of water evaporated . It is true that when cheese has been put in cold room 3 days after daily, for each cheese, is 6 grammes or 1.33 per cent, and that the time necessary to get a good cheese is 8 days, at a temperature of about 12°C. The proportion of water varies from 60'ſ, or 65% to 45°), or 53%. Now, that which we placed in a cold room at 4° C only lost 3 grammes during the first 3 days, and 1.5 for the rest of the time; as 25 days would be re- quired to bring it to the same point, the total loss would be 39 grammes instead of 48, the proportion of water would thus remain at 51 to 56°lo. However, our refrigerating plant is provided: 1. with a set of direct expansion coils; 2. a circulation of cold dry air, obtained by passing over flowing brine. “A. - As the working time is 12 to 16 hours out of 24 hours, a certain amount of water is evaporated per day. But the circulation of the air does not have much effect, because the difference between the weight of water contained in air at 4° C and that of air at —10° C is not sufficient. An extremely brisk circulation is necessary to obtain good results. It is preferable, therefore, to place the cheese at first in a room kept at 80 to 10°C, this temperature being obtained by a circulation of air through a suitably designed cooler. As for the exaggerated development of mould, it is very difficult to avoid. It must be possible to descend below 0°C, but the proportion of water contained in the cheese (50% at least) would not allow of freezing the paste; which would disintegrate and fall to pieces on leaving the refri- gerator. M. Ruddik, in Ice and Refrigerations, suggested the use of paraffin to minimize this inconvenience. But he referred to hard cheeses, on which mould is of a parasitic nature. Moreover this application was for an almost Smooth dry surface, and the size of the cheeses was large enough not to require much hand labour. It would not be the same with soft French cheeses (bise, camemberts and coulommiers). The cheese would be spoilt by touching it with paraffin, and much hand labour would be required. - It might perhaps, be possible to obtain certain varieties of oidium and mycoderms accustomed to cold, which would develop at the same time as the mould. In the meanwhile the only process consists in turning cheeses over frequently so as to break up the mould, but this also involves an increased amount of work. * Almost completely refined cheese whose surface is already ammoniated may also be preserved. But it is more difficult to sell. Besides attention must be given to the atmosphere, because the ammonia may act on the 29% 452 casein and give it a sharp taste; it is necessary, therefore, to know the pro- portion present in the air at any moment. - The question of preservation has not yet been solved. It would be well to prolong the numerous experiments for this purpose, so as to solve the difficulties met with, one by one. Nevertheless, the possibility of retar- ding maturing for about 1 month, allows the critical period at the begin- ning of summer to be passed through under the best conditions. . A cheese factory of any importance cannot, at the peesent day, dispense with a refri- gerating plant. - -- Each room must be provided with direct expansion or brine coils, as well as steam pipes for warming it in winter. & The application of Refrigeration in the Manu- facture of Roquefort Cheeses at Aveyron. By P. Lebrou, Ingenieur des Arts et Manufactures. The refrigeration industry in Aveyron. The use of artificial refrigeration in Aveyron dates back almost to the construction of the first practical industrial refrigerating machines in 1886. Nevertheless it is not in general use there ; except at the Touren Brewery at Milliau which has had, since 1890 and 1894 two machines of a capacity of 10000 frigories each, it is at present made use of at Roquefort only for the preservation of the cheese of that name, celebrated for 20 cen- turies, and was proclaimed by Pliny who mentions in his Natural History as the 2 Cheese most esteemed at Rome 6. The study of the conditions of the refrigerating industry in this de- partment (Aveyron) will be confined, then, to those at Roquefort. Artificial refrigeration as applied to cheese, may be utilised either to cool the raw material (milk) for transportion, to control its maturing, or, to preserve it. - It is only for preservation that it is used at Roquefort because the milk is treated at the places of production, and because nature alone, in the ripening chambers supplies all the conditions of coolness and humidity necessary for obtaining good cheeses. However, to get a good idea of the use of cold in the one case dealt with in this report, it would seem as well to briefly describe the preparation of Roquefort cheeses. ^ Manufacture of Roquefort cheese. Roquefort is a soft fatty uncompressed cheese, although certain un- informed writers make it out as a dry compressed cheese, obtained from unskimmed sheep's milk") fermented at a low temperature (up to about *) Sheep's milk from the Roquefort district has the following extreme proportions (maximum and minimum) from analyses carried out since 1902: Total casein . . . . . . . . . . . . 5:0 to 8.0% Fatty matter . . . . . . . . . . . . 6.5 & 11.5% (See foot mote next page.) 454 7° C), in caves at Roquefort, whence it derives its name, this gives it a flavour and bouquet of remarkable piquancy and delicacy. This product possesses some most agreable characteristics, and it has for a long time been sent to every corner of the globe. It is in fact known and eaten everywhere and has been called the "king of cheeses.<, a glorious title which no connoisseur grudges it, in spite of the assertions of several manu- facturers of outwardly similar cheeses of palpably inferior quality. Towards the end of the seventeenth century, 250,000 kilogrammes of Roquefort cheese were produced annually; in 1866 the production reached 3,000,000 kilogrammes and in 1908 9,000,000 kilogrammes were consumed over the whole world, representing, a business of 30,000,000 francs to the village of Requefort which has 900 inhabitants. - These 9,000,000 kilogrammes of cheese are obtained from 38,000.00 litres of milk, provided by 450,000 sheep in seven months each year, from December to July. It is not in the village of Roquefort that this large quantity of cheese is made, but in the surrounding district, within a radius of 70 or 80 kilometres, in 400 cheese factories in the country at the places where the milk is actually produced. The cheese is merely cured and preserved at Roquefort. Each of the cheese factories is provided with milk from a distance of not more than 2 or 3 kilometres, which is brought early every morning by the producers. The milk is measured on arrival, then carefully filtered and warmed to the temperature at which the rennet is to be added, so that it is curdled in an hour and a half. The curds are beaten and sprink- led with spores of Penicillium glaucum, (called "pain moisi [bread mould] by the makers) in cylindrical moulds of tinned iron measuring 95 milli- metres in height and twice this in diameter ; with this size the cheese ob- tained should weigh 2:2 to 24 kilogrammes when matured and ready for eating. * The curd is left in the moulds, where it slowly hardens and exudes the whey which it retains after formations, until it has reached the right con- sistency for repening, this requires 6 to 8 days; it is then turned out of the moulds, and carried to Roquefort in the form of cheese where the first treatment it receives it salting. 3 Lactose . . . . . . . . . . . . . . 4-0 to 5.0% Mineral salts . . . . . . . . . . . . 8 & 1.2% Water . . . . . . . . . . . , 76.0 & 83.0°io and the average proportion : Total casein . . . . . . . . . . . . 7.5% Fatty matter . . . . . . . . . . . . 8-0 to 9.0% Lactose . . . . . . . . . . . . . . 4.5% Mineral salts . . . . . . . . . . . . . 1.0% Preparation of cheeses for entering the Roquefort caves. On their arrival at Roquefort the cheeses are first of all salted. For this purpose they are vigorously rubbed all over with fine salt which ad- heres to the surface, and then cooled naturally in piles of four, placed on plates on the ground, in a room specially designed for this operation, called the salting room, adjoining the ripening caves. They are left there for five or six days under the action of the salt. Salting is finished at the end of this time; the salt has permeated the paste by osmosis, and has displaced the whey it still contained, and when more than enough has been put on, it remains in the form of a sticky covering which is removed by hand with a dry cloth. In large installations this cleaning is effected more rapidly by vertical rotating brushes, between which the cheeses pass at the rate of 20 per minute. The clean dry cheese is perforated in places on plates, by means of a device having 30 to 40 points making this number of openings 3 millimetres in diameter, in the cheese, by means of which the paste is internally ventilated bringing about the development of a blue mould which plays an important part in maturing (and contributing to a great extent to the taste which is peculiar to) Roquefort products. After this series of operations the cheese undergoes ripening in the Roquefort Caves, which are hollows in the solid limestone. Geological formation of the Roquefort Caves. It is an extremely curious and interesting geological phenomenon, to which the formation of these caves is due, and which has brought so much fame to the village of Roquefort. Behind the great Plain of Larzac, stretching east and west, is the mountain of >Combalou & 2000 metres long, with a height of about 800 metres. The height is not very great, but on the north side is a very remarkable conformation. There is on this side an abrupt precipice more than 100 metres high, and bristling with sharp rocks. The formation of this precipice is not very ancient. Resting at one time on the summit of the plateau these rocks have slipped on their beds of clay and, in their fall, have become mixed up in a veritable chaos, having among them subterranean galleries, and grottos, at the bottom of which little pools have been formed, and traversed by air currents of great intensity, whose speed frequently reaches 5 metres per second. - These air currents becoming saturated with moisture in contact with the water in the lakes, cause a rapid evaporation to take place, which is sufficient to keep the grottos at a temperature of about 4° or 59 C. From 456 these grottos comes the air which at the same time cools and keeps moist the storehouses for they are veritable storehouses, being as much as six storeys underground — which are called the Caves of Roquefort. Ripening in the Caves. It is in these cool caves that the cheese, placed on wooden racks, is slowly ripened at a temperature about 1° or 29 C. above that of the galleries. - ** After remaining 8 or 10 days in the caves, spots begin to appear on the surface of the cheese, white velvety tufts, gradually becoming blue, they are produced by the growth of cryptogamia, due to the Penicillium glaucum. This white and blue growth lasts as long as the paste is acid, but since the paste becomes alkaline from the action due to the development of mould, a red colour tends, although with difficulty, to spread over the surface. Upon this, that is to say after being placed in the caves for from 15 to 20 days, the surface of the cheese must undergo revirages or scra- ping with a knife, to remove the mycelium growths which form an impene- trable covering, preventing the outside air from reaching the surface and hindering the development of the red colour. At the first scraping, 1.5 to 2% of the weight of the chese is removed, and the rind is then a beautiful creamy white colour. The cheese is then said to have undergone its ºffirst scrapings. When the cheese becomes alkaline the ripening process enters a new phase, and the rind becomes covered with a glazed layer of a reddish tint. It is now almost entirely the bacteria which are at work, bacteria most of which are peculiar to cheese, and which are called x thyrotrix< by E. Duclaux. After 12 or 15 days the glazed layer covers the whole surface, a fresh treatment of the cheese is then necessary, which consists in scraping it a second time, which removes 1 to 1.5% of its weight. The cheese should also undergo a similar scraping every 12 or 15 days for the same reason that it undergoes the second, as long as it remains in the ripening room that is to say until it is sold. The necessity for refrigeration. After the first scraping the cheese is already eatable for lovers of a very sweet cheese, but it is only after the second or even the third that it is really ripe. However it is the taste of the consumer which should be consulted as to when it is to be delivered to him, each fresh scraping making a new stage in the maturing process, after which the flavour and smell are found to be more accentuated. In consequence, in a refining cave, the maturing always advances while the waste increases. Y, 457 But, if at any period of the maturing process the cheeses are placed in a room which is colder than the refining caves, the fermentations are retarded, and by means of sufficiently intense cold, maturing may be stopped at any stage preferred by customers, while the waste involved by each scraping is avoided. It is for this dual purpose that cold is produced at Roquefort; and refrigeration merely useful, at the inception of its application has now be- come a necessity because of the considerable increase in the production of cheese which has resulted therefrom. –2 Artificial cold at Roquefort. The introduction of refrigeration into Roquefort is due to Etienne Coupiac, a man of great intelligence and foresight, who saw in the produc- tion of refrigeration a certain and convenient means of increasing the sta- bility and importance of the trade of Roquefort. * In 1866, Coupiac, as a first attempt, had a refrigerating machine of a capacity of 8000 frigories installed, which cooled a room having a ground area of 25 square metres to 0° C., in which the cheeses to be preserved were stored on wooden frames as in the caves. In this room the cold was obtained by circulating a noncongealable liquid over metal gratings attached to the walls. This attempt at preservation continued for several consecutive years, gave fairly good results as far as the cheese was concerned. But the manner of cooling the chamber was defective; it required constant attention, the refrigerating liquid never flowed regularly, and the distribution of cold was bad. In 1891 it was decided to preserve on a large scale, entirely changing the method of cooling the cold rooms. A complete plant consisting of ro- tating drums on the Linde system which could produce 30,000 frigories in an noncongealable bath was chosen, for cooling 4 rooms of a total ground area of 600 square metres. A ventilator drew the air from the rooms, to send it back through the refrigerator, where its temperature was lowered by several degrees. This time the results were quite different from those of the first trial installation, the mechanical part worked perfectly, but the cheese undergoing preservation turned out badly. Irregularities due to refrigeration and their prevention. In this new installation, the erection of which was entrusted to me, the refrigeration was effected by cold air circulation for which the rooms were the warm point in the circuit, there was much evaporation, so that the cheeses were dried. The shrinkage as indicated on the scales, was 20% in 3 months. The cheeses also gave off a bad odor and had a very pronounced greasy taste. - 458 The penetration of air into the paste was naturally increased by the evaporation, so that it was in the whole mass, and not merely on the sur- face that the bad taste was observed. Analysis of the worst damaged products confirmed the loss of 20% in weight as shown by the scales, and showed me how to find the cause of the bad taste. There had been intense oxidation, as evidenced by the presence of formic acid (it was this oxidation which had given the greasy taste to the paste); while saponification had advanced very little. On the contrary, in the case of a mature cheese which had remained in the ripening caves, oxidation is inappreciable and formic acid is not found, while Saponification continually proceeds under the influence of microbes. From this study we concluded that, under the action of very cold air, the cheese was dried and the action of the microbes retarded, oxidation had proceeded, and no Saponification, or practically none, had taken place, quite the reserve of what takes place in the ripening cave. It was necessary, therefore, when cooling cheese, to keep it out of contact with the air, so as to avoid evaporation, and the action of Oxigen at a low temperature. g For this purpose each cheese was covered with protecting wrappings, and, after having tried several kinds of wrapping we decided on thin sheets of tin foil, which have the advantages of being at once impenetrable, adhe- ring, and which can be used over and over again, either for another wrap- ping, or in the form of scraps for making fresh tin foil. This form of pro- tection, which is still in use at the present day, allows exquisite cheeses to be taken from the refrigerators after a long period of from 8 to 10 months, and sometimes even more, at a temperature of about 0° C., without their losing any of their qualities at this low temperature. Moreover it may be said, that now, thanks to the good effects of the wrapping, assisted besides by the judicious choice of the cheeses to be preserved, the success of refrigeration at Roquefort is assured. Physical modifications in the texture of cheese submitted to intense cold. The maturing of cheese results from two kinds of fermentation: 1. Fermentations not due to air, or interior fermentations taking place where air is excluded. 2. Fermentations due to air, or exterior fermentations requiring air for their action; these effects, in addition to those of evaporation cause the formation of crust on the surface of the cheese. The first are simply retarded by intense cold when enclosed in tinfoil, while the second are completely stopped for want of air. 459 The result of this is that if the crust has formed on the cheese before it is wrapped in tinfoil this cannot increase, and is indeed destroyed. In fact the crust tends to disappear by being changed, because in spite of the temperature being lowered to about 0° C., the fermentations produced which are not due to air set up reactions accompanied by a rise in the interior temperature. This increase in temperature results in the evaporation of the water and volatile constituents contained in the cheese. On the other hand, the temperature of the air in the room being generally lower than that of the interior of the cheese, while the refrigerating machinery is running, and since the tin foil prevents the products of evaporation from getting out, this wrapping fulfils the part of a condensing medium. So, inside the tin foil is a liquid, which, not being able to escape, softens the crust and tends to give it the same texture and composition as the centre by impregnating it with the constituents which it has lost in the ripening process. Adding to this the complete absence of light, after several months of intense cold, we obtain a cheese which is absolutely white, tender right up to its rind, much more homogeneous than it was when refined, instead of being covered with a hard dull coloured crust which is usually uneatable. Preservation thus tends to render cheese homogeneous, and the other great advantage to be derived from its action is that it yields a product which is perfectly edible from centre to surface. Other advantages of refrigeration. To those advantages which we have just studied, two others not less important should be added. Storing them in a refrigerator allows of the cheeses being put in the caves to ripen at more convenient times and of assuring the best Sanitary conditions, by allowing a larger quantity of air to each one, which is of considerable advantage in regulating fermentation, and in avoiding any hindrance to the ripening processes. This precaution, for protection from fluctuations in hygienic qualities, allows besides what is not the least of the benefits to be derived from cold, namely the regulation of the production to suit the demand, while without cold it is the production which regulates the sale and often the profits. Refrigerating installations at Roquefort. At the present time there are nine of these, all of which make use of anhydrous ammonia as the refrigerating medium; eight have compressors on the Linde system without superheating, the ninth works on the Fixary Superheating system. 460 In these different plants, nothing has been left undone to assure regular working ; moreover they are all provided with two compressors, each capable of furnishing the total number of frigories necessary to completely cool their cold rooms, a simple shifting of the driving belt allows of either compressor being used at will. *- & For the refrigeration of the storage rooms, the only method adopted at least up to the present, is that of a circulation of air cooled by direct contact with noncongealable solutions. These refrigerating cellars, although of large capacity, being placed in- side the ripening caves, whose temperature is never above 8° C., are very easily maintained in the neighbourhood of 0° C., by refrigerating machines of a relatively low capacity; thus with 5 or 6 hours working out of 24 in the warmest season of summer, a plant displacing 20,000 frigories in a brine bath at —'59 C., will cool perfectly 1500 cubic metres of rooms, in- sulated by a simple covering of 0.12 metres of conglomerated cork on an enclosure made of hollow terra cotta bricks, 0.15 metres in thickness con- taining 200,000 cheeses of a total weight of about 500,000 kilogrammes. At present the space of the preserving rooms at Roquefort is suffi- cient for the storage of the whole of the cheese produced in one year; which of itself would protect its trade from a slump in the market. 461 Application of cold in Margarine Manufacture. By Ferdinand Barth, Director of the United Margarine Factories, Vienna. In the manufacture of Margarine products such as margarine butter, margarine lard and the various sorts of cooking fats, cold plays an impor- fant part, and finds many applications in various forms, as pure fresh ice water, as Salt solution, in pieces (block ice). - Cooling occupies the first place in the treatment of great quan- tities of milk and cream in the manufacture of margarine butter. The milk is before treatment cooled to a low temperature on various kinds of appa- ratus such as surface, step, tabular, or worm cylindrical apparatus, and again stored in vessels provided with cooling apparatus or in cooled places. The cold is produced by means of machines through pressure from ammonia, carbonic acid, sulphuric acid, etc. Then when the milk and cream are to be prepared for use they are thoroughly pasteurised, which renders all germ and decomposing matter harmless. The pasteurised milk is at once reduced to a low temperature again, by means of cooling apparatus, to prevent any new growth of harmful stuffs. The milk is then warmed to a certain temperature and soured as required in different periods of time. This in effected by means of pure bred cultures of milk acid bacteria (which develop the good aroma and taste). To give the margarine the necessary aroma and the natural taste of butter large quantities of milk and cream are required. After sufficient souring the milk is cooled again until just before use, that is until it is added to the margarine. A further application of cold, and that in the form of water generally cooled to 2–49 C. (so-called apparatus cooling water), takes place in the churning of the fat mixture in the butter machines. These are double walled ; the water in the outer space, between the walls, serves to cool the fat mass in the inner space which is stirred or churned by means of a mixing apparatus. * Further a large quantity of cold, pure fresh-water is required (up to 2° C) for the cooling of the churned, broth-like mass of fat. The cold water streams in fine rain, with a pressure of about one atmosphere, on to 4.62 the mass of fat flowing from the apparatus, powders it and cools it. The fat is formed into fine crystaline grains, which harden gradually, and out of which the water is pressed by rollers. By kneading the fat takes on a homogeneous, butter-like form. - Of late the fat streaming from the apparatus has been cooled in the following manner: Instead of applying ice-water to the fat a series of consecutive double rollers, side by side and over one another, are employed which are hollow and contain cooled fresh water, or directly circulate cold salt solution, which cools the butter mass. The advantage is that the milk and cream parts are not dissolved, as is usually the case, by the water that flows on to the margarine, and the latter has consequently a finer butter aroma and finer taste; the margarine also requires less rolling because it contains much less water. - As is evident from this, when so large a quantity of water is used, a large cooling plant is necessary for the production of cold fresh water alone. Formerly, and even to-day, in small works the water is cooled by throwing Small pieces of ice into the reservoir and stirring them. This process, however, takes up a lot of time and is very expensive. The finished but not yet formed butter must again be stored in cooled rooms; SO too, the formed butter, as also that already tubbed, is stored in cooled rooms, especially in summer. For only a continuous cool temperature, and the greatest cleanliness in working, protect the butter from early spoiling. In making margarine lard large cooled rooms should again be at dis- posal. The fluid fat, still very warm, must be stored there in order to crystalise, that is, to become fine or coarse grained, as is the case with melted natural butter. In manufacturing cooking fats, so-called smooth and tough fats, a large quantity of cooled water is again necessary in stirring, in order to cool the fat and to make it pliant. Finally the manufacture of block ice must be mentioned. This is used for cooling the ice-safes in the shops selling margarine products, and in laboratories for cooling the pure cultures of original milk acids. The latter serve for souring the quantities of milk which come into daily use. The cooling of the rooms is effected by means of tube network, in which common salt solution circulates. The cooling of the milk and cream cooler can be effected directly with ammonia, carbonic acid, sulphurous acid or salt solutions instead of the cooled fresh water; but the last men- tioned is the most preferable. As is evident from this the use of cold in the productions of magarine products is fairly considerable and one must aim at cheapening as far as possible the cost of production of the cold in the rooms, and of the cold water by suitable, tried and practical cold plants. 463 The importance of cooling machines for the purposes of this industry becomes apparent from the fact that a normal manufacture of 1°/2 to 2 waggons requires 200,000 calorics cold machine power; so that the pro- duction in Austria, which amounts to about 1500 waggons annually, requires a cold production of 1,500,000 calorics as a minimum. º Most factories, however, have not sufficient cooling machines and make use of block-ice and artificial ice. This is not only without advantage, but it is also expensive. The cold treatment of milk in the dairy is quite similar to that in the manufacture of margarine. 464 THE PRECOOLING OF FRUIT IN THE UNITED STATES. By S. J. DENNIS, Expert in Refrigeration United States Department of Agriculture Bureau of Plant Industry. ~mºm-º-º-º-º-º-º-º-º: Introduction. During the past ten or fifteen years, the industry of fruit grow- ing on a large scale in the United States has increased rapidly in importance. In the Western and Pacific coast sections irrigation is being extended and large areas of excellent land adapted to the pro- duction of fruits of all kinds are being rapidly brought under culti- vation. As these new plantings come into bearing the production will be greatly increased. On account of favorable climatic condi- tions a very large proportion of the fruit produced in the United States is grown in the Western and Southern portions of the coun- try. As the main market for these fruit crops is found in the large cities of the more densely populated Northeast section, this highly perishable class of produce has to be transported great distances, necessitating the development of an efficient and ample fruit refrige- rator car service. While the present system is admitted to be the largest and best of its kind in the world, there is still a distinct pos- sibility of serious loss by decay or deterioration in transit to the market. With the growth of the industry, this loss has become a problem of increasing importance, sometimes constituting a serious menace to the future of some branches of the industry. Recognizing the seriousness of the problems involved, and their bearing on the future development of an important food-producing business, the Bureau of Plant Industry of the United States Depart- ment of Agriculture has for several years past carried on a series of investigations of the handling of fruits in transportation and storage, with a view to developing methods which would enable such products to be delivered with less loss, in better condition, and over greater distances, thereby extending the marketing area. 465 These investigations are still in progress, but the results already obtained have more than justified their undertaking. In some branches of fruit production, methods of handling have been mate- rially modified and new and improved systems have followed which are having an important bearing on the industry. In general, it may be stated that the opportunity for improvement has been found to lie mainly in the methods of gathering and preparing the fruit for shipment rather than in present methods of fransportation and storage. While the latter are not in all respects ideal, they are, under present methods, responsible for much less loss and deterio- ration, than the treatment which the fruit receives before being shipped or stored. One of the most pronounced innovations which has been brought about as a result of these investigations, is the idea that fruits for best preservation and especially for long distance trans- portation should be thoroughly and promptly cooled before ship- ment. To the process of cooling previous to shipment, the term “precooling” has been applied, and is now in general use. The ques- tion of precooling is at present receiving much attention from fruit growers, shippers and transportation companies. A number of plants for the precooling of fruit have been erected, several of which are already in service; other plants are projected. The Object of Precooling. In the study of the problems connected with the successful and profitable handling and transportation of fruits, some general prin- ciples have been developed, which may be accepted as basic. During the maturing of a sound healthy fruit on the tree, cer- tain chemical and physiological changes which constitute the ripen- ing processes and which result in the development of desirable Qual- ity and flavor are constantly taking place within the fruit. After a certain point is reached, the fruit becomes “overripe,” flavor and quality are lost, and deterioration takes place; finally resulting in the destruction of the fruit either by decay, or through destructive physiological changes. When the fruit is removed from the parent plant and held at ordinary temperatures, these life and death pro- cesses continue. Warm temperatures hasten the ripening and breakdown; low temperatures retard them. It naturally follows that the promptness with which the temperature of the fruit can be lowered to the point where ripening will be checked or held nearly stationary, will materially influence the length of time that the fruit can be held in good condition. 30 During the ripening process the fruit is constantly absorbing oxygen from the surrounding air and at the same time giving off carbon dioxide and water vapor. Any attempt to arrest or retard the ripening by depriving the fruit of Oxygen, instead of preserving the fruit, results in smothering it, and in a more rapid deterioration. Besides the breaking-down of the fruit through overripeness, fruits in general are subject to premature decay by the attacks of various fungi. Investigations of the Bureau of Plant Industry have shown that the molds which are the cause of the common forms of decay of fruit in transit have not as a rule the power to penetrate the Sound, unbroken skin of normal healthy fruits. The spores of these molds are very common and are usually present in sufficient quan- tity to cause decay, when the conditions are proper for their develop- ment. As long as the skin of the fruit is maintained in an unbroken and sound condition, the chances for the development of the decay are very slight. Wounds; bruises, scratches or abrasions of any - kind, however, allow the decay to gain entrance, and once inside, the growth proceeds until the entire fruit is destroyed. The germination of the spores is dependent upon proper moist- ure and temperature conditions. Germination does not take place while the fruit is dry or when the temperature is low. After the spores have germinated and the growth of the fungus has begun within the fruit, low temperatures (as low as 32°F.) do not wholly check its development. The prompt lowering of the temperature of fruit may serve either or both of two purposes: (1) The ripening is retarded and the life of the fruit extended; (2) If the temperature is quickly lowered the germination of the mold spores will be largely prevented and the fruit will arrive din the market in much better condition than is the case where it has been allowed to remain at a relatively warm temperature for some time after picking. When there is considerable delay between the time of picking and cooling, especially in the case of quick ripening fruits, the ripen- ing processes may progress so far that the fruit is well advanced toward overripeness before a low temperature is effective: Delay in the cooling of fruit susceptible to decay from mold results in the germination of the spores and the development of the fungus to a degree not effectively checked by the moderately low temperatures such as are obtainable in refrigerator cars by the use of ice alone. 467 The insulated refrigerator cars now in general use in the United States for the transportation of perishable products, are provided with ice bunkers or tanks at the ends of the cars. The two bunkers of the cars commonly used for carrying fruits have a combined capacity of from four to five tons of ice, and together occupy about one-sixth of the entire interior space of the car. The bunkers are filled through trap doors or hatches in the roof, equipped with tight-closing lids. Openings at the top and bottom between the bunkers and the central or load-carrying portion of the car provide for a circulation of air throughout the car. In the shipments of frozen meats, etc., salt is used with the ice to obtain a lower melt- ing point and to maintain lower temperatures in the cars than is possible with ice alone; in the shipment of fruits, ice alone is em- ployed. When these cars are loaded with warm fruit and the ice tanks are filled, the cooling of the fruit is not, in all cases, as rapid as is desirable. * Methods of packing which are employed, such as the wrapping of individual fruits in soft paper wrappers and then packing tightly into boxes or crates in which the loose portions of the paper wrap- pers almost completely fill the spaces between the fruits, while they are satisfactory and probable necessary for mechanical protection, especially for shipment over long distances, do not admit of a rapid cooling of the fruit. The air circulation which is set up in the cars by the settling of the colder and consequently heavier air through the ice in the tanks, is quite slow, on account of the relatively small vertical and comparatively great horizontal distance which the air must travel in circulating through the greater part of the load. - The present equipment of ice tanks in these cars appears, how- ever, to be entirely sufficient to keep a carload of fruit in good con- dition, after the fruit is thoroughly cooled. To increase the refrige- rating capacity of the cars in the degree necessary to provide for reasonably rapid cooling of warm fruit, would very materially in- crease the cost of equipment and operation. Since there is need for increased refrigerating capacity for a comparatively short inter- val a more reasonable plan is to bring the fruit to a cool temperature before loading in the car, or by mechanical means, promptly after loading. ** Review of Precooling Investigations. In 1904 Mr. G. Harold Powell, of the Bureau of Plant Industry, made a study of the losses from decay in the shipment of peaches 30% from the Southeastern States to the northern markets, and in con- nection with this work nine carloads of peaches were cooled in a refrigerator car which was held at the shipping point and used as a temporary cooling room. A low temperature was maintained in this car by the use of ice and salt in the tanks. After thoroughly cooling, the peaches were transferred to iced refrigerator cars and shipped to New York, where the fruit was very carefully inspected On arrival and compared with other fruit shipped at the same time without having been previously cooled, These experiments showed that the peaches could be allowed to become well ripened on the tree, and develop good flavor and color, and, if cooled promptly after picking and packing, could be delivered in sound condition in the Northern market. Peaches so handled were distinctly superior in appearance and flavor to those which had been shipped in iced cars without precooling and which to compensate for the ripening which necessarily took place before the fruit became well cooled, had been picked in a less mature state. The brown or soft rot, which causes most all of the losses in the shipment of peaches, was greatly reduced in the precooled shipments. Bruising of the fruit by roughness in handling was also found to contribute to loss by decay, the loss being considerably less in the precooled shipments, and least in small experimental lots which had been handled with imore than the usual degree of care in picking and packing. So far as is known, this was the first systematic work on the precooling of fruit for shipment. It followed and was a logical sequence to the investigations of Mr. Powell in the behavior of fruit, mainly apples, in cold storage. These investigations demonstrated that by far the greater part of the losses by premature decay in ap- ples in cold storage, could be traced either to roughness in handling the fruit, or to delay in cooling the fruit after picking. In the spring of the following year, 1905, the first precooling of oranges was done under the direction of Mr. Powell by the De- partment of Agriculture at Los Angeles, California. Ten cars were cooled by blowing cold air from a cold storage plant through refrige- rator cars in which the fruit had been loaded for shipment. This was intended to determine to what extent the slow cooling of or- anges was responsible for the losses from decay in transit. The climate in Southern California during most of the Orange shipping season in spring and summer is very warm, and the fruit when loaded, is usually at a temperature of from 70 to 90 degrees Fahren- heit. Observations of temperatures of oranges in transit, loaded in 469 a warm condition in iced refrigerator cars, showed that about five days elapsed before the fruit was effectively cooled. In the interval while the fruit was warm, decay had a chance to start, and once started, continued to develop even after the fruit had become cooled to as low a temperature as the ice in the cars would maintain. The slow cooling is due in part to the thick skin of the Orange, and in part to the close, tight packing in wooden boxes, the paper wrappers around the individual oranges filling the spaces between them and leaving practically no opportunity for air circulation through the boxes. - \ - - * i s isS i § s | i | i t ! s ; •ozºr Les | & Leg | ze Laz 2e l =2 | Go || J/ tº 2 | 3 || 4 | PLATE 1. Typical temperature record of a car of California, oranges in transit to New York, showing the slow cooling of the fruit loaded in a warm condition in iced refrigerator cars. During the three or four days elapsing be- fore the fruit becomes well cooled, decay has an opportunity to develop in fruit Which has received any wound or injury to the skin. In these experiments, the refrigerated air was conducted into the car through a 12-inch pipe connected to the hatch in the roof of the car over the ice tank at one end. From the other end of the car a similar pipe conducted the air from the car back to the cold storage plant to be again cooled and re-circulated. By suitable valves the air could be forced through the car in either direction. - These experiments demonstrated that oranges thoroughly cooled before shipment can be maintained at a very even tempera- ture in iced refrigerator cars during the period of shipment from California to Eastern markets. 470 During the orange shipping seasons of the following years, 1906 and 1907, about 30 cars of oranges were precooled by the Bureau of Plant Industry, in connection with a comprehensive series of handling and shipping experiments in which both precooled and non-precooled oranges which had been handled in various ways were shipped, some in iced refrigerator cars, some without ice with § N s: : ś , § S R § 75%-25A277&/PAT * - A2/7 * - Aſºº’// Azºrº /907 || 2 || 23 26 Laz Laº Lao Leo || 3 || 7 || 2 || 3 || 4 | PLATE 2. Typical temperature record of a car of precooled California. oranges in transit to New York, showing the nearly constant temperature of the fruit when shipped in a Cold condition in iced refrigerator cars, notwith- standing considerable fluctuations in the outside air temperature. The fruit being constantly at a low temperature, decay does not have opportunity to develop in transit. the roof ventilators both open and closed. This precooling was accomplished by placing the packed boxes in cold storage rooms provided with a liberal amount of cooling pipes. Small fans were placed in some of the rooms to give a more rapid air circulation, but in most cases the boxes were simply stacked in open order and no forced air circulation was used. This investigation, which is the most comprehensive ever conducted in the handling of a single per- ishable product, is too extensive to be fully described here. A de- scription will be found in Bulletin No. 123 of the Bureau of Plant Industry, issued in March, 1908, entitled “The Decay of Oranges While in Transit from California.” As a part of these experiments, to obtain data bearing on the practicability of precooling in the cars, in the spring of 1907 a car precooling plant was again equipped at the plant of the Los Angeles Ice and Cold Storage Company. Insulated air ducts, thirty inches square, conducted the cold air from a coil room containing about 9,000 feet of ammonia piping, to a point alongside the railroad tracks. From these ducts, connection to the trap doors on the roof of the car was made by movable insulated pipes 24 inches in diam- PLATE 3. The experimental precooling plant of the United States Depart- ment of Agriculture, arranged in connection with a commercial cold storage plant at Los Angeles, California, in 1907. eter. Large fans, capable of forcing through the cars any desired volume of air, up to 6,000 cubic feet per minute, were located in both the outgoing and return air ducts. Provision was made for forcing the air in either direction and for the accurate measurement of air velocities and temperatures. During the cooling process, air and fruit temperatures were observed at both top and bottom, at both ends, and in the center of the cars. Temperatures of the fruit, both in the centers of the tightly packed boxes and in the outer layers, were observed by means of specially constructed thermom- eters. Air pressures in the ducts near the cars and in the cars them- selves, were taken by suitable gauges. 2 With this experimental plant, 16 cars were precooled and after- ward iced and forwarded in the usual manner. The refrigerating capacity expected from the amount of cooling pipe in the coil room was not realized, on account of the exigencies of commercial opera- tion of the cold storage plant at the same time that the experiments were in progress. The refrigeration obtained was estimated as be- ing equal to from 8 to 9 tons of ice per day. The cooling of the fruit was quite slow, from 18 to 24 hours being required to bring the average temperature down to that which the ice in the cars would afterward maintain. The time required varied, according to the initial temperature of the fruit, and the temperature and the volume of air blown through the car. The colder the air and the greater the volume forced through the car, the more rapidly the fruit was cooled. It was found that the fruit could be exposed for several hours to a heavy blast of air many degrees colder than the freezing temperature of Oranges, without freezing them or causing any ap- parent damage. Even with the air as cold as 20 degrees Fahrenheit, forced through the car at the rate of over 6,000 cubic feet per min- ute, no fruit was frozen ; the average rate of cooling was only about 2 degrees per hour, in bringing the temperature of the fruit from about 70° to about 40°F. Precaution was taken to reverse the air current through the car whenever the fruit which received the most direct effect of the cold blast became chilled nearly to the freezing point. Fruit in the centers of the tightly packed boxes was very slow in cooling, being usually at least 10 or 15 degrees warmer than the fruit in the Outer and more exposed layers in the same boxes and only a few inches away. Blowing the cold air into the car from either end in alternation had the effect of cooling the fruit at the ends of the car more than that at the center, and after nearly 24 hours of such cooling the oranges in the centers of the boxes in the middle of the car, were usually at temperatures above 50°F., while the fruit at the ends most directly exposed was below 30°F. These experiments showed the difficulty of cooling, fruit wrapped in paper and packed tightly in boxes loaded in cars with little space between the boxes for air circulation. It was evident that to cool oranges effectively when packed in this way it would be necessary to use a very large volume of air at as low a temperature as possible with- out actually freezing the fruit. It was further shown that the very cold air could be blown through the cars for hours without injury, but owing to the unequal cooling in different parts of the car, some of the fruit must be chilled as closely as possible to the freezing point in order to cool the contents of the car as a whole to an effec- tive temperature. - In 1908, in order to overcome the difficulty and expense of ob- taining the facilities necessary for carrying on systematic investi- gations in precooling, a portable experimental plant was added to the equipment of the U. S. Department of Agriculture. This plant can be moved from place to place and used at any point having railroad facilities. An ammonia compression plant of twelve tons daily refrigerating capacity was installed in one end of a specially constructed railway freight car. The other end of the car was T - - - PLATE 4. The portable experimental refrigerating plant of the United States Department of Agriculture, arranged for precooling a loaded fruit car standing alongside. The large air pipes for circulating cold air ºn rough the fruit car, are shown disconnected and drawn back. heavily insulated to form a coil room, in which was installed about 5,000 feet of 114-inch direct expansion piping. Over this piping a current of air is circulated by means of a 45-inch exhaust fan of the centrifugal type. Through openings in the roof of the car the air current may be conducted through removable insulated air pipes, 20 inches in diameter, to either an adjacent building or to a refrige- rator car, as desired. In the spring of 1909 this plant was used in California in ob- taining further data in the precooling of oranges in cars. These experiments corroborated the results previously obtained and em- 474 phasized the necessity for large volumes of low-temperature air for car precooling. This work also showed that considerable refrige- ration may be lost, unless the refrigerator cars are protected from the heat of the sun while precooling. The portable character of the plant, necessitating the dividing of the air pipes into short sections, with the resulting numerous joints between the sections, gave op- portunity to demonstrate that a material loss of refrigeration may easily occur through apparently insignificant air leaks. The difficulty inherent in the rapid cooling of fruit covered with a thick protective skin like that of an orange, was clearly brought PLATE 5. The portable experimental refrigerating plant of the United States Department of Agriculture, arranged for precooling a loaded fruit car on same track, showing the large pipes through which cold air is circulated. out in experiments in which unwrapped oranges were exposed to air currents at temperatures as low as 16°F. for from one and one- half to two hours, before actual freezing began, although ice forms in oranges when inserted thermometers show temperatures from 27° to 28°F. The portable experimental plant was also utilized in the fall of 1909 in experiments in precooling California table grapes in cars. These experiments, however, were not sufficiently comprehensive to form a basis for satisfactory conclusions. It may be said, how- ever, that the precooling was effective in reducing the losses in transit from decay following injuries to the fruit due to careless handling, but it was apparently less effective in reducing (and in some cases failed to prevent) the development of other forms of decay which are in evidence in wet weather. Small Fruit Cooling Plants. For several years a number of small fruit cooling plants have been in use on fruit farms in the United States. Most of these plants are located on small farms in the valley of the Hudson River in eastern New York. In this section the climate is such that natu- ral ice can usually be harvested and stored at very low cost, so that with few exceptions, these plants are cooled by the use of ice. The buildings in practically all of these plants are of inexpen- sive wood frame construction, insulated by filling the walls and floors with sawdust or mill shavings. They consist of one or more small insulated rooms, cooled in some cases by a gravity circulation of air from an overhead ice chamber, but most often by upright sheet metal cylinders eight to twelve inches in diameter ranged along the walls and filled with crushed ice and salt from the floor above. Suitable troughs at the bottom serve to carry away both the meltage from the ice and the moisture condensed on the outer sur- faces of the tubes. A few plants are cooled by the gravity brine system. In these plants the rooms are cooled by brine coils, the brine being cooled in coils submerged in an ice and salt mixture in an overhead insulated tank. The piping is so arranged that the cold brine is circulated by gravity from which the system takes its name. A few plants of larger size, cooled by mechanical refrigera- tion, are also in use on fruit farms. These small plants are utilized mainly for storage purposes, to enable the growers to harvest their fruit crops at the most suit- able time and to hold them until market conditions are favorable. The plants being located at the Orchards, enable the fruit to be very promptly cooled after picking, and packed and shipped while still cold. Under conditions so favorable to the preservation of the quality of the fruit and the prevention of decay, fruit may be safely held for a considerable time. Very satisfactory results have been obtained in most of these plants, although the construction of some of them is not of a very permanent character. The precooling feature is largely incidental, precooling being less necessary, on account of the proximity to large markets, than is the case with the large fruit growing districts of the West and 476 South. These plants, particularly those cooled with ice and salt, serve very well for precooling on a small scale. The comparatively low melting temperatures attainable with the ice and salt mixture enable the cooling to be accomplished in small rooms at a reason- ably rapid rate, even without the aid of a forced circulation of air. With a forced circulation, there appears to be no reason why such plants could not be successfully operated on a larger scale, where the cost of ice is such as to make this method of refrigeration eco- nomical. Development of Commercial Precooling. Following the investigations of the Department of Agriculture, the interest of fruit growers, shippers and transportation companies was aroused, particularly in California, and directed upon precool- ing as a possible means of reducing losses in transit. Seven com- mercial plants have been erected. Three of these are large plants of the car precooling type, and the other four are smaller plants for cooling before loading in cars. The car cooling plants were erected by the railway companies, two by the Southern Pacific Company, the other by the Santa Fe system. The Car Precooling Plants of the Southern Pacific Company. The two plants erected by the Pacific Fruit Express Company, a subsidiary corporation of the Southern Pacific Company, are lo- cated at Colton and Roseville, California. Both places are gateway points where several local lines converge to the main trunk line to the East, and where large numbers of cars of fruit are concentrated. The two plants are along similar lines as regards the precooling features. Both are operated in connection with large newly erected ice manufacturing and car icing plants, the same machinery being used for either the precooling or ice making, as required by cir- CunnStan CeS. . The Colton plant is designed to cool twenty cars at one time, From a main cold air supply duct, extending alongside the track, flexible branch pipes connect to insulated false doors, which are set into the doorways of the cars. The main return or suction duct is located high up over the track, and from this depend flexible pipes which make connections to the ice traps or hatches at both ends of the cars. The cold air blast is thus introduced at the middle of the car through one of the side doors, and, dividing, flows in either direction to the ends of the car, passing out through the trap over the ice bunkers. The plant is designed to deliver 10,000 cubic feet of air per minute through each car. This volume being divided into 477 two currents in the car, gives an air movement in the car of 5,000 cubic feet per minute from the center to each end. The introduction of the air in the center is designed to insure thorough cooling of the portion of the load farthest from the ice bunkers. The air is circulated intermittently, according to what is known as the “Intermittent Vacuum System.” Under this system, the cold air supply to the car is at intervals cut off for a few seconds while the fans continue to exhaust air from the car, the air exhausted - PLATE 7. The car precooling plant of the Southern Pacific Company at Roseville, Cal. Interior of car shed, showing the door connection for intro- ducing the cold air at the middle of the car. meanwhile being discharged to the atmosphere. After a few sec- onds, the cold air is again admitted to the cars, the exhaust to the atmosphere is closed, and the normal air circulation over the cooling coils and through the cars is re-established. This process is intended to discharge from the cars and air ducts the warm air and the ex- halations from the fruit, on the theory that these exhalations are harmful to the fruit and tend to promote decay if not removed. It is claimed for this system that by the thorough removal of the gase- ous exhalations from the fruit, the fruit in the cars precooled in this way is less liable to develop decay in transit, and that the pressure - - variation in the cars is sufficient to hasten the cooling of the fruit, by an appreciable expansion of the warm air from the packages each time the pressure is reduced by the intermittent exhaust. Immediately after precooling and disconnecting the air pipes from the car, the ice tanks in the cars are filled with ice from an icing platform located over the main cold air supply duct, and upon which the ice is placed in readiness while the precooling is in pro- gress. The precooling and icing are thus both accomplished with one setting of the cars. Under this arrangement, the precooling PLATE 8. The car precooling plant of the Southern Pacific Company at Roseville, California. View of the car shed showing a train ready for precool- ing. Cold air is blown into the cars through pipes connected to the car doors on the other side, and leaves the car through the flexible pipes connected to a *uction duct overhead. process occasions no extra delay for additional switching, the only additional time required being that required for connecting and dis- connecting the air pipes, in addition to the time that the cold air is being actually circulated. An open shed covers the icing platform and the cars on the precooling track, and protects the cars from the heat of the sun during precooling. The Roseville plant is along the same general lines as the Col- 479 ton plant, and is designed to operate on the same system. It has a capacity of twenty cars at one setting. The Precooling Plant of the Atchison, Topeka and Santa Fe Railway Company. This plant was erected by the Santa Fe Refrigerator Despatch (a subsidiary corporation which handles the refrigerator car busi- ness of the railway company), and is located at San Bernardino, in Southern California, where the shipments from local points converge to the main line. Like the plants of the Southern Pacific Company, it forms a part of a recently erected ice manufacturing and car icing plant. It is designed to cool thirty-two cars at one setting, sixteen cars on each of two adjacent tracks. The air ducts, which are of large size, extend between the two tracks, the high pressure or main supply duct lying directly under the low pressure or return duct. The ducts are of concrete construction, insulated on the interior with corkboard. The top of the ducts forms the icing platform, from which the cars are iced after precooling. At one end of the ducts are the fans for circulating the air. One set of fans draw the air from the low pressure ducts and discharge it over the brine piping in the coil room. Another set of fans take the air from the coil room and force it into the the high pressure duct, from which it is conducted into the cars through the laterals or branch pipes. These laterals rise vertically from the center of the ducts, and arch over the tops of the cars with two jointed swinging sections, providing a very flexible connection which may be adjusted to the ice traps of the cars placed at any point along the track. All laterals are provided with valves opening into both high and low pressure ducts; either of these valves may be opened and any lateral connected to either duct as desired. These valves make it possible to reverse the direc- tion of the cold air current through any car at any time without affecting any other car. By the arrangement of fans already described and by suitably regulating the speed of the two sets of fans, the air pressure is main- tained in the supply duct as much above atmospheric pressure as the pressure in the suction duct is below that of the atmosphere. The object of this is to maintain in the cars an average pressure equal to or slightly above the atmospheric pressure, and prevent loss by drawing warm air into the cars. To maintain the pressure in the system and compensate for loss of air by outward leakage an automatic intake valve is provided at the end of the suction duct farthest from the fans, which automatically admits air from outside 480 whenever the vacuum in the suction duct exceeds a predetermined amount. Any warm air entering the system through this valve 1must pass the entire length of the suction duct, which is piped with brine coils, and over the cooling coils in the cell room, and hence will be thoroughly cooled before it can enter the car. Any leakage which may occur will be of cold air outward rather than of warm air into the cars, and the result of any unavoidable air leakage will thus be a loss of refrigeration only, without interfering with the cooling of the fruit. sº To prevent too great difference between the pressures in the supply and return ducts, when less than the full number of cars are connected, an automatic bypass valve, which connects the two ducts at the end farthest from the coil room, opens when the pressure dif- ference exceeds a certain amount, and allows more or less air to cir- culate through the ducts without passing through the cars. All parts of the air circulating system being thus constantly and equably refrigerated, with the exception of the short lateral connecting pipes, any number of cars may be connected at any position along the main ducts; all will receive equal volumes and temperatures of air and hence will be equally refrigerated. The warm air contained in the cars before precooling is not drawn into the system, but is discharged in a simple manner. In connecting the cars to the plant for precooling, the ice traps at both ends of the car are first opened and connection made to one of them from the supply or pressure duct, Cold air is blown into the car through this connection for a few moments, displacing the warm air in the car and forcing it through the open trap at the other end. The in the car and forcing it out through the open trap at the other end. The air which is thus withdrawn from the system is automatically replaced by air drawn in through the intake valve at the end of the the other end of the car is connected to the suction duct and a con- tinuous circulation begun. Any emanations from the warm fruit which may have accumulated in the car are considered to be suffi- ciently disposed of by this method and no further ventilation or change of air in the cars or ducts is regarded as necessary. The cold air is introduced at one end of the car and withdrawn from the other, the direction of air through the car being reversed as found necessary. The plant is designed to force about 8,000 cubic feet of air per minute through each car. * - The brine system of refrigeration is used for cooling both ducts and coil room, in order to provide for a storage of refrigeration dur- ing the periods intervening between trains and to enable the plant 481 to meet the very heavy and sudden demand upon the system which occurs when the air is first circulated through a trainload of warm fruit. Plants for Precooling Before Loading in Cars. Four plants for precooling fruits before loading in cars have been erected in California. In all of these, the cooling is by forced or gravity air circulation in insulated rooms. Three of these plants have been erected by local associations of citrus fruit growers, two being cooled by mechanical refrigeration, and the third by the grav- ity brine system, using ice and salt as a refrigerant. The mechanic- ally refrigerated plants are both operated in connection with ice manufacturing plants. One of these plants, located at Pomona, Cali- fornia, is operated as an adjunct to a local ice and cold storage plant previously established, refrigeration and ice being purchased from the ice and cold storage company, while the other, located at East Highlands, California, is a complete ice making and precooling plant. In these plants, the fruit is placed in the cold rooms immediately after packing, and allowed to remain 24 to 48 hours, or until its tem- perature is reduced to about 33° to 35°. From the cold rooms, the fruit is loaded directly into iced refrigerator cars. Another plant of a somewhat different type has been in opera- tion for over a year at Newcastle, California. In this plant, the packed boxes of fruit are placed on a mechanical conveyor and car- ried through a refrigerated compartment at a speed which may be regulated so as to keep the boxes for any desired period in the compartment. The conveyor, which is the special feature of this system, is arranged to carry the boxes repeatedly back and forth across the chamber, in such a manner as to expose the boxes very thoroughly to the forced air circulation. After passing through the compartment, which is cooled by a mechanical refrigerating plant, the boxes are discharged upon a platform from which they are loaded into refrigerator cars. It is claimed for this system that the exposure of the boxes in all positions to the air blast results in more rapid and uniform cooling than is possible where the boxes remain stationary in a steady current of air. The packed fruit from packing houses nearby is brought to this plant for cooling and loading, the plant being operated by an independent company and not in connec- tion with any packing house. *- Like all citrus fruits, the orange ripens very slowly, and when handled with care and packed in sound condition, is less in need of prompt cooling, from the standpoint of the control of ordi- 31 482 nary decay in transit, than almost any other commercially important fruit. Notwithstanding this, the results obtained from the precool- & ing plants already erected have been sufficiently favorable to lead many California orange shippers to regard precooling as a distinct step in advance. Following the adjustment of transportation charges to meet the new conditions, a considerable development in the ap- plication of precooling is anticipated in California. It seems certain, in view of the number of plants already erected, the variety in type of these plants, the conditions under which they are managed and Operated, and the volume of shipments which are now being made under precooling, that the practical application of the process is undergoing in California a fairly thorough test, which will go far toward determining the future status of precooling as a factor in the commercial handling of fruits and produce. Special Problems Involved in the Precooling of Fruits and Vegetables. In the commercial application of precooling a number of special problems have arisen, some of them economic, others dealing with more technical considerations. Many of these problems have al- ready received considerable attention, but further developments are to be looked for along nearly all the lines indicated. Whether precooling can be accomplished to best advantage by the shipper before delivering his product to the transportation company, or by the transportation company in cars after shipments are received by them, is a problem still under discussion in the United States. In California the transportation companies offer their newly equipped car precooling plants as the most economical means for the quick cooling of such fruits as they are to carry under refrigeration, while some shippers who have provided themselves with warehouse precooling facilities, claim that the more prompt cooling which they are able to do, is more effective in placing their shipments in condition for safe transportation. Another problem arises from the fact that a precooling plant, which of necessity represents a considerable investment, must un- avoidably remain idle for a considerable portion of each year. The machinery and power equipment of such a plant, which represents by far the greater part of the investment, is identical with that of an ice making plant, and the two elements have been combined in nearly all the plants so far erected. During the season when pre- cooling is needed, these plants are arranged to devote most or all of . their refrigerating capacity to that work, and at other times the 483 same machinery is devoted to the manufacture of ice to be stored and used for icing the cars that are to be precooled later on. Such a plant is well adapted to the needs of the transportation companies, but in the case of combined precooling and ice plants operated by shippers, it introduces an innovation as regards the icing of cars by the shippers instead of by the transportation companies. Freight and refrigeration charges on shipments precooled by the shippers or by the transportation companies, according as they may or may not require re-icing in transit, and the determination of the relative responsibility of shipper and transportation company for proper refrigeration and condition on arrival at destination, of shipments precooled or iced by the shippers, are problems still under- going adjustment. * Warehouse vs. Car Precooling. More technical in their nature are those problems relating to the general type of plant to be erected, i. e., whether of the ware- house type for cooling fruit or produce before placing in cars, or of the car cooling type for cooling after loading for transportation. From a technical standpoint, the warehouse cooling plant located at the shipping point, presents a number of advantages, foremost of which is that of promptness in placing the produce under refrigera- tion. In the warehouse plant, the fruit or produce may ordinarily be made ready for the cooling process with at least no greater delay than would be involved in loading the same produce into cars, while with the car cooling plant, there will, in general, be more or less delay before the loaded car can be hauled to and connected with the precooling plant. The more perishable the fruit the greater the ad- vantage to be derived from prompt cooling and the more serious the effect of delay. The effectiveness of the car cooling plant, will undoubtedly depend in a large measure upon the promptness with which cars loaded at nearby shipping points can be assembled at and connected with the cooling plant. s In the warehouse type of plant, rapidity and uniformity of cool- ing, and economy as to refrigeration required, are almost entirely matters of design, under conditions already familiar to the refriger- ating engineer, such a plant following largely the lines of a cold storage plant. An important difference, however, is in respect to the air circulation, which must be much more rapid and more thoroughly distributed, if the cooling is to be as rapid as is likely to be desired. Aside from this, the only special problems in design are those relating to the provision for rapid and frequent movement 31% 484 of produce in an economical manner, and for the loading of the cooled produce into iced refrigerator cars without allowing it to come into contact with warm moist air at any time. This last ap- pears to be of particular importance in the case of fruits subject to damage by molds, as the condensation of even a slight film of moist- ure upon the cold surfaces of such fruits, provides one of the con- ditions favorable for the development of such growths. -- No departure from established methods, as to style of package or method of loading, is required, although more Open types of pack- age to allow of more rapid cooling may ultimately prove desirable. An economic objection to the precooling plant operated by the shipper, lies in the relatively large investment required, which may be greater than would be practicable for the small shipper in many cases. In California this objection has so far been met by the erec- tion of warehouse precooling plants by associations of shippers. Another proposed solution is the construction of such plants either by independent warehousing companies or by the transportation companies themselves, in cases where it is impracticable for ship- pers to provide their own plants. The car precooling plant presents a number of new problems in design, many of which have already been made the subject of patents. At the outset, certain factors must be considered. The present types of package, method of loading, and interior arrange- ment of refrigerator cars, are not well adapted for rapid and uniform cooling by a cold air blast. This makes it necessary to utilize air at as low a temperature as is feasible, and to force it very rapidly through the cars in order to obtain reasonable rapidity of cooling. To force air in the necessary volumes, requires the use of very large fans and air ducts, and necessitates an appreciable difference in air pressure within the car itself, between the point of air inlet and dis- charge. Refrigerator cars, probably on account of the jolting and racking to which they are subjected in use, are far from being air tight, except when new. Experiments show that an air pressure or vacuum in the car equivalent to from 96 to 4% inch head of water, is sufficient, usually, to cause an air leakage, either inward or out- ward, according as there is vacuum or pressure in the car, of over 1000 cubic feet of air per minute; or the leakage under such pressure is equal, approximately, to at least one-half the cubic contents of the car per minute. Several patents relating to methods of controlling and distributing the air pressure so as to minimize the effect of air leakage have already been issued or applied for in the United States. 485 The temperature of the air forced into the cars may be much lower than the temperature to which it is desired to bring the pro- produce, especially at the beginning of the operation. The more thoroughly the produce is protected by the package and method of packing the colder the air may be employed. To accomplish the pre- cooling as rapidly as is desirable in a car cooling plant, it is neces- sary that the temperature of the air be as low as can be employed without danger of freezing or chilling such of the contents of the cars as receive the most direct effect of the cold blast. The method of introducing and distributing this extremely cold air so as to ob- tain as uniform cooling as possible in all parts of the car, to avoid undue chilling of any portion, is a problem still open for inves- tigation. e - In the case of the car precooling plant, the time required for cooling is a factor of the greatest importance, in order to avoid undue detention of the cars. In the warehouse cooling plant, the time factor is less important. The car cooling plant must be designed to use air at lower temperatures, and hence with more liberal pipe sur- faces and somewhat larger refrigerating machinery than is required for the warehouse cooling plant of equal capacity. The relatively large volumes and low temperatures of air make it necessary to employ large, tightly constructed and well insulated air ducts, in order to avoid undue loss of refrigeration. The branch connections from the main air ducts to the cars and the means for making connection to the car, present a number of minor problems in design, which are, nevertheless, important. These connections nust be of good size to carry the necessary volume of air, must be at least fairly well insulated, and must allow of considerable flexi- bility as regards the position of the car. The point of connection to the door or roof opening of the car is one at which a very appreciable leakage may easily occur, and the loss of refrigeration may be con- siderable. Refrigerator cars are not built to exact standards as to size, height, or length, and the size and relative position of door and roof openings vary considerably. The openings in the roof through which the ice tanks are filled unavoidably become more or less battered and uneven in service. To provide connections to such openings, which may be easily and quickly handled, and which shall be as nearly as possible air-tight, is a problem in design which affords opportunity for the exercise of considerable ingenuity. Sharp bends or irregularities in these connecting pipes cause eddies in the air current, tending to choke the same, and necessitate a greater pres- sure in the main ducts than would otherwise be necessary to circulate 4S6 the required air volume through the cars. The increased air pressure in turn calls for greater power to drive the fans, besides increasing the tendency to leakage in the ducts. Economy of refrigeration re- quires that this leakage be kept at a minimum. The rapid cooling of the packed fruit will necessarily result in more or less unequaled cooling owing to the fact that the closely packed fruit in the interior of the packages cannot cool as rapidly as the outer layers in the same packages. Moreover, the disposition of the load in the car is such that the cold air blast cannot reach uni- formly to all parts of the load, and some packages will cool much more rapidly than others. The more the cooling is forced the more marked is the inequality of temperature. The average temperature of the whole load at which it will equalize, after the cooling process, will necessarily be considerably above the temperature of the fruit most directly exposed to the air blast. This makes it unsafe to at- tempt to bring the average temperature near the freezing point, on account of the danger of freezing the fruit most exposed to the blast. The cooling, which begins at a comparatively rapid rate, becomes much slower as the fruit becomes colder, so that the latter portion of the cooling is accomplished at a relatively slow rate, and hence at greater cost. Considerations of safety and economy indicate that an average temperature for the whole load of from 40 to 45 degrees is probaly as low as is feasible with the car cooling plant. This is, as a matter of fact, as low a temperature as will be maintained by the ice in the tanks of the car, under ordinary weather conditions. More open types of packages and methods of loading calculated to permit a more thorough and uniform distribution of the cold blast to all parts of the load, would admit of considerable improvement as to rapidity and uniformity of cooling in cars, and if this method of cooling comes into general use, changes along these lines will undoubtedly be necessary, and will furnish further problems for consideration. 487 The Preservation of Fruits de Luxe. * —- By H. van Orshover, Agricultural Engineer, Hoeylaert. Experiments have long been made in different parts of the world on the preservation of fruit by cold. Thanks to the perfection of refrigerating machinery, Europe is abundantly provided at any time of the year when its own reserves tun low, with exotic fruit, either preserved from one season to another in stores, or transported by cold storage ships from one hemi- sphere to another. - Thus, to mention the best known cases, Cape Colony and Australia, where from their geographical situation fruits ripen naturally at times when it is very expensive to produce them in Europe at very little cost can successfully place them on our markets. North America has come to pre- serve the fruit from its immense orchards in excellent condition and to send it out at the most opportune time. There is one danger, which the European producer must not lose sight of; benefitted by the ready market offered by the dense population of our part of the world, he does not have to undertake long transportations like the producer in less densely populated districts, who must seek a sale for his products over the seas. Now, that our markets are receiving fruits from over the ocean, which easily compete with our own in the lowness of their price if not in their quality, it is important for the producers thus affected to find means which will enable them to resist the competition; the wisest policy is, when an adversary uses more perfect weapons, to try to imitate them ; let us meet cold with cold ! It is not the intention here to dwell upon the possibility of preserving fruit by cold, nor upon the advantages to be derived from this process; numerous instances in Canada, in the United States, in Cape Colony and Australia, also experiments made in certain European centres, prove beyond doubt that these questions are solved. But besides certain details of ap- plication, there is a knotty problem to solve, this is the realisation of econo- mic production in our country, and, up to the present no one seems to be engaged in solving it. Experiments have been carried out in Europe by scientific men, by groups of producers and by cold storage companies. In the first case the economic side was seldom touched upon, the second often 488 *… consisted in efforts subsidized by governements, in the third case the places intended for other products were used when these were scarce. One of the principal objections made to the use of artificial refrigeration is that it costs too much; the remedy therefore consists in using the installation as constantly as possible. - Now preservation by cold seems specially desirable in our country for delicate fruits, which undergo changes very quickly, and for which there are considerable fluctuations in price. If we follow the market prices for grapes, peaches, strawberries, etc., we always see that the highest prices are ob- tained on the appearance of the first products, this price for the same quality, falls progressively until the maximum production is reached, and increases as the fruit becomes more scarce; it is only at this last period that preservation can be economically carried out. The average prices') of fine Frankenthal grapes during the summer of 1909 in Brussels (which regulates the prices in Central Europe), were as follows: Mid April . . . . 10 – francs per kilogram X May . . . . . 450 X X. * X » June . . . . 2:60 × X X X July * * ~ * * 1-70 X. X X * August . 1'40 x > X 2 September . . 180 X X X » October . . 2:50 x X X. X November . 3– X. X. X Thus the lowest period is just about in the month of August, and it is from this month that cold storage could be used until the month of November or even perhaps until the beginning of December, assuming the longest practical time of preservation to be one month. Let us examine the prices of Gros Colman grapes alongside these figures: Mid July . . . . . 3.- francs per kilogram » August . . . . 270 × X X » September . . . 2.60 × X. X » October . . . . 2:30 x X X. » November . . . 240 x X X - » December . . . 1.80 × X X > January . . . . 280 × X X. » February . . 3'2O > X) X » March . . . . 4:60 X X X. Here the price does not commence to rise until the month of January, . and continues up to March and April; in this case cold storage could be used from the month of December. 1) Prices of the Flower Fruit and Vegetable Growers Co-operative Society (Producers' Market), Brussels. s bºr- 489 It is true that famines sometimes occur in the fruit market, when the prices rise by a considerable amount; and it is profitable to preserve the fruit up to the time of the highest price, but this is always a risky speculation, as fluctuations in price are controlled by influences which are impossible to foresee; it may be said, then, that it is only advisable to store fruits de luxe between the height and the close of the season; the above figures show that this period is relatively short. When, as is the case in large towns, there is a refrigerating installation ready to hand, which is used for alimentary products, certain parts of this •ºmay be made use of; unfortunately fruit is produced in districts unprovided with such cold stores, and it becomes necessary to build them specially for this purpose, so that the cost of establishing them would have to be enti- rely defrayed by the fruits preserved. In some fruit producing districts, it is possible to combine different kinds in cold 'storage. This is notably the case in the district of Hoeylaert (Belgium), which specialises in the production of Frankenthal and Gros Colman Grapes. The prices rise very high, so that much can be expected from an installation in use from August or September until March. Still this is only part of the time, and there yet remain several months during which the capital invested is unproductive. The remedy for this must con- sist in combining the preservation of fruits with that of other products Suited to the conditions of the cold store; it is these products which should be sought for in each particular case. The isolated producer, absorbed with the cares of his own production and trade, cannot undertake any experiments, which necessitate some kind of co-operation, moreover, the usefulness of cold storage often appears to him to be imaginary ; the syndicates themselves do not possess sufficient property or resources to attempt it under favorable conditions, and it is to be hoped that public bodies will assist, either by establishing experi- mental stores, or by subsidizing companies, who would undertake to carry out researches under their direction. Considering the usefulness of cold stores for the preservation of fruits de luxe, * Considering the difficulties which beset the economical application of this process, The motion before the Congress is, that it would be desirable for Governments to lend their assistance in order to get cold storage plants permanently in use in fruit producing districts, and thus to contribute to- wards their general use. …* 490 Appropriate Refrigeration Plants in modern Slaughter Houses. By Mr. Dohmann, Director of the Municipal Abattoirs at Cottbus (Germany). At the I. International Refrigeration Congress at Paris in 1908 a demand was formulated, if I am well informed, to the effect that there should be no slaughter house without a refrigeration plant. The justice of such a demand appears not only from theoretical considerations, but particularly from the fact that most of the existing abattoirs are provided with refrigera- tion plants and that new slaughter-houses are hardly likely to be built with- out refrigeration plants. & a, The importance of preserving meat by means of cold is acknowledged both in the circles of hygienists and of butchers and provision dealers. This is proved by an observation we can make in Germany, that in large and small towns the dealers in meat and provisions, who do a big trade in meat and sausages, have fitted up special cooling rooms on their premises in addition to the refrigerating plants at their disposal in the slaughter houses. Nay, of late, in the small towns which do not yet possess an abattoir, the dealers in meat and provisions are clubbing together to establish a refrigerating plant at their own expense; this for example, is said to be the case at Husum (Germany), a town of about 10,000 inhabitants. But the more generally the importance of preserving meat and other animal provisions by means of cold is appreciated, the more actively must hygienists and technicians be bent upon creating refrigerating plants by cooperation, which guarantee an expedient and perfect preservation of the articles of consumption. - In the modern slaughter house refrigeration plants we almost invariably find one or two so called preliminary cooling chambers and the refrigerating room proper. The preliminary cooling chambers have answered excellently and are now hardly to be dispensed with because they prepare the meat appropriately for the refrigeration room. The refrigeration room, properly speaking, is the more efficacious and expedient the more continuously a temperature of between 0 and + 4° C can be maintained in it and the more the proportion of moisture of the air circulating in it is in accordance 491 with the requirements that must be satisficq in the interest of a hygienically unobjectionable and economically advantageous preservation of the meat. A temperature as constant as possible — assuming an irreproachable func- tionating and a judicious working of the apparatuses in the refrigeration room — can only be attained if the refrigeration room, properly speaking, is accessible only two or three times a day and only for a short time cor- responding to the compass of the working of the plant; a proportion of moisture in the atmosphere of the refrigeration room can only be attained if only the fresh meat and fat of the slaugtered animals, which have already been prepared in the preliminary cooling chamber, is allowed to be brought into the refrigeration room. It is to these principles that the provisions generally conform, which regulate the working of the refrigeration and preliminary cooling rooms, that is to say, the regulations prescribe certain times for opening, and in properly and efficaciously conducted refrigeration plants they only allow the admission of fresh meat and fat in the cooling rooms, but they do not permit the admission of intestines: Lungs, livers, hearts, milts, stomachs, fresh or salted guts, salt meat etc. - At the I. international refrigeration Congress the following axiom was established, among others, by Heiss-Straubing and accepted by the Congress: «It is forbidden to store entrails, hides or any malodorous things in the refrigeration room”. But this demand urged by the Congress, in connection with my previous observations involuntarily suggest the question: “Is it then unnecessary to preserve the intestinal organs which as well as the meat and fat of the slaughtered animals are put upon the market as a nutriment for man both in a fresh and prepared State and which represent a not incon- siderable value ** It is not hard to find an answer: “It is just the intestinal organs of slaugh- tered animals which are very greatly in need of preservation in refrigeration rooms, because they putrify far more rapidly and easily and because they are far more liable to be defiled by insects (flies, maggots) than fresh meat and fat. Now, as the storage of the organs of slaughtered animals, by reason of the large proportion of moisture they contain, is out of the question in a properly conducted refrigeration plant, when the preservation of fiesh meat and fat is at stake, and as the dealers in meat and provisions have no sui- able premises at home for the storage of the said organs, it follows that a special cooling chamber will have to be supplied in a refrigeration plant which is expected to answer every hygienic and technical requirement. Such a cooling chamber in which, the same as in the meat cooling chamber, a temperature of from 0 to + 4°C would be the most favourable, would only answer its purpose perfectly in a sanitary respect, if the organs — lungs, hearts, livers, milis, stomachs, guts – could be brought into the cooling chamber in summer as soon as possible after being slaugh- 492 tered, i. e. after examination — when still warm — in order to prevent the disgusting defilement by insects. But by complying with these demands the proportion of moisture in the air of such a cooling chamber would be so much increased as to make it the duty of the technique of refrigeration to reduce that high degree of moisture by suitable means with out a mate- rial loss of cold to the measure required for a hygienically unobjection- able and economically advantageous preservation of the organs, The arrangement of a cooling room for organs would be the same as for that of a meat cooling room — cells —, except that the cells would be Smaller in proportion; the lessee of a cooling cell in the meat cooling chamber would be, as a matter of course, the lessee of the cell with the same number in the cooling chamber for intestines. *~. It would also be advantageous to put into such a cooling chamber, in addition to the intestines, the flesh of such animals as remain in their skins for reasons of economy in professional slaughter. The storing of the flesh of such animals in the p' oper refrigeration chamber would not be advisable on account of the odour of the skin — at least So long as the flesh remains in the skin — and it would therefore be prohibited in most of the refrigeration plants. t By what I hear, there is no special cooling chamber of this kind as yet for organs and the flesh of animals in the skin in any of the existing slaughter house cooling plants, but my explanations, which in accordance with the way usual at international congresses, are worded bricfly and conc- isely, are likely to show the necessity of creating cooling chambers of this kind. The storage of salt meat, Salt guts etc. in rooms provided with special appliances (so-called pickling rooms) would not be affected by the rcquire- ment of a cooling room for organs etc. It is advisable to locate the pickling rooms apart from the cooling rooms, because they should have a tempera- ture suitable for the pickling of meat from + 8 to + 10" C, whereas the cooling rooms should have a temperature of from 0 to +4° C. - * In conclusion I wish to mention the arrangement of refrigerating rooms for game, poultry and fish and of cooling chambers for milk, eggs, butter etc. Unfortunately, hitherto the necessity of establishing such rooms has not received the desirable attention from the municipal administrations, which I attribute to the fact that the managers of slaughter houses, being the most competent advisers of their municipal authorities, have not yet given sufficient- attention to this subject. As soon as such rooms have been arranged in several towns and their expediency, in addition to their lucrativeness, has been established, then also will there be an interest taken and such refri- geration, and cooling rooms will be established in the towns, from which the inhabitants can be plentifully supplied with game, poultry and fish on the one hand and with milk, butter, eggs and similar articles of food on the other hand, which may all be advantageously preserved in cooling rooms. 493 Sum m a ry: 1. The internal organs such as lungs, heart, liver, lights, stomach, inte- stines of slaugh t e red a nim a 1s which are used as food for man and which represent a not inconsiderable value, require to be preserved in cold air storage chambers just as much as the fresh meat and fat of these animals, because they are much more exposed to the danger of becoming rotten, or of undergoing decomposition through insects, than fresh meat and fat. 2. The most suitable way of preserving these organs is to keep them in special chambers kept cool by cold air: a) because on account of the amount of moisture contained in the organs it is out of place to store them in the same chambers as the fresh meat and fat, and b) because they should be put in cold air storage chambers as soon as possible after their examination, in order to limit or prevent as far as possible the disgusting pollution in the above mentioned organs, caused by insects. 3. In cold storage chambers for organs the most suitable temperature is the same as that for fresh meat and fat; namely, 0° to 4° C (32° F to 39.2° F). …” 4. Endeavours should be made to adapt the amount of moisture in the cold air storage chamber to the amount of moisture in the organs in such a manner that a hygienically unobjectionable and a profitable preser- vation of these organs results. 5. Animals, which for business purposes are kept in their skins after slaughtering (e. g. calves) are most suitably preserved in the cold storage chambers for the organs, because in consequence of the unpleasant mells coming from the skin they are not suitable for preserving in the cold air storage rooms for fresh meat and fat, and because the greater amount of moisture of the air in the cold air storage chambers for the organs prevents the unprofitable drying of the flesh of such animals. s 6. For sanitary as well as economical reasons endeavours should be made to create cold air storage chambers in connection with the municipal slaughter-houses for game, poultry fish as well as cold storage chambers for butter, eggs, milk and other provisions that can be with advantage stored in such cold storage chambers, whence the population in a large surrounding area can be supplied with such provisions. * 7. The cold storage installations of modernly equipped slaughter- houses of middle sized and large towns must, accordingly, have the following premises for the preservation of perishable food: 494 a) Entrance Porch; b) Cold air storage chamber for fresh butcher meat and fat; c) Cold storage for the internal organs of animals and for animals that have to remain in their skins after being slaughtered; * d) Pickling and Salting chamber; e) Freezing chamber for game, poultry and fish; f) Cold storage chamber for milk, butter, eggs and for those articles of consumption for which cold storage is necessary. 495 Concerning the Management of Cold Storage Plants. By Prof. E. Jalowetz, Vienna. The control of cold plants is in general too little considered, and too carelessly exercised; it deals chiefly with the source of the cold, or the moments to be observed during the working; on the other hand, to the least degree, with the refrigerant. A sharp distinction between the machine technical and chemical tech- nical control cannot, indeed, be drawn, yet the present paper takes the latter principally into consideration. As refrigerants air, water and salt solutions are employed. Of these only the latter will be treated of here. The salt solution must not contain any solid elements, or any impu- rities; it must have a definite concentration, and a favourable specific heat, and finally it must not attack the conduits. The normal content for a common salt solution is 20%; this solution has a density of 1:150 and a specific heat of 832. The normal content of a chloride of calcium solution is 22°lo; this solution has a density of 1°105, and a specific heat of 770. The preparation of the generator liquid may never take place in the evaporator, and the salt solution that is introduced into the evaporator must be clear. For the denaturalization of common salt from one to three kilos of calcinated soda are used to 100 kilos. of common salt, or for chloride of calcium 5 kilos. of sodium hydrate to 100 kilos. of chloride of calcium. During working the following controlling tests must be made: 1. Measurement of the salt content with the aid of an arãometer. 2. Measurement of the soda content by means of titration. 3. Ascertaining the specific heat, if the liquid does not possess a uni- form composition. 4. Determination of amount of impurities by filtration. * 496 The testing of the salt content is provided for in the usual working º regulations; yet even this very important control is but too often neglected. The control of the soda content, of impurities, of the specific heat is very seldom carried out. The most important is the examination for im- purities. - The presence of impurities may be due to two causes; either they have been introduced into the generator with the salt solution, or they have arisen in the conduit system through mechanical and chemical effect. In the latter case the suspended elements, as also the coating of the conduits caused by them, as has been proved by many experiments, consist of feroxy- hydrates, namely, up to 80%; the other elements are alkalies and other mineral earths. The circumstance that the salt solution often circulates for years wit- hout filtration of the brine and cleaning of the pipes, may result in the for- mation in the brine pipes of coating to the thickness of several millimetres, thereby enormously reducing the cooling effect. I have repeatedly had occa- sion to observe coatings up to 6 mm. in thickness. It is urgently necessary to overcome, or, rather, to prevent this evil; and this may be done by using pure brine solution, by continually filtering the salt solution circulating through the pipes, and finally by annual mechanical cleaning of the inside of the pipes by flushing with water or by brushing. To lessen the corrosion of the pipes it is to be recommended that piping be used which is tinned inside and outside; these are, according to experience, preferable to black or asphalted pipes. According to the foregoing a brine filter is an indispensable part of every cold plant. It must be built in behind the cooling pipes, and it is ad- visable that machine factories should always reckon a brine filter as normal part of a cold plant. The chemical technical examination must be applied also to the refri- gerants, the condenser water and the compressor oil. The refrigerants, such as ammonia, carbonic oxide and sulphuric acid, must be tested as regards their purity. The impurities are water, alcohol, pyridine bases and organic matter. For the testing the customary chemical methods must be employed, though for ordinary practical purposes evapora- tion methods suffice. - { The content of impurities must not exceed 1% in the ammonia taken from the machine for testing. Ammonia when bought contains 1 to 5"/, of impurities. The condenser water forms the indicator of the density of the con- denser Serpentine pipes, and it must be tested for an eventual presence of ammonia and sulphuric acids. The methods are those usual for testing Water. 497 . As regards the compressor oil it must first be pointed out that this as regards its composition and condition must form a good greasing oil. A special test is given by the compressor oil at congealing point, which is to be effected in the ordinary manner. In practice it suffices to effect the test in such a manner that some cubic centimetres of the oil in question are sunk into evaporating ammonia, in a test tube. Precipitation must not follow. Besides the freshly drawn oil the purified compressor oil gained must also be tested, and that, not only as regards its quality, but also as regards the quantity of oil gained. The tests here mentioned should be regulary applied in every cold in- stallation, and recorded beside the working data. 3 2 498 * Cold Storage for the Suburbs of Paris and the Provinces. By Mr. Francis Liernur. The company which I have been asked to represent at your very honour- able and learned assembly is quite new, it will be completely established this month. -- • . Encouraged by the ideas which have emanated in profusion from such eminent and public spirited men as Messrs. Lebon and de Loverdo, a number of active and energetic men have joined to build up in France, near Paris, a refrigerating plant which they hope to make second to none, and which is to have the most perfect equipment obtainable. It should be noted that it is only in very recent times that the new ideas of cold, as applied to the preservation of foodstuffs, have taken root in France. But we may say without presumption, that, when we in France try to do a thing well, we arrive at perfection. . - - Therefore, literally following the interesting work and advice of the men of science of whom I have just spoken and availing themselves of a great amount of experience derived from the immense progress of neigh- bouring nations, the company which I have the honour to represent has left nothing undone in spite of the exorbitant cost of the franchise to install a. refrigerating plant at the port of Paris at Epinay on the Seine, on municipal territory, having an available space of 10,000 cubic metres. This installation is intended for the reception of all kinds of perishable goods, whose preser- vation, I repeat, is assured by the most rational and perfect equipment. Doubtless this is already something, but more must be done, and other facilities must be given to dealers in perishable goods. Long idleness of capital, which causes so much trouble, must be avoided; producers and ex- porters as well as middlemen must be in a position to profit by the un- doubted advantages of cold storage; all must be able to avail themselves of a cold store so that their merchandise may, without any misapprehension, await a favourable time for sale. s Our company makes it possible for anyone to profit during the favou- rable seasons when there is a surplus of perishable products. 499 So that the owner of the produce stored up, having a large part of his capital still available for use, is able to carry on his business and wait without anxiety until the market price allows of his selling his produce at the greatest profit. To accomplish this, many precautions must be taken, because the inte- rests of consumers must be safeguarded. For this purpose our company has decided to appoint a special expert for each kind of produce; this expert is to give information on the quality of the goods recieved, and upon which the most liberal advances are immediately allowed. This, Mr. President, is a real and effective organization for storing pro- duce, and we are thinking of doing still more by appointing other experts, whose business is not less important, consisting as it does in gathering all available information as to the state of the market, the probabilities of high or low prices, and laying it before any customers who wish to avail them- selves of our system. Thus as you can see it is quite an innovation in cold stores, and I can convey the assurance now, that no effort is spared to give the best guaran- tees to any dealers interested in our plant. It is also of great importance that our Epinay depot has special rail facilities and is situated at the intersection of the Northern Railway and the great Ceinture de Paris.<;. so that cars, no matter from whence they arrive, may enter or leave directly without the goods suffering from contact with the atmosphere. Such is a brief description of the organization, Mr. President, which I put before this honourable assembly. Entirely in agreement with the eminent experts and practical men who have attended the Second Inter- national Congress of Refrigeration in such large numbers, I believe that it is of the utmost necessity for the benefit of the public to apply ourselves to the use of cold in connection with alimentary produce. 323; 500 The Application and Arrangement of Ozone Apparatuses in Cold-rooms. By Professor Alois Schwarz, Mährisch-Ostrau. The experience of many years in the management of cold-plants, especially in slaughter-houses and cold-store-rooms for food stuffs, has shown that in spite of the greatest and most correct cooling smells arise at times in the cold-rooms. Such appearances rest upon the fact that the microcosms which cause the decay and spoiling of the food are not completely destroyed by the action of the cold, but are merely hindered in their development and increase. * Such further development and increase with their decaying effect set in if the necessary temperature and moisture of the air in a cool room is departed from but for a short space, or if the cooled meat be temporarily removed from the cold-room and again replaced in it. The moisture in the air in a cold-room is deposited on the stored goods, these are thereby warmed and through this the micro-organisms are developped and the evil smelling products of decomposition are formed, and . the air of the cold-house thereby deteriorated. -- The so-called flesh smell thus formed in abattoirs and cold installations can never be entirely avoided; there has been, hitherto, but one means of keeping the air of a cold-house fresh, and that is the continual or periodical introduction into the cold-house of fresh air from outside, and this method : naturally necessitates the employment of fairly considerable quantities of cold, which greatly increases the working expenses, even as much as from 10 to 15 per cent. A similar phenomenon is observable in the ferment cellars of breweries and at dairies, though the disagreeable smells only arise to a slighter degree. The use of the customary desinfectants to overcome and prevent the unpleasant smell in cold-rooms proved unsuitable for food and epicurean goods on account of the generally poisonous properties and the still stronger Smell of such disinfectants. Recourse has therefore been had in latter years to a chemical agent whose powerful oxidising and dis' fecting effect, combined with harmlessness for the goods destined for human consumption, has been long known and tried, namely Ozone. 501 It may be taken for granted that the chemical properties, the effect and the methods of obtention of this modification of the oxygen always existing in the air are generally known, so that a detailed explanation thereof may be left out of the question. Ozone is the active form of oxygen which is distinguished from the ordinary form by the fact that its mole- cules consist of two atoms of oxygen and a third atom which in conse- quence of its labile character cannot easily be separated from the molecule SN 2 & --- :i× : # -y H. ; - Plate 1. Ozone apparatus, System Siemens & Halske. and exercises a powerful oxidising effect which is especially active in destroying micro-organisms and the gaseous products of decomposition caused by de- composing Organic matter. As is known, Oxygen is formed in numerous chemical processes by the separation of oxygen from higher oxygen, further by rapid evaporation of water under the effect of the rays of the sun, and particularly easily and rapidly in cases of powerful electrical discharges, by which phenomena the fact that ozone is always found in the air, and the refreshing effect of forest air, mountain air and sea air are explained. 502 For the wholesale production of Ozone only electrical discharges are made use of; either spark or still more effective, so-called dark or glimmer discharges, which only occur if a so-called Dielectric, a nonconductor made of glass etc., be placed between two high tension electrodes, whereby a direct passing of sparks is hindered and replaced by a weak bluish glimmer. This part of the requisite apparatus shall be explained later on. (Z & ts | | | T Tºlº |||||||||= i | III]º *: # # t | # Léºll | ~f~ || || ill llllllllllllllllllllllllllllll lif' Hrt | £ 3 | -vºm- _*- : {–––––. } ſ -—— § I-—T-—— –4 – *m- s H- | ! / T---- ——1– Plate 2. Air ozoniser (Siemens & Halske), combined with airing plant. For many years, already, exhaustive experiments have been made at the imperial Office for public health of the Empire and at the Institute for infectious diseases in Berlin, concerning the effect of Ozone on micro- organisms. These showed that water which contained millions of pathological germs, even of Typhoid and Cholera, could be made entirely free of germs -- 503 by chemical treatment with Ozone. These experiments led to the first practical application of Ozone for the sterilisation of water for drinking purposes, which process of water purification was perfected and successfully introduced into practice by the firm Siemens and Halske A. G. in Berlin, on the basis of trials conducted during many years. Further experiments proved that by electrical ozonisation a great re- duction of the germs in the air could be effected and that ozone was con- sequently one of the most suitable means, through its oxidising qualities, of freeing the air of micro-organisms and of disagreeably smelling products of breathing and decomposition. Ozonisation of the air was first made practical use of for purposes of air purification in meeting rooms, theatres, concert halls, hospitals, rooms on ships, factories, inns, Cafés, for which pur- poses several electrical firms built suitable apparatuses and introduced them with very good success, as, among others, in the plant at the Friedrich Wilhelm- Plate 3. Ozone apparatus (System Ozonair), in shape of battery. städtischen Schauspielhaus in Berlin, at the law Courts in London, at the Bank of Commerce in Glasgow, the German Bank in Berlin, the Casino at Nice, Piccadilly Hotel in London, Café Pallant in Cologne, the hospitals in Milan and Pavia, in the Town Hall in Vienna, etc. The application of Ozone for the purification of air in cooled rooms was first tried in the Brewing industry. Professor Dr. Will lectured at a meeting in the scientific station for brewery, in Munich, held in April 1908, on trials conducted with the introduction of Ozone as disinfectant in the brewing industry. These trials showed that Ozone if properly applied for- med a very suitable disinfectant for brewery purposes. For these purposes first consideration is demanded by the purification and betterment of the air in ferment cellars, as also in the drizzle coolers, and for these purposes the application of ozonisation apparatuses already known is sufficient. 504 As agent for disinfecting premises, for the sterilising of metal piping (wort or beer piping, in so far as it is not connected with rubber piping)," and of store barrels, if such are to be purified on the spot, ozone would be of greater importance even than for the destroying of germs in the air in cooled rooms. • * - Further trials were made with Ozone air in the milk industry, which were carried out by comparing observations in the storing of cream in ozonised and ordinary rooms. In ozone rooms fresh cream remained un- changed during 3 X 24 hours, in ordinary rooms only 24 hours. Butter kept fresh in Ozone rooms for four weeks while in ordinary rooms it had taken on a stale, rancid taste after but three days time. Therefore the ozoni- sation of butter store-rooms might offer the possibility of maintaining in the w Schsklafel - sts Regouver was r- unformvry stand ºf vent later | #!/. j - <+- Osow\{tlest.ns - * Ozon-LUFTUNES ANLACE, Avs. gºvt ov; dicinv panpſet JMAK URA* Eltºr.cº.:-3.uke ºv * . FE Schaltta t tº - º M |W der Newswtawa ps wººfschaffgesel) schaft . f *º-e £rºr - Crum driss. º - - Ansicht. #IºIII; ºul wformt r Plate 4 ozone airing plant, System Ozonair. butter its fresh flavour for fairly long periods. The ozonisation of the air might also play an important rôle in the preparation of cheese by destroying harmful germs. - - - - Very good experiences were made in fish stores. In the Jubilee Cook- ing Exhibition at Berlin, on the stand of the North Sea Fisheries at Cux- haven there was a 3–6 metre-centners ice bed always covered with sea- fish, and the particular part of the hall was ozonised by means of two ozone-wall-ventilators by Siemens and Halske, A-G. In spite of the enorm- ous number of visitors to the exhibition and in spite of the very un- favourable conditions of air and temperature, there was never a noticeable disagreeable smell of fish, whilst such smell became at once evident when the ozone ventilators were stopped. The air of this part of the hall remained always fresh and even the food exhibited near the fish stand kept fresh longer than that in the other parts of the exhibition. The deodorizing of 505 sea-fish-shops by this method of applying Ozone would probably put an end to the aversion of many people to sea-fish on account of the unplea- Sant odour. The fish shop Grand and May at Billingsgate, London has for this purpose ozone apparatuses of the Ozonair Co. Ltd. already in work, and the fish merchants Hofbauer in Vienna have such made by Siemens and Halske, A.-G., of Vienna. It is, also highly to be recommended that such ozone apparatuses be employed in cold installations at mortuaries and in corpse preservation at hospitals. Ozonisation of the air, as far as trials hitherto made are concerned, has given the best results at meat cold - halls. Such trials were first con- ducted at the abattoirs in Frankfurt am Main and Cologne, under the super- vision of experienced scientific experts. In Frankfurt am Main, where the meat cold-rooms are extremely unfavourably situated in subterranean cellars, So that no fresh air whatever can be introduced, but the air has to be sucked in by ventilators and purified by the cooled brine, very good results were attained by the use of air ozonisation plants as regards the prevention of the flesh smell. In the abattoir at Cologne. a calf destined for slaughter which was already covered with mould and had partly decomposed was treated with Ozone; the decomposition was entirely stopped by this process. A piece of * free-bank-fleshk, which showed mould between the bones, after three days' Ozone treatment, showed a reduction of the mould and after cooking had the Smell of perfectly fresh meat, whereas the meat not treated with ozone had a disagreeable smell after the same period of time. Thereupon the ozone apparatus was allowed to work over the whole cold-house. At first, about half an hour daily for eight days, the apparatus was allowed to work in the cold-house; accordingly about 21/, grammes of Ozone were daily introduced into the cold-house. This process had an astonishing effect upon the cold-house. Every kind of smell in the cold- house, especially in the cold-rooms in which lungs, livers, heads and entrails were kept, vanished. Bacteriological experiments were then instituted as to the purifying effect of ozone in cold-rooms and air-coolers, namely just before ozonisation and just after half an hour's ozonisation. Plates were inserted in the canal behind the air cooler and behind the introduction pipe of the ozone apparatus during half an hour. It was ascertained in five fairly coinciding trials that on the short way in the canal, by the introduction of the ozone, about 50 per cent of the germs had already been destroyed. It may be supposed that there was still a certain surplus of ozone, for on the short way the dry burning of the germs could not have taken place completely. It was found after the first trials that so remarkably few germs were present in the cold- rooms in comparison to the former considerably large quantities that for 506 - the first time no clear picture could be formed of the effect in the cold- rooms. Through the introduction of ozone into the cold-rooms during eight days, in every case, the germs existing on the walls, on the air piping, on the floors and in the flesh were all destroyed, so that the air of the cold- house appeared practically sterile. In the other trials therefore the air of the cold-house was for a whole week not ozonised, and also no fresh outer air was introduced. After a fivefold series of trials there was then still a remark- ably low number of germs in the air, in comparison to the results attained before the ozonisation. After half an hour's working of the ozone apparatus the quantity of Bacteria in the plates, as compared with the series of trials in which ozonisation was not carried out, was also found to be 50 per cent lower. º - ºf º Plate 5. Ozone apparatus (System Lahmeyerwerke). As these trials were first made in October they cannot give any abso- lute conclusion as to the real bacteriological purification, but at all events it can be deduced therefrom that the air became vastly purer and better. Extensive bacteriological experiments were conducted last summer by Dr. Fiede, the abattoir bacteriologist, of which no final reports are yet to hand. Since the ozone apparatus was first introduced every kind of intro- duction of fresh air to the cold-house was stopped. Whereas formerly, in order to maintain a certain over-pressure of air in the cold-house a small quantity, about 1000 cubic metres per hour, of fresh air was introduced this remained in abeyance during the trials. It will not be possible, however, to do without the introduction of fresh air during summer when the cold- house is opened for traffic, as then, through the keeping open of the doors 507 of the cold-house the unpurified outer air will enter. Yet these trials have proved that during the time in which the cold-house is closed to traffic, it is possible to manage entirely: without the introduction of fresh air. The saving in cold and coal resulting would be a revelation. As such good results were attained with meat, ozone was also introduced into the egg store-rooms, of which there are about 500 square metres in the particular cold-house and which are cooled by a special air-cooler. It was already Plate 6. Ozone apparatus (Lahmeyerwerke), with ventilator. evident, after but a quarter of an hour, that the specific smell, of musty straw or wood, noticeable in the egg cold-rooms after about three to four months, had completely vanished. Ozone was therefore introduced into these rooms for about a quarter of an hour each week, which proved absolutely harmless to the eggs. As it is naturally of the greatest importance for the preservation of the eggs that they are stored in sterile air and in sterile packing, ozonisation of the air of the cold-house can only be of ad- vantage. 508 Equally favourable results were obtained by the working of the ozone plant set up by Karl J. Busch & Co., in the course of last summer, in the freezing and cold-house centres in Berlin, as also the plant in the fish market at Christen's in Basle, after the system Ozonair, set up by J. A. Si- monet of Mühlhausen in Alsace-Loraine. It may therefore be decided on the basis of the foregoirg experiments that it appears to be of the greatest advantage to attach an ozone apparatus to a cold-plant. Though these experiments have only been made in a plant with so-called dry cooling, yet the ozonisation may be advantageous to a higher degree in a so-called wet-air cold plant. Here, however, the ozone would have to be introduced before the air-cooler, in order that the salt late 7. Construction of the Ozone airez, System Lahmeyer. water be made sterile and odourless by the ozone introduced in passing through the brine-rain. Then the separation of fresh salt could be spared and the brine again vapourised. Apparatuses for the ozonisation of the air are built by many firms, and the best known shall here be described shortly with the aid of the illustrations. The apparatus built by Siemens and Halske A. G., in Germany, whose Hamburg agents are Karl J. Busch & Co., is constructed on the following principles: A metallic cylindrical inner pole is surrounded at small distance by a glass cylinder against which is placed a metal plate that serves as outer pole. The inner pole lies on one high tension pole of an alternating 509 current transformer, while the outer pole with the apparatus chamber as also the high tension pole of the transformer are grounded for safety. Between the cylinder and the inner pole is the discharge space through which the ozonising air must be driven. The arrangement here described is . an ozone tubular element, and of several such elements an Ozone apparatus consists. In the Cologne plant there is an apparatus at work consisting of eight tubular ozone elements. This stands on a wooden bracket, in which the transformer, also, is built, secured against possibility of being touched by any unwarranted hands. A blower is employed for driving the air and presses 10 cubic metres of air through the ozone apparatus every hour; this air, so ozonised, then enters the cold-room that is to be aired. To produce the alternating current, that must be conducted to the transformer a small alternating dynamo is employed which is driven by a continuous current motor. For building into the shafts of a not too large central airing plant, air ozonisers are most suitable. These are trellis-like apparatuses consisting alternately of a small metal bar surrounded by a glass tube (Dielectrie) and a metal plate. The whole trellis is surrounded by a strong frame which can be built into any shaft without difficulty. All the plates which form one electrode, lie on the high tension pole of an alternating current transformer and are well isolated from the frame. This together with the bars forming the counter electrode, and the second high tension pole of the transformer are grounded for safety. When the apparatus is working electrical exchange takes place between the bars and the plates, and as above mentioned, forms glimmer discharges. If air is driven through this trellis a part of its oxygen becomes ozone, and this Ozone air is carried by the shaft into the rooms that are to be aired. The management of air ozonisers is very simple. An advantage of it consists in the fact that it ensures a permanently good distribution of the air. The whole apparatus occupies but little space, and is made in various sizes so that it can be adapted to every section. For large and much branched airing plants it is to be recommended for various reasons, among others also for economical reasons, that a different method be followed. At a central point highly concentrated ozone should be produced, by means of large apparatuses called 3 Ozonestationen < and this mixed with air is introduced into the rooms either direct or through the airing canals. The air is in this case passed through the ozone apparatus and into piping by means of a blower. The ozone-air then mixes with the other air in the air canals, or in the rooms themselves, so that the necessary concentration is reached, which according to latest experiments should be about 0.5 milligrammes per cubic metre of air. The ozone apparatus constructed according to the system Ozonair Limited, London, built by J. A. Simonet, Mühlhausen in Alsace, and re- presented in Germany by Val. Allut Noodt, in Hamburg, shows a similar arrangement, and the ozonisation is effected in this apparatus by dark dis- 510 charges of the highly tensioned alternate current between the electrodes separated by glimmer plates. The periodical ozone concentration can easily be regulated by a regulating starter. The ozonisation battery calculated for the periodical change of air is placed somewhere in the room that is to be aired; the outer air is sucked in by means of a ventilator, pressed through an air filter to clean it of dust, and passed through the ozonising battery. An apparatus can also be made transportable for rooms of 200–800 cubic metres. The accompanying sketches show the arrangement of a plant arranged for the ozone airing of a ship's cabin by this system. Apparatuses according to the above mentioned Plate 8. Ozone wall ventilator (System Siemens & Halske). systems are shown in work at the Sports Exhibition in the group • Wild- verwertungs. A third system of ozone apparatuses is built by the Lahmey, Werke A. G. in Frankfurt am Main, and is also distinguished by simplicity of con- struction. The ozone ventilator and ozone exhauster consist of ventilators driven by electric motors which are built together into one apparatus with the ozone producer and the transformer. The ozone airer consists of an iron frame fitted with ozone trellis and with a transformer attached. The application of the above described ozonising apparatures can take place in various ways, either the transportable apparatus is plºed directly in the room that has to be aired or, if there is an air canal, tº apparatus can be built into a branch of this canal. diº Generally, however, in cold-rooms an ozone-station is provided, that is, an apparatus which produces concentrated ozone air, which is then by means of piping conducted to the different places as required. For instance they are conducted into the pressure canals of separate cold-rooms, where they mix with the circulating air of the cold-room and thereby ozonise this and, as a result, also the cold-house goods. If an air-cooler is not provided with air revolution, the ozonised air must be distributed in the room by means of a ventilator, or a special air revolution is arranged for thoroughly mixing the ozone air with the air of the cold room. In most cases a daily or at most twice daily treatment of the air of the cold-room with ozone will do, which according to the size of the rooms lasts - Plate 9. Removable Ozone apparatus (System Ozenair). from a quarter of an hour to at most an hour, so that one ozone-station can used consecutively for a large number of cold-rooms. The costs of workfºg are vanishingly slight, as for 1000 cubic metres of air per hour the current used up only amounts to about 30 watts, i.e. less than the amount used by one glow-lamp. The ozonisation of the air in cold-rooms may certainly be described as one ºf the greatest steps forward that have been made in the progress of cold technics during late years. With the simplest means imaginable it solves a task, the purification of the air in cold-rooms, for which hitherto great a unts of time and of cold were necessary. The ozonisation of the air in co, -rooms will, therefore, certainly prove in future one of the most indispens le requirements of a cold plant for the preservation of food stuffs. 512 One method of applying ozone in cold industries should finally be mentioned, and that is the purification, or sterilization of water, spoken of at the beginning, by means of ozone, for purposes of ice-making. Absolutely Plate 10. Ozone plant for water sterilization producing until 10 cubic metres per hour, System Siemens & Halske. germ-free ice, destined for consumption purposes, could hitherto only be made from entirely faultless drinking water, or where such was unobtainable, from distilled water. For this expensive plant and the use of great quanti- ties of steam were necessary. By treating any water, even water containing 513 germs, with ozone, the organic impurities and all germs therewith are destroyed, and through this the quality of the water as also always that of the ice manufactured therefrom will be hygienically perfectly unobjectionable. - The ozone requisite for sterilizing the water is produced by a similar method, with specially constructed apparatuses, by dark electric discharges. The accompanying illustration shows the arrangement of an ozone plant for water sterilisation, according to the system • Siemens and Halske, for an hourly production of 10 cubic metres. . . . - | Such plant consists of CzoNWASSER-STERILISATIONS-APPARAT circulationshahn. 2 := | º # | 3freimar | || || º i ! . : l Qzz-circulatiºnnºr : |Ž - Aftº: - -ºilermºr. #|| 3: i ! #: gi sº ; -ºr Ár &ſºrpe is & - . :======7 - - Aſthalappa- tºster. Plate 11. Ozone water sterilization apparatus, System Ozonair. - 1. a sterilization tower filled with shingle and formed scrubber-like, in “. . . . which the ozone-air meets the water flowing through the shingle in counter stream; - - . - 2, a machine placed on the ground with continuous current motor, which by direct coupling with an alternating current machine and by band transmission drives simultaneously an air-blower and a water-pump; 3, a bracket, on which stand two ozone boxes, already described, each with eight ozone tubes and on which, too, by the side of the electrical measuring instruments and switches for the transformer prime current circle, - a transformer is built ; 33 514 4. a switch board with shutting off switch, tension register, current safety arrangements, as also, lying below, a starting register for the electric motor and register for the inducting current circle of the alternating current machine. - The plant is also provided with electrical safety arrangements, which automatically shut off the flow of raw water to the tower, if the tension of the transformer driving the ozone apparatus sinks somewhat or ceases, or if the stream of ozone-air flowing through the apparatus falls below a definite limit, or fails altogether. Another illustration shows the arrangement of the system of Ozonair Limited, London for ozone sterilization of water, working with similar con- struction, in which the tower that serves to distribute the water flowing down over the ozone, for the sake of an even combination with the ozone air, is filled with suitably large glass balls. This execution of the sterilizing apparatus has also proved very satisfactory in actual working. This use of Ozone, too, in cold industries will probably soon become general on account of its many advantages, and the attention of all experts should be directed to this improvement, which is as yet but little known in ice-making. 515 The Abattoirs and Markets of Prague. By M. Em. Stehlík, docteur en droit, Conseiller and Rapporteur. We have the honour of presenting to the International Refrigeration Congress a report upon the use of artificial cold in the central abattoirs of the City of Prague and in the City Market. Abattoirs. The central abattoirs and the animal Market at Prague in the 7" arrondissement (Holešovice), opened on the first of July 1895, are furnished with a cold store. --- As elsewhere, it is hardly 20 years since the Societies of butchers at Prague (Společenstva feznikū) possessed special slaughteries (porážky), and before the opening of the public abattoirs, there were in Prague, several slaughteries belonging to the societies of butchers at Prague, who worked them under the control of the municipal authority of Prague (Magistrat). The abattoirs of Prague and the animal market have retained the chararacter of public etablishments (municipal) constructed on modern lincs by the City of Prague, conforming with the Bohemian Law of March 9th 1889 (No. 19 of the official bulletin of the Kingdom of Bohemia) and the obligation of going there for the slaughter of cattle is imposed by the said law upon the butchers in the communities near Prague (Prague with 16 communities). As may be seen in article 3 of the said law, the central abattoir which it concerns must be furnished with cold rooms (chladírny). The cold rooms of the abattoirs of Prague situated at the side of the market intended for the sale of the meat wholesale, covers an area of 300 square metres (entresol); this cold store was not divided into compart- ments, there is only a store furnished with 800 hooks. But later the necessity became evident, of constructing in this store 14 compartments of 6 do 12 square metres each, and of increasing the number of hooks by 360; of electric light in the cold store. Rent of these compartments 400 do 800 crowns per year. The rooms are cooled by machines on the Linde system (ammonia), the cold rooms are open to the public only at times fixed by the administration of the abattoirs, and at the same times as the abattoirs; the refrigerator will only take in meat already cooled, not warm, and such meat from animals killed at the Prague abattoirs has the preference of meat from any other Sources which may only enter the cold store after a sanitary inspection (vete- rinary). The regulation relating to the use of cold stores is contained in the 33% 516 regulations of abattoirs (Rád jateční) and consists in a single article (28th). This regulation was made by the municipal council, on the suggestion of the administrative council of abattoirs, and approved by the municipal prefecture (Magistrat) on the 24th of July 1901. The rent of the hooks in the cold store is fixed by a special tariff (20 crowns per hook). i After 1903 the Administration of Abattoirs took up the question of enlarging the refrigerators of the abattoirs, or rather of the construction of a modern refrigerating store, having a capacity of at least 360,000 kilogrammes of meat, and furnished with a refrigerator which cost from 500,000 to 600,000 crowns to construct. Maker of the Machinery: Českomoravská towārna of Prague VIII and F. de Ringhoffer Prague-Smíchov (Engineer: M. Jean Fille of the F. de Ring- hoffer Company). - M. Venceslav Feigle, engineer of the City of Prague, was entrusted with the inspection of the work. The receipts from the rent of the cold rooms of the abattoirs, for the year 1909, reached 12.671 crowns 42 hr. The commercial progress of the central abattoirs of Prague. In the eight divisions of te City of Prague were counted 444 butchers (in 1908). - - ~ In the district of Prague, and in four suburban communities, (Karlín, Smíchov, Vinohrady, Žižkov) were counted 969 butchers in 1908. Average number of animals Slaughtered annually in the Abattoirs of Prague. Cattle . . . . . . . . . . . . . . . . 24,000 Sheep . . . . . . . . . . . . . . . . . . 21.000 Heifers . . . . . . . . . . . . . . . . . 5.800 Pigs . . . . . . . . . . . . . . . . . . . 360,000 Horses . . . . . . . . . 2,500 There is good reason to hope that all the communities in the neigh- bourhood of Prague, mentioned in the act of 1899, will shortly accept the statutes drawn up by the committee of delegates of the communities, and already voted by the Municipal assembly of Prague, concerning the centrali- zation of the abattoirs and meat markets; a combination will then be effected to create a large central establishment for slaughtery and veterinary inspection for Prague and the neighbouring towns. Up to the present there exist near Prague the abattoirs of Karlin, Král. Vinohrady, Smíchov and Žižkov. º The Markets of Prague. The Stores of Prague, or rather the City markets (Staroměstská tržnice) have not the character of wholesale markets and central stores, because the provisioning of the city is also assured by several open provision r markets. 5 1. 7 Staroměstská tržnice, installed in the spacious court of the municipal buildings (No. 406-I), occupies an area of 3715 Square metres. The con- struction of several stores or covered markets in Prague was foreseen, but these projects have not up to now been realized. The Stores of the city are principally devoted to the retail of foodstuffs. The underground cold rooms are divided into compartments. The machinery is constructed on the Riedinger system. There are no freezing rooms in the Stores of Prague, because the foodstuffs do not require a temperature as low as —2° C. Concerning the rent of the compartments and divisions of the cold rooms, the Municipality of Prague has drawn up rules and special tariff (article 20). The commercial progress of the markets of Prague. The statistics of merchandise dealt with by the Staroměstská trznice Stores in 1909 (progress during the year 1909 was exceptionally little, especially in the case of poultry and game). 35,000 lambs, kids and Suckling pigs. 353,000 geese, ducks, capons and turkeys. 470,000 fowls and pigeons. 253 deer. * 3.820 roes. • 65.600 hares. y . . . . 10.800 pheasants. . 13,000 partridges — snipes. 3,000 kilogrammes of fish. 10 000 kilogrammes of butter. 23,000,000 eggs. The City markets comprise 360 rooms and were opened on March 1* 1897. *.* The receipts from the rent of the cold rooms in the City Stores reached 46.472 crowns by the 1910 collection. Maker of the Machinery: Pražská akciová strojírna drive Ruston. Two refrigerators absorbing 50,000 calories per hour. Cost of con- struction about 160,000 Crowns. -- 518 The refrigerating installations of the city of * - - Prague. } By Louis Čižek, Chief City Engineer (Prague). The refrigerating installation in the Central Abattoir (tistredni jatki) of Prague. (In operation since the lst of Juli 1895). For the needs of the meat market (64.8 metres by 28.5 metres in size), a refrigerating plant has been installed at the central abottoirs of the City of Prague, for meat intended to be sold in Summer, or for meat returning from the market. A refrigerating installation is then required, not capable of holding all the meat in the abattoirs on the market, but only a small part of them. In accordance with this intention, the area of the installation, is only 300 square metres (cold rooms), in a building adjoining the meat market (on the east side) being 2054 × 12.65 metres in size. Af On leaving the market one comes into a cold antechamber (82)×200 metres) and from thence into a cold room divided into four compartments, one on each side 11.00 X9:02 metres, one in the middle 7:20 metres by 9.60 metres, and a smaller one 8.2 × 2.6 metres. The walls of the cold room are 95 centimetres in thickness, with insulating space and having double windows hermetically sealed, furnished with glass, 6 millimetres thick. The height is 3:00 to 325 metres. The ceiling is vaulted and made of hollow tiles and supported by cast iron columns; the floor is of cement 10 centimetres thick, the walls are covered with cement to a height of 2 metres from the ground. To prevent the cold escaping, the cold room is insulated under the floor by a layer of . cinders one metre in depth. - To hang up the meat, iron hooks, more than 800 in number, are fixed on the cast iron columns. The cooling of the air. On the first storey above the central part of the cold rooms, there is a place 7.2 × 8.2 metres by 2.70 metres high, containing two systems of ironpipes, which serve to carry the refrigerating liquid. (calcium chloride) 519 Each apparatus consists of 80 pipes, each 5 metres long, and commu- nicating with each other, for the whole height of the room. - By means of partitions of impregnated wood the space is devided in such a way that the air, brought in to be cooled would pass between the pipes of the refrigerator from the top down and would pass out through openings in the floor into the central part of the room to be cooled, cooling this, and thence passing into the side compartments. The wooden air conduits placed in the left above the sides of the coold room, serve for the circulation of the air. The warmer air ascends. . trough 12 openings in the ceiling, each one of which is 300 millimetres in diameter, to be collected again into two air conduits each one being 800 by 800 millimetres, and thence it ascends by four transversal conduits 600 × 600 millimetres until it enters the places which contain the appa- ratus cooling the air, sending it straight under the ceiling whence it descends again, passing through the refrigerators, into the cold room. For renewing the air, ventilating pipes of galvanised iron are provided firstly, 400 to 500 millimetres in diameter, then openings at the bottom of the building 200 millimetres in diameter, and placed at a height of 200 millimetres above the ground. An electric ventilator 500 millimetres in dia- meter, circulates the air through the conduits by means of valves provided in the interior of the latter, which regulate the drawing in of the fresh air, and the expelling of the used air. The normal temperature of the cold room in Summer is + 29 C to + 40 C. The salt water (a solution of calcium chloride) is cooled by means of a refrigerating plant in a special building, in an engine room 20 metres long, 8.8 metres wide by 99 metres high, constructed on the Linde System, which as is known, makes use of the capacity of ammonia of diminishing the surrounding temperature, by passing from the liquid to the gaseous state. The liquid ammonia necessary for this operation is contained in coils immersed in brine an evaporating vessel of galvanised iron, provided with an insulating covering consisting of sheets of cork and oak boards. There are two of these vessels in the form of vertical cylinders, one small and the other larger, and they contain a cold solution of chloride of calcium due to the continued evaporation of the ammonia. The total effect of these refrigerators is 30,000 Calories per hour. The ammonia gas is liquefied afresh by compression and cooling. The compressors serve to compress this gas, and the condensers serve to con- dense the compressed gas. There are two compressors resembling horizontal steam engines. They are driven by a 60 horsepower steam engine, at the left near the entrance to the engine room, provided with a Callmann destribution system, having a cylinder 375 millimetres diameter by 700 millimetres stroke. This steam engine, working at 82 revolutions per minute, drives one of the compressors direct and the other, installed in the basement, by transmission. 520 Besides these, there is a dynamo serving for the production of elec- trical energy for the lighting of the cold rooms, the engine rooms, and boiler rooms. - There is also a reserve steam engine of 40 horse power, 100 revo- lutions per minute, 7 atm. pressure; and there, is a high speed engine of 15 horsepower for driving a dynamo supplying 150 incandescent lights, lastly an injector fixed on the wall of the engine room, for injecting water into the boilers. The compressors compress the ammonia gas, sending it to the con- densers, that is to say to spiral tubes placed in two vessels like those of the refrigerator. The vessels of the condensers are filled with water from the mains, or from wells, or carried from the river by an aqueduct. The liquid ammonia passes by means of a special valve, from the condenser to the refrigerator, when the process, described above begins Over again. In order to obtain an even temperature through all the contents of the vessels of the refrigerators and condenser, a rotating stirrer is placed on the vertical axis of each vessel, and driven from the main transmission shaft, by means of lateral connections (belts und toothed wheels). In 1906 the vessels, or submerged condensers, were replaced by a sur- face condenser, which gives better condensation, with a smaller consumption k=- of cold water. It has already been mentioned that the low temperature of the cold rooms is obtained by means of a refrigerating solution of chloride of calcium circulating in the pipes. Constant circulation is kept up by a small pump which is fixed near the refrigerators, and which first draws up the cold salt solution in the bottom of the vessel, and then drives the solution which it has drawn up through a series of well insulated iron pipes placed in a special passage from the engine room to the cold room, where part of the cold is commu- nicated to the air, and the solution is thence taken back to the engine room, so that the warmer solution re-enters the refrigerating vessel to be cooled Över again. - The steam required for running the engines comes from the boiler room common to the whole of the abattoirs, especially to the pork scalding house. w- In this room are installed three boilers on the Tischbein system, each having 200 square metres heating surface, and supplying steam at 7 at- mospheres working pressure. - The heating of the boilers is on the Cario system, with a brick chim- ney of masonry 45 metres high and 1.45 metres in diameter. 6; All the machinery was supplied by te Premier Machinery Works (I. Českomoravská strojísna) of Prague, at a price of 250,000 Crowns, in combination with the firm of F. Ringhoffer of Prague-Smichov, which spe 521 cially installed the refrigerating machinery, and the rest of the cold storage plant. Although during the fifteen years that this plant has been installed in the Prague Abattoirs, it has given entire satisfaction, the need must be - recognised, nevertheless, of larger cold storage space. It is to remedy this that the administrative council of abattoirs has just decided that a sum of 600,000 Crowns should be provided in the next years (1911) budget, for the construction of a large new cold storage installation in the Central Abattoirs of Prague. II, the Installation of Cold Storage in the "Stores of the Old Towns (Staroměstská trznice) in Prague. (Working since March 1st 1897). The entire basement of the stores includes more than 2000 square metres of cellars, of which 526 square metres are fitted up as cold rooms. With a height of 300 metres, the space of the cold rooms measures 1578 cubic metres. § --- This space is divided into 5 rooms, according to the provisions to be stored, in order that each compartement may be kept at any desired temperature. The compartements are from 80 to 122 square metres in area, and divided by means of iron partitions into 81 cells or boxes, reserved for the merchant butchers, etc., and are provided with suitable passages. The floor is of asphalte on a concrete foundation. The cooling apparatus and the pipes, as well as the necessary steam engines and boillers were provided by the Prague Engine Company (late Ruston Works) at a total cost of 160,000 Crowns. The engine room (10:15 x 8.6 metres, or 87.29 square metres in area) is situated in the basement of the south-east part of the stores, where are also the boilers for the engines, which drive the dynamos for lighting the stores by electricity. The two refrigerating plants installed on the Riedinger carbonic oxide system, consist, as is well known, of three parts, a refrigerator, a compressor and a condenser. The power of each compressor is reckoned at 50,000 fri- gories at – 59 centigrade. The liquid carbonic oxide contained by the iron pipes of the refrigerator, is evaporated, sucked in, and compressed by the compressors. The carbonic Oxide gas, after being compressed, is liquefied in the con- denser by water drawn from a well, which was constructed near the engine room and which cost as much as 3000 crowns. The cold, obtained by the evaporation of the carbonic oxide, is communiated in the refrigerator to the solution chloride of calcium (brine) at about 5° below zero C, which is pumped through the pipes by means of two rotary pumps, and thus carried to the cold rooms. 522 The cooling of the air is effected directly by a system of pipes con- taining brine cooled in the refrigerators. Four of the five compartements of the cold store are provided with small antechambers, serving to cool the air in front of the room. - An electric ventilatorserves to circulate the air in the cold rooms. While - the air passes across the refrigerating pipes through which circulates, the cold solution of chloride of calcium, it is cooled and gives up the moisture which it has just taken up, and which deposits itself in the form of frost on the pipes. To prevent the frost accumulating enough to hinder the cold from beeing communicated to the air, it is arranged for the brine pumps to stop from time, to time, to obtain a warmer temperature so that frost melts and leaves the iron pipes bare. ** Two ventilators are provided for the renewal of the air, one of which draws the air, already tainted in the cold rooms, outside; while the other draws in pure air and drives it into the outside cases where it is cooled by the pipes of salt water (brine) before entering the cold rooms. Two horizontal steam engines are provided to drive the compressors; they develop 36 horse power each at a speed of 60 revolutions per minute and at a pressure of 9 atmospheres. A. The steam required for driving all the machinery is provided by two boilers on the Rautenkranz system each having 100 square metres of heating surface, and steaming at a working pressure of 9 atmospheres; they are provided with the usual fittings. These boilers furnish at the same time the steam for driving the electric lighting plants (dynamos) of the stores. (Two horizontal steam engines of 20 horse power each, drive two dynomos each of 12,500 Watts output). A chimney of masonry, 35 metres high and 85 centimetres in diameter serves to carry off the gases from the boiler fires. *--- 523 The Feeding of the Nations.”) Report given by Mr. A. de Wendrich, Vice-President of the International Association of * ~ Refrigeration. In his interesting essay on,The European Market for Perishable Products," Mr. Richard Bloch calls the attention of the nations to the markets where the demands are more active, and to the countries that contribute most to the supplies of the former. f w These statistics relying on the documents published by the different Administrations of the customs do not allow forming a true notion of the export and import of each country, and are destitute of the necessary refe- rences to the feeding of the nations, the importance of which appears evident from the following specification: 1. The international commerce in perishable products (total of tonnage and lines). 2. The distances travelled by these products in the national and international commerce (wagons full of merchandise and empty). 3. The business transacted by the different lines (land, river and sea) ser- ving the same markets of production and consumption in the national and international commerce. 4. The forwarding-charges (tariff) per ton-kilometre. 5. The influence of syndicates and trusts on the transportation of these goods. 6. The amounts carried by the transportation companies and their record. 7. The quantities of rollingstack used in this kind of transportation and the distances covered. 8. The time spent by each vehicle. 9. The net speed (in kilometres per hour of each vehicle, including stoppages). 10. The use of special") vehicles with convertible axles, necessitated by differences in gange. -- Considering the desiderata expressed by the International Congress of Railways held in Berne 1910 particularly oth at the running of refrige- rated cars would be more advant age ously secured by private *) Supplement to ,St at is tics of Refriger a ted Transportation, report given by Mr. Wendrich, Vienna 1910. - 1) Tubular cars on 2 bogies, provided with ventilating apparatus, system Farcot, for the - transportation of fresh meat. Weight of the load: 35000 kilogrammes. Tare: 18980 kilo- grammes. Type: Belgian State. Other types admitted in different countries. Reduction of 80%. Charges made for repairs, compared to ordinary cars. Charges based upon capacity of load per ton inferior by 20 to 30°/o to those of ordinary cars. Jointstock Company of Tubular Cars. Avenue Louise 62, Brussels. 524 companies", it would be necessary to get special information, as antici- pated in the project of the Statistics of Refrigerated Transpor- tation.) Such information is indispensable in order to introduce into the common tariffs of the different countries any facilities compatible with this transportation in refrigerated wagons and ice rooms on steamers in the national and international commerce. In view of the importance of the commerce in perishable products, e. g. in America and Russia, by the considerable number of wagons and the great length of distances superior on an average to 7000 kilometres, a rational use of all means of transportation could be obtained by these statistics,”) and so it would be possible in advance to prepare the ground for the activity of those private companies by the establishment of uniform rules and such regulations as would be favorable to the in ternational circulation of these wagons. The 1st International Congress of Administrative Scien- ces at Brussels 1910 found it urgent”) to organize, amidst the permanent commission of the International Congress of Administrative Sciences, a Com- mittee on the Means of Transportation, in order to form a connecting link between the men of science and the administrators who are specially engaged in these questions concerning both, the running of the rolling-stock and the use of the means of transportation; moreover, to obtain the uni- fication of the legislation and the scientific methods along with the unifor- mity of the statistical records, based on the methotical use of journey form s etc.; in short, to secure, by the clever management of the rolling-stock supported by special documentary evidence, a rational use of all the means of transportation and an advantage o us circulation of the capital invested in these in dustries and the in ternational (private) transportation companies. We have reason to hope that this Committee at Brussels will facili- tate the work of the Statistical Committee of the International Refrige- ration Association in Paris contributing to its principal object, which is to propose improvements in the existing rules and regulations relating to the inter- national commerce in perishable products for the feeding of the nations. 1) Report given by Mr. A. de Wendrich at the International Congress of Refrigeration in Vienna, 1910. 2) Report of the Commission on Transportation, 21st July 1910 in Paris, by Mr. Bloch. 8) After the reports published by Mr. A. de Wendrich, first offfcial delegate from the Russian Empire: 1. Regulation s for the pro vision in g of the army in time of w ar. Military and commercial operations. 2. C om m i t t e e o n the me a ns of Transport a ti on. Methodical journey forms. Statistical control of the circulation of the vehicles and the returns of the comunication lines. 525 The application of refrigeration in breweries. By M. Karcher, Brewery-proprietor, Paris. The introduction of refrigeration in the Brewery Industry dates back to the beginning of last Century, at which time the Brewers were content to use cool water for governing and moderating the fermentation which took place from the top only, they having observed that the beer which was brewed in the winter season when the surrounding air was cold, was always better than that made in the warm season. This was the starting point for experiments with ice, and some Austrian brewers, who commenced to use it practically, could congratulate themselves in obtaining conclusive results; its usage then spread rapidly throughout Austria, Germany, Switzerland, and in course to Elsace-Lorraine and to France. The first means of using it was by placing it in floats in the fermen- ting vessels, and later the ice was placed in storage cellars to lower their temperature. It is about in 1820, that the construction of cellars with ice boxes begins, these being placed as nearly as possible in the centre of the places to be cooled, and filled with ice in winter. The important breweries adopted also the system of filling up all the empty spaces in the cellars with ice, carefully pilcd up, and cut into steps leading to the tops of the wats, so that the progress of the subsequent fer- mentation could be followed. It was not until the time that the vats were to be emptied to deliver the beer to consumers, that ice was used in the floats placed in the fer- menting vessels. The manufacture of beer was so much improved by the use of ice, that it became indespensable to brewers who made any preten- tion to good products, also, those located in regions less northerly than Germany, unable to get ice regularly in temperate winters, when it could not be harvested, imported it from Norway or countries where it was per- manently found. But owing to the cost of transportation the Brewers were faced with the impossibility of working profitably; hence certain manufacturers applied themselves to the study of machines for the production of cold and ice artificially. 526 M. Charles Tellier was one of the first who devoted himself to this, and who foresaw the use of the refrigerating machine in breweries, and from 1860 he visited the Brewers generally to enable them to procure the guaran- tees of refrigerating installations against irregularities in temperature, and of ensuring the product. * The first machines installed in French Breweries were in Marseille; M. Eugene Velten adopted the system of Methyl Chloride, while M. Godfried Veten chose the Ether machine. These two breweries in the South of France had never had ice at their disposal, which explains that the first installations of refrigerating ma- chines, beginning in 1864, were in a district where the consumption of beer was of relatively small importance, compared to the east of France and Germany. - * *g. A few years later, about 1875, the ice machine commenced gradually to take the place of natural ice, which to-day is almost entirely abandoned, and only resorted to in emergency. At this time the Galland brewery in Maxeville installed a Raoul Pictet Compressor, which was specially intended to make blocks to place in the floats in the fermenting vessels; other in- stallations followed, and the ice machine was adopted by the brewery. The breweries then thought of using cold without the freezing of water, and it was again at the breweries in Marseille, M. M. Veten, who were the first to use Coils in their vessels and vats, in order to moderate the fermentation, and lower the temperature. We think it was the Director of the Société Genevoise, of Caire, for the artificial production of cold, who in 1877, made the first installation of Brine circulation in coils placed in the ceiling of cellars for the purpose of cooling them, without probably thinking, at that time, how general this application would become; it is now the most extended system of refri- gerating. - It is however to-day outdistanced by the use of direct expansion, which we think will come more and more into general use. This is, in our opinion, an important advance, because besides drying the rooms by absorbing the moisture in the air, it does away with an in- termediate agent, and thus allows a more profitable use of the apparatus, and maintaining the rooms at very low temperature. The first application of direct expansion in cellars was made in Bel- gium, at the initiative of M. Lebrun, manufacturer in Nimy, who has even extended this system of refrigeration to beer leaving the vessels. The re- sults which I have seen, have always been very satisfactory. w The installation of direct expansion implies a perfect construction of the apparatus, which should be very carefully made to avoid the escape of ammonia, in the cold rooms, which may be more than unpleasant. Up to the present time I know no one accident in connection with the pipe batteries, which are always very carefully tested before being erected. 527 • *. - . The evaporation machines have been abandoned on account of the - irregularity of their working, and on the other hand compression machines have come into general use. * The most extensively used is the Linde Ammonia Machine, which is seen almost everywhere, especially in Germany. The Carbonic Acid machines, have not, up to the present, attained the development that was expected. The Raoul Pictet sulphurous acid machines are found frequently in France, Switzerland and in the Colonies. The quality of all these machines depends always upon their very careful construction. - - For some years not a few brewers, have made use of refrigeration for the storage of hops. The best results have been obtained, and the hops are preserved in a state of perfect freshness without losing, so to speak, any of their precious qualities for the manufacture of beer. - Summing up, it may be said, that, apart from the raw materials, cold is the most important factor to the brewer, for it is indispensable in the manufacture, and for the preservation, of his products. It is by its means only that he is enabled to regulate and direct the whole process, and retain the carbonic acid produced by fermentation in solution in the beer, which is so essential to the composition of a good beer. - 528 The Preservation of Hops after Removal from Cold Storage. By M. A. Mertus, Engineer, Professor of L'Ecole Superieure de Brasserie“ at the Univer- sity of Louvain. .* The best means of preserving hops consists in storing them in bales, slightly compressed, in rooms where the temperature is kept constant bet- ween 0° and 3° C., and where the perfectly dry air is frequently renewed. The changes which take place in hops are due to direct oxidation by the air, the development of certain microorganisms, and to moisture. It has been recommended not to air the refrigerator for fear of acce- lerating oxidation and losing the essential oils. This fear appears the more justifiable because the loss of the essential oils, besides depriving the hops of some of their qualities, exposes the soft resinous substances to very rapid deterioration. Nevertheless, we consider, that under the actual conditions of storage, the danger of excessive aeration is hardly to be feared at all. Without doubt, compression of the hops, and the canvas sacks which pro- tect them, prevent oxidation and losses from having any effect on the mass of the merchandise. Under these conditions we believe in freely airing, in order to keep the air in the refrigerators pure and dry, and hence to prevent the ravages of microorganisms and moisture. Our opinions are based upon comparative examinations of a large number of specimens. As a rule hops are in a much better state of preservation when they come from well ventilated refrigera- tors; and when different samples from one refrigerator are examined, it is not infrequently found that there is a difference in the amount of alteration in those parts where the main air current passes, and in corners where the renewal of the air is insufficient. However this may be, differences in the amount of aeration do not appear to have any appreciable effect on the quality of the product pre- served, because almost all refrigerators afford hops whose appearance from a commercial point of view, and whose intrinsic qualities, are very satisfactory. Without doubt fresh hops may easily be distinguished from preserved hops, 529 but it is almost impossible to classify different samples according to the time they have been preserved. Moreover, numerous researches have shown that preservation by cold considerably retards certain changes of a chemical nature, which progress with the age of the hops. One of the most characteristic of these changes is the transformation of soft resins into hard resins; note (the oft cited figures of Briant and Meacham bearing upon this subject. Preservation of hops by cold gives excellent results when they may be used immediately on leaving the refrigerators. In Belgium this mode of procedure is often impossible. * The large majority of our breweries only manufacture beer fermented upward, they do not employ refrigerating machines, and it is the dealer in hops who undertakes to carry them in refrigerators. s They are generally stored in Bales weighing 150 kilogrammes ; but the average monthly consumption of hops in our breweries making upper fermented beer, hardly ever exceeds 100 kilogrammes, and it is moreover a common practice to use several kinds of hops at the same time. The result is that, after leaving the refrigerator, the goods remain exposed in the brewery sometimes for a very long time. Therefore it would not be without interest to examine how the hops keep after leaving the refrigerators. In order to solve this question, we have examined several kinds of hops from different sources, preserved in a refrigerator for a period varying from 10 to 22 months. We took several samples weighing 10 grammes each, of each kind, which we exposed in thin layers on the floor of a granary where the temperature throughout the test varied from 21 to 170 C. One of the samples was boiled from time to time, for one hour, with brewing wort in the proportion of 4 grammes per litre. The wort removed from the hops was then divided among six sterilized flasks, open to the atmosphere and kept at 24° C. in a stove. The time which elapsed between when the wort was placed in the stove and when it gave the first external signs of alteration was observed for measuring the antiseptic power of the hops. For each sample we took the average of six tests; irreconcilable results were eventually eliminated from the series. The absolute value of the antiseptic power varied from one sample of hops to another; but the direction of the curve giving antiseptic power as a function of the period of keeping, after leaving the refrigerator, re- mained fairly constant under the conditions of our tests (See diagram). We observed a rapid fall during the first days; in a month the antiseptic power had fallen at least by 30% of its original value. This result does not prove that the value of hops diminishes by 30% in a month, but at least it shows that certain of its qualities undergo rapid alteration. 34 530 This fact, which is not an uninteresting one, partly explains why it is that some brewers of highly fermented beer place but so little value on preservation in refrigerators. The following conclusions may be drawn: 1. The brewer should use hops which have been preserved in a refri- gerator, as soon as possible; he should keep them under the best conditions Pouvoir Antis eptique * \ 100 S0 80 TD 50 x * 50 4:0 30 20 10 U l ! | |-Jours 10 20 30 Dupée de conservation après sortie dufrigoriſere. for preservation, that is to say, in a cool dry and preferably in a dark place. 2. Hops intended for medium and small sized breweries making highly fermented beer, should be kept in cold storage in bags of 50 kilogrammes at most; and should be taken out only as they are required to be used by the brewer. 531 Refrigerating by Ventilation for Ferment Cellars and the Application of this System to Other Cooled Rooms in Breweries. By Ingenieur Rudolf Planckh (in Brüder Reininghaus Brauerei A.-G.), Graz-Eggenberg. The cooling machine industry has gained undreamt of importance and completion through the introduction of cold plants in breweries, and this also helps other branches of industry. On the other hand the creation of cold plants makes breweries independent of outside weather influences, and to-day, one can no longer imagine a large brewery without a cooling machine. The introduction of the cooling machine came about gradually. First Some large breweries introduced fresh-water cooling for wort-vat cooling and fermenting-vat cooling. Then followed the artificial cooling of cellars. The cooling of rooms was almost exclusively effected by a network of cooling-tubes on the ceiling. The advantage of this arrangement as com- pared with ice-cellar cooling was enormous and gave the greatest satis- faction. These installations exist even to-day, and even new brewery plants are still frequently conducted on this system. Besides brewery cooling machines, cooling plants for slaughter-houses became continuously more frequent. There however not only a suitable coo- ling of the rooms but also a great replacement of air was effected. This requirement is best met by the air cooling apparatus with mechanical ven- tilation, which is at present in general use in slaughter-house plants. As a plentiful air replacement is also required in the ferment cellars of brewe- ries, it was natural that this system should be introduced here too. The manner of working of ferment cellar ventilation arrangements consists in the suction of large quantities of the air from the ferment-cellar, by means of a ventilator which also presses it through a specially construc- ted air cooling apparatus. Thus the air is cooled, deposits a portion of its moisture on the cooling system, and, thus cooled and dried, is blown back again into the ferment-cellar, where it absorbs more warmth and moisture. 34% 532 Simultaneously a small quantity of fresh air is sucked continuously in and, after being also cooled and dried in the air-cooler, conducted to the ferment cellar. This additional fresh air presses down an equal quantity of air containing carbonic acid on to the lowest parts of the ferment cellar, and this air passes off through suitable Small conduits. The air coo- ling apparatus is frequently provided with a heating apparatus which makes it possible to work the air-cooler, for the sake of drying the air, even in cold seasons, without changing the cellar temperature. * We distinguish two kinds of such ventilation arrangements. In one, the mixed system, the greater part of the cooling pipes are placed in the cellar itself, in the manner usually followed, and the rest are arranged in the special pre-cooler. The quantity of air circulating, and the size of the ventilator and of the air conduits need only accord with the number in tubes lying in the pre-cooler. With well isolated, dry cellars the condition of the air then completely suffices for the customary general requirements. If, however, the particular cellars are damp, and inclined to form mould on the walls and vats, or if in normal cellars great importance is attached to the air being as dry as possible and to the absolute avoidance of the harm- ful dripping from the cooling pipes in thawing in the cellar, the whole cool piping is arranged in the air-cooler and the whole of the cold neces- sary for the ferment cellars is carried by the circulating air. The ventilator and air conduits will, here be of natural size, yet the condition of the air in the ferment cellars satisfies the highest requirements. The arrangement of the air conduits and of the air-cooler is naturally entirely dependent upon local conditions. As a rule the cold air is con- ducted into the lower part of the cellar and the warmed air sucked out from the upper part. This plan has the advantage that the direction of movement of the air blown in agrees with the natural air circulation and is accordingly supported thereby. In many breweries, however, where the ferment cellars are high enough, both feed and suction pipes have been arranged on the ceiling with Success. In such case one must avoid blowing in large quantities of cold air directly over the vats, to avoid an unfavourable influence on the fermentation, yet, on the other hand, the cold air must not be blown directly against the ceiling, that this may not be too greatly cooled, which might lead to deposits on it. The air-cooler ventilator is generally driven by an electric motor, and it is useful to arrange this for a variable number of revolutions, so that the air delivery may be regulated according to the requirements. With warm outside air the pre-cooled air should enter the cellar al- ways at a temperature of Some degrees lower than that of the cellar itself. So soon as the outside temperature is lower than that desired in the cellar, large quantities of fresh air can be let in and the air-cooler can be stopped. — Cold and damp outside air can be dried by heating and brought to the desired temperature. 533 The removing of carbonic acid offers no difficulty for cellars situated above the ground; it is only necessary to make Small openings on the ground level. In subterranean cellars the carbonic acid is sucked off, now and again, by a small exhauster, when care is taken that the fresh air pumped in as replacement, passes the air-cooler before entering the cellar. Thus all doors and openings must be kept closed. It is to be recommended that such exhaustion be effected, especially after a long pause in the venti- lation process, because during the normal working no very considerable separation of carbonic acid on the cellar floor will take place, unless one intentionally places the openings for the entrance of the circulating air fairly high above the floor, in order that the carbonic acid may not be raised by the air blown in. The thawing of the rib pipes of an air-cooler fed with salt water results from the simple stopping of the Salt water circulator, when the ven- tilator is allowed to continue working, and it should be effected as soon as the snow deposit reaches a thickness of from 3 to 5 mm. After the lapse of from one to two weeks the spaces between the ribs are often quite filled up with snow and ice, when the cooling effect almost enti- rely ceases.’ In coolers with direct ammonia evaporation thawing is generally effec- ted by reversing the ammonia current, which is comparatively quickly effected. The ice pieces that then fall and collect on the floor of the air- cooler must, naturally, be removed. To avoid this work the air-cooler may simply be shut off by closing the liquid and suction conduits, when the deposited frost is slowly thawed from outside by the circulating air and no pieces fall off. By the thawing the fungus germs held fast, during working, on to the pipes by the snow deposit, are removed by the thaw water, or the pieces of ice, and thus new quantities of impurities are continually removed from the circulating air of the ferment cellar. The heating apparatus should not, as a rule, be employed to thaw the pipes, because in this way an unne- .cessary loss of cold takes place. The ferment cellar ventilation cooling plant of the Brauerei Brüder Reininghaus, Aktiengesellschaft for brewery and spiritus industry at Graz, Imay be taken as an example of a perfect apparatus. As the ferment cellar of this largest of breweries in the Alpine lands is fitted very well and with absolutely modern arrangements throughout, it shall be shortly des- cribed, before considering in detail the ventilation cooling plant proper. The boiling hot wort passes from the boiling house first into the hop- back (see Fig. 3) situated in a special attic room (at the same height as the cold water reservoirs [1]). The wort leaves the hop-back, in order that, after cooling in the pre-cooler (4) of the cooler equivalent plant, it be taken up by the two settling vats. 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On the same floor (Fig. 3) are also found the air cooling - apparatus and the air filter (25) for fresh air for the ferment cellar, as also the pre-filter and germ filter (15) of the cooler equivalent plant, and the lift machine of the goods and passenger lift, and some rooms for the per- sonal. On the floor below (II" Story) are the beer irrigating cooling appa- ratus (7) arranged for spring and salt-water cooling. Further the tool-room, the pure yeast production room, the dull room with press (12, 13) and the filter-cloth washing machine (14). On the first floor there are 8 preparing vats (Fig. 4) besides some additional rooms, e.g. for vat store press (17, 18). Finally, in the Parterre, is the ferment cellar, consisting of 3 divisions each with 4 rows of 5, oaken vats and a total content of 200 hl. Next to Heizapparat. tº SSSSSSSSS:SSS SSSSSSSSSSSSSSSSSSSSSSSSºzºWSSSSSSSS SSSSSSSSSSSSSSSSSSS - 5 : º Luftköhlapparat aus Rippenrohren. | - T#Tº iº - 3 ; Vº HE- § § - E i is ###### Sººns # ; R& - - ; º § 5 ~. § rºle ºr § Y222. . on % º :::::::::::::::: ...Y - | § E § ########: apparat § %. c §§ tº - - - - S. ; : ; Ś | §. i–5–1 § - 9. S. l g :*:::::: sºi -º/22. Frischlum .. - etzapp. * Flſºjº-º-º: WR º * 5. * º ------- - *:: Tºš-ši. }: A- ſº * .3 - -------|-> y % Frischluft. 2: i - - - Elektro. Fºlotor % - - - - Zz.2% 2. ——º- % - Luft - 24 Frischluft —; Filter à .* / º 2.3% F 19. 7. this is another cellar with 18 ferro-concrete vats Blakolit lined of 200 hl. - total content, and further some old cellars with 30 hl. vats. The large wooden vats of 200 hl. capacity are from time to time taken from the cellar and paraffined. To this end they are taken out by means of blocks .. and pulleys and travellers, which hang over the centres of the vats on traverses. In this work special consideration must be given to the placing of ventilators, piping and lighting arrangements. . . . - The cooling in the tool-room and pure yeast production is effected in the old customary manner by means of a network of cooling tubes. There is nothing particular to be said regarding the wort cooling by means of irrigation cooling apparatuses, even though the fresh-water cooling plant, * 539 as such, differ. from the normal arrangement and is considerably more com- plete in comparison to it. - The preparing vat room and the ferment cellar proper are cooled by means of an air cooling apparatus with mechanical ventilation according to the mixed system. Most apparatuses, especially of smaller plants, possess but one tube battery and the cooling has to be stopped from time to time for the purpose of thawing the battery. This must be looked upon as an evil. In the air cooling apparatus of the Reininghaus brewery this evil is avoided by the tube battery being divided into two batteries, one over the other, each with a ventilator, which may be worked together or separately. When one battery is being thawed the other remains working with incre- ased ventilator effect. In order to quicken the thawing in cold seasons a steam heating apparatus is added. :* The fresh outside air, which is continuously sucked in during normal working through the ventilator, goes through a cleaning process by means of a dust filter before it enters the cooler. A considerable advantage is further achieved by the addition of a Linde rotation cooler behind each ventilation battery, an apparatus which has, hitherto, only been employed in slaughter-houses. In a sheet-iron vessel, through which cold brine flows, a large number of loose tin plates of 11/2 m. diameter rotate on a common axle. These plates which have a very large total surface dip into the brine up to the axle and by the slow rotation become entirely wet. The air which now flows between the greatly cooled plates is simultaneously cooled and dried, the moisture being deposited on the plates. At the same time a great portion of the germs and microcosms in the moisture of the air are also deposited, which means a thorough purifying of the air. By the close adhesion of the brine to the plates, moreover, a carrying off of the brine by the air is entirely avoided, which forms a great advantage of this apparatus. The two tube batteries and the rotation cooler can all work together, or each be separately shut off according to the desired cooling effect. The conducting of air into the preparation vat room is effected by blowing in cooled air through a side wooden pipe on the ceiling and suc- tion of the warmed air through a similar pipe on the ceiling at the op- posite side of the room. Each wooden pipe has a number of openings fitted with slides for the regulation of the quantity of air. This very simply arranged ventilation suffices completely in this room, because the develop- ment of carbonic acid is slight, and a horizontally moving air draught over the upper surface of the wort not yet fermenting cannot cause any ill effect. In the ferment cellars themselves the cool air feeding greatly differs from the method previously described, and it meets the requirements of the fermenting to an especial degree. The cooled air enters through Symmetrically arranged piping through regulating openings over each vat. After flowing round the vats it is sucked off below each wat. The mouths 540 rising about *l, m. above the floor are of concrete and lead into a system of concrete canals, built under the floor of the ferment cellar. These water- tight canals are made slanting for easy cleaning. Each mouth has a sieve top and can be closed with a tin hood when the vats are being washed. By this arrangement of air feeding the cold air entering at the ceiling through th wooden pipes sinks according to its specific gravity, Surrounds and cools the vats and is then sucked off below. As the off suction is some- what high above the floor level oportunity is afforded for the carbonic acid to settle for the most part on the floor. The carbonic acid, or the air rich in carbonic acid, is continually allowed to flow into the open through little sliding doors just above the floor level. While in former plants a strong air current was generally only attained at the ceiling, in the ferment cellars of the Reininghaus Brewery there is an absolutely even air circulation through the whole room, from cellar to floor. If we now collect the advantages of a well executed ventilation coo- ling plant, suited to the conditions prevailing, we arrive at the following principal advantages: The air is dry and does not stagnate so that no fungus formation can set in. The wood of the vats is well preserved and a cellar clearing is not so often necessary as in cooling with a cold piping network. The ferment is favourably influenced by the pure air. The conditions of breathing are much better for the personal. The walls are dry and in this state isolate much better. - The great successes in cooling attained by means of mechanical ven- tilation arrangements deserve a far greater employment not only for ferment cellars but also for other cool rooms in breweries. A beginning has been made and, especially in the last few years, a number of such plants have been executed for Hop cool rooms. The con- ditions in this case are somewhat different — an air replacement is not requi- red, but on the contrary is avoided; on the other hand, specially dry air is necessary. These requirements are best satisfied by the Humbser patent, whose object is the drying and cooling of fresh picked hops. - The Reininghaus Brewery hop cooling plant, the largest in Austria, is worthy of mention. It is arranged with pure ventilation cooling for 800 bales of dried hops. As the hops keep very well at low tempera- tures without pressing, that is in the bales themselves, it is possible in years of good and cheap hops to procure a large store of hops. The cold required with good isolation of the rooms is exceedingly slight and necessitates about 4"/o of the effective power of the cooling plant of an ordinary brewery. Other cool rooms of breweries are also with advantage cooled with ventilation cooling; as, for instance, the filling hall and the cool room of the bottling department and the store cellar. In the filling hall, the installa- 541 tion of pure ventilation cooling obviates the necessity for the network of cooling pipes together with conduits, and thus the harmful dripping from the cool pipes during thawing is prevented. . The barrels keep clean and dry, and the ventilation plant can in severe winter months be also used for heating. Through this it is possible to bring the beer to drinking tem- perature, and, without any danger of freezing, to transport it over long distances. This process, too, has proved most advantageous in the above brewery. Similar conditions rule in the bottling cool rooms. So far as I know cooling by mechanical ventilation has not yet found entrance into the store cellars of breweries, yet it would be especially sui- table for these rooms and offer many advantages. The harmful dripping from cool piping is obviated, the barrels keep clean and fungus formation is prevented. The cellar clearing need not be done so often. The air keeps pure, because the microcosms are deposited with the moisture in the coo- ling apparatus, and removed from this during thawing. The walls become sufficiently dry for good isolating. The awkward cleaning, painting and changing of cool tubes in the cellars themselves is obviated. These tasks can be more easily and cheaply effected in the cooling apparatus room. On the entrance of cold seasons the cooling machine, even in the case of subterranean cellars, can be stopped when the outside temperature is 0° and cold fresh air can be blown into the cellar and the cooling effected in this manner. A systematic, correctly executed cooling plant of a brewery, by means of mechanical ventilation cooling, will generally prove to be very favourable, economically, also. All steamers, brine feed and back conduits, and the cool piping network, as also the most disagreeable manipulation in the making of brine solution and the production of the brine itself are obviated. Their places are supplied merely by the air cooling apparatus with direct evaporation, the thin liquid feeding piping, the suction back conduit and the very simple air pipes. The required power will probably turn out to be considerably less in most cases, for the ventilators use up but little power as compared with brine pumps, transmissions and stirring machinery. Through the adaptation of ice machines for super-heating plants it is now but a light matter to fit the separate air cooling apparatuses with direct evaporation, and thereby centralise the working. *. From the foregoing it may be seen that the cooling with mechanical ventilation installation is of great importance for all cooled rooms of bre- weries, and it is very desirable that such installations receive the deserved attention and appreciation in the brewing industry. 542 The Cooling of Water for Public Consumption. By M. Ed. Bonjean, Member of the Superior Council of Public Hygiene in France. Certain waters, slightly thermal, and notably many waters from artesian strata are valuable for public consumption in districts which do not have pure and cool water. t The mineral composition of such deep waters is sometimes unsuitable for domestic and industrial purposes, but often acceptable for human con- Sumption. They are generally pure in the bacteriological and hygienic sense of the word, that is to say not contaminated, and give great guarantee of permanent purety. - - The use of such waters in districts with artesian strata can therefore prevent infectious diseases, arising from water, where the only surface water available is subject to the most dangerous contamination (typhoid fever, cholera, dysentery etc.). Unfortunately the deep waters have usually a rela- tively high temperature for drinking which, lying often between 25 and 32°C, gives an insipid taste, not at all pleasant. - This fact results in serious inconvenience. The drinking of tepid water presents no detriment to health, but one notes, in a general way, that the public prefers to use cool water, which often is contaminated, to tepid water absolutely pure. - Hence, in settlements supplied with pure water from artesian strata at a moderate temperature, one sees the public revert by preference to impure water from wells in the settlement itself, in spite of all the publicity given to this subject. º This is a very serious matter which may react sadly on the public health. tº It seems indeed of such importance to certain hygienists, that they prefer to condemn the consumption of water from artesian wells, and to advise the settlement not to resort to this method. We think, on the contrary, that it would be of great interest to public hygiene to advise in certain cases the use of water from deep borings, in spite of all the difficulties encountered in getting the public to recognise the permanent hygienic security these waters present, and the danger always lurking in water from wells located in the midst of dwelling places. * 543 The exaggerated discredit thus cast on water from artesian wells, on -account of its temperature may be remedied by refrigerating the water and giving it a temperature of about 16° C. - - - The problem of refrigerating water for consumption, refers equally to water that has been sterilised by heat. Whatever care is taken to effect an exchange of temperature in the steam sterilising apparatus, the sterilised water leaves at a temperature higher by a few degrees than that before sterilisation. This is sufficient to discredit with the public the use of such water, and as a matter of fact, one sees for instance in barracks where water is sterilised by heat, the soldiers use all sorts of subterfuges to drink impure but cold water, rather than the pure sterilised water, which is of a somewhat higher temperature. Between the limits of 17 to 229 C. the variation of the temperature of the water is very noticeable to the taste, and it would be valuable to be able to return, the temperature to 15° C. which would give it a pleasant taste and quality. It would also have a great interest to be able economically to refri- gerate large quantities of water for public consumption, efficiently cleansed or sterilised, when the same is taken from streams, lakes etc. The surface waters are more or less subject to the influence of the atmosphere and temperature, and in summer their temperature may rise to 259 C. or more, in certain parts. For the same reason as before, the public, careless in periods of hot weather, have a tendency to abandon this purified water and to return to contaminated but cool water. Moreover, certain hygienists hold that germs grow less easily in a temperature near 159 C. than at a temperature around 259 C. This is a matter of fact. But one must not forget that water for public consumption should be pure, and that in this case the multiplication of germs of ordi- nary species is of little importance. -In respect to waters contaminated with pathogenic species, the value that refrigeration would have from a bacteriological point of view wight be discussed, for the pathogenic germs are very well preserved in cold water, because they are able to withstand the struggle for life of the saprophytic species, which develop with great activity in temperature a little higher (20 to 250 C). * *. The problem would no doubt be easy to solve if it was practicable to uniformly refrigerate the small fraction of water used for drinking, or for personal cleanliness. Unfortunately, in the distribution service of water for public consump- tion, one cannot separate the small quantity of drinking water from the large quantity used for domestic and industrial purposes, therefore, in order to refrigerate drinking water, one is obliged to uselessly refrigerate the 544 largest part of the water used for washing; when to the contrary it would be advantageous that this should not be refrigerated. This problem applies equally to the purification of water which must effect the total supply, but in this case the reasons are imperious. Evidently it would be much more simple and economical to leave to the public individually to refrigerate their drinking water in suitable appa- ratus, rather than to refrigerate the whole quantity of Water distributed publicly. This is the solution which I foresee, and the more, as each individual would be free to regulate the temperature of the water to suit his taste, that ice and apparatus, judicially installed, should be close at hand, which would allow of refrigeration under satisfactory hygienic conditions, and wit- hout the ice coming in contact with the water. However this may be, the question of the temperature of water, has assumed great importance with the plublic who demand a cool drinking Water. - The refrigeration of water for public consumption under economical and practical conditions has therefore in certain cases a real interest: public opinion will no doubt be more appreciative thereof than public health, while, however, the latter will reap the benefits indirectly. 545 Presence and future of the export of butter meat, hogs etc. from Russia to Great Britain. By Dr. L. v. Cramm, Official Delegate of the Russian Government. Notwithstanding the export figures showed remarkable quantities of foods yearly exported from Russia to the United Kingdom the amount is very small in comparison with the whole import of such goods and to the enormous quantities which Russia may be able to export. I may assure that they are two principal facts which make this ano- maly; the absence of knowledge of the Russian laws, customs, condition of trade, transport etc. of such goods, the Suspicions against correct trade of the Russian business people and the absence of up to day refrigeration systems for preserving and transporting of perishible foods. As to the enormous import to the United Kingdom which develops every year I do not want to repeat the well known statistic, according to the important work of Mr. Trouberidge Critschell > Import of refrigerated food of the United Kingdom 1880–1907.<, where we find all the necessary details and I only intend to compare some figures showing Russian part of this import. The import of butter has been in 1907 210,000 tons of which from Russia 900,000 tons, from Australia 20000 tons, New Zealand 16000 tons, Canada 2000 tons etc. The import of cheese is equal to 100,000 tons and Russia does not take any part, notwithstanding that prices for cheese advanced within the last 20 years more than twice. Eggs have been imported to the United Kingdom in 1909 about eight milliards pieces of which from Russia one milliarde. The import refrigerated fruits from Australia (Tasmania etc.) in 1907, have been about 14000 tons and nothing from Russia. The meat import from Argentinia which began in 1895 with 50 tons have been in 1909 240,000 tons, equal to over 4 millions pounds, whilst the sheep import being ten years ago 66,000 heads developped now to 2% million heads. New Zealand which has imported in 1882 only 15000 Ctw. meat showed last year 2's million Ctw. Till the present time no meat import to England from Russia has been done. 3 5 546 The import of gam and poultry has been in 1895 16000 pounds and developed in 1909 to 600,000 pounds of which from Russia of 300,000 pounds. The above mentioned figures evidently show how big the Russian ex- pcrt to the United Kingdom states at the present time, but in comparison with the whole import to Great Britain there is another large output for the future in developing the Russian export of such goods, especially every goods could be sold at a cheaper price. This latter fact could be reached if the systems of refrigeration in Russia would be enlarged. In my former paper which I have had the honour to read before this assembly yesterday, I have particularly explained the cause of the present high prices for the above named products in Russia, and this is the absence of a sufficient quantity of cold storages. Ice-cars etc. which make the goods partially spoiled before the reach the Consumers, because they have been transported sometimes thousand of miles. But we cannot use the word 'sufficients because Russia does not posses cold storages or other installations of cold etablishments besides Some few factories erected in the latest time from a private company. The only exception is butter which Russia exports from the northern part of Siberia and over 2000 ice cars are runing to the Baltic ports where from Steamers, supplied with refrigerated rooms bring the butter to the different European countries. The United Kingdom knows well enough Russian butter and eggs but we also want inaugurate Russian meat to the British market and a special congress has been lately held in St. Petersbourg for studying the methods of developing the quality and quantity of Russian cattels. and we also want to enter into competition with the other countries exporting meat to the United Kingdom, but as the use of such products is greatly advancing for the reason of the cheapness in comparison with fresh killed meat, I think and I hope, we have no necessity of telling competitions but we all could be able to sell our products on the British markets successfull enough for everybody. - The Russian Government is much interested in bringing the refrigera- tion question to a modern stand, which may not only enlarge our export but first of all serve enormous sums to ourselves and therefore make the products cheaper to our people too. A special cold comittee is now establi- shed in Russia under the management of the Russian ministery of trade and industry, giving full informations and every help to every body and especially to foreigners who intend to go into negociation with Russia, to establish cold storages etc., to deal and to export refrigerated goods. Russia's Domestic and Export Trade in Perishable Produce During the last Decade. By Dr. L. E. v. Cramm, Ministerial Office for Commerce and Industry, St. Petersburg. I will endeavour in the following paper to give a concise presentation of this subject. Until lately Russia paid no serious attention to the production of butter and eggs, and the breeding of poultry and pigs. The chief income was obtained from grain growing, whilst the products mentioned were treated in a very negligent manner. For the most part this abnormal fact was due to the enormous distances that such products had to be transported before arriving at the market centres; and further, to the great dearth of means of transportation, so that the products reached the consumers in unsound condition. Even in 1900 the application of cold in the preservation, production and transportation of perishable food products was hardly known during the hot time of the year. It was in 1899 that the first 50 railway cars were used for the transportation of Siberian butter, and for this product the first cold storage was erected only a few years ago at Riga, by an English firm. Apart from the butter which has found an enormous export demand during the last decade, and for which the railway companies built a large number of cars, this latent condition remained until the foundation, for the spread in Russia, of the knowledge of refrigeration was laid but two years ago in Paris by the Is International Congress of Refrigeration. The Russian Government founded a Refrigeration Committee consisting of the representatives of State, communal and county institutions among others with technical advisers from mercantile and industrial circles interested. This committee undertook the tasks of spreading knowledge of refrigeration and its application in trade and commerce among every class of the po- pulation, of collecting the literature on the subject from all lands and trans- lating it into Russian, of publishing cheap editions, of giving popular lec- tures, in short of procuring the material necessary to assist interested parties by word and deed regarding the erection of cold storage establishments for 35% 548 the production, preservation and transportation of perishable food and with regard to municipal approval and other formalities, and further enable loans to be obtained through Russian banks on such products, etc., etc. Though it cannot be denied that in the last two years only a very small part of the task mentioned was carried out by the committee, yet without doubt this institution has entirely justified its existence, and in the near future it will probably bring about great improvements among others in foreign trade. It is now possible to obtain information concerning the necessary formalities to be observed in the erection of such establishments in Russia and for organizing companies to carry on home trade or export in such products from the committee mentioned, which of course serves no private commercial ends, but is merely an organ of the government. How great need there is for the introduction of modern refrigeration into Russia is made evident by the statistics on the subject. Thus we see, for example, that eggs that have to be transported long distances arrive at their destination with scarce 40% in fit condition, while of the remaining 60°/o a part are quite useless, and part of very inferior quality. If we consider the export figures for 1909 alone when far above three milliards of eggs with a value of 60 million Rubels were exported it will be easy to form an idea of the enormous loss that is due to the insufficiency of the arrangements for preservation and transport. At the same time we also observe that the prices of these goods would be greatly reduced by the introduction of a rational method of preservation and transport, since the loss through spoiling, etc. would be decreased to an insignificant minimum. Up to the present day the large cities of Russia are provisioned with meat that has been transported alive, sometimes for thousands of miles, and here, too, we see from the following short examples what great sums are wasted. For instance one railway car contains 750 Pud, or 12,500 kg., or a maximum of 10 head of cattle, which possess on an average only about 300 Pud, equal to about 5.000 kg., available flesh. Further the animals lose considerably in weight through such long transport. The fight against epizootic is rendered far more difficult by such long transport. Finally new districts of production would be opened up far away from the centres of consumption if it were possible to transport chilled meat in cold-storage cars direct from the chill rooms of slaugther-houses to the cold storage houses of the large cities. In central and southern Russia, especially in the Crimea and Trans- caucasia, etc., there are enormous districts in which great quantities of all kinds of fruit are most cheaply grown, whose quality is equal to that of the best sorts to be found on the markets of the world. So far however there is no export in this fruit worthy of mention, indeed even in the transport from southern to northern Russia the losses through spoiling of the fruit ex- ceed the percentages given above for eggs. - 549 For the last few years Russia's poultry export has amounted to about 8 million pieces per annum, with a total value of nearly 7 million rubels. About 600,000 Pud of game are exported annually, that is, about 10 million . kilos, in value nearly 4 million rubels. The greater part of such produce is exported during winter, in frozen condition. Only in the butter export trade has much been done during the last decade, and we see that after the opening of the Siberian Magistrals, even but a small part of Northern Siberia, engaged in butter production for export, which exported 400 Pud in 1894, equal to 6.500 kg., valued at about 6,000 rubels, surpassed the figure of 4 million Pud, (70 million kg., value Over 60 million rubels) in the year 1909. Similarly the number of refrigerator cars increased from 50 in 1899 to over 2000 in 1909. We thus have evidence of how great the productivity of Russia is in perishable produce, and what enormous increase might take place with some rational Support from the Russian Government, such as has been given in the case of butter. We also see that the Russian government, in creating the cold committee before mentioned, are taking important steps to render other products besides butter (which has not yet, by a long way, attained to the maximum point of production), cheaper and more easily exportable. I therefore take this opportunity to draw the attention of those interested or those countries which have to consider the importation of the perishable products they need for their own consumption to the fact that Russia in particular would be able to supply cheap and good produce with the aid of modern refrigeration installations. - 550 Import and Export of Meat in Various Countries and the Answer to the Question: Is the Import of Frozen and Chilled meat from abroad desirable for the Netherlands? By F. B. Löhnis, Governement Inspector of Agriculture, at the Hague, and Dr. D. A. de Jong, Professor and Manager at the slaughter-house at Leyden. According to the report of the Ministry of Agriculture in 1909 the Netherlands exported agricultural products for no less a sum than two hundred and ten million Gulden, of which sum about twenty eight millions fall to the account of beef, pork and mutton. England is our principal customer, in the last years, however, Germany appears more and more as a buyer, as likewise Belgium ; every now and then France and Switzerland import meat from Holland. In 1907 the total export of beef and veal from Holland amounted to sixteen million kilos in value of nine millionGulden. Of this amount England received ten million kilos and Germany five and a half million. Fresh mutton is nearly always exported to England, the same is the case as regards fresh pork. Of the twelve million kilos of fresh mutton exported in 1907, eleven and a half million kilos were destined for English ports ; of the 24 million kilos of fresh pork 22 million went likewise to England. In the years 1907, 1908 and 1909 the total export of meat from Holland was as follows: 1907 1908 1909 K i 1 o s Fresh beef and veal 13,238.324|13,595.295 | 16,873.000 Tresh mutton . * * * 12,989.425, 14,044,785 11,581,000 Fresh pork . . . . . . 24,372.790|27,181.709|30,284,000 Fresh meat (of other kinds) 16.516 3,476 P Salt pork and bacon . o ºg 503.426| 490.660 | 1,387,000 Smoked or dried pork and - bacon * G e º e & 1,039.925 | 950.225 | 1,334,000 || | Smoked or dried meat (of other - kinds) | 131,609| 229,634 P 551 The export of meat from the Netherlands has only become of impor- tance in the last few yars. At first live cattle were sent to the place of destination; for hygienic reasons, however, the frontiers were closed against them in most countries. In 1895 England set the example, Germany follo- wed it in 1894. Both countries are now closed to all kinds of animals fat- tened for the shambles. Belgium closed its frontier against live swine from the Netherlands in the year 1895, but permits the import of live oxen, sheep and lambs under certain prescriptions ; this is likewise the case in France and Switzerland. Our export of live sheep and hogs to Belgium, France and Switzer- land was in the years 1907, 1908 and 1909 as follows: mºmºmº-ººººººº. I-ºs | 1907 | 1908 | 1909 H e a d | She ep a n d 1 a m bs: * Belgium (Belgian Statistics). . . . - 69.266 89.410 France (French Statistics) | 169 4,000 64,000 } | Hogs and sucking pigs: : Belgium (Belgian Statistics) Import prohibited France (French Statistics) . . . . . 403.763 244,000 - Switzerland (Swiss Statistics) . . . 23.223 28.820 - - The above mentioned figures are, especially as regards France, some- what remarkable, since they plainly testify to what great changes the market may be exposed in this country within a short period of time. In the years 1907 and 1908 France imported only a small number of sheep from Holland. This number rose all at Once in 1909 to 64,000 head, and this in combi- nation with a temporary lack of mutton in France and low prices of meat in England. With pork the exact opposite occurred, curiously enough. In the years and 1908 hogs fetched a remarkably high price in France, which caused an immense export from then Netherlanes as result. Breeding on a large scale in France brought down the prices rapidly and this induced other foreign countries to buy. The chief purchasers were Switzerland and Italy, but since the last months of 1909 the Netherlands too, though in 1907 and 1908 they sent large quantities of swine to France have bought about 2000 head at the market of La Villette every week. These animals were transported to Holland, slaughtered in the great export- abattoirs and then exported principally to England and Germany. Among the countries importing meat, England plays decidedly the most important part, but Germany also has for some years been no longer 552 able to satisfy the meat requirements of its own population and that is also the case in Belgium and Switzerland. In 1907 the total import of meat to England amounted to 952 million kilos, of which 306 million kilos were beef, 234 millic n kilos mutton and 372 million kilos pork. In 1908 the corresponding figures were sixteen million and two million kilos. Germany imports exclusively fresh meat and in this trade Holland takes an important part. England on the other hand makes up its deficit by the import of meat preserved in cold stores from oversea-countries. So far, however, as England imports fresh meat, Holland is its most important supplier. Among the suppliers of frozen meat the United States of Nord- America held the first position, but an alteration has occurred recently. In 1908 the export from North-American ports amounted to 310 million kilos. The Argentines exported 219 million kilos in the same year, and the British Colonies, chiefly New-Zealand and Australia, 250 million kilos. Denmark follows with 103 million kilos and then comes Holland with 45 million kilos. It is noticeable that the export of meat from the United States has been steadily on the decline since 1906, so that the export in 1909 amounted only to 57 per cent. of that in 1906. Various causes have contributed to this. In consequence of the increase of population, this question has become of growing importance for home consumption, while the stock of cattle has remained pretty much the same in the last few years. This stagnation is largely the consequence of the fact that the open pastures for the vast herds of horned cattle in the Western and Northern States are becoming less and less, because the pastures are being more and more used for agriculture. Cattlebreeding has in consequence become considerably more expensive, because the altered circumstances have made the building of stables and sheds necessary. The time no longer appears to be very distant, when the United States of North-America will play only a subordinate part as ex- porters of meat and cattle for the shambles. For the export of beef on the other hand the Argentines appear to become the greatest suppliers, while New-Zealand and Australia are the chief exporters of mutton, and will remain so most probably for the present. As regards the prices of meat, they rise and fall pretty regularly but the time is long passed when the small local market regulated the prices. Killed meat has become a commercial product of the first rank, the price of which is consequently settled in the market of the world. This refers principally to meat preserved by artificial cold; the price of fresh meat is decidedly in connection with this; but with a product of such a perishable nature local circumstances exercise a stronger influence. The Inter- national Meat-Trade is rendered more difficult by the customs and also by the severe regulations for examination on the frontiers. These measure are partly intended to protect the homebred cattle from the bringing-in of in- 553 fectious cattle diseases; on the other hānd they are intented to further the breeding of cattle in their own country by forcing up the prices. The scarcity of meat in Germany some years ago is still fresh in every one's memory. Government was at that time appealed to from all sides to promote the import of meat and cattle for the shambles, but, supported by the powerful Agrarian party Government has not complied with this wish. The result of this was, that enticed by high prices, the stock of hogs has been considerably increased by more numerous breeding in the last few years. As is well known, pork plays an important part in the food of the German population. The swine-stock is capable of a quick increase and de- crease, much more than it is the case with the stock of cattle, which repre- sents a more permanent element in the farmyard. The large increase in the amount of fathogs had produced in so far the desired result as the prices of pork declined considerably, so that at times they quoted lower in Germany than in Holland. It is doubtful whether the financial results of this extension of the cattle-stock afforded our eastern neighbours the advantages they expected. But this extension coincided with a period of high prices for fodder, while the increases of diseases among swine in Germany, which caused heavy losses to breeders gave further reason for lamentations. In France too the same variations were visible on a smaller scale as in the German meat-markets. As mentioned above there was, in spite of high prices, a great lack of pork in France in 1907 and 1908. The high figures attained there, too, caused a great development of the cattle-stock, the result of which was a considerable decline in prices, so that France became an exporter of pork in 1909. In England all illusions with regard to the meat supply of the popu- lation have long been abandoned in order to provide for the actual de- mands. A very considerable part of the meat required is drawn from abroad, and the colonies play decidedly the most important part in this trade. Up to a short time ago there was a certain dislike among a large part of the meat-buying public to meat preserved by artificial cold. As is well known there exists a difference between frozen and chilled meat. Frozen meat is brought to the market in a hard frozen state, whereas chilled meat has to be regarded as fresh meat, being kept in an atmosphere which varies at Some degrees above freezing point, and being also sterilised by modern methods. This chilled meat is practically not to be distinguished from fresh meat, which, however, cannot be said of frozen meat. There existed for a long time a prejudice against frozen meat, but owing to the methods applied in cold stores the quality has improved, while, at the same time, the Curious fact is noticeable that the taste of the English meat-eating public seems to be changing in favour of frozen meat. In 1907 England had the greatest import of frozen meat ever attained. In 1908 the import also was very considerable, the result of which was the accumulation of enormous stocks of frozen meat in English cold storages- 554. supply having been larger than demand. — According to reliable statistics, the stock in English cold storages amounted in 1909 to two million head killed sheep imported from abroad. This glutting of the market caused a consider- able fall in prices, not only of frozen but also of fresh mutton. In addition to this, the stock of sheep was greatly increased in England, in consequence of the high prices in mutton in the years 1903 and 1907 and that from 25,639,797 head in 1903 to 27,618.419 head in 1909. That this increase exer- cised its influence on the meat-market is obvious, and is very plainly shown by a report made by the Superintendent of Central-Markets in England, from which we learn that the supply of mutton and lamb produced by English breeders was no less than 75 per cent. greater than of 1908. Both factors: Larger import of meat from abroad, and considerable increase in the number of sheep at home, coincided, and therefore we need not be surprised at the decline of prices. In the tables given below such matters are explained more in details. -- Import (in tons) Number of sheep and of mutton lambs in England he a d he ad 1902 . . . . . . . . . . . . . 190,978 25,765.706 1903 . . . . . . . . . . . . 210.331 25,639,796 1904 . . . . . . . . . . . . 185.114 25,207,178 1905 . . . . . . . . . . . . 195.553 25.257.196 1906 . . . . . . . . . . . . 207,234 25,420.360 1907 . . . . . . . . . . . . 232.475 26,115.455 1908 . . . . . . . . . . . . 221.700 27,039.730 1909 . . . . . . . . . . . . 238,647 27,618.419 Even well-to-do families are more and more inclined to buy the chea- per imported frozen meat, and besides in the retail trade and in the butchers' shops much frozen and chilled meat is sold as fresh meat, which certainly must cut down the price of genuine fresh meat. This is the cause of loud complaints made by English sheep-breeders who perceive their own interests in danger through the considerable decline in prices, a decline amounting to some 30% in comparison to other years. The Dutch sheep-breeders too, who produce chiefly for the English market, feel the reduction in prices in no small degree. - In the figures mentioned below a general survey will be given as follows: In fig. 1 a survey of the variation of prices of American chilled meat (Curve B), of fresh English beef (Curve B), and of frozen South American beef (Curve C), in the London market from the years 1902 to 1909. In fig. 2 a survey of the variation of prices between fresh mutton (Curve A) and of frozen mutton (Curve B) in the London market during the years 1902 to 1909. It is plainly to be perceived from these two figures that the prices of beef and mutton have deviated very considerably in the last two years. - 555 *; $ Nº & «- * * ZŽ a 34.2 (Aixes) ar, 3 & 24 && With regard to beef, a rise in Y s * ©s $ prices is to be noted for the years ** sis: g; sº s Š g - § $ $ | S. $ 1 S S | S $ $ 1908 and 1909, in consequence of the Small import of live cattle, but prin- cipally owing to the outbreak of the foot- and mouth-diseases in Ar- gentine. The import of beef had indeed Sowewhat increased in the English markets in these years, yet the supply of fresh meat was smaller. It is remar- kable that, as is plainly visible from the accompanying graphic tables, the prices of American chilled meat were during this period, almost always high- er than those of the finest English meat. It should be mentioned here that prime Scotch meat is always quo- ted a little higher than the best English. As regards mutton it is plain from the graphic tables that in the years 1908 and 1909 the price both of fresh and frozen meat declined very consi- derably, and that in equal proportions in both cases, so that it does not fol- low, as it is frequently mentioned, that the difference in price between frozen and fresh meat is gradually becoming smaller. The brand remains pretty much the same. If a comparison is made between the meat consumed per head of the population of different countries, some remarkable differences are discoverable. It is well known that the consumption of meat among Oriental nations is very small, that indeed many millions of hu- man beings, living in the warmer zo- nes, are actual vegetarians. Various causes, religious prescriptions included, have exercised a strong influence upon this. But even among European na- tions remarkable differences occur. 556 The Englishman is regarded in the highest sense of the word as a meat- eater. The consumption of meat pro head of the population in England is reckoned at 1218 English pounds or + 55 kilos a year; but it does not require a detailed explanation that this varies largely according to social circumstances.’ Beef still plays a principal part in the English menu, but mutton and pork represent a considerable portion of it. - - According to the latest statistics the German now consumes about 53 kilos a year, against 50 kilo in 1905. The present consumption is there- fore not far behind that of England. Two-thirds of this quantity consist of pork and only one-third of beef. The consumption of mutton is of slight importance in Germany, and only amounts to two per cent. of the total con- sumption of meat. The consumption of meat in France is estimated at 80 English pounds or 36 kilos per head of the population; mutton consti- tutes a rather considerable portion of this. s The above figures can lay no claim to absolute certainty but they give a general notion of the state of things. There are no reliable figures to be had for Holland either. It can, however, be easily ascertained that mutton plays a very subordinate part in the diet of the people. *- The larger number oft he middle-class in that country shows a disincli- nation for mutton. In the country, even in a province So rich in sheep as North-Holland, the use of this kind of meat is virtually unknown; and only in large towns lamb and mutton are more in use, and that principally among the well-to-do people. It is noteworthy that the consumption of horse-flesh is spreading more and more in the different countries of Europe and in the Netherlands among the lower classes, whilst the use of this meat has remained almost un- known in England. It is a remarkable phenomenon that England, which imports enormous quantities of beef, mutton and pork, carries on a rather considerable export-trade in horses for the shambles, chiefly with Belgium and Holland. We give below a table of the meat-consumption in the Netherlands from the annual report of the abattoir at Leyden, which gives a survey of the consumption per head of the population in this district in 1908. These figures do not by any means represent the consumption of meat in the Netherlands, although they give us a certain insight into our town-popula- tion's consumption of the meat furnished by different animals. The meat-consumption at Leyden was 52.44 kilos per head and year, and may be distributed among the different kinds of meat as follows: 21.5 kilos beef, 21:16 » pork, 4:04 r > veal, 5.5 x horse-flesh, 00:16 x mutton, O'08 x goats-flesh, 557 It is plainly to be seen from this table that the consumption of beef and pork is almost equal, that the consumption of mutton constitutes only an unimportant fraction, whilst the consumption of horse flesh on the other hand is by no means slight. The figures below, as regards the meat-consumption in different towns in Holland, are taken from an unpublished report, which however, gives a sufficient guarantee for its reliability. According to this report the consumption in the years 1901 till 1905 amounted in kilos to: 1901 | 1902 | 1903 1904 || 1905 Remarks 3972.3856,3922.40214069. In Amsterdam large quan- tities of prepared meat are imported. l Amsterdam . ; Leyden . . . 52—|50.93|51-54, 51.46 55-71 Maastricht . . — 72.9 || 75'5 79.9 7845 The workmen in factories - t consume much meat. Nymegen . . 52-6 |51-2 |503 |522 313| Dortrecht . . 44-9241.9 |38.6 |37.9 |38.5 || Contains both fresh and | preserved meat. | i; Utrecht . . . . about 40 kilos per head - As a matter of course it follows that for the sake of the health of the population, the different Governments have established a strict service of inspection on their frontiers for the thorough examination of all meat brought from abroad. In certain countries, among which is Holland, the import of meat from abroad is prohibited; but in single cases it may be exempt from this prohibition. As to the regulations to which imported meat is subjected, no difference is made in the different countries of Europe, with exception of England and Germany, between fresh and frozen meat. It is in particular always prescribed, that whole and half rumps shall be imported, and that part of the intestines must still be attached to them. For frozen and chilled meat, which as a rule must be shipped from great distances, this is an annoying regulation which causes great inconvenience to the trade in this kind of meat. The following regulations are at the present moment the standard- ones in the Netherlands as regards the import of meat and cattle. 558 3 & 24 § (herº) /. P- or 3%&eigs ºro $ -， 559 The importation of beef and goats-flesh was prohibited by Royal Order of the 8th of December 1870 (Staatsblatt Nr. 194) which Order was likewise extended to pork by Royal Order of Aug. the 14th 1888 (Staats- blatt Nr. 142). Certain modifications of this prohibition may be permitted by the Minister of this department. Since then an alteration of this order has been made to the extent, that all Commissioners of the Queen have been authorized to grant exemption from this prescription in the name of the Minister. By Royal Order of June 22, 1896 (Staatsblatt Nr. 98) the import into, and transit through the Netherlands of flesh of solipeds (horses) is prohibited from countries or districts designated by the Minister of this Department. In case exemption from this prohibit is granted, it only refers. a) to meat imported in whole carcases, to which skin and lungs are still attached, and which are certificated as fit for consumption at the first Custom-House on examination by the District Veterinary Surgeon. 6) to meat for which a special permit from the Minister of Agriculture, Trade and Commerce can be presented at the first Custom-House. With regard to the importation of live animals into the Nether- lands, that of oxen, sheep and goats was prºhibited by Royal Order of Dec. 8* 1870 and this Order was extended to hogs by Royal Order of 14. August 1888. The Minister in charge was, however, authorized to modify this prohibition, if necessary. The importation, however, of cattle, sheep and goats from Belgium, of oxen and sheep for the shambles from Germany, of cattle, sheep, goats and hogs from France was permitted by Orders of the Minister of Nov. 10th 1896, Jan. 2* 1904 and Feb. 28th 1906, permanent deviations from the above mentioned regulations being granted under condition, that the necessary precautions should be taken against the bringing. in of infectious epidemics. The precautions consist of: a) Presentation of Certificates of Health. ð) Employment of Quarantine measures. The above-mentioned facts prove that strict legal measures exist in the Netherlands with regard to the importation of meat or cattle from foreign countries. The existing local regulations, likewise, concerning the admission of meat for consumption are also very strict and not easy to fulfil for meat drawn from foreign countries, whether in fresh or frozen condition. In the Netherlands a Parliamentary legislation for the inspection of food- stuffs, including meat does not exist yet and this gap is filled up by special regulations in larger districts. The result of this is, that even if a permit has been given by the Commissioner of the Queen, in the name of the Minister, for the import of a load of meat, it must be subjected to another inspection within the district for which it is destined, a matter which certainly causes difficulties. 560 Since, however, the import of meat from abroad never actually takes place, these difficulties are only of theoretical importance. 3. Germany. In Germany fresh meat may be imported within the customs-territory only in entire joints, to which various internal Organs must still be attached. Hogs must be divided into two halves, cut lengthwise. Custom-Offices have been established for the import of killed animals; and the inspection is made by Officers appointed for this purpose. The inspection is made according to the articles of the Law for Cattle and Meat- Inspection June 3" 1900, supplemented by various clauses of the Federal Council. The import-duties amount to: Mark 27.— per 100 kilos of fresh and chilled meat, » 35.— » 100 x > frozen meat, » 36.- > 100 x > bacon. In Hamburg, in the Free Trade district, the import of meat is exempt from duty; in the other part of the free port belonging to the Customs District, the same regulations are in force as in the German Empire. England. In England no import duties are paid on meat, but the importation is subject to a severe examination. This examination is made by a Medical Officer of Health according to the Articles of the Foreign Meat Regulation Act of 1908. The Officers of the Inspection Service have full power to refuse the import of meat, if it proves unfit for food; they may even order it to be destroyed. Besides high fines — up to L. 100, may be imposed for any infringement of this law. In order to give a sufficient guarantee to the Dutch dealers in meat for the valuation in foreign countries and at the same time to place trade on a firm basis, a Service of Inspection has been established for meat exported to foreign countries. According to the legal enactment of the pear 1907 for meat inspection on its leaving the port, the Government is empowered to prohibit the export of uninspected meat to any country designated by the Government. By Royal Order of May 6th 1908 such regulations are prescribed for England, so that now all meat sent to that country from Holland must have a Government Stamp affixed as a proof that it was declared sound on examination. By these measures a great service has been done to our export trade to England, and these measures are received with great sympathy and supported by the English authorities. France. In France frozen and chilled meat is subject to the same regulations and duties as fresh meat. The duties amount to: 35 francs per 100 kilos of mutton 25 x » 100 x > pork 35 x » 100 x > beef or other kinds of meat. 561 On the Conferences on the new customs-tariffs, which came into force recently in France, in the Chambers of Deputy an attempt was made to raise the existing duties. The Government, however adopted a negative attitude and consequently the import-duties remained unaltered. Belgium. In this country also, frozen and chilled meat are liable to the same regulations as fresh meat. For carcasses and halves the import duty amounts to 15 francs per 100 kilos and for meat in other forms 30 frS. Imported meat is subject to a severe examination for which purpose special Customs houses are set apart. .*.* r * *r-s- ---------> , » : --" Switzerland. The regulations governing the import of meat in Switzerland are based upon the Federal Order of January 29, 1909 concerning the inspection of imported deliveries of meat and meat-products. According to paragraph 21 of this Order, chilled or frozen meat may only be brought in with a special license of the Department for Home-Affairs. On arrival an accurate description of the kind of goods must be submitted, as well as a declaration as to the place of origin, everything exactly according to special regulations. The import duties amount to: Frs. 15 per 100 kilos of fresh veal > 10 x 100 * > * pork » 10 x 100 * > * meat of other kinds. Let us now answer the question of the Dutch Association for Refrigeration-Technique in the Netherlands: Whether it would be of general benefit to permit the import of chilled and frozen meat into the Nether- lands and what steps must be taken to promote its extension. --> - As Holland belongs to the meat-exporting countries, its standpoint with regard to the answering of this question is quite different for instance from that of England, which has to draw more than a third (35 per cent) of the meat needed by its population, from foreign countries. The same is true, although on a smaller Scale of Belgium, Germany and Switzerland, which as regards the consumption of meat, are entirely dependent on foreign countries. As regards England, mutton plays the most important part in the meat-trade with foreign countries. In 1908 the import into England amounted to no less than 9,651.418 carcasses of sheep against 1,788.159 quarters of beef. The import of mutton into the Netherlands is out of question, since, as has already been mentioned, mutton plays such a very unimportant part in the food-consumption of the population. For Holland the import of frozen beef, would only come under consideration, if it could be supplied at so low a price that its consumption might be introduced among the poorer classes of the population, for whom good fresh beef is too expensive. 36 A propos of this it may be mentioned that the consumption of horse- flesh is steadly increasing, and that it may be considered a wholesome and cheap foodstuff for the people. From the statements in Fig. 1 referring to the variation of prices both of fresh and frozen meat in England it follows, that the difference between the prices in both categories of meat amount to 1 sh. 6 d. per Stone. Supposing, the Netherlands have made the necessary arrangements to store the meat immediately on its arrival in the ports in the cold-stores, the difference in price would be almost on the same level as in England, that is + 2*/, d. = 111/, Cents per pound Avoir, or 496 Pence = 24.8 Cents per kilo. We have already discussed before, that in England frozen meat is not seldom sold as fresh meat in the retail trade. It follows from this that a a dishonest competition is thus carried on, detrimental to the interests of suppliers of fresh meat or the cattle-breeders; much in the same way as damage is done to the butter-manufacturers by the trade in margarine sold as butter. It is well known that the Dutch Government put an end to this adulteration in the butter trade by a special Act. As cheating also takes place in the same way with frozen meat it would appear necessary to enact a Law against cheating in the meat-trade, which, however, would no doubt call forth much opposition. Besides this, if the Government should admit frozen meat into the Netherlands, it would be necessary to create a special Inspection Service for this very purpose. The importation of fresh meat is virtually prohibi- ted. This may appear to be a measure of an authoritative nature, but this is not the case in reality, since the import of fresh meat would only give a chance of profit in exceptional cases. From a s an it a r y p O in to f v i e w to o the question arises whether there are no serious objections to admitting frozen meat from foreign countries. In order to have more exact information on this point our Commission has obtained an expert opinion from the Society of Managers of municipal slaughter houses in the Netherlands. The answer which we received leaves nothing to be desired in respect of clearness »From sanitary considerations, runs the answer and in the first place with an eye to the health of the Dutch people and the Dutch cattle, the import of chilled or frozen meat into the Netherlands is positively not to be ad- vised, because an inspection of this meat, with due regard to the above mentioned interests in the Netherlands is not possible, while no value can be attached to a possible inspection in foreign countries, if proper conside- ration is not paid to the conditions demanded by the Netherlands.< We have little to add to this expression of opinion of such highly competent authority. Should the Netherlands find themselves in such a position that a deficit of meat would have to be made up, then it would be time to consider how far the above mentioned difficulties could be got rid of. * 563 Very great advantages would have, however, to be apparent in order to get over these difficulties. Af G So far as it seems to us the advantages do not by any means equal the disadvantages to be expected. Therefore our Commission also comes to the con- clusion that it is not yet worth while recommending any urging of the Govern- ment to open the Dutch frontiers for the import of chilled and frozen meat. Most of the Governments of the European continent have taken up the same position; consequently it is undeniable, that with the exception of England, the different Governments have adopted anything but a friendly attitude towards the import of meat from over-sea countries. The matter has doubtless been largely determined by agrarian conside- rations, but the difficulties of a proper inspection of the meat have deci- dedly turned the scale. Since most countries have decided to create a service of strict inspection for home-killed meat, it is not to be expected that they will be satisfied with easier conditions for the import of meat from foreign countries. With the exception of Italy therefore, which permits the import of small quantities of frozen meat by way of Genoa, the continent of Europa is virtually closed to this article ; since also Sweden and Switzerland which admitted Small cargoes during the last few years-owing to the changed inter- pretation of the existing regulations-concur in the above mentioned view. Nevertheless the trade in frozen and chilled ‘meat is growing daily more extensive. In the year 1909 no new cold storages were erected in Australia, but in the Argentines on the other hand, two already existing cold storage- plants were greatly enlarged, and in Venezuela, too a new cold-store in- stallation for meat transport was built, and cargoes are expected from this country in 1910. The world’s production of frozen and chilled meat amounted in 1909 to : 561 535 tons against 481.170 tons in 1908 and 465,561 tons in 1907. Of these sums 547.366 tons or + 97 per cent, went to England in 1909; the remainder was shipped shiefly to South America, to the Pailippines and to Vladivostock. For various causes to which we have already drawn attention above, the export trade of North America and also of Canada is declining. In 1909 the price of frozen meat in Chicago and New-York was sometimes higher than in London: and in the first weeks of 1910 large quantities of meat were actually imported into New-York from Australia and New-Zea- land, which suggests the fact, that America has some inclination to become an importer instead of an exporter of meat. A us tra lia began in 1909 with the export of chilled beef, the ex- port trade having so far been chiefly confined to frozen mutton. This alte- ration has been rendered possible by the application of a new procedure, according to the Linley method, by means of which the air in the chill- rooms is completely sterilized which will doubtless have a great future. 36% 564 We have been obliged to limit ourselves in answering the question put to us, for the subject is many-sided and capable of many different views. But one perceives more and more that with regard to home affairs Cold Stores now consitute an integral and indispensable part of the public- slaughter-house. - For over-sea countries which, like the Argentines, Austra 1 i a and New Ze a land, are rising into importance and where the cattle stock can still be largely increased, the exploitaton of the refrigerating industry is of the greatest advantage. They were thereby enabled to compete with European countries in the meat market and their prosperity is largely connected with the rise of this trade. It is therefore undeniable that it would be of the greatest benefit for these countries if the remaining States of Europe would adopt the same attitude towards the importation of frozen meat. --- In the above pamphlet, however, we have pointed out that there is at present little hope of this taking place. As regards the Netherlands in particular, we believe, that the facilitations for the import should not be ad- vised at present, for the reasons above given. 565 The Sanitary State of Argentine Cattle. By Doctor Ferdinando Perez, Minister of the Argentine Republic at Vienna. The refrigerating industry applied to the preservation of butchers' meat is assuming every day a more considerable development. The augmentation especially of the population of towns, the aspirations so justified of the labouring classes to a greater degree of comfort, the exigencies even of urban and industrial life which demand a more nou- rishing alimentation, here we have the important causes which explain the augmentation in the consumption of the meat of the Ox. The increase of the European cattle has not followed a parallel development, capable of satisfying this always increasing consumption. Isolated by protective custom tarifs, each state has witnessed the inequality in balance produced thereby, and the enhanced prices of meat, reaching intolerable figures. The cattle of Europe not being able to cope with the consumption, the people spontaneously have looked to the other side of the Atlantic, where numerous herds of oxen feed on the immense fertile prairies. Here comes in the refrigerating industry which will obviate the in- conveniences of long distances, and which will place within the reach of European consumers, at low prices, the food which they stand so much in need of. | Such is the rôle of this refrigerating industry, a rôle of a great economic and social range. These considerations explain the extensive development of the chilling industry in Argentina, which occupies to-day the first rank among the countries exporting butchers’ meat; the capital absorbed in it surpasses already more than 100 millions, and the continually increasing demands of the consuming markets are now necessitating the installation of new establishments. This development of the refrigerating industry is intimately associated with the sanitary life of the cattle. It is evident that in a country where the cattle would possess bad sanitary conditions, where they would be decimated by grave and continual epizootic maladies, the refrigerating industry could not prosper. Certainly 566 the progress of this industry in Argentina by itself speaks sufficiently on the sanitary state of Our cattle. * *. I might then have dispensed with coming among you to speak of it to-day. Another consideration which is derived from simple good sense Y: would exempt me again from this task. This consideration is the following: In 33 years, from 1875 to 1907; the Argentine Republic has exported 5,488.685 oxen : England alone has consumed, in 1908, 266, 327 tons of chilled meat. Well, gentlemen, I ask you if you know a single epizootic malady of European cattle, I ask you if you know the least alteration of the public health due to this colossal exportation. Every reply to this question must be absolutely in the negative if it agrees with the exactitude of facts, and if it is marked with sincerity. In spite of these considerations I believe it is my duty to come to- day to speak to you on the sanitary state of the cattle of the Argentine Republic, so unjustly criticised. It is sufficient to reflect a little on the conditions which preside in the raising of the herds in my country, to be convinced that they satisfy all the exigencies of the best hygiene. To live in the open air, in a climate remarkable for purity and mildness, on pasturages always green, is there not here, gentlemen, an ideal situation to enjoy the best health * Such is the case for the Argentine cattle which does not know the . grave inconveniences of confined air, and of stabling. They are born, grow and fatten in the open air, breathing always the pure and life-giving air of our pampas which extend from the Atlantic to the Cordilleras. The proof that in these conditions the Argentine cattle attain the maximum of resistance to the attacks of micro-organisms is furnished by the study of diffusion of bovine tuberculosis in our country. -- Better than any other malady, tuberculosis can give us the measure of this resistance. Cattle which well resist tuberculosis, which are less affected by it, can be scientifically proclaimed the healthiest. It is the same in the human species. Is it not tuberculosis, indeed, which furnishes the value of the physiological resistance of the organism, is it not tuberculosis which under-mines slowly the sources of health while imprinting on the offspring a distinctive mark of physiological poverty which culminates in the entire destruction of families, and would end in the destruction of the race if the prophylaxy did not intervene to arrest its diffusion ? Certainly, the rearing of herds of oxen in Argentina realises the ideal conditions for preventing the propagation of tuberculosis and for favouring the cure of animals affected by it. - Professor Vallée of the School of Alfort, in speaking of the fate of tuberculous bacilli outside of the animal organism, rejected on the pastu- rages, has expressed himself thus: 567 For a long time experiments have been made on the resistance of the tuberculous bacilli outside of the organism. We know very well, says he, that if it preserves in this way its virulence sufficiently long, its culture is impossible in the external surroundings. This contagion is already very attenuated in the dried expectorations, it is still more so in the expectorations which fall on the prairies and on the fields exposed to the action of the solar rays. And it is to be expected that the dejections which fall on the prairies are not dangerous for long. The best means of making a tuber- culous animal inoffensive is to place it in the open country. In this way, the bacilli which it expels are disseminated and one accords a preference for their destruction by natural means before they can reach a new organism. In the point of view of the diffusion of tuberculosis it is necessary to distinguish in the Argentine cattle two great groups. The first group com- prises the Creole animals, remarkable for the rarity of tuberculous lesions among them. The second group contains the cross-bred animals, tainted more often with tuberculosis but in less proportions than the European animals. The veterinary doctor, Charles Robin & says that in the abattoirs of the Province of Corrientes, submitted to his inspection, he had not found a single case of bovine tuberculosis with evident clinic symptoms; in the autopsies which he made, in restricted number, it is true, he has never observed any. Mr. veterinary Godoy in a report addressed to the Cattle Office in 1907 declares that : in the Saladero 'Santa Elena, submitted to his inspection, from the month of April 1902 to the month of October 1907, he had not observed a single case of bovine tuberculosis. This slaughter-house kills 40,000 Creole animals per year, coming from Corrientes and Entrerios. In the Province of Buenos Ayres at Bahia Blanca Mr. Diehl carried on during 9 months, at the request of the Cattle Office, minute researches in order to make himself acquainted with the diffusion of tuberculosis. He examined 2.700 Oxen and met three cases of tuberculosis. I might multiply these citations all as favorable and which place in the open light this remarkable resistance of Creole cattle to the tuberculous contagion. This immunity is derived from the diffusion of the herds on the immense stretches of land and from their being reared in the open air. In proportion as the range of a given number of cattle is curtailed, the cases of tuberculosis augment also. But how great is the difference from that seen in Europe. To give you every guarantee I will quote the statistics of the great slaughter-houses of Buenos Ayres where the sanitary surveil- lance is really irreproachable and carried out with great security. The very competent, and well chosen, veterinary corps attached to the Establishment fulfils its task with a zeal which has merited many times the eulogies of the population. Just think that in these abattoirs between 400 and 500 thousand cross-bred oxen are slaughtered every year! Well, the proportion is on an average of 1°/6. Here are the exact figures: 568 Year 1901: Animals slaughtered: Steers Cows Tuberculous steers . Tuberculous cows Year 1902: Animals slaughtered: Steers Cows . . . Tuberculous steers . Tuberculous cows Year 1903: Animals slaughtered: Steers Cows . Tuberculous steers , Tuberculous cows Year 1904: Animals slaughtered: Steers Cows . Tuberculous steers Tuberculous cows Year 1905: Animals slaughtered: Steers g * Cows Tuberculous steers . Tuberculous cows Year 1906: Animals slaughtered: Steers Cows Tuberculous steers . Tuberculous cows Year 1907: Animals slaughtered: Steers Cows . . Tuberculous steers Tuberculous cows . . 336,133 84.902 998. 531 267,378 , 109.432 624. 454. . . 260.501 . 139,501 T23 539 . 274,745 . 125.107 347 479 . 270.194. . 109.803' 554 638 . 264,731 . 120.437 837 724 232.240 . 146.102 1.706 1,084 569 If we examine the results of tuberculinisation in the dairy farms of the town of Buenos Ayres we find the following statistics: Year Tuberculinised animals Tuberculous °ſo 1897 1444 343 23-75 1898 2420 319 13:18 1899 1758 297 16:59 1900 2208 348 1675 1901 1640 194 11.83 1902 2478 75 | 3:03 1903 --- 1758 28 1°59 1904 - 21.89 39 1.78 1905 1165 219 1878 1906 1465 239 15'90 1907 1454 267 18:08 1908 1530 Aº 597 19-53 You see then, Gentlemen, that even in the most favorable conditions realised by the prolonged stabling, the percentages of tuberculous animals among the Argentine cows are far from reaching alarming proportions, Let us change the continent and transport ourselves to Europe, in some countries of Europe; in order not to impose on your attention, let us stop in Germany and in Denmark if you have no objection, two coun- tries where the laws of hygiene are applied with an exemplary severity. Let us look here from the point of view of the tuberculosis in Denmark. The Service of Inspection of butchered meat gives the following percentages at Copenhagen: - from 1888 to 1895 from 1628 to 29.66% 1896 25.329/, 1897 26.289/. 1898 29.289/. 1899 32.31% 1903 33.74% Notice that the point in question is that of animals destined for con- sumption. In the same conditions the percentage does not exceed 1% in Argentina. These Danish cattle return to Germany after a stay in a lazaretto in order to be submitted there to a sanitary observation. Here are the results of the German inquiry. In 1905, pass: through the lazaretto of Altona Behrenfeld 25.655 oxen with 23.2% of tuberculosis; through the lazaretto of Rostock Warnemünde 14,185 oxen with 40% of tuberculosis; 570 through the lazaretto of Lübeck 9.105 oxen with 21°/o of - tuberculosis; through the lazaretto of Appenrode 27,731 oxen with 19.8% of tuberculosis: * You see that we are far from these percentages in Argentina. Let us pass to Germany. Here is what happens in the abattoirs of Prussia: - Year 1898: Number of abattoirs . . . . . . . . . . . 358 Oxen slaughtered . . . . . . . . . . . 1,667.257 , tuberculous . ge tº & tº g . . 162,089 Percentage % . . . . . . . . . . . . 9.72 - Year 1899: .* Number of abattoirs . . . . . & e < * * 381 Oxen slaughtered . . . . . . . . . 1,050.312 , tuberculous * * º . . . . . . 169,006 Percentage % . . . . . . . . . . * e º 16:1 Year 1900: Number of abattoirs . . • * g e s ſº a º 398 Oxen slaughtered . . . . . . . . . . . 1,169.582 , tuberculous . . . . . . . . . . . . . 194.787 Percentage "lo . . . . . . . . . . . . 1663 The abattoirs of Saxony give in 1898 30'46"/o 1899 29.76°/o 1900 - 30.74% You notice again that we are far from the percentages of the great abattoirs of the town of Buenos Ayres. - But you will say: it is not surprising that higher percentages are established in Europe, for here the sanitary police regulations for animals are more efficiently carried out by a body of more competent veterinary surgeons. n Well, gentlemen, to reply to this objection I will quote to you the following fact. Germany had sent for our International Exhibition a number of cattle — I believe, 36 oxen. As the law demands, these animals on their arrival, were interned in the lazaretto in order to be submitted to a sanitary observation. The veterinary surgeons concluded from this observation that almost all the animals were tuberculous, and that as a consequence of the terms of the 571 regulations of the Sanitary Police, they ought to be slaughtered. For some special considerations, since it was a question of chosen animals sent offi- cially to the Exhibition, they were not sacrificed. Their immediate embarcation for Germany was ordered. From the very first this act occasioned comments little agreeable to my country. One had acted, it was said, under pressure from interested English importers. These animals, declared for the most part to be tuberculous by the Argentine Sanitary Authorities, arrive at Hamburg. There, they were examined by a Commission of 30 members, nominated by the Minister of Agriculture. This Commission recognised that 70% of the animals were tuberculous. What is observed in Germany, is observed everywhere in Europe. From the point of view of tuberculosis, the situation of the Argentine cattle is excellent. We are not proud of it however, and the Argentine Govern- ment has taken severe measures to attenuate the diffusion of this malady. Not content with that it realised the first the wish of the Budapesth Con- gress which required the different Governments to give to experimenters the means of making experiments for the cure of bovine tuberculosis and of bovine — vaccination. Le Recueil of veterinary Medicine of Paris of the 15" of March, 1907, published the following article on this subject: To the end that the Argentine Republic should profit from the new discoveries on the treatment of tuberculosis, Señor Ezequiel Ramos Mexia, the Minister of Agriculture at Buenos Ayres, had in July 1906, charged our colleague Herr Professor J. Lignières, Director of the National Institute of Bacteriology, to make the following proposition to persons who have occupied themselves with this question: The Government places, at its own cost, at the disposition of savants who possess an efficacions remedy against tuberculosis, the bovine reproducers (breeding bulls) of great value imported from Europe, and which are slaugh- tered as reacting to tuberculine. These animals, whose average price is £ 400, and which count at times among them champions of the very first order bought in England for as much as £ 1,600 to £ 2,000, are in excellent apparent health, Surrounded by meticulous care, and their tuberculous lesions are most often of a minimum degree. \,, It appears evident that if a treatment is to be efficacious, it is with such subjects. It would be quite otherwise if it was a question of curing Some emaciated cow, badly nourished, with cavernous lungs, and with massive lesions. Of all the savants visited by M. Lignières, equally in France as in Germany, Italy and in Belgium, one only up to the present, the Professor von Behring, has accepted the proposition of the Argentine Government. The former, M. Lignières, who was interesting himself at first only in the curative treatment of tuberculosis, has consented afterwards, on the 572 eager desire expressed by the Professor Behring to have at the same time his bowo-vaccine tried. -- º It is with this aim that the Articles 9 and 10 have been added in the contract which we give below. Those interested will be able to remark that Article 4 leaves impli- citly the door open to other experimenters. C on tract. Between the Minister of Agriculture, on the one part, and Herr Pro- fessor von Behring, on the other part, has been agreed as follows: 19 The Argentine Government, desirous of utilising the imported reproducers of the bovine species which have reacted to tuberculine and which are actually sacrificed without any profit as tuberculous, engages itself to instal, under its immediate surveillance, a special hospital to receive therein these reproducers. All or part of these will be placed at the disposition of the Professor Behring who assents to have his curative method applied at Buenos Ayres and whose tests have been scientifically made under his supervision on Some guinea-pigs, sheep and cows. 29 Herr Professor Behring engages himself to send to Buenos Ayres his first assistant, Herr Dr. Paul Roemer, to apply the curative treatment to the imported tuberculous oxen. The duration of the mission of Herr Dr. Roemer will be of one year. - 39 As remuneration, Herr Dr. Roemer will receive, at the moment of the signature of the present contract and as expenses of the outward journey, the sum of 2,000 marks. From the day of his arrival at Buenos Ayres, he will receive a monthly honorarium of 1,000 piastres paper money. After the accomplishment of his mission, Herr Dr. Roemer will receive a sum of 1,000 piastres as expenses of his return journey. 40 The Dr. Roemer, charged with executing the instructions of the Professor Behring, will alone be judge of the nature, of the form, and of the intensity of the treatment. He will not be able to demand the placing at his disposition of all the imported reproducers who react to tuberculine, but only of one part of these. t The right of controlling the progress and the results of the treatment will belong to a Special Commission nominated for this purpose by the Minister of Agriculture. In no case will the Commission be able to occupy itself with the mode of fabrication of the remedy nor demand that it may be placed at its disposition. 50 When, on the advice of the Dr. Roemer, the treated bovine reproducers will be considered as practically cured, he will have to furnish the proof of it to the Commission. If such is the opinion of this Commission, the cured animals will be handed over to their respective proprietors and their cure controlled periodically during a period of at least three years 573 ſ under the surveillance of the said Commission. A certain number of the treated animals will be sacrificed and autopsied before the Commission at the moment when the Dr. Roemer will have to demonstrate the results of the treatment. The animals which would not be cured will after a delay of six months be slaughtered and autopsied. . In the end, some tuberculous reproducers will be sacrificed as wit- nesses without having undergone any treatment. 69 The Argentine Government engages itself to pay the value of the curative product to the Professor Behring in the proportion of 1 piastre paper money for each injection, the total treatment of each patient being not to exceed ordinarily ten of these injections. 7" In case the Argentine Government or the Professor von Behring should judge the continuation of the mission of the Dr. Roemer up to the completed year to be useless the present contract would be cancelled in full right without any indemnity on the one part or the other, except the 1,000 piastres provided for the return journey of the Dr. Roemer. 8° Let the mission have lasted a year or not, if the results obtained have proved the efficacy of the treatment, Herr Professor Behring engages himself to make the Argentine Republic profit practically from his remedy after the departure of his representative. Art. 9. – In addition to the obligations contracted in the preceding Articles, the Professor von Behring engages himself to have in the same time his bovovaccine tried by the Dr. Roemer on some oxen placed at his disposition by the Argentine Republic and specially destined for that object. The Argentine Government will pay the value of the bovovaccine employed in these trials. Art. 10. — The programme of the Experiments of bovovaccination will be decided in advance; it will require the assent of Herr Professor von Behring. Berlin, the 12 February 1907. Conformably to Article 10, Professor Lignières has composed the following programme, accepted by Herr Professor von Behring, and which gives, with the preceding contract, the exact note of the rigour and of the importance of the experiments which are to be made at Buenos Ayres. Programme of the experiments of bovovaccination to be realised in the Argentine Republic in conformity with the contract agreed upon and executed with the Professor von Behring: The experiments will be realised in the following conditions, on some bovidae duly marked, aged from 20 days to 3 months, born in the locali- ties free from turberculosis and submitted previously to the test of the tuberculine which they will have to sustain victoriously. A first series will comprise 50 animals of which 20 will serve as witnesses and the 30 others will receive from the Dr. Roemer the first 574 vaccine. This first vaccine will be inoculated by the Commission to some experimental animals in order to determine its pathogenic. qualities. After the first vaccination, witnesses and vaccinated will be left to- gether in the normal conditions of life, but, without promiscuity with other bovidae. When the three months will have elapsed, witnesses and vaccinated will be tuberculinised, then two of the vaccinated will be slaughtered in order to be autopsied and some of their organs and tissues, healthy or not, inoculated in some of the experimental animals. sº Afterwards, the 28 vaccinated animals remaining will be inoculated by the Dr. Roemer with the second vaccine. This second vaccine, as the first, will be inoculated in the same conditions and for the same aim to Some experimental animals. The vaccinated and witnesses will be always together and in the normal conditions of life. Three months after the second vaccination, the vaccinated and wit- nesses will be submitted to the test of the tuberculine. As soon as the result of this is known, two of the vaccinated will be slaughtered in order to be autopsied and their organs and tissues, healthy or not, inoculated by the Commission to some sensitive animals. At the same time, that is to say at the minimum six months after the second vaccination, the 24 vaccinated animals remaining and the 20 wit- nesses will be submitted by the Commission to the test of the bovine tuberculous virus. That is to say: 5 vaccinated and 5 witnesses will receive the virus in the veins; 5 vaccinated and 5 witnesses will receive the virus under the skin; 14 vaccinated and 10 witnesses will be placed in a restricted space, in intimate but natural contact with some tuberculous bovidae, - Six months after the test inoculation, all the survivors will receive an injection of tuberculine. - - Then will be slaughtered, reacting or not to the tuberculine, 2 vacci- nated and 2 witnesses inoculated in the veins, 2 vaccinated and 2 witnesses. inoculated under the skin; as to the vaccinated animals and the witnesses submitted to the test of natural contamination, none will be slaughtered, except those which would react manifestly to tuberculine. * * One year after the test inoculation, the remaining animals will be a second time tuberculinised. There will be killed now, reacting or not, 2 vaccinated and 2 witnesses tested in the veins; 2 vaccinated and 2 wit– nesses tested under the skin, as well as the animals exposed to natural contamination which would react. At last, one and a half years after the virulent test, all the animals which would remain will be slaughtered and autopsied after having under- gone a last injection of tuberculine. After each autopsy, the Commission will have to inoculate to some animals capable of being affected the lesions 575 which will be likely to be encountered and the pulps of organs or of tissues healthy in appearance whose tuberculous integrity they would believe they could control. The second series will comprise equally 50 bovidae, which will be placed in a different region from the first; they will be submitted to the same test as those of the first series, but the experiments will not com- mence until a month after the first. The third series will begin a month after the second and will comprise the same number of animals located in a place distinct and the same experiments as the two preceding series. A fourth series will be formed by 30 bovidae of which 10 will be vaccinated at the same time as those of the first series, 10 at the moment of the second and 10 at the same time as the third. These animals will be kept without any intervention of tuberculinisations in the ordinary con- ditions of life. One year after, 10 of these animals will be tuberculinised, then sub- mitted to a test of contamination by the virulent bovine tuberculous bacil- lus, in the same time as the witnesses. The same experiment will be made with 10 other vaccinated ani- mals two years after the vaccination. 4 * At last, the 10 last ones will be employed in the same conditions at the end of the third year. To facilitate the researches and the observations, the animals to be autopsied will be as soon as possible, and in all the experiments, brought to Buenos Ayres. For each Series, two veterinary surgeons, proposed by the Commission of Control, will be allotted to the sanitary surveillance of the animals; they will note down all the observations on a special and numbered register. Paris, the 1st February 1907. J. Lignières. It is understood that in the three first series, I shall have the right of employing in the first series some vaccines made at Marburg and transported to Buenos Ayres; in the second, some vaccines freshly prepared at Buenos Ayres by the Dr. Roemer; and, finally, in the third series, a single vaccine in the place of two. Marburg, the 14 February 1907. * E. Behring. De cree nominating the Commission charged with controlling the progress and the result of the experiments. Buenos Ayres, the 17 February 1907. The contract which has been passed between the Professor Joseph Lignières, representative of the Government and the Professor von Behring, 576 in his own name, for essaying in Argentina the method of the latter for the treatment of bovine tuberculosis and that of preventive immunisation against this same malady being approved, and the Dr. Roemer, assistant of the Professor Behring, being bound to come in his stead and place. Inas- much as it is agreed to study the progress of these experiments and to gain a knowledge of the results of them. -- The President of the Republic De C re es: Art. 1. Are nominated the Dr. Eliseo Canton, Senior of the Faculty of Medical Sciences, the Dr. Carlos Malbran, President of the National Department of Hygiene, the Dr. José Penna, Director of the House of Isolation, the Dr. Pedro N. Arata, Director of the Higher School of Agronomy, Veterinary Surgeon and of the Municipal Chemical Office, the Dr. Julio Mendez, ex-Professor of the Faculty of Medical Sciences, the Dr. Fermin Rodriguez, junior, Director of the Sanitorium Santa Maria, the Professor Joseph Lignières, Director of the National Bacteriological Institute, the veterinary Surgeon Dr. Ramon Bildart, Inspector General of Animal Sanitary Police, in order that, constituted as a Commission, they may follow the experiments of the Dr. Roemer and give an account to the Executive Power of their results. Art. 2. The Divison of Cattle Rearing will furnish to this Commission, each time that it will demand it, the elements of which they also dispose for the accomplishment of its task. Art. 3. That this is to be communicated, published and inscribed in the National Register. Signed : Figuerva Alcorta. E. Ram on Mexia. The Dr. Julio Mendez having found it an impossibility to form part of the Commission, the Government appointed in his place the Dr. Disiderio Davel, recently returned to Argentina, after having worked one year with the Professors Behring and Roemer in their laboratory at Marburg. Unhappily the admirable efforts of the great German Savant, who is one of the purest glories of humanity, did not end in a favorable result. The Argentine Government had done its duty, and it honoured itself in being able to render homage to the beneficent genius of Behring who has already saved so many human lives. I have now finished with the tuberculosis of Argentine cattle. A single instance of the cattle plague has never been observed in Argentina. A great noise has been made latterly on the subject of aphthous fever. This malady prevails indeed, since the month of June in the epizootic state in some of the provinces, especially towards the North of the Republic. But it is not peculiar to Argentina. 577 The cattle of the entire world are tainted with it. It exists likewise in France, in Germany, in Austria and in England, countries which refuse to admit our cattle alive. The bovine. Malaria prevails also in some provinces of the North of the Republic where it is known under the name of >Tristeza. This malady is not peculiar to Argentina; it exists also in the United States where it is called "Texas feverg and in Australia where it is named »Red Water & . - Like human malaria, the bovine malaria could not propagate itself outside of its focus. ---. & An animal suffering from malaria ceases to be dangerous in leaving this focus, for it leaves behind the mosquito, the indispensable intermediary for the inoculation of the malady. The ixodes is the intermediary for malaria in cattle. I must add that the prevention of malaria in cattle is today a deed definitely achieved by Science thanks to the remarkable researches of the Professor Lignières Director of the National Laboratory of Veterinary Bacteriology. - Gentlemen, I think, I have shown that the cattle of the Argentine Republic, from the point of Sanitary view supports comparison with the best in Europe. They do not deserve then the criticisms which have been passed on them. I know well that these criticisms are interested, and that consequently there would be no necessity to place any value on them. I have persisted however in presenting you with this long account which will, I hope, destroy definitely, these unmerited attacks. Thanks to the frigorific industry, we have become the principal purveyors of meat to England. You can believe that my country is disposed to favour by all the means possible the progress of this industry which allows it to extend its action over all the other countries whose populations suffer from want of meat. There remains to me nothing more but to beg you to be good enough to excuse me, if I have abused your kind attention. 3 7 578 The Sanitary Inspection of Refrigeration Plants in the Argentine. By Nicholas T. Suárez, Head of the Sanitary Department of Refrigerating Plants at Buenos Ayres. These establishments are subject to veterinary inspection under the sanitary police laws for animals of October 10th 1900, which in article 10 order the sanitary inspection of establishments dealing with alimentary pro- ducts derived from animals, and destined for international, or inter-state commerce or trade within the jurisdiction of the Republic. A clause in this law, which has been in force since February 1902, enacted that, from the 1st of April of the same year, the supervision of such establishments should be entirely in the hands of veterinary surgeons of the cattle breeding department. In accordance with this law and this particular clause, national inspec- tion of abattoirs began on the first of April 1902; up till then they were inspected by veterinary surgeons of the Public Health Board of Buenos Ayres. In 1907 when the present office was established, new inspectors and veterinary assistants were required for each abattoir where there had never been more than two inspectors; this was because of the larger number of cattle killed, and was necessary for the supervision of the various depart- ments annexed to the establishments, where the different processes are carried out. At the present time there are in permanent employment in the eight abattoirs, twenty-two holders of veterinary diplomas and eighteen veteri- nary assistants, altogether forty employees. Under special circumstances, either when there is a specially large number of cattle to be killed, or when it is thought necessary to increase the amount of Supervision, the sanitary staff of each establishment is increased. It should be remembered that the estab- lishments have an almost equally large Staff of classifiers, assistants, em- ployees in the drying rooms, markers etc. to supervise the preparation of the meat, and who serve as auxilliaries to the state inspectors. 579 During the same year (1907) the department was deputed to draw up regulations for cold stores, salting and preserving houses, as ordered by article 12 of the sanitary police regulation for cattle, N° 2, of the 4” of October 1906, which read as follows: "The Breeding department shall give special instructions for the sanitary service of cold stores, salting houses, and other similar industrial establishments, according to the requirements of each district, in order to obtain the most efficient inspection service.< The head of the department approved, with the exception of certain modifica- tions of the proposals which were placed before him, and these new regula- tions wherein the special general hygienic regulations to be followed by these establishments were specified, namely the obligations incurred by com- panies towards veterinary inspectors; the conditions which are to be satis- fied by persons handling the meat; and the fines incurred by infraction of the different regulations, were put into force by an act of the same date. The sanitary inspection of these establishments consists in: the inspec- tion of live stock, the inspection of animals after being killed, and supervision of the products handled, up to the time of their being des- patched. The inspection is carried out as follows: Inspection of live stock. Every herd of cattle which arrives at the establishment is inspected, and its certificate of source taken either on unloading, if it comes by rail or river, or just before its entry into the establishment having the abattoir, if it comes on foot. The animals provided by markets, such as those of Tablada and Liniers, are accompanied by their veterinary certificates: if the abattoir inspector suspects that they may have become infected on the way, he in- spects them afresh; he may even have them isolated to be examined when convenient. As concerns animals from an infected area, or suffering from garra- patis they may be accepted under the following conditions: 1. When they come from sanitary establishments. 2. When they come from fairly sanitary establishments, with certifi- cates of their having been washed at the times fixed by the breeding de- partment, provided they come to the abattoir direct by rail or river. 3. Animals affected with garrapates can on no account be accepted ‘unless the establishment is outside the infected area. Lastly, those coming directly from rural breeders without passing through the market, that is to say the larger number of the steers, as well as sheep and pigs, and which have no certificate of veterinary inspection, are to be examined very carefully. If after inspection of a herd from any source whatsoever, there is a certainty or merely a suspicion that one of the diseases mentioned in article 4 of the general sanitary police regulations 37:6 580 for animals, relating to exotic diseases, or those in article 6 relating to con- tagious diseases resembling distemper, which exists in the country, the vete- rinary inspector must act according to the clauses of said regulations: he must have the herd isolated and immediately inform the inspection depart- ment by telegraph, giving the number of the way bill the date of leaving the place where it was issued, and the name of the establishment. * If aphthous fever is observed, all the animals of the herd are killed immediately, as well as all those with which they have come into contact; the enclosure or depot where they have been is desinfected, and no animals are allowed to enter the establishment until fifteen days after the desinfec- tion of runs, depots, stables etc: For isolated cases of anthrax there are the following special in- structions: When cases of this disease occur in animals which have not been more than two days in the establishment, and, if, from information obtained, or in the opinion of the veterinary inspector, the disease has been contracted at the place of departure, or on the railway, the procedure is the same as for the cases previously cited in the general regulations. When the anthrax occurs in animals which have been in the estab- lishment more than two days, and when, in the judgment of the sanitary inspector, the disease may have been contracted there, the herd is isolated for forty-eight hours; then, if no new cases occur, slaughter is authorised; otherwise the herd remains isolated. But if the abattoir authorities wish to kill the animals of the herd, it must furnish the facilities necessary for their classification, and must leave no doubt as to their sanitary condition, by taking the temperature of each animal, those having a temperature of above 39.5° C. must be rejected and isolated again. When this disease occurs among animals which are to go into winter quarters, or which are to stay more than one month in the enclosures of the establishment, the veterinary inspector must have the infected herd iso- lated, whatever number of cases are observed, and order all the animals to be vaccinated immediately, as well as all animals which happen to be in the same enclosure. - When the pastures are infected with this disease, the sanitary inspector must advise the establishment to drain all ponds and to encirle the ground occupied, with drain tiles, in order to keep the animals from being infected. If the establishment owns several pasturages they may also be advised to keep unused for 2 or 3 years those which are infected with anthrax after the ponds have been drained. As concerns mange in sheep, herds containing more than 5"/, of mangy and scurfy animals are to be rejected. As for the others, the animals must be washed immediately, and this must be repeated a second time after ten days. If they are killed after the first bath, a fine of 50 centavos per ani- mal is incurred. 581 Another function of veterinary inspectors of abattoirs is to make sure, when animals arrive either by rail or river, that the transportation company conforms to the general sanitary regulations of the police, as to the disinfection, that is to say, if the car, boat or barge which has carried the animals, has been disinfected before loading. A new disinfection must also be proceeded with if any case of contagious disease has occurred during the journey; this last regulation is also applicable to the enclosures, runs, stables and slaughter rooms of the abattoir. They must also see that the animals kept in the enclosures or stables are not ill treated, and do not want for the necessary food and water, which might lower the quality of the meat. - Also they must examine post mortem any animals found dead in the cars, barges etc., as well as any which may die while in the pasturage enclosures or stables of the establishment, and examine the blood for bac- teria in laboratories which possess every facility for veterinary inspection, and for scientific research. If the establishment is allowed to take the dead animal to the tanks this must be done in a special wagon, entirely lined with zinc and completely closed; the work must be carried out on the post mortem table which is to be found in every establishment, that is, when the hide and flesh can be used to make grease for industrial purposes. In cases of con- tagious disease, these parts are placed in a disinfecting oven, or sterilised in vessels intended for this purpose, where they are placed with the hide. If, when a post mortem examination is carried out at the actual place where the animal dies, anthrax is detected, the animal must be burnt innme- diately. The duty of the veterinary assistants is to go the rounds of the depots and pasturage enclosures of the establishment two or three-times a day, and inform the veterinary inspector of any fault in the Sanitary conditions, who then at once makes an investigation and does what is required. The veterinary inspector may forbid slaughter of animals under the following conditions: If they have made a long journey on foot or by railway, they must not be killed until they have rested at least 48 hours. If there are any females in a very advanced state of gestation. If any of the animals are affected with feverish diseases even when non-contagious. * * -- He may allow slaughter outside the regulation times and outside the slaughter rooms, but under his personal supervision, in the following cases: If there are any animals having recent severe injuries. If there are any animals affected with serious but not feverish illnesses. Lastly, the head of the sanitary service at each establishment shall require from the manager, a daily report stating the species, the numbers of the way bills of the cattle, the source, and the number of animals to be 582 killed on the following day; and another report giving similar infor- mation on the entries of the same day, which are put down in record books of animals slaughtered, which must state on the 1s' and 15" of each month the slaughters and seizures made, and be sent to the general inspection service of the establishments, as will be seen below. Exam in a ti on of S laughter e d an im a 1s. After inspection of the live animals, and after they have been washed, either by immersion or by a shower, according to the method of the esta- blishment, they are slaughtered in slaughter rooms fulfilling the hygienic con- ditions required by the regulations in force. As soon as they have been disembowelled the meat is examined by the naked eye, and under the microscope, and all that is judged to be injurious to the public health is seized. * Stamp for quarter of beef. In case they are slaughtered too rapidly to be inspected at once, the animals and their organs are numbered, and hung upon a Series of hooks which hold from eighteen to twenty animals, where the inspector examines them one by one, and notes down the number of any suspicious cases in order to re-examine the animal of that number more carefully. When the animals are perfectly clean and ready to be sent to the drying room, they are examined a second time by a veterinary assistant who is always at hand. The veterinary inspector must make a new exami- nation in the drying room, before the meat can be marked with the offi- cial stamp. - The stamping has been changed; the label placed on each quarter has been done away with, and has been replaced by an ink mark direct on the meat with a metal stamp. 583 Cattle are stamped on each quarter, the hindquarters being mar- ked on the loins, and the forequarters on the breast under the shoulders. Sheep are marked with two stamps on the hindquarters if they are in one piece, in the same way as for cattle ; when they are cut up, each piece is stamped. Stamp for sheep and pigs. Quarters of beef and mutton after being frozen or chilled are wrap- ped in a cotton cloth stamped thus: REPUBLICA ARGENTINA" MINISTERIO . . . . . . DE . . . . . . | AGRICULTURA INS PEC (; 10.NAD 0. Stamp for the cotton coverings. Lastly assignments of meat for export are accompanied by a certificate, made out by the head of the department, certifying that they have been properly prepared. •, The veterinary inspector also superintends the section where the parts, such as tongues, livers, kidneys, hearts, tripe, brains, tails etc., are prepared by freezing, and afterwards wrapped in waxed paper, and packed in boxes with the inspector's mark branded on them; all operations being carried out under the most hygienic conditions. 584 The packing of the different parts which are shipped in a frozen state has been subject to one alteration; they are now despatched separately, the authorities of the British Board of Agriculture having exacted this in order to facilitate inspection at the ports of destination which has been effected since then by examining each organ separately. * aepublica ARGENTINA º **- : - MINISTERIO DE AGRICULTURA ! Division, DE GAnADERA, zoologia- - T - . ... " - ºx - .. - . ... ." .*.*.*.* 2. Policia v ETERINARIA * : … - - - - - - -- w" rº-. * M- * **** * wº s", - * , - - * *. - w * * , - * * *- - - - ~ * - - - -r * -- -- - - - - - - - - - ... ?" - - - - - - ** - " ", a *-** - 5 e * ~t, -* - - ~~~ * - - * , *r- - * * --~" r- ,-- --~~-- Y - - - - ~ *- - - * **- - •. ºf . Tº ". -S . * *** - - - - - - r • *- - - - - - - - - > * , - 4. 1. - * - - ~ - p - • - zº *- : * ~ * - ~ - - * - ~ w- - *. - - • • * * + - V. ... " ~. - :- - - * -- - ... ', r- -- ~~" …"- - - -- - - •w -- --- - - ~ - - ... • * - --- ~ * : * -- - - • * ~ * ~ * - -- - • a. * ~~} - * ~ - - - J. : : * * *. • - - ... → -- ~~~ > * .. - - > J-" - -- - * ~, * * * **. T- x- - - * i. --, * * - -, - " - -- - - f Brand for boxes of parts. Other sections which are constantly superintended are the cold rooms for refined suet, for preserved meat and for preparations of pork, (there are only four cold stores for the latter). Suet as well as preserved meat is placed in tin boxes, carrying the inspection stamp in relief. Relief stamp on tin boxes. As concerns preparations of pork, all of which are for home consump- tion at present, they are accompanied with the certificate of the veterinary inspector. The hams, thin lard, thick lard and bacon only are stamped, with the oval stamp bearing the name of the establishment producing them. All products are analysed in special laboratories only those being used which do not contain any thing injurious to health. 585 The general inspection department of these etablishments controls all the processes in the preparation of meat; it is forbidden to make any alte- rations in the approved processes without permission of the Breeding De- partment. The Minister of Agriculture is engaged at present at a measure, drawn up by the chemists and veterinary inspectors of the Breeding De- partment, dealing with the conditions which must be fulfilled by receivers of food products derived from animals, whether imported or manufactured in the country. It is stated therein that the lining of the boxes as well as internally soldered joints should be of fine tin, that is to say, tin which does not contain more than one per cent of lead and 005 grammes of arsenic or antimony. No receptacle used must show on analysis a trace of any substance considered dangerous to health, but must have been subjected to receut sterilization; neglect of any one of these conditions is sufficient cause for rejection. Stamp for pork products. Seizure must be made in the following cases: To t al Seizure. The whole animal is seized : For general tuberculosis, and 1, when there are any large tuberculous lesions in the organs in the cavity of the Thorax or in the abdominal cavity. 2. When lesions are found in one of the serous organs and when there are embolic collections in the organs of both these cavities. 3. When any tuberculous lesion of whatever kind is accompanied by extreme emaciation. - - 4. When there are any lesion in the muscle or in the intra-muscular ganglions, or in the bones. * 5. When miliary feverish tuberculosis is present. 6. When general tuberculosis is present in the form of miliary erup- tions in all the viscera, and particularly the spleen. 586 For bacteridian anthrax, complete seizure including the hide. In bacterian anthrax, the meat only is seized. **- In apthous fever, when the meat is feverish. For contusions, when they are general and deep. For natural death, when it follows disease. For accidental death, if not immediately followed ...by bleeding and gutting, whatever the appearance of the animal. Jaundice in cattle, when all the tissues are of an intense yellow tint, and when the condition is anaemic and the liver out of order. In case there is any doubt, the meat is exposed to the fresh air to ascertain whether the intensity of the colour increases or diminishes. - - As concerns sheep and pigs, they must be seized whenever the flesh is found to be yellow. Y. Malignant ulcers. Feverish meat; in all cases of feverish meat from feverish diseases, as well as from fracture when the animal has not been immediately slaughtered. Poisoned meat, from animals poisoned, either by eating poisonous plants, paint having a poisonous salt base, or by a mistake in a dose of medicine. For pasteurellosis with extreme emaciation or serious general Symptons. x For general actinomicosis and actinobacillosis. For general pseudotuberculosis of sheep. For advanced piroplasmosis. For fever from exhaustion; if many cases are observed it is best to postpone the slaughter of the herd. --- For thinness or extreme emaciation. For aquous cachexy if the animal is in a state of complete starvation due to listomes. For trichinosis, if parasites are found to exist in the muscles. For cisticercosis when found in large quantities, and causing changes in the muscular tissue, when there is a serious infiltration, from adjoining parts, or when this disease accompanies another, although not sufficient in itself to justify the seizure of the animal. * For hog cholera, when, besides that of the intestinal regions, there is pulmonary or skin necrosis and fever is present. Partial Seizure. The seizure is limited to certain organs and parts in the following cases: *- Local tuberculosis. 1. When the lesions are local in the abdominal cavity, or in the thoraxial cavity. 2. When lesions of these organs, although present in both cavities, are of a small size. 3. When there are only lesions in the ganglions of the head. 587 Contusions, when only of small size. Tumors in mild form. * Pseudo-tuberculosis in sheep, and piroplasmosis in cases not specified for total seizure. g w Apthous fever, when the feverish period is over, only the affected parts are seized. 4. Hog cholera when there is no fever, and when the lesions are limited to the intestinal mucous membranes. Wounds, sores, bruises, fractures, etc. when there is no general decomposition. Alterations in single parts, such as osteomalacia, rachitism, atrophy of organs or groups of muscles, infiltrations of blood etc. More general alterations, justifying seizure of the viscera and other Organs. Lungs. For tuberculosis, pneumonia, actinomicosis, equinococosis, strongilosis, asphyxiation, cachexy. - Kidneys. For aboesses, calculs, haemorrhage, nephritis, hydrone- phrosis, actinomicosis and atrophy. - Liver. For distomatosis, tuberculosis, coccidiosis, equinococosis, cyrrhosis, chronic hepatitis, tumours and calculs. Sple en: For haemorrhage, splinitis, equinococosis. He art. For cisticercosis, pericarditis, endocarditis, and asphyxiation. T on gue. For cisticercasis, actinomicosis, apthous fever. The In test in e s. For exofagostomosis. The Brain. For cenurosis and tuberculosis. All meat seized in a refrigerator is isolated, and kept completely out of contact with healthy meat, and remains in isolation under the Supervision of a veterinary assitant, until it is taken to the apparatus for making it into grease for industrial purposes only. * Viscera which are seized for any reason whatever are taken to a destroying furnace. It should be added that frequently, when seizure is not necessary, companies are advised not to export certain meat but to put it to Some other use, either on the home market or for preservation. This advice is always followed in the case of meat with insufficient fat, or having slight bruises, meat which is yellowish without being jaundiced, the parts unaffected by tuberculosis when one organ or one part of the animal is affected. Also for pseudo-tuberculosis in sheep. The Chief veterinary inspector of each establishment sends statements of slaughters and seizures made, to the general department of inspection every fifteen days, wherein are specified the number of animals killed and their source, as well as seizures made and any Sanitary obser- vations. If any case requiring immediate attention presents itself, such as 588 apthous fever, anthrax, a large proportion of tuberculosis etc, he must immediately send a special report containing the necessary information. In order to give an idea of the slaughters and seizures made in cold stores, statistical tables for the years 1908, 1909 and for the first 6 months of 1910 are given below. - Sanitary Inspection of Cold Stores in the Argentine Republic. 1. Cattle. Animal Tuberculosis | Contusions * º, º: - * r * * Illlll 8, 18 * Illinſ) el’ 101 O Year killed * Total | Partial}| Total | Partial of seiz-|| animals . General | Local | seiz- seiz- seiz- seiz- lli’eS seized | lureS lifeS ill’eS Ull’êS 1908 706.152 2.418 13.432 154 75 774 324 2.529 || 2.971 0°42% 1909 || 818.832 || 3.108 || 16.487 || 134 || 89 |1,612 || 308 |2.687 || 3.539 || 0:43% 19101) 470.492 1.844 9,863 61 40 953 173 1.772 || 2.118 0.45% * i 2. Sheep. ------ Pseudo- * Various r Animal, tutºsis | * ...| diseases ||, ..., ºf Year killed Total Partial Jaundice Total Partial}} of seiz-il animals General | Local seiz- seiz-> seiz- seiz- ll PèS Seized Ull'êS llres Ull'es UlreS ------------- | | 1908 3,806.917 | 800 39,562 3.500 4.698 1.232 || 1.900 15.957; 7.432 0.19% 1909 2,923.072 | 637 36.500 #3200 3.264 i 1.958 || 1.450 13.610|| 7.245 0.24% | 19101) || 1,635.117 | 320 21.219 # 955 1.828 589 815 7.559| 2.679 0.16% s | - i Con clusion. c: It follows from the above statistics that the sanitary condition of animals intended for cold storage is excellent, which may be attributed to thc fact that the cattle live in the open air throughout the year, and also to the small number of contagious diseases in Argentina. As to seizures they are relatively negligible, although conditions are much more rigorous here than in Europe. * These circumstances place the country in a very favorable position for supporting the efforts to make uniform the legislation dealing with sanitary inspection of animals which are to be killed on the premises of the refrigerating establishment. As a matter of fact, if we compare the regulations governing the inspection of imported meat in several European countries, we shall find that many of them have been drawn up 20 years ago, and in consequence, -------- -- ~~~~ 1) First six months. 589 they do not take into consideration the progress which has been made in veterinary pathology, nor that which has been made in the preparation of meat by refrigeration. -- The first International Congress of Refrigeration, held in Paris, consi- dered the injustice of this state of things, and passed a resolution recommending the adoption of a uniform system in the inspection of meat. As the matter is of interest, the second Congress, held at Vienna, has passed the following resolution: - »That the International Association of Refrigeration should take the initiative in the meeting in Paris, in 1911, to form an International Conference, at which all countries which import and export meat should be represented, for the purpose of adopting an international and uniform system for the inspection of refrigerated meat.< 590 - Drinking Cups made of Ice. By H. D. P. Huizer, engineer, Hague (Holland). A detailed description of the making of ice-cups and the freezing appa- ratus together with 10 illustrations was already published in part 3 (pages 283 – 295) of the reports of the first Cold Congress (Paris 1908). Since that time, under reservation of the approved process, only slight practical changes in construction of the apparatus have been attempted, while a series of useful ice-cup refrigerators has been executed. The novelty finds continuously increasing popularity even in foreign lands. Last year the invention gained the , Grand Prix“ at the XIII Paris Exhibition of Cookery. - The sketch shows an ice cup in its protecting case of paper with wadding collar (in the la natural size). This execution was first exhibited at the Paris Cold Congress amidst great approbation, and it has since been proved to be eminently practical. For hot countries a somewhat thicker ice-cup comes into consideration, that is with 4 millimetre thickness of wall (instead of 3 millimetres), whereby with an equal content of *ſ, litre the weight becomes 125 grammes (instead of 100 gr). In the period of freezing, however, this is of no effect, because the bottom, of from nine to ten millimetres, in each case, must be frozen last and entirely, namely 15 minutes at –10% C, decreasing to nine minutes at –15° C. - The period of use for drinking every kind of refreshing drinks is 20 to 30 minutes at about 25° C air temperature, after which the ice-cup (as also the case) is absolutely useless according to the highest demands of hygiene. Trials have shown that the ice-cup is remarkably strong; it withstands an axial pressure of 150 Kilogrammes for some minutes. | The simultaneous use of the case as advertising means proved very profitable; the cost of production can by this be reduced eventually by one half, that is about 2 d. per ice-cup, while experience shows that this new, delightful manner of drinking admits of an addition of 1 d. per ice- cup easily, because the public are extremely taken by it. 591 The Nymph" A-G. in Hague (Holland), which makes use of Huizer's - patents, besides larger ice-cup plants driven with cold machines, also makes smaller refrigerators, which with ice and salt mixture can be economically and permanently driven. Unfortunately the cold machine industry still ex- hibits a want for small and cheap cold machines, which could be used advantageously in the manufacture of ice-cups. It must he remembered that with a cold production of 1000 frigorifics (that is about 1 h. p.) 50 to 80 ice-cups per hour, inclusive of cooling for the storing of this number, may be produced. 592 THE REFRIGERATION OF POULTRY AND EGGS IN THE UNITED STATES By DR. M. E. PENNINGTON Chief Food Research Laboratory, Bureau of Chemistry, United States Department of Agriculture. IN TRODUCTION º Until quite recently the study of the effect of long continued low temperatures on poultry and eggs was conducted by those connected with the industry, and for industrial ends. Advances in the quality of the product were made, but the methods of obtaining them were known only to the individual or the firm experimenting, and then, except where mechanical engineering was concerned, they were purely empirical. Because the underlying principles of refrigera- tion, as shown by chemical, bacteriological, and histological studies of flesh, have been unknown, it has been impossible for the industry to explain and remedy the varying quality of the stored products, which, though entering the freezer in apparently uniform condition, differ in quality after a given period of time. The fact that the changes undergone by poultry at temperatures below freezing are of a different character from those undergone at ordinary temperatures, as indicated by appearance, flavor, odor, etc., has led to the assumption on the part of the industry that changes in composition do not occur. The fact, too, that the changes are so subtle that the best scientific methods obtainable at present are only just beginning to detect them, together with the further fact that, for the most part, the investigations have up to this time not gone far enough to elucidate the means by which the changes noted are brought about, renders the problem from both the scien- tific and the technical viewpoint one of great difficulty as well as interest. - The general public agitation in the United States in recent years concerning “cold-stored” foods, in the sense of foods kept in a frozen condition for long periods, has been productive of more scientific experimentation and closer technical observation of such products than has been accorded to flesh foods kept at or a few de- grees above the freezing point; yet the quality of perishable stuffs 593 of all kinds so kept would demand that this phase of refrigeration be studied quite as thoroughly, if not more thoroughly, than the former. & In the following review of the work in the United States on refrigeration of poultry and eggs, an endeavor will be made to pre- sent (1) the salient points gleaned by scientific workers from a purely scientific point of view, since it is to these facts that the in- dustry must look for the stable betterment of its output; (2) the -application of refrigeration as at present practiced by the industry in the handling of poultry and eggs; and (3) a discussion of the application of the scientific findings to the practical keeping of poultry and eggs in a fit condition for food. * REVIEW OF THE SCIENTIFIC WORK DONE IN THE UNITED STATES. CHEMICAL AND HISTOLOGICAL IDATA. ON FROZEN POULTRY. Since this paper deals with the subject solely from the viewpoint of the United States, the review of the scientific work done on poul- try and eggs will also be limited to the investigations made by its workers. While there is, in American literature, a long list of papers recording observations on the effect of low temperatures on poultry and eggs, but few of them include the chemical, bacterio- logical, and histological findings upon which such statements must be based if they are to be accepted as scientific work in the strict sense of the term. That such is the case can scarcely be wondered at when one considers the long periods of experimentation involved in tracing changes in flesh held at temperatures below zero, the equipment necessary for the maintenance of such temperatures, and the comparatively recent interest in the scientific side of the subject. The first presentation of American work was almost simultaneous for several of the communications. In January, 1908, at a meeting of the American Association for the Advancement of Science, Wileya and his associates made a statement outlining the work then in prog- ress on chickens, quail, and eggs, and gave a brief report, with lantern illustrations, of the histological changes occurring in the muscle fibers of chickens kept below freezing for varying periods of time. The Journal of the American Chemical Society received in June, 1908, published in its October issue, a paper by W. D. Richard- a Science, 1908, 27: 295. 594 son and Erwin Scherubel, entitled “The deterioration and commer- cial preservation of flesh foods,” 9 and treating of experiments on frozen beef. In the last paragraph of the paper, after summing up the analytical evidence to show that there is no chemical change in beef kept in a frozen condition for more than five hundred days, this sentence occurs: ‘‘We may say that similar tests of frozen poultry have resulted similarly.” It is greatly to be regretted that the details of the work on frozen poultry were not given. The same paper, with some additions and modifications, and entitled “The cold storage of beef and poultry,’’ was presented in abstract at the First International Congress of Refrigerating Industries and pub- lished in full in the proceedings of the congress issued during the spring of 1909. In this communication, in addition to microphoto- graphs of frozen beef muscle, there are several showing chicken breast muscle sectioned in a frozen condition. The authors state that during freezing the mechanical action is such that the liquid The preservation of eggs has for centuries been a problem, since portion of the muscle fiber is forced through the sarcolemma, which, for the time being, is supposed to assume a reticular character, at least for chemical particles, and that this liquid collects in spaces between the fibers. Slow thawing, the authors believe, causes a resorption of the exuded materials without detectable alteration of the fiber either by chemical, physical, or histological evidence. On page 314 of volume 2 of the proceedings of the congress just cited, the authors state that “It is not necessary to give detailed tables showing the analytical results (chemical) on cold-storage chickens, inasmuch as the results are in general similar to those ob- tained in the case of beef.” A little later it is said that “The figures indicate no bacterial action whatever (uniform ammoniacal nitro- gen) and no increase in proteoses (absence of marked enzyme action) up to eighteen months.” Again, it is to be regretted that the authors give none of the data on which their statements are based, since, in the present extreme paucity of amalyses of cold-stored flesh of any kind, and our lack of knowledge concerning the composition of fresh chicken flesh, as well as frozen, all information is of value. Under the caption of “Unrendered animal fats in freezer storage” it is stated that the abdominal fat of fresh chickens holds 0.20 per cent of free fatty acid; that three chickens four and one-half months old showed, respectively, 0.40, 0.40, and 0.56 per cent of free fatty acid, a practical doubling of the content of free acid, though both quantities are low. After nineteen months two samples showed, re- b Richardson and Scherubel, J. Amer. Chem. Soc., 1908, 30: 1515-1564. 5 5. spectively, 0.96 and 0.48 per cent of free fatty acid. With only two analyses from two chickens, one can not make conclusive deductions, but the indications are that Richardson obtained a rise in free fatty acid even after four months of storage. In the proceedings of the same congress Pennington * reported some of the work which Wiley and associates in January, 1908, had stated to be in progress. Much of this report was published in November, 1908, as Bulletin 115, United States Department of Agri- culture, Bureau of Chemistry, as well as other matter which will receive attention in its proper place. The investigations given in the bulletin of the histology of cold-stored chicken muscle deal with market birds only of which no history previous to storage was ob- tainable. The studies reported at the congress, however, were chiefly based upon the examination of birds of known history, killed and dressed and stored under known conditions, and examined at inter- vals of one month for a period of a year. The muscle of birds which had deteriorated at temperatures above freezing was also studied. A series of characteristic post-mortem changes in structure was observed, which differed from those prevailing in dead muscle at temperatures above freezing and which were progressive. They were more pronounced in the market fowls than in those of known history, as was to be expected, since those from the market were certainly not treated with the care before freezing that was given the experimental specimens. The changes in the former were refer- able both to bacterial growth (an invasion which occurred, doubt- less, before storage) and to enzyme action both before and during storage. In the latter the changes were due, apparently, to enzymes and to a coagulation of protein caused probably by long contact with air. The changes were evidenced by shrinkage and extreme brittleness of the fibers, by a striking intensification of the cross markings and a glassy appearance of the whole fiber, all of which might be referable to coagulation, and by a disintegration of the fiber substance resulting in a structureless mass, entangling con- nective tissue fibers and broken-down nuclei, and staining a different color from the fibers which were intact—hence, indicating a change in the chemical constitution. The thawing of the specimens for histological examination was carried on in cold air, and required at least twenty-four hours for its accomplishment, hence there was time for the absorption of exuded materials and a return to the normal if the fibers of the a Pennington, M. E., A Chemical, Bacteriological and Histological Study of Cold-Stored Poultry, Proceedings of First International Congress of Refriger- ating Industries, 1909, 2:216-260. 3 S 596 chicken muscle were capable of doing so. Such histological changes as were observed under the microscope were confirmed by coincident chemical analyses of both market chickens (see Bulletin 115) and chickens of known history stored for four months.” In both pub- lications the findings of the chemical analyses of both fresh and cold- stored chickens are fully given. The study of the nitrogenous con- stituents of the flesh includes the determination of the total amount of nitrogen present, the amount of nitrogen soluble in cold water, the Quantity of such nitrogen which is coagulable by heat, the nitrogen in the form of albumose and amino acid, and, by difference, the quan- tity of peptone nitrogen and nitrogen insoluble in water. Light and dark meat were analyzed separately. The fats were examined for the iodin, saponification and Hehner number, the acid value, ester value, and index of refraction. A general analysis of the flesh, including water, ash, intimate fat, etc., was, of course, made for all types of chickens studied. º The results of the study of the distribution of various forms of protein nitrogen, especially as illustrated by the study of chickens of known history, dry picked, cold-air chilled, and put into a “sharp’’ freezer twenty-four hours after killing, would indicate that proteolytic changes do take place, though they do not follow the usual course as observed in changes occurring in flesh at tem- peratures above freezing. For example, the protein soluble in water commonly decreases after long storage; the nitrogen in the form of protein soluble in water and coagulable by heat also decreases; the albumose may remain constant in quantity, even after many months of storage; while the peptone decreases and the amino bodies in- crease. This is especially noticeable in the white meat; the changes in the dark meat, while essentially the same, are seldom so pro- nounced and commonly approach nearer to the usual course of flesh proteolysis. The chemical analyses were made on seven lots of fresh chickens; seven lots of market storage chickens, aged 14, 17, and 24 months, respectively; and twelve lots of chickens of known history in storage at 12°–15° F. (–10° C.) for four months. In 1908 Boos” reported the analysis of drawn and undrawn fowl cold-stored for more than nine months. These birds were examined according to the methods of Brieger and of Bowmann and von Udranszky for ptomains. None were found. Skatol, indol, phenol, and cresol were looked for with negative results. Drawn and un- a Proc. Int. Cong. of Ref. Ind., 1909, 2:248. b Chemical Examination of Drawn and Undrawn Poultry Rept in Cold Storage, Thirty-ninth Annual Report of the Massachusetts State Board of Health, 1907. 597 drawn cold-stored fowls were thawed at 68°F. and kept at that tem- perature for six days. The undrawn birds kept better than the drawn. In July, 1909, a paper appeared by Emmett and Grindley,” en- titled “A Preliminary Study of the Effect of Cold Storage upon Beef and Poultry.” In this communication the authors present the results of the analyses of one lot of fresh chickens and four lots of storage chickens. Two of the latter—one drawn before storage, the other undrawn—were kept in the freezer for four months; another lot, undrawn, was kept twenty-one months; while the storage period of the remaining lot of poultry, which was drawn, was unknown. No details of preparation are given, except that the poultry was put into a storage warehouse the same day that it was killed. Since Chi- cago, where the chickens were killed, is a market in which scalded chickens prevail almost exclusively and the bird is killed by breaking the spinal column near the head and bleeding is accomplished by gashing the throat from the outside, hoping thereby to cut both jugu- lar veins, the animal heat being removed by soaking in cold Water, or finally ice water, it is fair to assume, in the absence of specific statements, that this was the method employed.” Light and dark meat were analyzed together. The nitrogen of the flesh was determined as nitrogen soluble in cold water and co- agulable by heat; noncoagulable (proteoses and peptones), and non- protein nitrogen (amino bodies). The total nitrogen soluble in water is the sum of these constituents; the total nitrogen in the meat itself, less the nitrogen soluble in water, being considered as in- soluble protein nitrogen. While the analyses of the flesh both by Pennington and by Em- mett and Grindley were for essentially the same constituents, the different methods of stating results make comparisons difficult. Emmett and Grindley do not calculate results to a water-free basis, but they do recalculate the findings in the case of the storage chick- ens to the water content of the one lot of fresh chickens examined, taking this as the original water content for all. Since the water content of the flesh of fresh fowls is quite variable,” this is a doubtful procedure for the drawing of very accurate conclusions. It has been shown (loc. cit.) that there may be a maximum variation of at least 2.2 per cent in the moisture content of light meat and of 4.2 per cent a J. Ind. Eng. Chem., 1909, 1:413. b It has been shown (Pennington, address before the American Warehouse- men’s Association, December, 1909) that of all the methods, so far studied, Cf preparing poultry for cold storage, the above procedure gave the most irreg- ular and most unsatisfactory results. c Pennington, Proc. First Int. Cong. Ref. Ind., 1909, 2:243. 598 in the dark meat, which would make a decided difference in such calculations.” - * While the methods for the study of flesh protein used by Emmett and Grindley and by Wiley and Pennington were based upon the same general plan, the latter adopted certain mechanical devices in the interest of thoroughness and speed (since enzyme action during long extraction periods must be reckoned with), such as shaking machines and centrifuges, which rendered extraction and filtration rapid and complete." In the work of the latter albumoses were separated from peptones —a separation which has given valuable information because, though Average nitrogenous constituents of chicken muscle. [Expressed as per cent of total nitrogen present.] Total ni. Sºlº: Peptone {ar Total ni-trogen in blºor ..º., |niº || Aºin? Description. gen in mose ni- §: * | acid ni- trogen. ºs|aºuedus tºge. ºf tº:é. extract. eXtract, ſerence). e Fresh chicken, mixed meat (Emmett * * ~ * and Grindley) ............. ------------ 3, 265 18.28 6.49 Ö. 673% 11. 12 Fresh chicken (7 analyses, Pennington): y- | t / Light meat -------...---------------. 3.900 24, 88 11.01 . 624 4.63 8.44 Dark meat.-------------------------- 3.570 18.05 8.04 . 558 2. 16 7.21 Stored chicken (4 months), mixed meat || - * . - (2 analyses, Emmett and Grindley) ... 2.970 16, 62 5.99 . 522 10, ()7 Stored chicken (4 months), 12 analyses, Pennington: Light meat . . . . . . . . . tº e º sº º ºs & e * * * * * * * * * 3.970 24.73 10. 77 . 733 4. 37 8, 95 Dark meat . . . . . . . . . . . . . . s = * * * * * * * * * * * 3. 640 20, 54 9.87 , 990 2, 55 7, 24 Stored chicken (21 months), mixed mcat (Emmett and Grindley) . . . . . . . . . . . . . . . 3. 356 22, 47 9.95 .894 11. 62 Stored chicken (time unknown), mixed | meat (Emmett and Grindley) . . . . . . . . . 3.433 21.62 8.91 1,165 11.53 | the albumose is likely to remain practically constant throughout long periods of storage, the peptone generally decreases markedly. A comparison of the nitrogenous constituents of the flesh of chick- ems from various sources and of various ages is rendered difficult by the differing water content of the flesh. To eliminate this factor, Penmington (loc. cit.) has expressed the quantities of the protein nitrogen cleavage products in terms of their relation to the total amount of that substance, taking the latter as unity. On such a basis the water content of the flesh is without effect, and, since no nitrogen is lost, its redistribution can be directly compared with that previously prevailing. It is of interest to compare the results ob- tained so far by the different analysts when calculated on this basis. c Tater work on 82 fresh broiling chickens gave a maximum water content of the light meat as 75,76, a minimum of 73.32, and a mean value of 74.79. For the dark meat the maximum was 75.94, the minimum 71.75, and the mean 74.84. Twenty roasting chickens gave a maximum for the light meat of 75.73, a minimum of 73.30, and a mean of 74.14. For the dark meat the maximum was 75.86, the minimum was 73.02, and the mean 74.30. d U. S. Dept. Agr., Bureau of Chemistry Bul. 115. 599 Emmett and Grindley (loc. cit.) have determined the phosphorus content of the flesh of chickens stored for four months and for one sample of unknown storage time. The results are given as soluble organic and soluble inorganic phosphorus. Unfortunately, corre- sponding analyses were not made on the fresh chicken; hence Com- parisons can not be drawn. ACTION OF LOW TEMPERATURES ON CHICKEN FAT. The work done by Richardson on the fat of chickens, kept for four months and nineteen months, respectively, has already been quoted in full (see p. 6). The fat of market cold-stored chickens was studied by Wiley and Pennington and their findings reported in Chemistry Bulletin 115. Pennington reported the analysis of the fat of chickens of known history, stored for four months, at the First International Congress of Refrigerating Industries (Proc., vol. 2, p. 252). A rise was observed in the acid value in all twelve lots examined, in some cases closely agreeing with the rise reported by Richardson (loc. cit.) and in other cases exceeding it. A decrease in the iodin number is generally found, representing a loss of unsatu- rated acids, as well as a loss in the Hehner number, which would indicate a solution of acids originally insoluble. The question of acidity in crude fat, both fresh and cold stored, has been further studied by Pennington and Hepburn,” in an effort to find chemical criteria by which aging food fat might be judged. Incidentally, among the samples of fat examined were some from cold-stored fowls of known history and carefully prepared. A rise in free fatty acid was observed which, in the same lot of chickens, tended to increase with the length of the storage period. FORMATION OF AMIMONIACAL, NITROGEN AT FREEZER TEMIIPERATURES. It will be recalled that Richardson (loc. cit.), in the brief state- ment of his work on cold-stored poultry, asserts that change during storage did not occur, because there was a uniform ammoniacal nit- rogen content. In his work on beef Richardson very properly lays great stress on the presence of loosely bound ammoniacal nitrogen, and studies in detail several of the methods for its estimation. He finally adopted boiling with magnesium oxid as the preferable course to pursue. Pennington and Greenlee,” studying flesh decomposition, repeated the work of Richardson, but without success, because it was a J. Amer. Chem. Soc., 1910, 32:568-572, b J. Amer. Chem. Soc., 1910, 32: 561-568. 600 not possible to reach a point where the loosely bound nitrogen ceased to be evolved, even though many distillations were made; and be- cause, with the most exact conditions obtainable, there was a dis- couraging discrepancy between the quantities of such nitrogen from chickens of similar though not identical history. The authors there- fore adapted the Folin method for ammoniacal nitrogen to chicken meat, with a gain in differentiation and accuracy. The study of dry-picked chickens, chilled for twenty-four hours at 32°–38° F. (0° C.—3° C.), shows that the quantity of loosely bound nitrogen in the flesh varies from 0.011 to 0.012 per cent of the fresh substance. Similar chickens, stored for one year, showed 0.019 per cent; for two years, 0.027 per cent; for two years, but in bad condi- tion, 0.036 per cent; for the same period of time but in excellent condition, 0.023 per cent. A fowl properly chilled, then kept nine days in a house refrigerator, gave 0.017 per cent of ammoniacal nitrogen. These stored fowls had been kept at from 10-15° F. (–12 to —9° C.) and were analyzed after thawing in a house refrigerator. Whether such loosely bound nitrogen is a product of bacterial growth, as is commonly held, or of enzymic activity, its formation at temperatures so far below freezing is of both scientific and prac- tical interest. BACTIERIAL CONTENT OF FIROZEN IFILESH. The bacterial content of the flesh of cold-stored poultry was not touched upon by Richardson except in the general statements al- ready quoted. Emmett and Grindley confined themselves strictly to the chemical side of the subject, hence the work of Wiley and his coadjutors is the only specific American work on the question. Stiles (Bulletin 115) established the fact that bacteria not only persisted in a viable state in the flesh of frozen poultry of known history after two years of storage, but that this resistance was common to a wide variety of species. Pennington (Bulletin 115) showed that a quanti- tative determination of the number of organisms in the flesh of cold- stored market chickens indicated the same condition, and also that while long holding in a frozen condition tends to kill a certain pro- portion of the germs, the period required for so doing is beyond that commercially practiced. And, also, by the time storage has been sufficiently long to destroy the bacteria the eating quality of the flesh is greatly lowered. - Pennington (Proceedings First International Congress of Refrig- erating Industries) also showed that the presence of a few bacteriz twenty-four hours after death, even with careful and rapid chilling, 601 could be demonstrated in the muscle of breast and thighs by the use of special quantitative methods. Hence the fowls are not sterile when they enter the freezer, though promptness, care, and cleanli- ness may reduce the number of the organisms to a minimum. EXAMINATION OF STORAGE EGGS. The study of fresh and cold-stored eggs, chemically and bacterio- logically, is practically a new field. A report by F. C. Cook (Bulle- tin 115) gives observations on five samples of stored eggs, varying in age from 3.5 to 19.6 months. The characteristic “storage” odor was noticed after 12.6 months; the separation of whites and yolks was difficult at the end of 7.5 months, the whites becoming more and more watery as time progressed. It was observed that the boiled stored eggs gained water in both white and yolk, the yolk finally containing considerably more water than when fresh. Storage eggs, analyzed after boiling hard, show an increase in the lower nitrogen bodies, proteoses, and peptones. There is also a decrease in the coagulable nitrogen and in the amino bodies. The lecithin phosphorus was observed to decrease in stored eggs after 3.5 months. . Howard and Read (Bulletin 115) observed characteristic rosette crystals in the yolk of eggs stored 12.6 months. The composition of these crystals was not determined, but the fact that they were not tyrosin was established. The bacterial content of storage eggs has been examined by Stiles (Bulletin 115). He reported a fairly numerous but varying number of organisms after three months’ storage. Then a decrease took place until about twenty months, when the sample was sterile. A number of common saprophytic species of organisms were isolated from the shorter storage samples. As a preliminary to the study of the effects of handling on the quality of eggs, Pennington * has reported the chemical composition and bacterial content of fresh eggs, whites and yolks separately, from both Leghorn and Plymouth Rock hens. The species of the organisms found in the eggs was also determined. INDUSTRIAL APPLICATION OF REFRIGERATION. - The knowledge of the application of mechanical refrigeration to the poultry industry has been, until recently, confined to compara- tively few. Those few have acquired what information they possess a J. Biol. Chem., 1910, 7: 109-132. 602 by selecting and applying practices which carried the poultry to the consumer in ‘‘good order.” But, since standards of excellence vary, the term “quality,” as used by the various packers, is variable in meaning. A close study of conditions resulting in good or bad quality, so far as decomposition is concerned, has now been instituted by the United States Department of Agriculture in co-operation with all the branches of the industry. For instance, the killing and dressing of the fowls is studied with the packer; their transportation to market is being worked out with the co-operation of the railroads of the United States; the study of the cold-storage question is facilitated by every means which the cold-storage warehousemen have at their dis- posal; and the marketing of the goods is studied in the establish- ments and with the help of commission men, jobbers, and retailers throughout the country. - Since this article endeavors to set forth the practical application of refrigeration to the handling of dressed poultry in the United States, the subject will be treated in chronological order, beginning with the slaughterhouse and the removal of animal heat by chilled air. Then will follow the discussion of the environment of the fowls during their transportation in refrigerated cars, which may take them to the cold-storage warehouse, where they will sojourn for a number of months before they reach the hands of the middlemen; or, if they are to be consumed without storage, the railroad haul will take them directly to the commission men and thence they will go to the retail merchants. The discussion of the handling of eggs will proceed according to a similar plan and will follow that on poultry. Before the days of mechanical refrigeration the shipper of dressed poultry killed and sold most of his stock in the fall and winter months, when nature could generally be depended upon to remove the animal heat. Even now the small, or conservative, packers fre- quently adhere to this old-time principle, which is most excellent when the weather conditions are just right; that is, when the air is dry and of a temperature between 30° and 35° F. (–1° and 2° C.). Unfortunately, however, such conditions can not be depended upon in so variable a climate as that of the United States. The temper- ature may suddenly rise, in which case the animal heat is not re- moved and decomposition will follow with undue haste; or it may fall below the freezing point of the flesh, when the external parts will cool too rapidly, so preventing the radiation externally of the animal heat and resulting in a rapid putrefaction of the viscera. 603 CHILLING PoulTRY-CHILL Rooms. That an equable desirable temperature may be maintained con- tinuously, the most progressive poultry dressers have now adopted an artificially cooled chill room, in which they place their poultry immediately after killing and dressing and hold it there until the temperature of the body cavity of the fowls is the same as that of the surrounding atmosphere. The construction of these rooms commonly includes a wooden lining, though cement is coming more and more into favor. Either must be kept scrupulously clean, since it completes the inner surface of a system of insulation which may be composed of cork, felt, or any other suitable material. Two chill rooms are not only far more desirable and more effica- cious in their results, but after the first cost of installation they are more economical to operate than is a single room if any quantity of fresh poultry is to be handled on successive days. The advent of freshly killed stock into a room containing partly or wholly chilled poultry means a rise in the temperature and a consequent warming up, or sweating, of the chilled portion—two conditions which are always to be avoided if possible. It is far better, therefore, to maintain one chill room between 35° and 40° F. (2° and 4° C.), allow the birds to remain in it for several hours, or until the greater part of the animal heat has been removed, and then transfer them to the second room, which is maintained below 35° F. (2° C.), preferably at about 30° F. (–1° C.), for the final chilling. In this room, too, it is advisable to do the packing. CIRCULATION OF AIR. A very desirable method of chilling is a combination of the direct and indirect systems, thereby insuring a circulation of air through- out the room and preventing the blanketing of the warm material by a failure to draw from around it the heat which it radiates; or the pipes carrying the brine may be so distributed and inclosed that a constant circulation of air is maintained and the efficiency of the chill room thereby greatly increased. Where exposed piping is placed on the side walls, which is the method most commonly used, it has been found advantageous to put fans in different parts of the room to keep the air in circulation. Temperatures taken at different levels will show a progressive rise as one goes from floor to ceiling or a decided increase in the immediate vicinity of freshly killed poultry. Hence it is desirable to place a number of fans 604 near the floor with their blades so set that the current shall be driven upward, thereby replacing the warm air which collects at the upper part of the room by the cooler air from the floor. TIME REQUIRED FOR CHILLING. In practical work twenty-four hours are generally required to remove the heat from the entire body of an undrawn fowl of ordi. Fig. 1.-Corridor showing entrance to freezer and chill room. nary size. The fact that it is removed is determined by inserting a thermometer through the vent and up the intestine as far as it will easily go, waiting a few minutes until the mercury shall have fallen, and then noting the temperature at which the column stands. If this test is applied to the largest fowl in the most unfavorable part of the room, as, for example, near the door or on the topmost layer of the rack, and the temperature of the body cavity is found satisfactory, it can safely be assumed that smaller, better-placed birds are also chilled. - . ºkuyinod. 8 upprou roj sxſ seu pue silew ºpis uo 8 undţd 8u, w oqs uroou IIſuſo ‘º ‘āſ ſſſſſſſſſſſ！！! |×|-|-，\，\！||- |×ſae:|×| --- ！！！！！！！！!！！！ ·|- |-|：|| ! |×- |- · 606 C3HILLING FOR LONG OR SHORT HAULS. It is searcely practicable to assert that the animal heat of a chicken is not removed until it has been cooled to a certain fixed temperature, because the thoroughness with which the fowl should be chilled depends largely on its destiny. If the poultry is to be consumed in the immediate neighborhood of the packing house, and if the time before consumption is to be a matter of a few days only, a temperature between 35° and 40° F. (2° and 4° C.) will gen- erally carry the goods through the market in fair order, providing, of course, the middlemen are equipped with adequate refrigera- tion, a subject which will be discussed further on in this paper. If, however, the chickens are to be transported for long distances or to a market where delays may occur, the initial chilling must be more thorough and the body temperature of such fowls should not exceed 32° F (0° C.) when they are packed. The final chill-room temperature, too, is influenced by the tem- perature of the refrigerator car if the poultry is to be so shipped. It is impossible, in refrigerator cars which are ordinarily cooled by ice, or salt and ice, to maintain a temperature as low as that of mechanically cooled chill rooms. If, therefore, poultry be loaded at a temperature much below that of the chilled car, it will sweat in transit, and reach its destination in less desirable condition than if it had left the chill room a few degrees warmer. This question will be discussed further when transportation is considered. CONTAINERS. The question of containers for dressed poultry between the pack- ing house and the retail merchants is one that has been greatly modified since the introduction of mechanical refrigeration into the industry. Formerly, large boxes, holding between 100 and 200 pounds, or more commonly, barrels holding 250 pounds at least, were used almost exclusively to carry the chickens from the killing place to the market, because the large package is more economical * and more convenient when layers of ice between the layers of birds is the source of refrigeration. ~ The heavy weight of the contents of such a package induces de- cay. Uncleanliness is also a great objection, as will be discussed later, and it has additional disadvantages. When the temperature can be depended upon for satisfactory chilling and maintenance of refrigeration, these barrels are frequently used by those who practice ice packing customs with the ice omitted; and they are 607 sometimes used by packers whose plants are equipped with me- chanical refrigeration, but usually for low-grade stock only. The prevailing method at the present time, where facilities for refrigeration are available, is to pack the chickens in small boxes holding a dozen each. If the birds are of the broiling type, they are commonly packed with the breast up, and the feet hidden (see fig. 3); if fowls or roasting chickens, they are packed two layers in a box and laid on the side (see fig. 4); while the chickens for export trade to England are “squatted,” though this is an undesirable position in that it pushes the bird into a compact mass, thereby delaying the radiation of the animal heat. The tendency is now to use smaller and smaller packages. Two Fig. 3.-Broiling chickens packed breast up. layers of chickens in a box, even in the case of fowls, are being discarded for a single layer, it being recognized that refrigeration is more perfect if flesh is not superimposed on flesh and if pres- - | 608 sure on such a tender tissue as chicken muscle is eliminated as far as possible. On this account heads are wrapped in parchment paper and turned back, where they rest against the bony structure rather than against the soft flesh of the breast or thighs. The carton Fig. 4.—Roasting chickens, side-packed. for the single chicken, or for a pair at most, is the most recent advance (see fig. 5), and is one which has a foundation on scien- tific fact that will be discussed later. - TRANSPORTATION_HOLDING FOR SHIPMENT. It is of course necessary before packing the birds in the boxes that they should be thoroughly chilled. Large packing houses, or a house of the ordinary size during the season of excess produc- tion, will ship three or four earloads a week, in which case the holding of the birds in the packing-house chill room is for a minimum time only. If, however, they must be held for several 609 days before the carload is accumulated, as is the case in a small house or in the dull season, it has been found advisable to box as soon as the stock is thoroughly chilled and then to hold at the lowest available chill-room atmosphere; or, if a freezing room is part of the packing-house equipment, to transfer the boxes to it for from twenty-four to forty-eight hours before loading in the re- frigerator car. When the freezer, between 0° and 15° F (–18° to —9° C.), is to be used for holding, the boxes should be so placed in it that the Fig. 5-Small cartons containing two chickens each. air circulates freely around each one. This is accomplished gen- erally by leaning the boxes at a sharp angle in a horizontal row rather than by placing them in a perpendicular pile, shifting each box forward or back of the median line in order to leave as much as possible of that box uncovered by its successor. This is known in the trade as “staggering” boxes, and is pictured in figure 6. 39 610 Forty-eight hours in a good freezer will very thoroughly harden birds of the ordinary size packed not more than 12 to the box, and - Fig. 6.—“Staggered” boxes. - - a number of such boxes in a refrigerator car is a valuable aid in the maintenance of an equably cold temperature. PoulTRY REFRIGERATOR CARs. The facilities of a refrigerated killing and packing house such as here discussed will avail but little in the getting of good poultry to market if it is not supplemented by a system of transportation which will maintain a constant low temperature for a sufficient length of time to carry the chilled goods to the market center. It is the aim of the refrigerator-car service to maintain such tem- peratures for such lengths of time that products which are a thousand miles or more from the point of consumption can be con- veyed there in good order. For the satisfactory transportation of dry chilled poultry it is advisable to use fine ice mixed with from 10 to 15 per cent of salt in the bunkers of the refrigerator cars the year round. If the car is built with sufficient insulation and if it is in good order—that is, with tight-fitting doors, unbroken lining, etc.—ice and salt will maintain a temperature in the middle of the car, 4 feet from the floor, of 40° F (4° C.) or under. If the car is to be filled with poultry alone, and if part of the carload has been in a freezer for forty-eight hours or more, the loading is a comparatively simple matter, because the most recently killed stock is put in the lowest layers next the bunkers, where the temperature will frequently fall to 10° F. (–12° C.). Often the air around the top layer, 4 feet from the floor, next the bunker, will have a temperature not ex- 611 ceeding 30° F. (–1° C.). The boxes which have been in the freezer are then loaded in the central part of the car and packed together as tightly as possible, serving as a source of cold where it is most needed, namely, in the middle of the car, where the refrigeration from the bunkers is least. MIXED CARS. If the car is to be loaded with a mixture of poultry and eggs, as very frequently happens, the problem is much more complicated. If ice and salt are used in the bunkers, and if the poultry and eggs go into the car well chilled, the temperature may be sufficiently low to crack the eggs. If, on the other hand, salt is not used with the ice, it becomes a difficult matter to keep the poultry sufficiently cold to carry without deterioration if the haul is a long one. If such mixed cars are to be handled, and this is oftentimes a com- mercial necessity, it is advisable to chill the poultry as thoroughly as possible, piling the boxes low in the car and against the ice bunkers. The eggs should be artificially chilled to as low a tem- perature as possible before they are shipped, and they should then be placed in the middle and upper layers of the load. Since the ice bunkers are at either end of the car, it follows that every additional foot away from them will mean a rise in tem- perature; and since there is no method of inducing artificial cir- culation in general use, by which the heavy cold air at the bottom of the car can be forced to the upper part, it follows also that every foot above the floor means a rise in temperature. The mistake is frequently made of packing goods too high in a refrigerator car. Where great efficiency is necessary, as in the handling of poultry, the height of the load should be not more than 4 feet. The railroads have established icing stations where the cars are inspected and iced as conditions demand or as the instructions of the shipper specify. INSULATION OF CARS. The temperature throughout long hauls and in different parts of the car has been studied by means of thermographs. Great varia- tions are observed, due, of course, to the construction of the car, the atmospheric temperature, and the temperature of the goods being carried. r The refrigerator cars used by the various railroads, or even by - the same road, differ chiefly in the degree of insulation furnished. Thus the cars may vary in efficiency because of lighter construction and insulation or because of a variation in the insulating material itself. The tendency on the part of the railroads at the present 3.9% 612 time is to increase insulation. Cars are built more heavily, and much greater care is given to the selection and amount of the in- sulating material. There is considerable variation, also, in the con- struction of the compartments at the ends of the car for holding . the ice, or the ice and salt, upon which refrigeration depends. These “ice bunkers” are built with the hope that their construc- tion will produce some circulation of the cold air in the loaded car. At the present time this is one of the problems at which the rail- roads are diligently working, and there are numbers of types of experimental cars now being tried, all having this object in view. The efficiency of a car is affected also by its ability to withstand the usual wear and tear of traffic. Frequently doors are jarred, rendering the insulation about them imperfect; joints crack, or the shipper, to prevent his load from shifting, may drive heavy Spikes into the walls of the car, thereby doing great damage to the in- sulation. THERMOGRAPH RECORDS, Curves are reproduced (see fig. 7) to show the variation in tem- perature in a single car which had suffered hard usage and which was very badly insulated about the doors. It was iced for twenty- four hours before loading with finely chopped ice mixed with 10 per cent of salt, and loaded in the center with eggs which had been chilled before shipping, while at the bunker ends were boxes of chilled poultry. - t Figure 7A shows the temperature record of the air of the car around the upper layer of poultry boxes next to the eggs, which oc- cupied about the width of the door space in the middle of the car. It will be observed that the temperatures here varied between 45° and 50° F. (7° and 10° C.), and that nearly nine hours.were required before the minimum temperature was reached. Figure 7B shows the car temperature in the upper layer of boxes at the bunker ends. Here the temperature varied from 25° to 35° F. (–4° to 2° C.), with generally the maintenance of a temperature less than 30° F. (—1° C.). Figure 7C shows the temperature maintained on the floor of the car next to the ice bunker, and here the general aver- age would lie between 10° and 20° F (–12° and —7° C.), while the maximum is not over 25° F (−4° C.). * The type of car now prevailing, if it is in good condition, will maintain a temperature of less than 40° F. (4° C.) opposite the doors and not more than 4 feet above the floor, provided the re- frigerant be fine ice mixed with 10 or 15 per cent of salt, and the - 3. EE F. - - FEEEEEE ====== re-cº-º-E B. Upper layer of boxes next to ice bunker. C. Floor of car next to ice bunker. Fig. 7 –Temperature records in three parts of a single car with imperfect insulation. 1-2. Cooling of poultry in packing house chill room. 2-3. Haul - 3–4. Unloading car at destination showing drop in temperature because car - door was closed during dinner hour. - 614 load has been thoroughly chilled before it is shipped. This record is constantly made during hot summer weather. During the winter time the temperatures, under the same conditions, are commonly below 35° F (2° C.) and are often between 28° and 30° F. (–2° and –1° C.). It will be seen from these statements concerning the temper- atures maintained in transit that, as previously indicated, the packer must suit his chilling to a certain extent at least to the next step in the handling of his goods. This is well illustrated by figure 8, which represents the temperature history of the dressing and shipping of a carload of chickens from the packing house to the Fig. 8–Temperature record of preparation and shipment of a garload of dressed poultry. 1. First chill room, 1a-2. Second chill room. 3. Packing room and to car. 3–4. Haul market during summer weather, when, for at least a portion of the day, the atmospheric temperature was between 85° and 95° F (30° and 35° C.). - - As indicated in figure 8 between 1 and 2 on the curve, the fowls were in chill rooms, the first maintaining the temperature shown between 1 and 1a for a period of six hours, the second those indi- cated from 1a to 2 for a period of twelve hours. From 2 to 3 the birds were in the packing room, where the temperature varied from 23° to 25° F (–5° to —4° C.). They were then placed in a car which had been chilled for twenty-four hours with fine ice and 10 per cent of salt. From 4 to 5 on the chart represents the tem- peratures during a 48-hour haul. It will be observed that at the end of the first day the temper- ature was rising markedly, reaching a maximum of 41° F (5° C.). At this point the icing station was reached, and, according to the instructions issued with the car, it was reiced and salted, where- 615 upon the temperature within a space of five hours dropped to 34° F. (1° C.), and this was maintained uniformly to the end of the haul. No fault could be found with the temperatures in this car for a , two-day haul of chilled poultry. However, when the car arrived at its destination, and the boxes were opened, the poultry had so much moisture condensed on the surface that it was distinctly wet, a condition known in the industry as “sweating.” This condition is undesirable in that it induces the growth of mold and hastens de- cay, unless the surfaces of the birds are promptly dried. It was caused by the fact that there was a difference of 17° F. (9° C.) be- tween the temperature at which the birds left the packing house and the highest temperature reached during the haul. It would have been better in this case had the birds left the chill room with a temperature of 32° F. (0° C.). - REFRIGERATION IN THE MARIKET. In the handling of poultry the facilities of the middlemen and retailers, for holding the goods in a chilled condition, are of great importance. Artificial refrigeration in the packing house may give excellent chilling facilities; the railroad refrigerator car may main- tain the necessary low temperature throughout the haul, and yet, between the arrival of the poultry at the market and its final sale to the consumer inadequate refrigeration may render the previous good work valueless. - Having chilled or frozen the poultry the low temperature should be constantly maintained until the product is consumed. Fluctuat- ing temperatures cause a condensation of moisture and a consequent activation of bacteria and enzyms, with resulting decomposition. Such being the case, cold storage warehouses and large dealers in poultry have found it almost a necessity to have railroad trackage at their own receiving platforms, thereby eliminating the wagon haul and an extra handling of the packages. If wagons must be used to transfer the goods from the car to its next destination, the load should be covered with canvas or otherwise insulated as perfectly as possible. The most efficient method for the wholesaler to adopt for carrying large quantities of dry-packed poultry between receipt and dis. bursement is the use of a mechanically refrigerated chill room of the same type as that of the packing house, and maintaining tem- peratures below 40° F (4° C.). If frozen stock is to be handled, 616 a room maintaining a temperature which is below 15° F (–9° C.) should also be available. - The recognized need and advantage of refrigeration for both large and small dealers in dressed poultry has led establishments which produce large quantities of a low temperature refrigerant to supply it through underground pipes, at definite cost, to dealers in perishable goods, thereby saving them the maintenance of refrig- erating machinery. A considerable number of city blocks are fre- 617 quently traversed by these pipes, and large markets as well as individual shops are thus supplied with the refrigeration required for the especial kind of produce carried. Not only are insulated rooms so chilled, but holders of market stalls may have boxes me- chanically cooled for holding supplies and show cases for the dis- play of goods. Figure 9 shows a market house in which mechan- ically refrigerated boxes have entirely replaced ice boxes, and which provides chilled show cases. The temperature of a first-class ice box is, ordinarily, about 45° F. (7° C.). Ice and salt, with a system which enables the brine to circulate, gives temperatures approximating the chill room and can be advantageously used by the middlemen if mechanical re- frigeration can not be obtained or when ice is cheap. The installation of mechanical refrigeration of one type or an- other is growing rapidly among the more progressive middlemen. The retailer still depends almost exclusively on an ice box for the keeping of his stock. Many retail merchants doing a large busi- ness are adopting the practice of obtaining fresh supplies daily from their wholesaler’s chill room, especially if they deal in dry- packed poultry. Those who still cling to the old methods of ice packing generally use zinc-lined, drained boxes in which poultry and fine ice are mixed together. When it is recalled that, including the time consumed in the haul, the time required by the commission man to dispose of his stock, the time that the retailer keeps his goods before all are sold, and the day or two that the housewife may keep the fowls before cooking them, about three weeks elapse between the date of killing and the time of consumption, it will be recognized that every step in the handling of dressed poultry demands perfection of detail if the product in our markets is to be good. About three weeks is the amount of time commonly needed for the marketing of chilled poultry in the large cities of the East, North, and Far West. In the Middle West, which is nearer the sources of abundant production, the marketing time is shorter; and in the South climatic conditions and a general lack of refrig- erating facilities necessitate prompt movement of perishable stuff of all kinds. FROZEN POULTRY. Freezing poultry during the season of excess production, and holding it in that condition until the season of shortage arrives, has become a trade practice. in the United States. Goods so kept are commonly called “cold-stored,’’ though it is a difficult matter 618 to draw a sharp distinction between produce which is held for weeks in a chill room, yet is accepted on the market as “fresh,” and that which is frozen for transportation or marketing purposes and held, possibly for several weeks, in a frozen state, and goes, therefore, as “storage.’’ - Unfortunately, “cold stored” poultry has too frequently been synonymous with market stocks, held for sale in an unfrozen con- dition until the last minute, then put into the freezer in undesirable packages and already showing evidences of decomposition. Usually the owner intends to remove and sell such goods within a few days. Too often it is weeks and months before they reach the market. Deterioration has progressed while in the frozen state—slowly, it is true, but nevertheless unmistakably—and decomposition hastens after thawing. Hence the consumer gets a low-grade article and the reputation of all cold-stored produce suffers. The blame for such practices is often to be laid at the door of the commission man or the retailer. The packer who prepares goods for storage may be careful to see that the products enter the freezer in good condition. Not only that, but he generally grades more carefully when goods are to be held for a length of time in a frozen condition than when they are to go on the market for immediate consumption. It is very desirable that the poultry which is to be put in cold storage should be dry picked and dry chilled. Poultry which has been cooled in water shows blistered areas and an unsightly drying out of the skin after comparatively short periods of storage, while the scalded fowls have not only unsightly skins but a deepening of the color over legs and thighs which is very undesirable. It has been observed by the more experienced of the members of the in- dustry, and confirmed by scientific investigation also, that scalded poultry does not keep as well as that which is dry picked; neither does the water-cooled product keep as well as that which has been air chilled. - Larger packing houses at the present time aim to have not only a chill room, such as has been discussed but also a room maintaining a temperature below 0° F (–18° C.). In this room the chilled birds in boxes are kept until hard frozen. They may be carried by the packer hard frozen at 10° to 15° F. (–12° to —9° C.) until sold, or they may be shipped immediately after freezing to a ware- house which is in proximity to their final market. The packer who is not supplied with a freezer ships his carefully graded and boxed stock in a refrigerator car, with every precaution against bad treatment, to a cold-storage warehouse, where the birds 619 are frozen and where they are kept until marketed. It is the aim of the packer or the warehouseman to freeze the birds as promptly as possible, since upon this, in a considerable measure, depends the retention of their clear color and fresh appearance. Hence it is not unusual now to find warehouses which maintain rooms 10° below zero (–23° C.), into which the stock is put for two or three days or until completely frozen. It is then transferred to a room having a temperature of about 10° F. (–12° C.) where it is carried. In order to freeze quickly boxes must not be piled tightly one upon another, and it is desirable to keep them as near the floor of the freezer as possible. Hence they are tilted one against the other, resting on the floor of the room in long rows, boxes being pushed alternately from side to side of a center line so that the maximum portion of each is exposed freely to the cold air of the room, as shown in figure 6. Since quick freezing is so important an item, it can be readily seen that large containers, such as barrels, are undesirable for long storage. It is advisable also to exclude air from the birds after they are chilled; hence tight packages are coming more and more into use. To protect the birds from rubbing against one another in the box, or freezing to a solid mass, high-grade stock generally shows each fowl wrapped separately in parchment paper. If the packer possesses a suitable freezer, he may prefer to freeze his storage stocks, in which case, when shipping, he will find it necessary to salt the ice for refrigerating the car very heavily and to see that it is thoroughly chilled before loading. Boxes of frozen poultry are packed tightly, and the load may, for additional safety, be covered with a heavy canvas to protect it from the warmer air of the upper part of the car. Such a precaution is seldom necessary except in very warm weather. The haul from the railroad car to the warehouse, if platform facilities are not available, should be performed with all the expedi- tion possible and with as much insulation as the wagons permit. Much of the poultry which lacks “bloom’’—that is, the clear, fresh, bright quality of the skin—does so because of the several superficial thawings and refreezings to which it is subjected during transpor- tation and marketing. It is a comparatively simple matter to keep birds in good condi- tion from one season of production to the next in a well-constructed cold-storage warehouse, provided those birds are received at the warehouse properly dressed, chilled, and packed, and with such promptness that decomposition has not obtained even a slight foot- hold. Under such conditions the responsibility of the warehouse is 620 the maintenance of cleanliness and a constant temperature which is not above 15° F. (–9° C.), and which preferably should be nearer 10° F. (–12° C.). If, on the other hand, the poultry is not properly prepared for storage, or if decomposition has begun (even though it may be scarcely perceptible to any of the senses), it is impossible with the lowest temperature obtainable to prevent deterioration. Poultry, even in the best of condition, is not improved by being kept frozen for any length of time. About the sixth month of car- rying a careful observer, judging by the taste alone, can tell the difference between frozen poultry and that which is freshly killed. Up to nine months, however, this difference is so slight that it is of scarcely more than scientific interest. But after nine months, though undoubtedly the flesh is wholesome and nutritious, there is a loss in flavor the degree of which is dependent upon the length of time for which the storage has been continued: The thawing of the frozen chicken preparatory to its use as food is a matter of great importance if the good qualities of the fowl are to be preserved. It was formerly customary to thaw birds by throw- ing them into cold water. This method, on a commercial scale, is practically certain to result in thawing in dirty water, thereby so contaminating the flesh that decomposition proceeds very rapidly. It is also deleterious, in that it extracts a considerable part of the flavor of the flesh. This being the first attribute of the fresh chicken to be lost by cold storage is the one which should be most carefully guarded. To preserve it, as well as the appearance of the fowl, thawing should be accomplished by hanging the bird in cool air, if possible at the temperature of an ordinary ice refrigerator for twenty-four hours. This time is sufficient to thaw a bird of the usual size. A slightly longer period may be required for large roasting chickens. There should also be some circulation of air, that the moisture which settles on the skin of the chicken may evaporate. So thawed, a bird well prepared and stored for a rea- sonable length of time—that is, from one season of production until the next as a maximum—will have a clear, fresh color in the skin, which will be soft in texture, slipping easily from the muscles be- neath it. The flesh of breast and thighs may be very slightly deeper in color than in the fresh specimen, but so little that the change is negligible from a practical viewpoint. The fat is generally a little deeper in color and may have a slight taste and odor of rancidity. The practice of thawing poultry for selling and then, in event of a lagging market, returning the thawed stock to the freezer for a second wait there is one of the unfortunate habits of the trade, but, happily, it is decreasing among the more careful. Refreezing is 621 never a success, and the loss in quality after the second thawing has led to a strong disapproval of the practice by all who are acquainted with the results. While the refreezing of poultry thawed in air is decidedly deleterious, that which is thawed in water and refrozen is in a much worse condition. The interval between the thawing of cold-stored poultry and its receipt by the housewife can not be too short in the interests of good, wholesome food. It is far preferable to deliver the goods to the consumer hard frozen, permitting the thawing to take place in the house ice box. If the poultry is frozen by the packer and maintained in frozen condition until received by the consumer, it will need to be “ripened” for several days in the ice box before eating, else it will have the flat flavor so disappointing to the epi- cure. If, on the other hand, it is sent chilled to the warehouse to be frozen, a trip requiring in many cases several days, it will be found of good eating quality after the twenty-four hours required for the ice-box thawing. ~. THE REFRIGERATION OF EGGS. they, probably more than any other food staple, are dependent upon seasons and conditions for production. In the temperate zone the sequence of seasons results in the production of a large proportion of the whole year’s lay during the spring months. In the winter months the production, as compared with consumption or demand, is extremely small. Hence the necessity of preserving eggs from April until December in a wholesome condition, retaining as much as possible of their freshness of flavor. & Of all the various methods for the preservation of eggs, cold is, so far, the best. Its application to the keeping of eggs, however, must be along definite lines. As has been stated when discussing the application of refrigeration to the marketing of poultry, it is efficacious in maintaining high quality for a reasonable period of time if the eggs are put into the cold room in prime condition. Cold does not make them better, whether of low or of high grade, and when deterioration has already begun cold does not retard the process to the extent that it does when the eggs are fresh. The use of cold, therefore, as a preservative of eggs depends very largely for its success upon the condition of the goods when they come to the cooling room or the storage warehouse. The range of tempera- tures used in the handling of eggs, however, is very small by com- parison with that commonly used in handling poultry, and tempera- 622 tures low enough to freeze the egg, even superficially, are dis- astrous. Industrial practices in handling poultry have so progressed that artificial refrigeration is of wider application and of greater im- portance to both the consumer and the trade when used to preserve freshness during the routine of marketing than when used to carry goods for long periods in a frozen condition. As applied to eggs, however, the reverse is true from the viewpoint of industrial prac- tice. Artificial refrigeration is more extensively used when eggs are to be kept for the season of shortage than for the preservation of high quality and the prevention of deterioration during routine marketing. Happily for the consumer, however, the industry is be- ginning to recognize the value and importance of keeping eggs cold throughout their entire journey from the hen to the table; happily, too, for the industry, since the application of practical chilling methods will in a large measure wipe out the losses which are now so prevalent. The great egg-producing section of the United States is coinci- dent with the corn-raising territory; that is, it comprises the Central States and the entire Mississippi Valley, with the exception of its extreme northerly and southerly portions. The numerous small farms and suburban producers in the Middle Eastern and the North- eastern States ship their output to near-by cities generally for prompt consumption, storing only when the supply is exceptionally large, and then only when weather conditions are favorable to the good keeping of the product during its transportation to the ware- house. Hence the small farmer of the East has concerned himself chiefly with production, the question of handling being scarcely considered, and the methods in vogue have not been essentially changed in many years. On the other hand, the producing section of the West, far from its market, busy with large farming opera- tions, has allowed its chickens to breed and feed as best they could except for the few winter months, when some care must be given them. The packer, however, has centralized the output of eggs, just as he has the output of poultry, and has developed methods for handling which will carry his product to market in good condition, even though the haul is a week or more in duration. It has been shown that the need for artificial refrigeration in the handling of poultry begins as soon as the bird is killed and picked; that is, in the packing house. Eggs also need refrigeration in every phase of handling, but at present it is not available until they are received by the packer. The farmer, the country storekeeper, and the small shipper have no facilities for cooling the eggs. They are 623 * careless, moreover, in that they do not collect the eggs with sufficient frequency, and, having gathered and concentrated them, they per- mit them to stand for days in hot sheds or rooms. Hence, during the hot weather the losses due to incubation are enormous, and general deterioration with loss of flavor is almost universal. The packers themselves are but slowly grasping the fact that eggs, during the hot months, demand refrigeration for the preservation of freshness quite as much as poultry. Too many packing houses are still with- out facilities for chilling eggs as promptly, completely, and continu- ously as dressed poultry is chilled. When the packer receives the eggs at the packing house in a fresh condition, puts them immedi- ately into a chill room which is 38° to 40° F. (3° to 4° C.), grades and packs them at that temperature, and ships in a refrigerated car, deterioration is reduced to the minimum that our present knowledge of egg handling affords. Thorough chilling of the usual package of 30 dozen eggs in paste- board “fillers” containing 3 dozen each, packed in a case made of an odorless wood, is not accomplished easily nor speedily. The cases should be stacked with air spaces of at least an inch around each, and from twenty-four to seventy-two hours will be required for chilling, depending upon the size of the room and the number of boxes. . & The condensation of moisture on the shell of an egg, due to its passage from a lower to a higher temperature, is quite as disastrous to its good keeping as it is to that of dressed poultry. Hence, until the egg reaches the cold-storage warehouse it is advisable to main- tain a temperature of 40° F. (4° C.), since this is more readily ap- proximated in refrigerator cars, commission houses, refrigerators, etc., than is a lower temperature. Large egg dealers are now providing not only chill rooms for short holdings, but a room as near 40° F. (4° C.) as possible for the candling and sorting of the eggs. The more progressive men at the receiving points are transferring eggs from the freight stations to their establishments with all the expedition, and care that is given dressed poultry, especially during the latter part of the season of excess production, when prices are suitable for storage but quality is apt to be low because of warm weather.’ Already the packers who have installed refrigeration for eggs, who are grading carefully in refrigerated rooms, shipping in re- frigerated cars to jobbers with refrigerated receiving rooms, are setting a new standard in the markets. Formerly eggs were graded very largely by the locality from which they came, those nearest to the market being generally accepted as freshest, while eggs from 624 the South were graded lower merely from the name on the end of the box. Receivers are learning, however, that a good flock of hens supplemented by good handling, in Virginia or Tennessee, means just as good eggs in New York as when they are sent from northern Illinois or from Michigan; and careless handling in Pennsylvania or New Jersey results in just as many rots, spots, and bad-flavored stocks as come from more distant points where care and refrigera- tion preserve quality. * The problem of getting eggs to the consumer in the hot season in good condition is a proposition which can not be solved by refrigera- tion alone, yet it is one in which refrigeration plays a part second only to the education of the farmer and that of the country store- keeper in determining the quality of eggs. Every packer who in- stalls refrigeration becomes a center of improvement in his com- munity, since he urges better handling prior to his receipt of the eggs, knowing that his chilling system will take care of them after- wards until they reach the market. Such tendencies are already launched in the egg industry. Within the next few years it is probable that rapid advances will be made in the conservation of this most important food, not only in greater production, but, what amounts to the same thing, the saving and making available in a wholesome condition of a large proportion of what is at present one of the most extravagant wastes of a people who have never had to be very careful of their food supply. f It has already been stated that, while refrigeration in the broad sense has but recently played a widespread part in the marketing of eggs, it has been used far more generally for the preservation of eggs until the season of shortage. The early spring eggs, after danger from frosting is over, are considered most desirable for long storage. Whether this is due to an inherent condition of the egg, referable to the physical state of the her, or to weather condi- tions which are favorable to egg preservation at that season, scien- tific research will have to decide. The fact remains that the de- sirable storage stocks are those which are put early into the egg- storage rooms, and it is these which can be held longest. According to trade practices, eggs are graded during the early part of the laying period by size and cleanliness, packed into a rather heavier filler than is used for current consumption, and stored in odorless wood boxes, 30 dozen to a box, at temperatures ranging from 28° to 32° F. (–2° to 0° C.), depending upon the locality and the preference of the owner. Later in the season grad- ing is dependent upon the appearance of the egg before the candle, evidences of incubation excluding it from storage. It is at this 625 period, when the quality is going down and the storage space is still unfilled, that great care must be exercised in selecting eggs for long keeping. At best, it is the custom to remove the later eggs from storage when the first demand in the autumn arises, and in spite of careful storage conditions deterioration will be found to have made more headway in them than in the earlier lots. Hence, very careful candling must precede their entrance to the market. The questions of temperature and humidity and cleanliness are of great importance in the successful cold storage of eggs. The tem- perature must not permit freezing of even the most superficial kind, yet the colder the eggs can be kept without congelation the better. fresh eggs which are thick bodied, as laid by well-fed hens, can be held advantageously at 28° F. (–2° C.); on the other hand, thin eggs, or those which have begun to deteriorate, may require 32° F. (0° C.) for safety. It is scarcely necessary to say that the latter will not keep as long as the former. A constant temperature within small limits in long storage is an absolute necessity. The majority of warehouses permit a maximum fluctuation of not more than 4° F. (2° C.) after the stock has ceased coming in. Some maintain even greater exactness than 4°. Humidity in egg keeping is a subject which is much in need of close scientific investigation. It would seem, from the experience of the industry, that the relative humidity of the atmosphere desired is variable and depends to a certain extent, at least, upon the con- struction of the storage room, the quantity of eggs stored, and the environment in general. Where refrigeration is by brine pipes only, and rooms are well filled, it is generally too moist rather than too dry for the best results; but, on the other hand, when a dry, cooled air system supplements the brine pipes, or where this is the exclusive source of refrigeration, a drying out of the contents of the egg must be carefully watched. In practice the growth of a fine, white mold on the eggshell is a good indicator of moisture conditions. This mold does not penetrate the shell; it is snow white, woolly, very delicate, and is removed by the slightest touch. The degree of humidity which permits a very slight growth of this fungus is a desirable one for egg preserva- tion. A luxuriance of growth means too much moisture. A lack of it is very apt to indicate an undue drying out of the contents of the shell.” Each warehouse storing eggs is a law unto itself, and must continue so until careful scientific studies of egg keeping under - a This fungus is being studied at the present time in the Food Research Laboratory, Bureau of Chemistry. 40 refrigeration have correlated such factors as temperature, moisture, and fresh air. --- Eggs absorb odors. Therefore, every effort is made to keep the egg-storage rooms free from them. No other commodity should be put into the same room, and in the offseason many warehouses that make a specialty of egg storage let the rooms lie idle rather than risk the absorption of foreign odors which might, later, contaminate the eggs. A plentiful coating of lime over wooden surfaces, freshly applied before the eggs are received, is the most common method of keeping walls and floors odorless. The length of time that eggs can be kept in cold storage depends very largely upon their condition when they enter it. As has been stated, eggs laid early in the season during cool weather keep best. Carefully graded, packed, and transported, such eggs are good food at the end of nine months. It is likely that they will not soft boil or poach with entire satisfaction at the expiration of that period, but for all the other methods of cooking they are available. If the eggs are of strictly first quality when they enter storage they will soft boil after six or seven months and compare satisfactorily with the “strictly fresh” eggs of the market. Indeed, when the lay falls off in the late summer and autumn, and farmers begin to hold eggs for high prices, good stored eggs from early lots are to be pre- ferred to the average market offerings. This is also true of ship- ments to market in very hot weather, when incubation is observed in almost every egg. At such times the jobber who supplies a fastidious trade may be driven to draw upon his storage stocks for satisfactory supplies. Yet with the education of the farmer in the care of the eggs produced and in the necessity for prompt sales, with refrigeration in the packing houses and refrigeration in transit and during marketing, it is merely a question of time and the ex- tension of these new methods until the bad reputation of the “July egg’’ will be a thing of the past. SCIENTIFIC IDATA APPLIED TO THE INDUSTRIAL USE OF REFRIGERATION. One after another the great industries of the world are coming to depend upon scientific methods for solving practical problems; one after another they are establishing laboratories and experi- mental plants for their own advancement. No industry can afford to ignore or slight any honest scientific research in the field of its endeavor, be the result, at first sight, laudatory or condemnatory 627 of its practices. It is upon the basis of scientific research, frequently made without any idea of its practical application, that the greatest technical advances of the age have been founded. So it must be with the refrigeration of foodstuffs. For twenty- five years the industry has struggled to achieve results, advancing by the aid of individual industrial experience only. The workers, naturally, have been men unskilled in close and accurate observa- tions and untrained in connecting cause and effect in so complicated a problem. That they have reached their present degree of skill is greatly to their credit. That great benefit, not only to the industry but to the consumer, does accrue by attacking the problems of refrigeration of foods from a scientific view point is abundantly illustrated in the change. in the handling of fruits, resulting in practically a revolution in the market product, brought about by the pomologists of the United States Department of Agriculture. Results for which the industry could find no cause were explained. The remedy, then became a comparatively simple matter. Practices which had the confidence of all were shown to be founded on errors of fact and were pro- ducers of unsuspected evils. They were promptly discontinued. With such guidance the handling and storage of vast quantities of fruit, bringing it within reach of all the people as in no other coun- try outside the tropics, has progressed in the United States until it may well be considered a model for other industries. Such scientific investigations of the chemistry, bacteriology, and structure of refrigerated poultry as have been reviewed in the open- ing section of this paper are laying the foundation for betterments in the handling of poultry and eggs under refrigeration, just as the foundations were laid in the laboratory, with microscope and test tube, for the assistance of the fruit investigators. As in the study of the handling of fruit, the United States. Department of Agriculture is taking an active part in the study of the handling of poultry and eggs, as influenced not only by refrigeration but by every phase of routine to which the produce is subjected. From the time the fowl is ready for killing, or the egg laid, until it reaches the consumer, it becomes an object of exact scientific investigation. Such a problem must of necessity require years of research, and results can not be expected to come quickly, especially when storage in a frozen condition is to be studied. It has been observed that the industrial practices which give un- desirable results in the course of the usual marketing of fowls are not only undesirable when those fowls are to be stored in a frozen condition, but the bad effects then are even more pronounced. Im- 40+ 628 provements in the handling of poultry for prompt consumption are likewise improvements if long storage is anticipated. On the whole, extra care and accuracy must be observed in the prestorage treat- ment if the best storage results are to be obtained. For example, an incomplete removal of the blood of the chicken when it is killed results in a reduced stability of the flesh, as well as an undesirable appearance of skin and muscle. Even in prompt marketing the deterioration of a fowl incompletely bled is to the detriment of its value and flavor as food. When frozen, no matter how low the temperature nor how perfect the condition of the stor- age warehouse, its discoloration increases and the time of its good keeping, so far as flavor and appearance go, is reduced as compared with its well-bled fellows. Hence the bleeding of a fowl is a matter of greater importance than might appear at first sight. An anatom- ical study of the blood vessels of the neck and head of the domestic fowl has already been made, and on the basis of this information a method of cutting to bleed has been recommended.” At least 30 per cent of all the chickens prepared for market, both for storage and for prompt consumption, are incompletely bled. Their value is reduced from 2 to 5 cents per pound thereby. Their keeping time is lowered to such an extent that it has been deemed advisable to make an accurate study of the matter, shipping under various conditions for long and short distances, marketing according to the customs of various dealers, storing in a frozen state, and mar- keting the frozen as well as the unfrozen birds. Such an investiga- tion is already under way in the United States Department of Ag- riculture. That there may be definite criteria for the gauging of the rate of decomposition, such methods as that of Folin for the estimation of the ammoniacal nitrogen, and that for the determination of the acidity of crude fat (see p. 12) have been adapted to the solving of the problems in hand. By the use of such methods gradations of quality are not dependent upon the usual inspection, which con- sists of the evidence of certain senses only, but are reduced to an impersonal accuracy. * The subject of refrigeration has a direct bearing on the study of the comparative merits of removing the animal heat from poultry by cold water and ice or by dry, cold air; and of maintaining the skins of the birds in a dry condition, or of carrying them in cracked ice throughout their marketing. The water cooling and ice packing, a Pennington and Betts, How to Kill and Bleed Market Poultry, U. S. Dept. Agr., Bureau of Chemistry, Circular No. 61. 629, keeping as it does the skins of the birds always wet, enables the bacteria, which are universally present, to multiply and penetrate the skin or any abrasion with but slight hindrance, since the tem- perature maintained by cracked ice, when moisture is so plentiful, is not very efficient in inhibiting bacterial growth; and bacterial growth in flesh means decomposition of some kind, too frequently undesirable. A bacteriological study of skins of chickens chilled in dry air and in water and ice shows a marked preponderance of organisms in the latter after even a short keeping time,” as market- ing practices go. In accordance with the fact that, for keeping, flesh should be as nearly sterile as possible, chemical analyses of air-chilled and water-chilled chickens show that the former change more slowly. - As has been stated previously (p. 12), the development of acidity in the fat is a delicate indication of the aging of flesh and one that can be observed long before the senses can detect definite alteration. Applying this test to the body fat of chickens chilled in the two ways gives results as follows:" History of sample. *i. History of sample. *i. Broilers, air-chilled, 48 hours old ......... 0.95 || Broilers, water-chilled, ice-packed, 48 Same lot after 4 days, at 32°F. . . . . . . . . . . J 2. 10 hours old ------------------------------- 0.88 Same lot after 12 days, at 32° F - - - - - - - - - .. 4.74 || Same lot, 4 days in ice. ------------------- 4. 57 Fowl, air-chilled, 8 days at 32° F - . . . . . . . . 1.65 #| Same lot, 7 days in ice......: - - - - - - - - - - - 4.71 Same lot, 12 days, at 32°F. . . . . . . . . . . . . . . . 2.41 || Fowl, water-chilled, j. 8 days...} 8.55 Fowl, kept at 32°F. for 3 days. . . . . . . . . . . . .80 || Same lot, 10 days in cracked ice........-- 8.86 Same lot, kept at 32° F. for 6 days........ 1.41 || Fowl, kept in ice 3 days. . . . . ............. 2. 20 Same lot, kept in ice 6 days........... ... 2. 70 Such results indicate very plainly why it is possible to maintain high quality for longer periods when cold-air chilling is used than when water is used for the same purpose. This is a prac- tical problem for the scientific investigator and one of the utmost importance from the view point of fresh, wholesome food. \ If freezer storage is to be applied for long preservation it is the custom of the more progressive packers to air-chill the stock (see p. 30), though the more conservative men, or those not equipped for air chilling, habitually store large quantities of water-chilled poul- try. Within a few months such poultry can be identified by small, dry, Scaly areas, chiefly on breast and thighs, and by a loss of the color and translucency characteristic of fresh birds which have not a Unpublished results, Food Research Laboratory, Bureau of Chemistry, U. S. Dept. Agr. b Pennington and Hepburn, loc. cit. 630 been water-soaked. After thawing, whether in water or air, the flesh is not so firm nor the color so good as in the case of the air- chilled poultry. If water-chilling poultry is detrimental to its good keeping, it can readily be seen that the custom of scalding poultry, which prevails in so many sections, must be even worse. Water-soaking the skin of a chicken destroys its histological integrity by an endosmotic bursting of cell walls and lowers its resistance to bacterial invasion by diluting the contents of the cells. The skin of a chicken chilled in water contains at least 18 per cent more moisture than when air chilled; hence the blisters which form after freezing the water- chilled fowls. Scalding the chicken for the removal of the feathers necessarily alters the structure of the skin far more than mere soak- ing. It reduces its protective properties, as far as bacteria are con- cerned, to almost nothing. Undoubtedly, too, its deleterious action is even deeper seated, since the keeping time of a scalded chicken is reduced to a very low figure, comparatively. The nature of this deeper action is now under investigation. A study of the behavior of dry-picked and scalded fowls after freezer storageº shows that the scalded specimens vary greatly in condition, even after three months’ holding. Loss of color, texture, flavor, and general good quality is more rapid in scalded than in dry-picked chickens. If any delay occurs before storage, or any error in handling is made, the scalded birds show the effect very soon, even if hard frozen. Incipient decomposition, though retarded in a frozen scalded fowl, is not checked to the same extent as in the dry picked. Indeed, under the same disadvantageous conditions deterioration will have obtained a good foothold in the scalded stock before it has made any headway with the dry picked. On entering the freezer a scalded bird may show no signs of active decomposition, yet after six or nine months a distinct greening of the skin may be observed, and, while quick thawing may be ac- complished without the appearance of an odor of putrefaction, yet it does come within a few hours and then increases with rapidity. While discussing the boxing of chilled poultry (p. 21) the state- . ment was made that the most recent advance in this respect lay in the growing use of a carton for a single chicken, or, at most, a pair. Experimentation in this line was begun more than three years ago by the United States Department of Agriculture, using a paraffined carton such as is commonly seen in the cracker trade, as well as a a Pennington, address before American Warehousemen’s Association, Decem- ber, 1909. 631 fairly tight tin box. It has been commonly held by the industry that fresh air is needed in the packages of frozen poultry if long keeping is desired; hence boxes have been far from tight. Experimentation, on the other hand, has shown that flavor, appearance, texture, and all-around quality have been enhanced by storage in a tin container, or even in a pasteboard carton,” from which air is excluded. A number of these experiments have been made,” using chickens dressed in various ways. The analysis of the flesh and a record of the general condition of the birds so packed, as compared with the usual box pack, are now in course of compilation. Such analyses—bacterial, chemical, and histological—as were re- viewed in the first chapter of this paper have been of great service in studying the comparative advantages of various methods of preparation of poultry for either the market or the freezer. By means of them it has become possible to state whether a bird entering the freezer in visually good condition is really so in the sense of maintaining quality for the maximum commercial keeping time. Since the object of the freezer is to preserve the flesh as nearly unchanged as possible, such methods must be resorted to for the recognition of differences which are minute when freezing is applied, more apparent when it ends, but striking before market- ing is accomplished and the bird eaten. On the basis of such work improvement in present methods must follow and new practices will be devised. A large part of the poultry now lost as foodstuff by decomposition will be saved when the reasons for its spoiling shall have been made plain to both packer and receiver. And last, but not least, such work, brought to the attention of the public, must tend to do away with such prejudices as those which cause the consumer to demand scalded rather than dry-picked chickens and often to sweepingly condemn all cold-stored supplies regard- less of quality or the impossibility of furnishing fresh produce when it is demanded out of season. a This has been adopted for commercial use by certain progressive packers." b. Unpublished studies of Food Research Laboratory, Bureau of Chemistry U. S. Dept. Agr. 3 º 633 Report of Proceedings of Commission III. 1* Sitting, 6* October, 1910. The sitting began at 2 p. m. and ended at 5'15 p. m. Honorary President: Dr. Edgar v. Cram m, councillor of state; President: Dr. Konstantin M a y er; Vice-Presidents: Leopold Engelh art and I. A. Sim a & e k; Secretary: Dr. H. Nübel. Vice-President L. Engelhart opened the sitting with the following address: t Gentlemen, As Ist Vice-President of this Commission of the II* International Congress of Refrigeration, I have the . honour, acting for the President, Herrn Magistratsrat Dr. Konstantin M a y er, who is hindered by an official journey for study, to welcome the members of the III" Commission. The announcements for the III* Commission were happily very numerous. There were a very large number of interesting papers notified, and I can state, with great pleasure, that in this Commission, whose discussions will be of the greatest importance not only for science but also for practical life and its economical requirements, very many of the greatest minds of all nations have assembled for united work. I welcome the official delegates from foreign states and Austria-Hungary and all other members of the III" Commission. Permit me to omit an individual welcome and introduction. I bid you all welcome and now invite you to enter upon the discussions. With the great quantity of matter that has to be dealt with in our sittings, you will excuse me if I put forward the request that time be economised as much as possible in the discussions. Greatly as we desire a thorough explanation of the interesting themes, we must yet impose upon ourselves a certain limitation. I have now the pleasurable duty of requesting you to choose an honorary president. I will mention a number of names of persons whom we shall invite to take part in the work of presiding. In this manner it is hoped as far as possible that all nations may be represented in the presi- dency and alternately take the chair. 634 The proposal includes the following persons: Prince Roland B on a part e (France); Mr. Deniss off and Dr. Edgar von Cram m, councillors of state (Russia); Mr. Knoke, secretary to the German Society of Refrigeration (Germany); 2. Mr. Le on a r d, secretary to the English Society of Refrigeration; Mr. Ru d dic k (Canada); Prof. Curt e l, Mr. Gre b a u v a 1, Mr. Jupp on tº (France); Mr. Schou, (Denmark); Inspector J. M. Bo t t e m a n n e (Holland); Dr. Ott a vi, Prof. Ru at a, Major della V a 11 e (Italy); Prof. Dr. M. Th. Wagner (Luxemburg); Mr. B a r c 1 a y, H. Bu 11 (Norway); Ing. Mattos B r a a m camp (Portugal); Prof. Knut Ljung m a n (Sweden); Dr. Fernando Perez, minist. extraordinary, Mr. Nicolas Su á re z (Argentine Rupublic); * Dr. Ludwig Ball a i, Mr. Heinrich Küs z1 er, Dr. Stefan Ko e r fer (Hungary). I take it that you accept our proposal and beg for eventual further proposals. (Agreement.) - *. I beg the gentlemen chosen as Honorary Presidents to take places at this table and alternately to undertake the work of presiding. I beg Mr. Dr. von Cr a m m, representative for Russia, to whom I give up the chair to act first. President Dr. v. Cramm, Imp. Councillor: I thank the assembly for the transfer of the chair. I first invite Mr. Dr. B titz le r, director of the abattoir at Cologne, to give his paper on 2 Ch a ng es in the physical and morphological condition of foods (meat, fish and milk) through cold.<. Direktor Bützler (Cologne) reads his paper. (See p. 363.) Dr. Emanuel Stehlík (Prague) proposed, speaking in French, that the Austrian Government be invited to introduce without delay modern reforms regarding the transport of frozen meat on railways, in order to make the import and consumption of this meat more easy. President: The question of meat import from exporting countries will be dealt with at the sitting in which the wishes of the Congress come up for discussion. Pusch (Budapest): The present method of preserving fish, especially fresh-water fish, consists in congealing the fish and then keeping it at a very low temperature (–8 to — 9 degrees). Dr. Bützler has said, however, that sea fish should be kept at a temperature of o degrees. We have had very good experiences with the former method with fresh water 635 fish. But Dr. B lit zler states that through freezing at low temperatures the fish is disintegrated and quickly perishes. Perhaps one of the gentlemen has had experience in this important matter. ~ .* Director Miles A Pasman (Argentina) states, speaking in English, that as director of a large cold storage company at Buenos-Aires, which has existed since 1887, he can, on the strength of his many year's experience, confirm everything that Dr. B titz le r has said about frozen meat. After 6 to 12 months the meat is in every respect equal to fresh meat, and loses nothing during preservation and transport either in quantity or quality. Marianne Stern (Vienna): Dr. Bütz le r said that the meat changed after 24 hours. I would merely like to remark that the meat, to be used in the kitchen, must thaw for at least 72 hours, before it is suitable and palatable for consumption. President: Dr. B titz le r said that the meat must be slowly thawed, but did not keep long afterwards. Dr. Susviella Guarch (Uruguay): I confirm the statements made by Dr. Bützler, on the strength of the experience we have collected during our many years' export of meat from Uruguay to England, Leo Hirsch (Consul General representative of Paraguay): As official representative of the Republic of Paraguay I beg to draw attention to the fact that Paraguay seems to be destined, by the side of Argentina and Uruguay, to enter the circle of meat exporting lands and refer to the brochures that are being distributed. President: I ask Dr. H. Martel, chief of the Paris veterinary Service, to give his paper on "The relative and a b so lute valu e o f frozen and chilled me at as fo o dº. Dr. H. Martel (Paris) reads his paper. (See p. 317) Dr. Fernando Perez, minister extraordinary, Argentina, states in French that England imports large quantities of chilled meat from Argentina and that the health of the English has in no way declined, but the economical conditions of the country have improved, the poor being able to obtain cheap meat. He suggests that the Commission should express the desire that states should open their borders to chilled meat, which should be everywhere placed on the same level as fresh meat. President: Dr. Martel, in his very lucid statements, has proved that chilled meat, even after being kept for months in Cold storages, is in no way inferior to fresh meat. It therefore becomes evident that this meat should be introduced everywhere and among all classes of people. -- -- I submit this question for discussion. Ing. v. Raffay (Vienna): This subject does not belong to the III" Com- mission but to the VI* Commission. ---, President: Every Commission has the right to express wishes. We may express our opinions and all will then be placed before the higher authority. - - 636 F. Ch. Govers (New South Wales) states, in English, that he was pleased to hear that Dr. M art el confirms the fact that from a scientific standpoint frozen meat is equal to fresh, as regards quality. Dr. Martel's judgment is all the more valuable seeing that his own country is not interested in the question commercially. He further mentions that New South Wales possesses no fewer than 45 million sheep and that it has been proved for a series of years that mutton that is frozen and transported from six to ten weeks reaches its destination, England, in good condition. The greater the market for frozen and chilled products, the better the results for producers and consumers. President: I propose the following resolution. Steps must be taken to secure the removal of the difficulties which have hitherto hindered the import of chilled meat. * Zerwes (Frankfort): I beg to oppose this resolution and the discussion at all of economical questions in this Commission. The work of this Com- mission is to consider the Scientific side of the refrigerating industry, but not to influence the governments of various states in any particular direction. With the dissimilarity of different countries in respect of their production, and with the varying interests, only a few of the countries here represented could agree to this general resolution. President: It is not our intention to forward petitions to the govern- ment. The best way is that we lay our views before the Society of Refri- geration, which can then take the further steps necessary. It would not be fair to deprive those present of the possibility of expressing their desires. Our resolution might be worded as follows: The III* Commission expresses the desire that chilled meat be given the same rights in transport and the transfer to various lands that are afforded to fresh killed meat. Dr. H. Martel (Paris) remarks, speaking in French, that frozen meat loses nothing in nutritive value, if proper measures are taken. There are still prejudices against the use of frozen meat in the kitchen, because it is not yet understood how to take practical advantage of this product which, for example, in England is so highly esteemed. Chilled meat that is subjected to the slightest possible temperatures (about 1") so that freezing does not take place, represents a food whose appearance and quality differ but slightly from those of fresh meat. It is stored meat, which is very digestible and keeps for a long time if the cold rooms are supplied with dry air and the meat is outwardly dried before the preservation. The cooling has also the advantage that it kills parasites. This is of great importance in the colonies, especially as regards cattle. In general governments ought to further the use of artificial cold, and it would be desirable that town and country work together to this end. He proposes the following wording for the resolution: Frozen and chilled meat form food products whose value equals that of fresh meat wherever artificial cold can be applied to healthy meat and with the desirable modern improvements. 637 Dr. F. Perez, Minister Extraordinary (Argentina) supports the resolution. President: The last two speakers desire that this question be dealt with from the scientific point of view. It was mentioned in Paris two years ago. The two gentlemen, however, are of the opinion that, on the basis of the inferences of Dr. Martel and Dr. Bützler, the Commission should express the opinion that meat can be kept in cold stores for a long time without suffering either in quality or quantity. -> Zerwes (Frankfort): The best gauge of the value of meat is its price. Frozen and chilled meat attain but a third or a quarter of the price of fresh meat. It is superfluous to say more. Besides this the hygienic side of the question must be considered. For the Import the meat inspection regulations of various countries come into consideration. It must, however, also be remembered that the meat, even if it can be preser- ved for a longer period, must also reach the cooking pot in healthy condition. Between the removal of the meat from the cold store and its preparation for the oven there lies a period of time which though not long is yet, dangerous. The equality of frozen and fresh meat must be denied in all circumstances. F. Ch. Govers (New South Wales) states speaking in English, that many people are prejudiced against frozen meat although it has been pro- ved that the difference in quality exists only in fancy. This is the cause of any difference in price. Director Dr. Bützler (Cologne): We have settled the matter from a scientific point of view, but I think that we cannot yet settle the practical side of the question, and that it is therefore not advisable to put the question to the vote. With the variety of the legal regulations in different Countries such a resolution would not assist us much. If for the present we keep to the scientific side of the question,-then service has been rendered to those countries also who do not admit frozen meat. Each country must decide for itself. Dr. St. Koerfer (Budapest): It is the desire of all that the people of every country may obtain meat at a cheap price. But we cannot make regulations for any government, I propose that the III* Commission merely acknowledge with thanks that it has been demonstrated from a scientific standpoint that meat preserved in cold stores, with proper treatment may be eaten without danger to health. President: We will close the debate for the present. Mr. A. T acco n is will be so good as to read the paper by Mr. F. Les car dé, engineer at Paris: • On the preservation of eggs by cold.<. F. Les car dé's paper is read. (See p. 406) President: I will now give my paper: "On Russia's turn over and export of perish a ble food products during the last ten year S.< President v. Cramm delivers his address. (See p. 547.) f 638 President: We now come back to the question of the value of fresh, frozen and chilled meat. The following form of the Resolution is proposed: > Frozen and chilled meat are food, whose value is at least equal to that of fresh meat, wherever cold is applied with the desirable modern impro- venents to fresh meat.< Bardach (Vienna): The words 2 at least& might give the impression that we considered frozen meat better than fresh meat. . President: We will omit x at least<. Bardach (Vienna): I think it is going too far to say that frozen meat is equal to fresh meat. President: That was decided at the Ist Congress. Ing. v. Raffay (Vienna): It may be said that at the present time there exists no objection to frozen meat, but that it is equal to fresh meat is scientifically false. - Director Dr. Bützler (Cologne): It is incorrect that frozen and chilled meat have exactly the same nutritive value as fresh meat. The practical side of this question is not ripe for discussion. Dr. Koerfer (Hungary): I do not accept the Resolution. For exact precision it would, moreover, be necessary to add: x of healthy animals.<. Marianne Stern (Vienna): Since the albumen content, which is the most important, is sometimes greater in imported meat than in fresh meat, the former may certainly be considered equal to the latter. Ing. v. Raffay (Vienna): The meat that is eaten is not identically the same as that frozen and chilled, because a series of dangers accompanies the thawing process, the causes of which are not yet known. The Congress should draw attention to this. Dr. Martel has quite correctly remarked that a layer must be destroyed by fire. It is not to be thought of to compare two different kinds of meat in a later state. A comparison would only be possible if the same quality, the same breed, etc. were examined under similar conditions in the one case in a fresh state and in the other in frozen state. This should be added to the Resolution. - President: It would lead too far so to detail this question. As a matter of fact the present day system of transporting fresh meat in open wagons has also various dangers. I believe the resolution accords with the views of the majority. Those who are of the contrary opinion can apply to the highest authority, the Refrigeration Society. We will now put the reso- . lution to the vote. (Done.) The Resolution is accepted by the majority. - Barclay (Norway) explains, in English, his method of transporting fish, and invites those attending the Congress to taste some. - - 639 2” Sitting, 7” October, 1910. The Sitting began at 10 a. m. and ended at 1:30 p. m. Honorary Presidents: Dr. v. Cram m, councillor of state (Russia); Heinrich Küszler, General Director (Hungary); Dr. Fernando Perez (Argentina); Vice-President: I. A. Šimaëek; Secretary: Dr. H. Nübel. President Dr. v. Cramm: I open the Sitting and give up the honour of acting as President in favour of Herr Generaldirektor Küszler. Küszler (Hungary): I think we should request our President Dr. v. Cram m, who led the discussions of our Commission not only yesterday but also in Paris, to continue to act as President. (Cheers.) President Dr. v. Cramm: I accept the presidency and give the follo- wing information: The representatives of Australia, Sir William Hall Jones, Sir Thomas Robinson and Sir John Taver n e r have proposed a Resolution to the following effect: "Proceeding from the opinion of this Congress that every practical measure by which healthy and perfect conditions are to be obtained must be furthered, all limitations should be removed or made less severe by which the import of frozen and chilled meat and other foods is hindered in those countries whose population could derive advantage from this increase in the quantity of foods. º rº- Zerwes (Frankfort): I request the Commission to express the most decided opposition to this. It is intended to raise fresh trade-political questions. The Congress must not be misused for this purpose. The decision regarding the admissibility of the import of foreign meat must be left to each individual state. The task of the Congress is merely to decide as to what is proved by science and practice. President: Governments send their representatives to international congresses to hear the opinions and feelings that are expressed. The experiences at the congresses form the basis for further discussions and steps by the Governments. I am myself representative of a Government and I consider it desirable that the Commission express itself, both majority and minority, the latter being free to enter a separate vote. Ing. v. Raffay (Vienna): I must again point out that it is not the task of the III* Commission to discuss trade-political questions. The Resolution would moreover have to contain the limitation that from a hygienic point of view — at last as far as previous experience goes — there was no objection to the import. Whether the import is actually justified or desired, however, must be judged not solely upon the hygienic interests of individual States but also upon other interests. President: The Resolution is almost identical with that which we accepted yesterday, and I consider it superfluous that we enter upon further controversy. We take it simply ad referendum, the views of the minority are shown by the reports of proceedings. 640 Taverner (Victoria, Australia) in the English language: It has been proved during many years' axperience that the chilled meat of Australia reaches its destination in fresh and absolutely good condition. The trade with Australian meat, like everything new, had at first to overcome many prejudices and had to reckon with the opposition of home dealers. The State Victoria, which I represent, and the other States of Australia take part to a great extent in providing England with fresh meat. England produces but 20°lo of her requirements. Our laws regarding sanitary officers are very strict. The Government takes care that nothing but healthy meat of good taste is exported. An examination takes places before and after slaughter. The question of meat transport over long distances is solved. The greatest attention should be directed to the execution of refrigeration transports and Governments should exercise the exactest supervision over purveyors and productions. 3. Sir William Hall Jones (New Zealand) speaking in English, declares: the Resolution merely implies that countries whose population is increasing should draw advantages from the import of meat from other countries whose production is greater than their needs. The speaker discusses the enormous export from New Zealand to England, exceeding in value the sum of 90 million Kronen, and that for frozen meat alone. He further states that the agricultural producers in England were originally very much against the import, but that time proved that the prices for inland meat yet remained high. Taverner (Victoria, Australia) states in English that the question of preserving meat is not only a question of export but is also an inner question because by it the possibility is gained of procuring cheap meat for the people. Chilled meat is a cheap food for the people. Himself he only eats fresh meat because he still entertains the prejudice and consequently must pay the higher price. (Cheers). Zerwes (Frankfort): I ask the President which point on the day's programme is actually being discussed, and the Commission whether it is desirous of effecting practical work. President: The discussion is relevant and bears upon yesterday's Resolution. -- Perez (Argentine Republic) in French: It is incorrect that the Com- mission may not discuss this question. The Congress has to examine all politico-economical questions that have connection with the Refrigerating Industry. What is the use of discussing refrigerating plants if chilled meat cannot be freely introduced in commerce We must examine the questions from a scientific, commercial and practical standpoint! We must settle whether refrigeration plants are capable of furnishing the people with good and cheap food. President: I also am of the opinion that we have to examine this question. I give everyone opportunity to express himself pro or contra. 641 There can be no suggestion of puff. It is evident that each delegate seeks to point out the advantages of his country. (Cheers.) Ing. v. Raffay (Vienna): The Resolution we are discussing belongs to the VIth Commission. We look forward with pleasure to the explication of the scientific side of the question. But the question whether meat can be imported into any country, even if there exists scientifically no hygienic objection to its preservation, belongs to another sphere. If Mr. President believes that it is a matter of a fight between agrarians and refrigeration industrialists then I remark that 1 am not so strongly agrarian that my clear conception should be dulled. As regards the influence of chilled meat upon the price of fresh meat it must be remembered that the price of fresh meat can only remain unchanged so long as imported meat is placed on the market in limited quantities. If a sufficient quantity is introduced, and if, as many of you maintain, it is better than fresh meat, then it is not possible to understand who shall buy the expensive fresh meat. Then the price of inland meat must from necessity be abandoned. Dr. St. Koerfer (Budapest): Please pass to our programme for the day. President: We are dealing with the questions on the programme of the day. I would like to give those members who were not here yesterday an opportunity of stating their views. Robinson (Queensland) speaking in English, states that it is very desirable that they discuss refrigeration but it is still better to apply it practically. In Australia we have collected many experiences relating to the refrigerating industry and refrigeration transport, and the methods em- ployed at present are very perfect. In Queensland, the state which I represent, not only is the greatest care paid to the keeping and feeding of cattle, but a careful control is exercised by the government over slaughtering, preserving and transport. Special certificates must be provided to certify that all the regulations of the government have been complied with, and my government would willingly enter into negotiations with the European governments to ensure the products entering Europe in healthy and suitable condition. The difficulties which stand so unfortunately in the way of the import of good and cheap meat should be modified or entirely done away with. Hütter (Vienna): Nothing can more interest the Commission than to hear how artificial cold can be employed for the utilisation and exchange of goods. If delegates from England explain to us the beneficial effects of the refrigerating industry on the import of foreign meat for the purpose of satisfying the requirements of European chief centres, then that is cer- tainly one of the most interesting points of the discussions of the Com- missions. I can only confirm that the import of cooled meat has had no great influence upon the prices of fresh meat on the London market. It would, however, be quite impossible to provide London with meat if one did not make use of foreign meat. If we can prove here that the Refri- geration Industry is able to preserve products destined for human con- 41 642 sumption and to transport them over long distances, then the Congress has done a great service to the world in general, especially as regards the pro- visioning of large towns. (Cheers.) President: We will now close this discussion and first here some lectures. + * In completion of my yesterday's paper I will now read a paper on *The present and future of the export of butter, meat, pigs etc. from Russia to Englands, in the English language. Present v. Cramm reads his paper. (See p. 545.) Robinson (Queensland) speaking in English states that the English market has lately been demanding large quantities of fish, especially salmon. He draws attention to the fact that in Siberia, in the Amur district, there is very good fish, which could find a sale on the English Market. Other countries, too, could find a good market for their products. President: Dr. Em. Stehlík, Magistratsrat at Prague, will give his paper on "The application of cold in the slaughter houses and market halls of Prague.< Dr. Em. Stehlík (Prague) reads his paper. (See p. 515) President: Dr. Nello Mori (Italy) will give the paper by himself and Dr. Alexander Costa on 2 Experim ents on the preservation of horse flesh by means of cold and its a pp lic at i on for purposes of food.» Dr. Nello Mori (Italy) reads his paper. (See p. 339.) President: I think that the III* Comission should express the opinion that according to all previous experiences chilled horse flesh can be used as food, provided that all safety regulations are complied with that are also demanded in the case of chilled flesh of other animals, provided, further, that a strict control exists and that the meat enters the market distinctly designated as horse flesh. Zerwes (Frankfort): It is not stated in the paper that preserved horse flesh has the quality possessed by other meat of keeping for an unlimited time. It would be necessary therefore to state in the resolution that the meat can only be preserved for a limited period of time. This depends upon bacterial properties in the meat. In the case of horse flesh a poisonous developement sets in within a very short space of time. The statements of the speaker to the effect that the military caterers on the battle-field should preserve the flesh of the fallen animals and make use of it for the troops must be dealt with with the greatest care. It would be best to enter no resolution on this point. Prof. Dr. Schwarz (Mährisch-Ostrau): I would consider it dangerous for us to form a resolution regarding horse flesh. We propagate in the first place the Refrigeration Industry, and should not trouble about particular kinds of meat. It is sufficient to confirm the fact that refrigeration may also be employed for horse flesh. The Agrarians might perhaps say: according 643 to the resolutions of the Congress you can eat horse flesh so the import of cattle is unnecessary. (Cheers.) Sluka (Vienna): We ought not to attach too much importance to this question. In modern times the horse is increasingly dispensed with, and horse flesh will perhaps become dearer than beef in the future. Generaldirektor H. Küszler (Budapest): As the question of the preservation of horse flesh is not yet sufficiently elucidated it is too early to-day to form a resolution. The question might be considered, nevertheless, for automobilisation is really not so rapid of progress as the foregoing speaker thinks. I suggest that the question of preserving horse flesh be placed upon the programme of the next congress. Prof. Dr. Wagner (Luxemburg): From what has already been said about horse flesh it is evident that horse flesh can be preserved by artificial cold, but that the artificially preserved horse flesh embodies certain dangers. It is, however, further necessary that horse flesh shall be sold as such if it is to be used as food for the people. I believe that we do not exceed the limits of the III* Commission by putting forward this demand. Prof. Dr. Postolka (Vienna): The question of the preservation of horse flesh is not yet solved by a long way. Practical trials in slaughter- houses and refrigeration stores have not given any absolutely satisfactory results although these refrigeration stores were fitted with the most modern arrangements. - In Vienna the refrigeration stores built for this purpose, although the parties interested explained their advantages, were finally not made use of at all. Nor is the question entirely solved from a scientific point of view. Nor is the glycogen question entirely explained. The glycogen test, by which it can be proved whether a piece of meat is horse flesh or not, fails in many cases in which glycogen is found in quantities as Small as in the flesh of other animals. Therefore, though the advanced time prevents my examining more deeply into the matter, I believe that the Congress should not yet take up the discussion of this matter. Direktor Dr. Bützler (Cologne): From a veterinary stand-point I would like to second the proposal that the question be placed upon the programme of the next congress. We have not sufficient experience at present. It is principally old horses and in great part sick horses that are slaughtered at present, but not the young and fat horses. Dr. Costa and Dr. M or i propose that the military authorities should arrange a special service for the purpose of preserving by cold, on the battle-field, the flesh of horses that have been killed or rendered unserviceable and making use thereof as a reserve of food for the troops. I must declare myself most emphatically against the preservation of sick horses. *. J. A. de Bernard (Russia) in French: The question under discussion is in general of great importance and is of special interest to Russia, where a great part of the population, namely almost 12 million Mussulmen, eat 41% 644 horse flesh as a rule and for preference. Russian Veterinaries maintain that horse flesh is less harmful than beef and that horses do not have many sicknesses that are common to oxen, e. g. Tuberculosis. From this point of view we should not speak of the quality and the commerce in horse flesh, but merely deal with the conditions of preservation. I join with the suggestion that this question be left over for study until the next Congress. * Dr. Albert Krüger (Berlin): I would like to ask if there is any harm in storing beef and horse flesh in one and the same refrigerating room * In a refrigerating house in Berlin the slaughterers raised objections to this. The question is whether these objections are justifiable. It might be that transfer of odour or something of that sort takes place. Hütter (Vienna): I must protest against horse flesh and beef being stored in the same room. Cases of mixing up have actually occurred. The trade is not always carried on by practised persons. There are more meat sellers than real butchers. It is easily possible to arrange separate depart- ments for horse flesh in store-houses. President: We will return again to this question, Dr. Fernando Perez, Minister Extraordinary for Argentina, in Vienna, will now give his paper on >The s an it a ry condition of cattle in Argent in a.º. …~" Minister Extraordinary Dr. F. Perez (Argentina) reads his paper. (See p. 565.) President: Miss Marianne Stern, head of a cooking and housekeeping school in Vienna, will give her paper on 2 The use of frozen a n d chille d meat in the kitchen.< Miss Marianne Stern (Vienne) reads her paper. President: We now come back to the resolution on horse flesh. Ing. v. Raffay (Vienna): It should be stated in the resolution that the time of preservation is limited. President: We will be still more careful and say that horse flesh must not enter the market without the permission and control of the authorities. Ing. v. Raffay (Vienna): I would like the question to be left for the next Congress. All remaining points could be left, as it is not possible to decide upon them to-day. * Hütter (Vienna): I beg to point out that what is spoken of in the first resolution: Horse flesh must not be sold without control, is already carried into effect in Vienna and other towns. Horse flesh is also chilled already. President: Already a great part of humanity live on horse flesh, in Russia millions of people. We are in favour of horse flesh being kept separate from other meat. In Russia there is much abuse in this respect. Generaldirektor H. Küszler (Budapest): I propose that we discuss the matter once more to-morrow, before the official sitting. 645 President: We will continue the discussion of the question of horse flesh to-morrow. - I close the sitting. 3* Sitting, 8* October, 1910. The Sitting began at 10 a. m. and ended at 1.30 p. m. Honorary Presidents: Dr. Edgar v. Cram m, councillor of state (Russia); Generaldirektor Heinrich Küszler (Hungary); Dr. Mary E. Penning ton (United States); Minister Extraordinary Dr. Fernando Perez (Argentina); Vice-President: I. A. Šimáček; Secretary: Dr. H. Nibel. President v. Cramm, councillor of state: I would like first to put the question who will take over the chair to-day Generaldirektor H. Küszler (Hungary): I beg to request our yesterday's president to continue to conduct the presidency. (Agreement.) President v. Cramm, councillor of state: In agreement with the Commissary General I propose that the representative of the United States, Miss Dr. Mary Penning to n, be elected honorary President. (Agreement.) His Excellency General v. W end rich will speak first on 2 The n our is h m ent of n a ti O n S.< v. Wendrich, councillor of state, reads his paper. (See p. 523.) Bauwens (Belgium): The question belongs to the VI* Commission, since statistical questions are in the first place matter for the administration. I propose that we proceed to the programme of the III* Commission and do not encroach upon the sphere of other Commissions. President: The paper has been sent down to the III" Commission by the Generalcommissariat. I believe that for the rest no objection will be raised to this paper, and proceed with the programme of the day. Prof. Alois Schwarz will give his paper on 2 Application and arrange m ent of Oz on e app a r at uses in refriger a ting room sk. Prof. Alois Schwarz (Mähr-Ostrau) reads his paper. (See p. 500.) Musmacher (Cologne): At one time we introduced ozone apparatuses in Cologne, not because we had a disagreeable smell in the cold store, but because the meat, which was stored for about three weeks, became slightly mouldy on some parts. On the introduction of the ozone apparatuses this mould vanished. At first we only used the ozone apparatuses for the spotty meat, but later on we used it in the other cold rooms as well, and we found that the disagreeable smell disappeared through the ozonizing. The saving is very great. Previously we had had to take care that warm air did not enter during airing of the cold store, and accordingly made use of the cool night air. But since we have ozonised we have had a saving of from 3 to 4"/, on coal, so that the apparatus is amortised and bears 646 interest. If eggs lie from spring until autumn the straw in which they are packed gets somewhat musty, and from autumn till spring there is a musty smell in the cold store. Here too, we ozonised the air, but only just enough to make the smell of ozone noticeable; to do more would be harmful. The air should merely be sterilised. The loss on eggs, which usually amounted to 3°/o fell to between 1+/, and 2%. Our trials were only made last year. The result is perhaps not to be entirely attributed to ozonising. I consider the purification of the cold room air by means of disinfectants to be a good addition, but not as absolutely necessary. (Cheers.) Zarotschenzeff (Russia), speaking in French, confirms the statements of Prof. Sch w a r z. In Russia there is a great interest for these ozone apparatuses, and in Moscow experiments have been conducted on a large scale. Hens with which such trials were made satisfied all requirements. The Agri- cultural Institute in Moscow has put up several apparatuses for experiment. Dr. Mary E. Pennington (United States) states in English that ozone apparatuses have been put up in America, too, specially for cold rooms in which poultry and game were kept. The success has been so great that the plants will shortly be enlarged. (Cheers.) President: I think the theme of Prof. Sch w a r z is settled. Prof. Sch w a r z is so well known a figure in the sphere of refrigeration technics and his statements are so exact and consistent that we have nothing further to do than to express our best thanks to him. (Agreement, Cheers.) h Dr. Mary Pen n in g to n will give her paper on 2 Refriger a tio n of p ou 1 try a n d e g g s in the U n i t e d St a t e S&. Dr. Mary E. Pennington reads her paper. (See p. 592.) President: The paper of Dr. Pe n n i ng to n is to a certain extent a continuation and completion of the very interesting paper which she read two years ago in Paris. I now request Dr. Pe n n in g to n on the basis of the election previously taken to take place at the Presidents’ table. (Cheers.) I think we should now pass to the resolutions that lie before us and continue the reading of the papers later on. Is my proposal accepted? (Agreement.) • First General v. We n d rich entered a proposal. It runs : * For the simplification of the measures that are necessary as aids to the feeding of the people and the provisioning of the army, during peace and in time of war, a statistical committee is to be formed in the management of the International Society of Refrigeration, and the forwärding returns of the means of transport must serve as basis for their works. Is this resolution accepted 2 (Agreement.) No objection is raised. w Further we have a resolution on the horse flesh question, about which we spoke yesterday. Herr Generaldirektor K is z1 e r has now come to an agreement with the gentlemen, and there will probably be no difficulty in the way of the passing of the resolution: It runs: "As there is no objection * 647 on principle to the use of chilled horse flesh so long as it is in a state of perfection and is expressly sold as Horse flesh , and as on the other hand further studies of the question of the application of chilled horse flesh for nourishment in general and for the provisioning of the army in certain circumstances, in war in particular, will bring the Solution of the question nearer, this important question is placed upon the programme of the next Congress.< Is this resolution accepted in this form 2 (Agreement.) Dr. Maximus Neu may er, a traveller for discovery in South America, will say a few words on the subject of horse flesh. Dr. Max Neumayer (Vienna). At Buenos Ayres, in 1904, I exhibited some trials of prepared horse flesh. These were in part pickled and in part sausage meat. The meat was very well received in Paris and Liverpool. It had a very good appearance, especially the pickled meat wich had a better appearance than beef, and the workmen preferred it to the beef. Horse meat is much more nourishing than beef. I also made a trial of an extract and obtained 8 kg of extract from 1C0 kg of meat. In Argentina horses are very cheap, and the country is still very rich in horses. Among other uses the meat goes to Belgium. President: There is a proposal before us by Mr. Ert 1 of Vienna, which runs: "The obtention and application of natural ice for the preser- vation of foods and food products should be most carefully watched by the sanitary authorities and eventually entirely prohibited in cases of epidemics. Natural ice may only be used for preserving food and food products if it is certified as being free from objection hygienically by a State testing institute.< Ertl (Vienna): I would merely like to mention that I agree with the lately published results of examinations of meat by the Royal Testing Institute in Bavaria. It has been proved that disease germs occur very often in natural ice. Particularly in the case of cholera measures should be taken that only such ice should be made use of in preserving food products as has been certified by a state testing institute to be suitable. - Gerlei (Hungary): For the preservation of food stuffs only ice from pure water should be employed. The proposal, however, will probably not Satisfy this purpose. I suggest that the resolution be stated as follows: Natural ice that is used for preserving food products may only be made from water that is passed by the authorities as suitable for drinking. Prof. Dr. Wagner (Luxemburg): A similar resolution was drawn up in the Congress of 1908. Ing. v. Raffay (Vienna): Natural ice can only be harmful if it comes into actual contact with the food products. The proposal before us is so intended. It must be remembered that artificial ice or ice that is hygieni- cally free from objection is not always obtainable. President: All that is proposed here has already been decided in Paris. 648 Zerwes (Frankfort): The proposal before us goes too far. The use of natural ice is dangerous only when it comes into contact with the food. The resolution must therefore read: 2 For direct coolings. * Bull (Norway): Very much natural ice is produced in Norway, which is also sent to England. I agree that natural ice should be examined by the authorities. But if it is examined it need not be absolutely prohibited. This passage should therefore be omitted. President: Russia is also interested in this question, on account of her great production of natural ice. At the Congress against the adul- teration of food products held in Paris the resolution was worded to the effect that natural ice should under no circumstances be used for direct cooling of food products, if the ice was used in direct contact, thus for instance natural ice may be used for cooling drinks if it is not put into them. In spite of this however an exception was made. In districts in which natural ice predominates and artificial ice is not to be obtained without difficulty, the use of natural ice is permitted if a certificate of a chemical laboratory is provided. I make the following proposal: For a compromise the III* Commission confirms the resolutions, concerning the trade in, and use of natural ice, which were passed by the Congress against the adul- teration of food products which was held at Paris in the year 1909. Bull (Norway): I am for the resolution. Gerlei (Hungary): The resolution of Paris does not cover what we want to-day. With us there is present danger of cholera. The Danube is infected. Much ice is taken from the Danube. If an ice safe is cooled with such ice there is danger that the microbes from the thaw-water get into contact with the meat. If infected ice gets into the market there arises the great danger that food stuffs will be preserved with it. Therefore I consider that my proposal will be entirely satisfactory. President: I think it is right that we should always express our approval of previous Congress resolutions. Mr. Ger 1 e i is right as regards epidemics. I would therefore like to add: During an epidemic infected water may not be used. Ertl (Vienna): That is stated in my proposal. Director Dr. Bützler (Cologne): I merely point out that in my paper read on the first day of the sittings I mentioned that fish are cooled directly in ice, President: A great part of the world can only use natural ice. I think we are agreed that wherever water is under hygienic control the use of infected water must be prohibited in cases of epidemics. • § Bull (Norway): It is not necessary to make a clause that shall prohibit the use of infected water in cases of epidemics, seeing that the resolution already says that the natural ice must come from wholesome water. Dr. St. Koerfer (Hungary): We should say: Natural ice that is used for cooling food products may only be produced from such water as is permitted as drink water by the authorities. 649 - President: That is somewhat too general. With us in Russia the Newa is infected with cholera bacteria and yet we obtain drink water from the Newa, by using various apparatuses that destroy the bacteria. But if the water is directly used as ice it is infected. I propose that in the case of epidemics special attention is to be paid to the production of ice to see that it is made from faultless water. V. Herczeg (Hungary): We must take such steps that even the arising of epidemics is prevented. There are many countries where the intro- duction of waste water into the rivers is not prohibited, where, therefore, the danger of infection is ever present. I would therefore like the Paris resolution to be completed by adding the prohibition of the use of natural ice at places where food stuffs are sold. President: I propose the following wording : *The Commission agrees with the resolutions formed at the International Congresses on Refrigeration matters and against food adulteration, and adds that natural ice that is used for the cooling of food products may only be made from water that is hygienically free from objections. I think that in this form we could close the resolution. We come to a proposal by Dr. Olivier Jacobi which runs as follows: The III* Commission expresses the desire that a chilling and freezing store house which produces artificial ice in large quantities must be scheduled as a factory. Dr. O. Jacobi (Hungary): My proposal appears really to be a self- evident matter. The question, however, has become controversial in a revenue case. The view against which my proposal aims holds that the refrigeration works do not manufacture an article of industry and can therefore not be counted as a factory. True enough the cold manufactured at refrigerating works is not packed up and forwarded, but only used at the point of production. But the possibility of transporting the products does not in any way belong tho the work of manufacturing. President: As the question is of revenue importance I could easily produce a great amount of opposition to this resolution. I propose that the resolution be laid before the International Society of Refrigeration for further examination. (Agreement.) Dr. O. Jacobi (Hungary) declares himself in agreement therewith. (The resolution was thrown out by the meeting of delegates.) President: We have one more resolution: The Delegates from Argentina request the III* Commission that the International Society of Refrigeration be requested to take the initiative in calling together an international conference in 1911 in Paris, which shall consist of the representatives of the states that import and export meat, and whose task it shall be to draw up an international, uniform method of examining the chilled meat, & w Zerwes (Frankfort): I would like to point out that a similar resolution was passed at the I* Congress of Refrigeration, according to which it was 650 considered desirable that a uniform method of meat examination be establiahed, the council of London being entrusted with the study of this important question. We Ought therefore to apply to the council of London with the enquiry as to whether it can fulfill this request. President: It is true that at the I* Congress such a proposal was made, but then the International Society of Refrigeration was founded to which all matters were handed over for further discussion. The Society of Refrigeration has taken no steps worth mentioning in this matter so far, and is awaiting further statements from the II* Congress. The representatives of Argentina declare that it is necessary to take steps in this respect because the gates of various countries are being more and more opened to foreign products. I think that we should lay the matter before the International Society of Refrigeration. - - - Ing. v. Raffay (Vienna): I think the II* Congress takes over the resolution of the I* Congress and asks the Council of London if it has already taken steps in the matter or if it would do so in the near future. President: As the International Society of Refrigeration has taken Over the matter that was originally placed before the London Council, but So far no settlement has resulted, I think it advisable to open up this important question afresh. * Boro di ne (Russia), Dr. F. Perez, Minister Extraordinary (Argentina), Hall Jones (New-Zealand), and Dr. Stefan Koe r fer (Budapest) support the proposal. *. Borodine (Russia) makes the additional proposal that all resolutions of the I* Congress on the meat question should be confirmed by the II* Congress. President: I have already said that I think it right to respect the resolutions of the I* Congress. I think that no objection will be raised to the proposals of the Argentine Delegates or Herr Boro dine. (Agreement.) We have also the following proposal: *The III* Commission submits the following resolution to the II* Congress of Refrigerations for ratification: In consideration of the great progress which has been made since the I* Congress in Paris in 1908, the II* Congress expresses the opinion that chilled meat, butter, eggs, cheese and other food stuffs that have been brought into refrigerating houses in healthy condition and preserved and transported with the application of modern refrigeration technics are not to be considered inferior to the fresh products, and that from the stand- point of science and technics there is no hindrance to their transport over long distances and their sale in all countries. • I point out that I make a difference between frozen and chilled meat. I speak of chilled meat. Barclay (Norway): I beg that fish may be also expressly mentioned in the resolution. * Dr. St. Koerfer (Hungary): I believe that chilled butter and cheese cannot be considered as equal in value with the fresh product. 651 Gerlei (Hungary): I agree with the previous speaker that butter should be absolutely excluded. This question is not on the programme of the Congress and should not be treated of until the next Congress, as we cannot ... at once form a resolution on such an important matter, which would put all trade on new lines. - Hamelryck (Belgium) speaking in French states that the question of the relative value of frozen, chilled and fresh meat, as is evident from the debate, is of great interest on account of its great importance, and the resolutions of the Congress will be awaited with impatience. There is, however, too little experience at disposal for them to come to formal resolutions which shall be scientifically maintainable. He therefore proposes the following resolution: *The Congress decides that the question of the relative value of frozen, chilled and fresh meat shall be studied in every respect and without delay in all countries, especially as regards the army, which is directly interested. The International Society of Refri- geration is requested to make known to all governments the programme of the most desirable information, the conditions being exactly determined which are absolutely necessary in order that the results may admit of scientific comparison. For the next Congress one delegate from each country should collect the information and local regulations. The results should be united in a report by the International Society of Refrigeration and laid in advance before the next Congress.< President: Permit me to add a few words on this matter. We saw at the Ist Congress that goods could be stored in the refrigeration rooms for years without change. Dr. Mary Pennington then showed us pictures of fowls which had already been kept in the cold store for 3'ſs years and which had shown no change either in biological or other respect. The application of cold in the transport of food products has proved to us that a great part of the loss that hitherto was unavoidable may be avoided by making use of cold. Cold has proved itself an excellent means of preservation. Last year we saw at the Congress against the adulteration of food products that in many countries strong poisons were permitted for conserving purposes. This method of conserving satisfied even the dealers and producers to but a small extent. Technics of refrigeration have not reached their highest point of perfection yet by a long way, but we must to-day, already, admit with satisfaction that they enable us to transport such products over long distances. I merely point to the fact that to-day Russian Butter from Siberia, Russian eggs and in particular Kaviar, which has to be so carefully dealt with, can be transported to nearly every country of the world in an absolutely unchanged condition. That has already been confirmed by the I* Congress, and I believe we could also agree to the proposal before us at this Con- gress. It is admitted as necessary that the products enter the refrigeration house in healthy condition, that the most modern plant is used and sanitary control exercised. In this manner cheap food could be procured everywhere. 652 We heard, yesterday, that in conservative England the Agrarians were very anxious because they feared injury to their interests, and that the prices in England to-day of fresh meat have in spite of this risen and are always higher than the prices of imported meat. We know that a product becomes cheaper the greater its turnover, but that the profit thereby is even greater than with the smaller turnover. I think that there will be no earnest objection to the resolution. We merely confirm here what the technicists have proved to us and the I* Congress has already confirmed. - Ing. v. Raffay (Vienna): Experience shows that butter goes through decomposition processes during the period of preservation, through which it is diminished in value. President: Have you proof of that? Ing. v. Raffay: My tongue. The fact is well known. President: The I* Congress laid down that butter suffered no change worthy of mention. Ing. v. Raffay: Preserved butter in no way injures health, but it loses its quality. The proposal of Major H a m e1 ry c k would satisfy the wishes of everyone who had connection with refrigeration technics. It would be very desirable that tests be made in this respect. - Dr. St. Koerfer (Hungary): I think an error has been made. Major H a me 1 r y c k speaks only of fineat, whilst in the first proposal other food products are also included. The proposal of Major H a melry c k must therefore be completed. Then we can approve it without more trouble. Zerwes (Germany). It is extremely displeasing that in this Commission for three days it has been endeavoured to bring trade political questions to the front, and that the representatives of meat exporting countries have so often been given occasion to speak. The question as to whether frozen and chilled meat are equal to fresh meat in value cannot be answered in the affirmative. The difference in value in London is no chance difference but a natural one, for when the frozen meat is thawed it does not look like meat any longer but looks like a wet, dirty rag. The changes which the preserved meat suffers between the time it is taken from the refrigera- ting chamber and the time when it is eaten may form a great danger for those who eat it. New experiments have proved that bacteria are present not only on the outside of the meat but also inside the meat. The surface preservation does not suffice therefore, but we must reckon with the possibility of bacterial growth within the meat. In America it is proposed to place a time limit to the period of cold storage. We have no doubt that the meat may be kept for a long time, even for 1/2 years, but from a hygienic point of view we entertain the greatest misgivings, As long as a uniform method of examining the meat does not exist there can be no talk of equality of fresh and imported meat. I would therefore like to ask that no resolution be passed, or that the proposal be stated as follows, that 653 exact examinations shall be made and that the question shall be left for the next Congress. If the vote is taken on the proposal of the President, I would recommend that only Congress members vote, and they for each country separately. T}r. F. Perez, Minister Extraordinary (Argentina), speaking in French points out that Argentina does not put forward any endeavours to increase her sale of meat in other countries than England, for instance in Austria or Germany. England is so ready to buy that the products of Argentina can always find a sale there. President: The statements of Mr. Ze rw e s are very instructive and interesting! They do not, however, agree with the statistics before us. We have here the complete material, the conclusions of the I* Commission and to a certain extent axioms before us. The resolution before us is only a continuation and completion. Mr. Zer we s is probably unacquainted with the amount of material that was before the I* Congress. Chilled meat is, from a hygienic point of view, absolutely suitable for food and lasting. Mr. Zer we s reproves us for dealing with questions that do not belong to our Commission. We have kept entirely within the frame of our daily programme. As regards the question as to whether fresh meat is to be valued higher than chilled meat we have nothing to do here. We only confirm that from a hygienic stand-point chilled meat is not inferior to fresh meat. Naturally it is cheaper. We desire to furnish the poorer among us with cheap food. That is the object of the Congress. We are representatives of the governments and also representatives of the people. (Cheers.) Hütter (Vienna); Mr. Ze rves, as representative of the German butchers’ society, has perhaps not looked upon the question from the point of view of political economy as the Commission has done. Every represen- tative of the meat trade must naturally be in favour of nothing but fresh meat reaching the consumer. That is the first principle of the trade. We are interested by the slaughtering of living animals, because we thereby obtain the valuable by-products. We wish, therefore to protect ourselves against the import of meat. But if there is a scarcity of meat, meat must be imported. If dearth of cattle prevails in the inland there is no other means of help for the masses than the opening of the borders to meat. On the London market I have repeatedly gained the conviction that it would be impossible to furnish the town with meat in this manner, if foreign meat were not imported with the assistance of refrigeration technics. The late examination of Argentine meat at Triest gave very good results. I can say that the meat was quite equal to our excellent Waldviertels oxen in quality. As for the lasting quality of chilled meat I affirm that I kept meat in cold storage and froze it for six months and was then able to make use of it in my business without it being noticed that the meat had lain for six months in cold storage. As representative of the Butchers' - Union of Lower Austria I must of course once more explain that our ideal 654 is not the import of slaughtered meat, but that it would be better for us' as industrialists if we had sufficient oxen. *. President: I think the question has been enough discussed. As various objections have been raised as regards butter, eggs, and cheese I propose the following form of reselution: * In consideration of the great progress that has been made since the Ist Congress in Paris, the II* Congress expresses the opinion that chilled meat, fish and other food products which were placed in refrigerating chambers in healthy condition, etc.<. Gerlei (Hungary): Please state expressis verbis: 2 with the exception of butter and cheeses. President: That would be confusing. In a separate resolution it could be stipulated that as regards butter, eggs and cheese further experiments were to be undertaken. Ing. v. Raffay (Vienna): The resolution cannot be accepted because in it preserved milk is represented as of equal value with fresh. Dr. M. Koerfer (Budapest): As milk farming expert I must express a warning against this resolution. - President: We will simply take the vote. (Done.) The resolution is thrown out. Regarding the proposal of Major Hamelryck we should in my opinion take the vote at our next sitting. (Agreement). I close the sitting. 4* Sitting, Io" October 1910. The Sitting began at 10 a. m. and ended at 1 p. m. - Honorary presidents: Dr. Edgar v. Cram m, councillor of state (Russia); Dr. St. Koerfer (Hungary); Generaldirektor H. Küszler (Hungary); Dr. Mary E. Penning to n (United States); Dr. Fernando Perez, Minister Extraordinary (Argentina). Vice-President: I. A. Šimáček. Secretary: Dr. H. Nübel. - President Dr. v. Cramm . The sitting is open. As to-day is the last day of Our discussions and we have dealt sufficiently with the great questions under our consideration I think that to-day we can settle the resolutions before us without debate. (Agreement.) We have the following resolution: *The III" Commission is requested to accept the following proposal which is made by the representatives of the States: Argentina, Australia, England, Russia, Norway, the United States of North America: The IIIrd Commission of the II* International Congress of Refrigeration expresses the wish that food products, which are treated with the aid of modern refrigeration technics, and which satisfy the legal requirements in respect of hygiene, nutriment and freshness shall find an unhindered market in international commerce K. s 655 A similar proposal was accepted by the I* Congress. I beg those ladies and gentlemen who are in favour of this resolution to rise in their places. (Done.) I declare the resolution accepted. I welcome Mr. Coghlan, General representative in London for New South Wales. Mr. Cogh 1 a n is of international importance as a specialist in the technics of refrigeration and will be pleased to furnish the hon. members of the Congress with information concerning the magnificent progress that Refrigeration has made. I believe it would be of interest to you if you accepted Mr. Coghlan's invitation. Further there is a proposal of the Russian delegate Councillor Borodine, which reads as follows: The III* Commission shall assert the desirability of all slaughter houses and all central market halls being compelled to be fitted with refrigerating plants. Will those members rise who agree to this proposal? (Done.) The proposal is accepted. *: Councillor B or od in e has also the additional proposal to the proposal of the Argentina delegates, regarding the uniform examination of meat: that the resolutions of the I* Congress in the meat question shall be confirmed. I beg those members who agree to rise. (Done.) The resolution is carried unanimously. We now come to the proposal of Major H a me I ry c k, the debate on which was broken off yesterday. The proposal is really self-evident. The Congress is summoned for the purpose of discussing all relevant questions in detail. The II* Congress completes the Ist Congress, the III" the II*, etc. We can certainly accept the proposal, but I do not know if it appears advisable, seeing that the matter is self-evident. I beg those members who are in favour of this resolution being accepted to rise. (Done). The reso- lution is negatived. I will now read afresh the resolutions that have been passed in earlier sittings, as during - yesterday, Sunday, the office has procured the exact reproduction in the three languages. Please put forward any objection. The resolution on horse flesh runs (reads): w > As there is no possibility of objection on principle to the use of chilled horse flesh, provided it is in perfect condition and expressly marked as horse flesh, and as on the other hand further study of the question of the use of chilled horse flesh may bring a solution nearer, be it for the general nourishment, or be it for the nourishment of troops in war under certain circumstances, the Congress places this important question upon the programme of the III* Congress.< The resolution of Sir William Hall Jones regarding the abolition of the limitations to the import runs (reads): * Proceeding from the opinion of this Congress that every practical measure by which healthy and complete conditions are produced is to be 656 assisted, all limitations should be removed or modified by which the import of frozen and chilled meat and other food products is hindered in those countries whose inhabitants could derive advantage from this increase of food products.< The proposal of His Excellency V. Wen drich concerning transport statistics runs (reads): »To make those measures easier which are necessary in the interests of the feeding of the people and the provisioning of the army in time of peace and in war it is proposed to form a statistical committee within the management of the Association Internationale du Froid, which hereby must take the conditions of transport into consideration.< & The resolution on the ice question runs (reads): »With regard to the use of natural ice the Commission agrees with the resolutions formed by the International Congresses on Refrigeration and against the Adulteration of food products in Paris, and adds that natural ice which is used for the preservation of food products may only be obtained from water that is free from objection. < Ing. v. Raffay (Vienna): For correction I would mention that the resolution was proposed in another sense, namely that natural ice may only then not be used if effective precautions are not taken. President: Everything is said in the words ºffee of objection. < Ing. v. Raffay (Vienna): The natural ice won under ordinary conditions cannot satisfy this condition. President: Every chemist and every medicinist will confirm that with the words Free form objection & everything is said and no addition is necessary. Ing. v. Raffay (Vienna): There is a misunderstanding. If it were stated *Use of natural ice for direct contact cooling<, then I would agree. In direct cooling with natural ice, we have expressly said: effective measures must be taken to avoid infection. President: It stands ºffee from objection «; with that everything is said. I may take ice from water that is free from objection, that contains no bacteria, and put it into my glass and cool my mineral water therewith. The Argentine Delegation has proposed the following resolution regar- ding the examination of meat (reads): The Association Internationale du Froid shall take the initiative to secure that an international conference of all states that import or export meat shall meet in Paris 1911; this Conference should have the task of forming a uniform, international method of examining chilled meat. I think that we will lay the resolutions before the Congress in this shape. (Agreement.) I ask the meeting whether there are other proposals which have already been passed or which I should read here. (Pause.) 657 This not being the case Herr L. van Wanjen be rgh (Brussels) will give his paper: "The use of artificial cold for the preservation of me at in s m a 11 quantities a n d in pick led State.< ** L. van Wanjenbergh (Brussels) reads his paper. (See p. 401) President: Herr Dohm an n, slaughter-house director (Cottbus), will give his paper on "Suit a ble refrige ration plants in modern slaughter-houses.< Direktor Dohmann (Cottbus) reads his paper. (See p. 490.) President: I thank Messrs. van Wanje n be rgh and Do him a n n for their excellent papers and I believe that the meeting is entirely in agreement with the conclusions drawn by the two speakers. (Agreement.) We now come to the discussions on milk and dairy products, and I will take the liberty to hand over the presidency to Mr. Generaldirektor Küszler (Hungary). I would like still to express my thanks for the honour that has been done me in electing me as president. I have endeavoured earnestly to act justly to all parties, and I beg you to excuse me if I have not given to everyone what he desired and expected. (Applause.) Generaldirektor Küszler (Hungary): In taking over the presidency transferred to me I think that I state your views if I express the heartiest thanks to the retiring President Dr. v. Cramm, for conducting the presidency till now. (Agreement.) As questions of dairy management have now to be discussed I propose that Dr. Stefan Koerfer, director of the milk section in the Royal Hungarian Ministry for Agriculture, be asked to take the chair. (Agreement.) President Dr. Koerfer : On account of the advanced time we must now be sparing of words. Following the programme I ask Mr. Heiss, slaughter-house director, (Straubing) to give his paper: 3 Cold storages as accumulators for the provisioning of the army in the field.< Direktor Heiss (Straubing) reads his paper. (See p. 347.) President: I ask the members if they agree to the proposals of Direktor Heiss. The proposals are accepted. We now come to the paper of Dr. Charles E Marshall of the Michigan Agricultural Academy, East Lansing, on The effect of cold on the bacteriological and chemical changes of milk and butter on the basis of laboratorial studies in the United States. • Dr. Mary Pennington will be so kind as to read the introductory sentences of Dr. Marshall’s paper. Dr. Mary Pennington reads. (See p. 386) President: I think that the meeting is in agreement with the proposals of Dr. Marshall. (Agreement.) 42 658 Dr. Hans Messner, slaughter-house director, Carlsbad, will give his paper on >The importance of cooling animal food products, with Special attention to milk.< Dr. Hans Messner reads his paper. (See p. 421.) Charousek, dairy inspector, Vienna: In Germany and in Austria, just as in other civilised states the use of cold in the dairy trade is looked upon as a 2 conditio sine qua nons. It is true that with us in Austria every available means are made use of, even cold water from snow and natural ice. It is forbidden with us to bring these cooling means into Čontact with the milk. AS regards the preservation of butter and cheese by means of cold I would like to make a limitation. The use of butter is not to be thought of without the ripeness of the product. This is a chemical-biological process, no lasting condition. This process is stopped by the cold temporarily. The ripening progresses and when it has reached a point of culmination it passes over into Solution, that is, the alimentary food becomes an alimentary cadavre. The butter becomes worse, loses its colour, taste and aroma. I further draw attention to the following: There is an international dairy association which is older than the International Society of Refrigeration and which deals with all dairy questions. The matter has not yet been so deeply studied that we can form resolutions at this Congress. (Cheers.) Direktor Ludwig Gerlei (Hungary): The proposals of Dr. Messner contain only well known facts. We could only discuss the last question. It is impossible, however, that milk be transported in express trains. President: The paper of Dr. Messner was very interesting in many respects, although it is possible that in it facts were affirmed which may perhaps be considered as self-evident. I think we should hand over the resolutions to the president of the Congress, that this question may be continued on the programme. With regard to the statements of Dirktor Gerlei I beg to remark that Dr. Messner has perhaps goods trains in mind. v. Raffay (Vienna): Transport of milk by means of fast trains is im- possible for railway technical reasons. The speaker seems to have had goods trains in mind. Direktor Dr. Messner (Carlsbad): I meant slow trains; if I require anything I always demand more because I know full well that governements always knock off something. Mr. Barclay (Norway): I wish only to draw attention to the fact that in Norway fish can be regularly sent by fast trains. Obering. Verbir (Hungary): The proposer of the resolution desires that the products shall be forwarded to their destination with the greatest possible speed. Ing. v. Raffay (Vienna): We must not form wishes whose fulfilment is impossible. Perhaps it is to be recommended to say at the close of the resolution: * With the greatest possible speed, but in any case more rapidly than hitherto &. 659 Director Dr. Messner (Carlsbad): I agree. President: I beg those members who agree to Dr. Messner’s proposal, with this alteration of the final sentence, to signify their approval by rising. (Done.) Accepted. The proposals will be laid before the Congress. Engineer Lecomte (Spain) will give his paper on 2 A new appli- cation of cold for the production of concentrated or solid food extracts and especially for the manufacture of milk powderk. Lecomte (Spain) reads his paper. (See p. 419.) v. Cramm, councillor of state (Russia): We have here to do with the keeping or better said the re-making of a cheap albumen powder material. If we desire to procure cheap food products for the people we must in the first place consider the albumen contents. Meat is taken for food in large towns principally on account of the fact that but a compara- tively small quantity of it is necessary in order to add the necessary albumen to the body. It is well known that milk contains albumen sub- stances which are more easily assimilated than those of meat. It is, however, impossible for us to obtain the neccessary albumen entirely from milk, because milk contains about 90°lo water. The proposition of M. Lecomte aims at withdrawing from the milk, by simple means, the greater part of water content. The question cannot of course be decided with a turn of the hand, but must be examined from all sides. Without doubt the matter is of great interest, and I recommend the following resolution: "The III" Commission of the II* Congress of Refrigeration expresses the desire that the paper of the Spanish Delegate Lecomte be specially handed over to the International Society for the Refrigeration Industry for exhaustive Study, in order, perhaps, to produce a suitable and cheap albumen food that can be easily assimilated.<. Oberinspektor Verbif (Hungary): What connection has that with cold? Councillor v. Cramm (Russia): It is made with the aid of cold. It is a new process and is to be patented. Ertl, dairy technicist (Vienna): The process was lately described in technical papers. The water must not quite freeze at the moment the milk freezes but it must be of a thick consistency. The water is extracted by means of centrifugal force when at the freezing point. President: I think we can accept the resolution of Dr. Cr a m m without danger. Will those members who agree kindly rise? (Done.) The resolution is accepted. - Director Franz J. Kaiser will give his paper on >The use of cold in municipal dairy m an age ment.< Director Kaiser (Vienna) reads his paper. (See p. 412.) Prof. Josef Rezek (Vienna): I would only like to refer to one remark of Director Kaiser’s, that the quality of the various ice machine systems should be decided by the commission for examination of machines. I am manager of a state agricultural examination station and the fulfilment of a wish so much 42% 660 according to the public interests would be a natural duty if we were in a position to fulfil it without hindrance. In order that this may become possible I would like to give some helpful impulse. The examination of a small plant such as husbandry makes use of, if it is to be effected properly, involves such expense that it becomes really impossible. In this case I would suggest the following way out of the difficulty. In the execution of large plants one must individualise. In small work that is not necessary; then it would be natural that certain small normal types be produced, in which not merely the compressor but the whole ice machine plant, perhaps even the little house in which the refrigeration machine comes, should be normalised. Then it will no longer be necessary to examine the individual Specimen but only the particular type. I would like, therefore to give the impulse to the most far reaching normalisation of such small plants on the part of machine factories. Then we should be in a position to instruct the husbandman and the dairyman in a manner suitable to their practical needs. (Cheers.) -- v. Altrock (Berlin): It is of great interest to agricultural circles that arrangements be secured which make it possible that even the small, simple farmer may be able to draw advantage from the arrangements for cooling. I would merely like to draw attention to the fact that Messrs. Borsig of Berlin are examining very thoroughly into the question and are about to to sell so-called cool-ovens. I think that in this manner the small farmer can obtain arrangements that are simple and that cause but Small expense. I should only like to remark further that the proposal of the speaker is very welcome to Germany. It is exceedingly important that the representatives of industry all work to the same end with us agricultural representatives If we find such support from industry we shall succeed in obtaining better means of transport for milk and other perishable food products. That suggestion is very valuable which was made here in the form of a remark thrown in, and which asks if it is not to be recommen- ded that the introduction of refrigeration cars be made independent of the willingness of interested parties to make use of them. I think a bye-law could be made ordering that if the arrangement is technically perfect and the costs are not too high, milk and other perishable food products may only be transported in refrigeration cars. I would not like to omit to thank the reader of the paper for the particularly valuable suggestions that he has given to us. (Cheers.) President: Permit me, as expert, a few explanatory remarks. This spring, during the great dearth of ice, we instituted trials in Hungary in which we transported the whole of the milk that is sent to Budapest in refrigeration cars. The trials cost the government a great deal. We made enquiries among the large milk dealers in Budapest as to the effect. One stated that every year about 30°lo gets to him sour in Summer, but that this year it was only 17%. How far this is true I cannot judge. Naturally \ 661 I do not think of a completely sour milk, but of a milk that might be complained of. One can accept milk even if it has a slight sour taste, when one needs it; if one does not need the milk, and if it has a slightly sour taste, then one calls it sour. (Laughter.) - Marianne Stern (Vienna); I would merely like to say that it would be very agreeable if there existed small machines for house-keeping which made it possible to keep milk cool. + Oberstabsarzt Dr. Sickinger (Vienna); I would like to make the follo- wing suggestion: the public should be made aware of the fact that the boiling of milk is not of advantage. Here the dairies themselves might do something. Further it is desirable that something be invented to cool milk well and which housewives with modest means could purchase. (Cheers.) Kürner (Troppau): I agree with the statements of Miss Stern. I ma- nage three large establishments at Troppau. We have a cooling plant with sulphur dioxide, which system, however, we shall give up. I have been sent here by the Silesian Council to find out a new system. After the results of the discussions, however, I am at a loss what to propose. Prof. Dr. Wagner (Luxemburg). In order to introduce the knowledge of the rational use of cold in the management of land and gardens and in the connected industries, the teachers of agriculture should help by their teaching and lectures. - President: Mr. Birch of Copenhagen has requested me to inform you, as he is not sufficiently master of the German language, that in Denmark butter is only made from pasteurised cream and that skimmed milk may only be put on the market in a pasteurised state. He makes this remark because it is contrary to the remarks of the reader of the paper. More than this, cream is, in Denmark, brought into direct contact with the crystal ice, and it is believed that thereby a more lasting product is obtained. Ing. v. Raffay (Vienna): Small refrigerating machines come com- paratively expensive; in a refrigerating machine that has to give 500 litres daily, one litre costs 8 Hellers; in a refrigerating machine that has to control 1500 day-litres, only 8 Hellers. Studies respecting the cooling in city house-holds are very desirable. Direktor Dr. Gerlei (Budapest): In the interests of the Hungarian dairymen I would like to make a correction. Mr. President did not intend to say that in general 30 °/o of the milk that went to Budapest was sour. Budapest requires about 29 million litres of milk; of this 90,000 litres arrived sour, and that because there was no ice. We use for the most part Sul- phuric acid compressors and are very satisfied. For milk that on the estate is thoroughly cooled, say to +3° Celsius, we require no refrigeration car. We draw the milk from distances up to 200 kilom. and it arrives in perfect condition. The railways cannot have the task imposed upon them of keeping in good condition milk that has not been properly treated at the place of production. Apart from this, milk that has only been cooled to between 8 662 and 10 degrees can reach its destination in good condition with the aid of refrigerating cars. It is not absolutely necessary to have compressors on the estates. For the rest I accept with gratitude the proposal of Direktor Kaiser. Director Kaiser (Vienna): The objections to the use of refrigerating machines are particularly in the direction of the great cost. The farmer will always go for natural ice. If, however, he has no ice he is often placed in a forced position. The less milk there is the less will the cold plant pay. With the creation of a cold plant and a place of production there must also be suitable organisation. - Concerning the pasteurisation, I have spoken as practical man to practical men. Its dangers lie only in the connection with the storing of milk. Prof. Kirchner says in his newest book pasteurised milk should be absolutely excluded from trade by law. The boiling of milk, too, is only dangerous if it is stored for a long time. The housewife does not realise that after 36 hours the milk is bad, and uses it as long as it is Sweet. Consumers should be supplied with fresh milk and no tricks should be played with the milk. The more it is changed in its chemical and physical pro- perties the worse will it be for the consumers. I remark further that the pasteurising of the whole of the milk that is sold is by no means statutory even in Denmark. - I also acknowledge the importance of small machines for the household, but the housewife will for the most part certainly have to be content with the ice-safe. That will still be the cheapest. (Cheers.) sº President: As no one has raised any objection to the proposal of Director Kaiser, I believe that we can give the same our approval. Is the meeting in agreement therewith? (Agreement.) I declare the Proposal accepted. It will be laid before the Congress. Dr. Mary E. Pennington will have the kindness to read the proposals from the paper of Prof. Dr. S. M. Babcock, Wisconsin, Madison, on >The use of low temperatures in the production and preservation of cheddar cheese.<. Dr. Mary Pennington reads. (See p. 430.) President: Our programme is exhausted. In this section we have no more work to do. I hope that the wishes that have been expressed by the III" Commission will also be carried into effect in practical life. I beg to express the warmest thanks to all those who have read papers and assisted for their valuable work. (Cheers.) Vice-President I. A. Šimáček: I think I may speak in the name of the III" Commission, if I express our best thanks to all the Honorary Presidents, especially to Dr. v. Cramm and Dr. Koerfer. (Cheers.) I should not like to forget to thank most heartily Dr. Nübel who carried out the very tiring secretarial work. (Cheers.) The Sitting is closed. COMMISSION IV. Industrial Refrigeration. 665 Concerning the Use of low Temperatures in the Tobacco Industry. By Dr. Karl Preissecker, Finanzrat bei der k. k. Generaldirektion der österreichischen Tabakregie. — Member of the Revenue Board at the I. R. General Management of the Austrian Government Tabacco Monopoly. Low temperatures still play but a modest rôle in the tobacco industry, and at the Is". International Congress of Refrigeration in Paris the industry was not represented. If then the management of the II* International Congress of Refrigeration, in Vienna, in agreement with the representatives of the Austrian Tobacco Regie, decided to call a special subsection on >Tabacco & into existence it was due less to any information they might have concerning the application of cold in the tobacco industry, than to the hope of affording a stimulant to new work and experiment in this sphere and of thus preparing a fruitful field for the next Congress. It is certainly unnecessary to explain more fully how important for the general development of the industry is the detailed discussion of such questions among experts. I will, therefore, only report shortly upon the little that actual practice has added to my knowledge of the subject, and simultaneously briefly refer to all possibilities of other practical utilisations of low temperatures in tobacco factories. All imaginable uses for the tobacco factory will, of course, not be discussed here, but merely those which deal most directly with the actual manufacture of tobacco. Thus refrigeration is applicable: 1. In the preservation of raw tobacco and of tobacco that is half or completely manufactured; 2. For controlling the development of harmful vegetable and animal organisms in the fermented and finished tobacco; 3. For controlling the processes of fermentation in their several phases. Low temperatures will play a particularly important rôle in the preser- vation of tobacco in tropical countries. In a letter from O. Loew two dangers are mentioned to which fermented tobacco is exposed during storage in 666 tropical countries that have a damp climate. In the first place the high temperature and great humidity of the air have the effect that the fermentation does not cease when the desired aroma has been secured. The ºafter fer- mentation « becomes a continuous actual fermentation, the aroma obtained being again destroyed by oxidizing processes, and finally the extract in the tobacco decreases more and more, and the cohesion of the leaf also suffers. A second danger exists in the development of mould, which spoils the tobacco through the musty smell. Loew had opportunity, in the storage houses of the American Tobacco Company at San Juan Porto Rico, to convince himself of these evils. Yet, so far as he knows, cold is not made use of in the tobacco industry in any tropical country. In colder climates too, cold can be of use for preserving raw tobacco, matured or not yet fully matured tobacco, fermented or unfermented tobacco ; for example, on long transport. I would like to refer here to a special case that occurred in 1905 within the sphere of operation of the Austrian tobacco Regie. For some reason or other a part of the tobacco warehouse at Cattaro in Dalmatia had to be immediately emptied, and it became necessary to transfer a large quantity of immature tobacco, during decided Sirocco weather, by ship to Gravosa. The voyage was a stormy one and slow, and as a result the tobacco arrived at its destination in a condition of high fermentation. The fine colour of the goods was almost entirely lost, the quality and value being greatly diminished. Had the ship possessed suitable refrigerating equipment this would certainly not have been the case to so great an extent. I do not know if cold installations have been tried for such cases by other tobacco monopoly owners or private tobacco businesses. An incomparably greater field for the application of artificial refri- geration is open for the preservation of manufactured and partly manufactured tobacco. Lower quality material will, naturally, scarcely bear the cost of expensive apparatuses, at all events only in the case of very large quantities. Ten years ago the Austrian Tobacco Regie introduced a modest refrigeration process for preserving some valuable half manufactures. It was desired to preserve cigar wrappers, damped and uncut, or already cut to shape, unsorted or sorted, in the hot season and during an unavoidably long storage, (e.g. from the time work ceased until it began again on the following or second day) from darkening or getting soft through undesirable after-fermentation. This object is served by the Mandelj wrapper preserving apparatus. These are simple, oblong, tin cassettes which are divided into many compartments one above another on the shelves of each of which the wrappers can be deposited in shallow layers. The filled cassettes are sunk into a cool bath fed by running water. The apparatus is quite inexpensive but not very efficient especially in warm southern Austria, where the trials took place, particularly at the tobacco factory at Sacco in South Tyrol. The unsatisfactory results there led finally, in 1902 to the erection of a special cold storage building (Fig. 1) at the factory mentioned, on an American ice house system designed by Biber. 667 The lower part of this ice house (figs 2, 3 and 4) which cost about 7000 Kronen, contains the cold room a, two insulated rooms / and an anteroom o , an iron stair leads from the anteroom into the open. The foundations are of concrete and stone work, the partition walls are of larch with double casing and insulating filling. The cold room (Fig. 5) is used for storing the uncut, stripped Virginia - and Kentucky wrapper halves and the cut Virginia cigar wrappers. The former are deposited on wooden lattice trays the latter in boxes. The quantity of wrappers deposited daily in the cold room is 400–500 kg. - | - | | - - - Fig. 1. Cold storage house for tobacco at the factory at Sacco, Tyrol. The cold room is separated from the two insulated rooms by two partition walls, in each of which there is a small shutter door, which can serve for ventilation in case of need. The upper part of the building consists of the ice room (d. in Fig. 3 and 4) in the shape of a large wooden box, the enclosing walls are five fold encased and provided with double paper lining and a 45 cm thick insulating filling. The insulated floor separating the ice room from the two insulated rooms and the anteroom has a metal lined incline. Directly over the cooling room there is a metal arrangement for leading off the thaw-water. 668. It is protected above by strong transverse beams and wooden gratings. The ice is supplied through three doors on one side of the ice room. - I T] — |- — — — — — T º T a-. i = **-* r ,6 ; : ; ; a º- Á i : | 4C, | i - H i | - - - - - s E #E: - # i -- : 3. 3. # .- : - TE t --#:- + º-- *— 5- - ..J. e - É # nº- - -|- .:- - = al -- - ; É - - - - #- . i * - = 3. --- º -- | M. -- s - : -- 73° - * * * ** J– l, Fig. 3. Cross section of the tobacco cold house of the Sacco Factory. The ice house has a composition roof covered with gravel. About 1000 meterzentner of natural ice are necessary for the filling of the ice room, and the cost for this is about 700 Kronen. * Fig. 4. Longitudinal section of the tobacco cold house at the Sacco Factory. Fig. 5. Cold room at the tobacco cold house of the Sacco Factory. 669 -670 ~. In spring the thermometer shows 3° C. temperature in the cooling room; the temperature rises during the summer to 59 C. On the whole this ice house has answered fairly well and it entirely satisfies modest requirements. From the first there was no doubt that better results would be attained with it than with the Mandelj wrapper preserving apparatus. Though the method may offer but a primitive solution of the question of preserving tobacco, yet, so far as I know, the question has not yet been solved in other countries. Certainly, even here, better results may be expected from a clever application of the latest means provided by modern refrigeration. A special instance of tobacco treatment similar to that just described is the preservation of dried or fermented tobacco leaves for the purpose of preserving their condition without injury to their quality; here, too, artificial cooling might be advantageously employed, as Herr Spierer will point out in another paper. Finally, as stated by Herr J. Teller, director of the chemical laboratory of the Austrian tobacco Regie, refrigeration may also be employed for the tobacco steeping water from which extract is obtained. Besides the protection against undesirable after-fermentation there is the nced for protection against the attacks or propagation of Saprophytic germs . especially the mould producers of the Penicillium, Aspergillus, Botrytis, Mucor, Cephalothecium, Fusarium and other kinds. In this direction however, although analogous measures for their destruction or prevention have been successfully tried in other industries, e. g. in preserving bread, there are as yet no special observations or data recorded. It would in the first place be necessary to study the questions as regards the extent to which a mere reduction of temperature would hinder the development of mould, how far the cooling must be carried to ensure the best results, and how far it may be carried without affecting the quality of the tobacco. - Concerning the desirability of employing refrigeration with tobacco Herr Ingenieur Dr. Hirmke remarks that calculations based on the Schlösing ex- periments show that even severe cooling of relatively dry tobacco need not be feared. This is confirmed by experiences in Galicia. In the case of moistened tobacco that is in a suitable state for being worked, however, greater care is necessary; thus, the temperature of tobacco of about 50% moisture content may only be reduced to two or three degrees below zero, if freezing is to be avoided. - g Refrigeraton cold is also made use of for destroying injurious animal organisms in fermented tobacco and in tobacco products, As O. Loew remarks the cold is of particular effect in stopping the destructive work of a little beetle, Lasioderma serricorne Fab., which, as grub and as insect, perforates or eats into the finished cigar and often does very great damage. This use of cold has already been put into practice. Details are given in the paper by Herr Konsul Gustav Pook. 671 If the principal object of refrigeration is to prevent undesired after- fermentation, then the primary question, in an application of refrigeration during fermentation, is whether the process may be improved in certain phases by more rapidly stopping, checking or retarding the fermentation at certain stages. It is well known that larger heaps of fermenting tobacco, so soon as they arrive at a certain, empirically determined desired maximum of fermentation, are separated into Smaller x cool heaps.< (cool banks, cool layers, cool rings) and not again formed into large fermenting heaps until some length of time has elapsed which is determined by various circumstances. This operation may be repeated once or twice during the period of fermentation. It is evident that in most cases this only causes a temporary retarding of the process of fermentation. The degree of this retardation which may extend to the complete stopping or checking or interruption of the fermentation, depends chiefly upon the temperature of the air in the fermentation chamber and is pretty considerable in Galicia, in Northern Austria, where the periods of fermentation fall during the winter months; in warmer climates it will be considerably less, so that the period of cooling is longer. Apart from the economical advantage of saving time it is very doubtful, whether the artificial shortening of the cooling period leads to earlier, possibly even better development of the quality of the tobacco, in comparison with former processes. With equal scepticism do we meet the question as to whether, under Some circumstances, a complete interruption of the fermentation, easily and quickly attainable with the aid of refrigeration, works better than merely retarding it. But these are all problems which, to the best of my knowledge, have nowhere yet been theoretically or experimentally considered, though their solution is certainly of interest to the tobacco industry and might even be of practical value. Naturally these problems do not come into consideration for Turkish tobacco, or, indeed, for any cigarette tobacco, as such is completely fer- mented at one operation. In a letter Dr. W. Mayer of the Porto Rican Leaf Tobacco Co., Ca- guas, mentions that in the case of Sand leaves of poor content the method might do very good service, by employing refrigeration to avoid the too great ripening of the tobacco. I will quote his further remarks on the subject: •The market (unfortunately in Europe too) demands excessively bright, almost fawn colours. These demands we endeavour to satisfy, as also do the Deliplanters, so Mr. Hansen of the Deli-Langkat Maatschappij assures me, by giving the plants as little fertilizer, especially nitrogen, as possible, and by early morning cutting. That these leaves have then no longer too much to lose is clear, and this is best seen with the sand and lower middle leaves, which must be comparatively quickly worked to obtain any result. In this direction, naturally, cool storing might be tried and in my opinion would not be without prospect of success. A second question would be 672 § whether the colour might not be favourably influenced by cooling during fermentation. The process of the fermentation would be rendered different and the heating slower; on the other hand, however, the tobacco itself would be kept longer at the various stages of fermentation. Now, so far as I know, no-one has yet answered the question as to whether the fermentation, by being kept all day at a temperature of 55° for instance, would not end in the same way as by the method in general use. Naturally care must at the same time be taken that the cooling takes effect right at the centre of the fer- mentation heap. If it does the colours might be maintained without the quality being injured. Unfortunately this is all theory and not practice.< For the present this appeal by Mr. Mayer closes the series of already tried or still imaginable applications of refrigeration to tobacco. lt remains for the theoretical and practical expert to develop and successfully build up, by further conscientious work, everything that is of value in this series. From the present state of the application of refrigeration in the tobacco industry we may draw the following • C on clusions: 1. The application of low temperatures in the tobacco industry is of advantage a) as preventative of undesired after-fermentation in the preservation of tobacco, half or completely manufactured; 6) as a means for destroying, or hindering the development of injurious animal organisms in fermented or manufactured tobacco. 2. The following problems deserve special attention: a) In what manner can refrigeration be applied without injuring the quality of the tobacco, to preserve the dried or fermented tobacco leaves in suitable condition to be worked? 6) Can the danger of the tobacco becoming musty be avoided by making use of refrigeration ? c) Can the fermentation process be advantageously modified through suitable application of refrigeration? 4 * 673. $ The Use of Refrigeration in Destroying . Tobacco Worms. By Gustav Poock, Tobacco Manufacturer, Brazil. It is well known that there are several varieties of tobacco worms and beetles. Those found in Cuba are differently formed, being larger and longer, than those of Brazil, which frequently occur in Bahia tobacco. This harmful plague does not occur there every year to an equal extent. There are years and crops which are almost free of worms (known over there as bicho de fumo), while other years or districts are severely visited, similarly as in Germany the May bug is prevalent in some years and districts and in others scarcely occurs. That which no other had ventured to do in Brazil, the storing of to- bacco for many years, from good harvests, and the storing of cigars, finest and medium qualities — was my occupation from 1892 to 1900, in my business Poock & Cie., in Rio Grande do Sul (a seaport town in Southern Brazil, without — contrary to other well known Bahia merchants — my ever having suffered losses through worm pest. In 1900, however, traces of the tobacco worm suddenly appeared in my own raw material stock, and in my manufactured goods. The evil increased and my valuable stock (approxi- mately 1 million marks) seemed certainly lost, as the injurious pests increa- sed rapidly in the following months and years, and just the most valuable tobaccoleaves and cigars were bored and partly turned to dust. Almost despairing the idca struck me, based on the experience that in my Hamburg factory there never appeared signs of tobacco worm, that it was surely the German winter, i. e. the cold, that destroyed the pests and their eggs, and that, too, without injuring the tobacco, indeed, perhaps it was calculated to improve its quality, I made trials in the following year and subjected the infected goods periodically, with the greatest care, in freezing rooms, to artificial cold. These trials were crowned with so great a success that I was able to save the valuable stock (which I had already considered as partially valueless) from further attaacks by the year 1903, and from that time till now to protect it against the pest. 43 674 My process, for which, in consideration of the study, pains and ex- pense I had applied, the Brazilian government granted me a thankworthy patent for sole use (Decret Nr. 4151, 29th September 1904, Diario Official Nr. 237 de Rio de Janeiro of 9 October 1904, page 4715/16), consists in the, at that time, new application of artificially created cold to tobacco and its manufactures, by means of freezing rooms, or other freezing apparatus suitable for the purpose; of destroying the tobacco worm and other harmful germs in such apparatus. This application of refrigeration with the Security so gained against the tobacco worm plague then spread all over Brazil, at the same time improved the condition of the tobacco leaves, cigars and other tobacco manufactures. The application of cold for this special purpose gave the tobacco industry and trade great advantages; for, by preventing the development and spread of all injurious germs in the tobacco, it retarded the natural deterioration and often avided serious losses. - In applying this process I use freezing rooms or depôts of any system or any suitable construction, provided that they are free from moisture. In these rooms the tobacco and manufactures (cigars etc.) are subjected to the effects of long exposure to cold of at least 3–4° C. below zero, but best at 10° C. below zero. The lower the temperature, the more quickly is the desired object — the destruction of the germs of the tobacco worm and the prevention of further development, attained. .* - The trials I have conducted for many years have shown that at least 22 days and nights are necessary, if the temperature in the freezing room remains below zero during this time. The period of application is variable, since the outside temperature and the degree of development of the worm must be eonsidered. In any case the application of cold is most effective at such time as the tobacco or manufactures show first signs of the pre- sence of the germs or larvae; equally well can cold be used in every con- dition and phase of the progress of the plague, for the effect has proved Satisfactory even in cases when the worms are already out of the embryo Stage. -- - I trust that I may do a service to the whole tobacco trade with these few words of my experiences to the learned and deserving International Con- gress of Refrigeration. Perhaps it will now be discovered where artificial cold is used in the tabacco trade, whether against pests or for other purposes and with what success. I shall thankfully welcome any information and would like herewith to give an impulse to experimentation. Many dealers and factory owners, especially in hot countries can tell how great damage the worm epidemic can effect in tobacco, cigar, and cigarette stores. In Europe I have seen Turkish and Greek tobacco that was absolutely eaten through. In Rio de Janeiro, I observed but lately genuine imported cigars, just arrived fresh from Havanna, that were already bored by 675 worms. The recipient had to bear the loss and had to sell the valuable goods under cost price in fear of the danger of further rapid deterioration. I advised him to at least preserve the infected cigars in ice-safes; considering the temperature of the ice-safes not to be low enough to destroy the germs, they will at least retard development. One must consider the danger to which wholesale dealers and indu- strialists are exposed. Therefore my freezing process will be of interest and perhaps find imitation in many circles. But unfortunately the installation and management of freezing chambers is still very expensive and awkward, especially where they are most neces- sary: in tropical countries. I use only small freezing chambers (6 × 45 metres by 4.5 metres high) each of which holds about 10,000 Kilog. of tobacco in pressed bales, which quantity, in case of danger from worm would be frozen through about 22 days and then replaced by a fresh lot. The operation of these small freezing chambers I secured by connecting them with existing ice factories. Where these do not exist, as in the factory districts of the state of Bahia in Brazil, the application of cold to tobacco, because of the great quantity of raw material, would be for the present difficult to carry out for economical reasons. Fortunately last year's crop in Bahia did not suffer much from worm pest, otherwise one would perhaps have reconciled oneself to the expenditure necessary for refrigeration. That cold retards the fermenting process or stops it is known. Therefore one must choose the right moment that the quality of the tobacco may not suffer through the stopping of the fermentation. For finished, especially dry, tobacco the application of dry cold for destroying the worm germs has, in my opinion, no injurious influence on the quality. May these words induce refrigeration experts to design the cheapest possible apparatus and arrangements for the tobacco industry, preferably a cheap process for the application of dry cold air in tropical store and work rooms. Perhaps chemistry can also help. It would be of great importance, not only for tobacco, but generally; for if once the working power and the pleasure of life of man in tropical lands, as Brazil, can be increased by the application of cheaply created cold, enormous spheres open up for the turning to account of incalculable treasures, that Nature has stored up in the tropics for thousands of years. 43% 676 Cold and Moisture as Means of Preserving the Working Qualities of Tobacco Leaves. By Ch. M. Spierer (Messrs. Fratelli Allatini, Salonicco). In hot countries cold can be employed to preserve the suppleness necessary in dried of fermented tobacco leaves in order that they may be manipulated without danger, and without provoking injurious fermentation. Particularly during selection, and making up into bundles and finished bales would it be advantageous in summer to be able to cool the air of the work rooms, in which a large number of hands are employed, from 5 to 10° C., e.g. from -30° down to 20° or 25°, by using some simple apparatus. Above all, the workers would be glad to escape the enervating and depressing in- fluences of the heat, and the factory owners would find compensation for their expenses in the fact that the hands worked better in the cooler air. Naturally the air must not be dried by the cooling apparatus, for then the tobacco would become brittle. In order to satisfy the requirements of industrial working and of the tobacco trade, such an apparatus, if the necessary impregnation of the air with moisture is not effected by the lowering of the temperature alone, must both cool and moisten the air simultaneously, that is, it must, at one and the same time, assist the working ability of the hands, protect the tobacco against fermentation and increase the elasticity of the tobacco leaves. Such apparatus is already employed in the textile industry and is, also to be in- troduced into the tobaco factories of the Italian government. 677 The use of cold in the Petroleum Industry. By A. Guiselin, Ingénieur, Secretary of the International Petroleum Commission, Paris. Report upon the extraction of the paraffin contained in crude oil. Because of absence of a protective duty and the decided preference shewn by the old refiners for the importation of completely refined products, the crude petroleum refining industry tends to disappear. As the use of cold in this industry, has, up to the present, only been applied to the extraction of paraffin from the heavy oils derived from the distillation of the American crude oils, it necessarily results that these applications follow the same ten- dency. In fact there are any more paraffin refineries in France. In spite of all the objections we may have against custom tariff, allow- ing foreign imports to take the chief place in our own consumption, we should, nevertheless recognize in all fairness, that the paraffin industry has flourished, and may flourish again in France, bringing many benefits in its train. If the paraffin extracting industry does not exist in France, it is enti- rely the fault of the merchants themselves, who hold the last vestiges of the refining industry. As a matter of fact, on its entry into France, paraffin is subject to high duties. # Minimum Tariff . . . . . . . . . . . 30 francs per 100 Kgs. General Tariff . . . . . . . . . . . . 45 , , 100 , The consequence of this, in the case of paraffin imported in the crude state, is a protective duty which may be raised to'): 30 francs — 10.25 = 19.75 francs . . . . . . . Minimum Tariff 45 , — 10.25 == 34.75 , . . . . . . . General Tariff per 100 Kgs, of the products extracted. *) As the majority of petroleum importing countries are submitted to the Minimum Tariff, we can only retain the figure 19.75 francs. 678 But in spite of this important protective duty, which was still more important before 1893 and 1903, the paraffin extracting industry in France has not made the progress which was possible under these circumstances"). Let us examine what these possibilities are: The only crude oils imported up to the present in France capable of yielding paraffin, have been the American crude oils from Pennsylvania. According to the majority of experts, these oils usually contain 1°/2"/o of paraffin which may be extracted practically. As the importation of American crude oil has increased during recent years to about 150,000 tons, we may conclude, if this oil is really the Pennsylvania crude oil, that the amount of paraffin introduced into France in crude oil has increased to about 2,250,000 Kilogrammes. Let us examine the same statistics in their bearing upon CuStonS duties and we shall find with amazement that the quantities of paraffin imported into France have increased to 2,300,000 Kilogrammes”). The immediate conclusion to be drawn from this observation, is that the petrol refining industry in France, solely by the indifference of those concerned, fails to make use of a protective duty of 450,000 francs. This fact is serious enough to disclose, and shows once more that mistakes do not proceed, exclusively from the state, but also from the methods of certain manufacturing merchants who are opposed to progress. As the object of this report is not to describe the various processes in use in France, in the far too small number of petroleum industries, it will be useful for us to continue this economic explanation, by remarking on the absurdity of the fact that, not extracting the paraffin from heavy oils involves the manufacturers in increased coal expenses to produce, not the remunerative extraction of the paraffin but its complete destruction. For this purpose, in factories where crude oil coming from America (United States) is still treated, the distillation is slowed down as soon as as the paraffin oil comes over, and the oil remaining in the heater is di- stilled very slowly to produce the light oils which are distilled once more. Nevertheless, as these various distillations do not effect the complete destruction of the paraffin, and as the tarry products formed during these operations are not exactly favourable to good burning qualities in lamp oils, the products thus obtained are of an inferior quality. 4) In 1893 the difference between the customs duties for crude and refined oils was reduced 3.50 francs. In 1903 this was further reduced because of the creation of a tax on manufacture of 1.25 francs per 100 Kgs. for crude oils. *) The importation of paraffin has increased in France. to 2,277,000 Kgs. in 1907 ,, 2,058,200 ,, ,, 1908 , 2,629,000 , ,, 1909 679 Also, because of the little interest which French petroleum refiners take. in what is one of the most interesting applications of cold, there re- sults besides the loss of a customs duty of 1975 francs per 100 kg of paraffin destroyed, an excessive consumption of coal, and acid, the costly maintenance of fragile apparatus, and alterations in the lamp oil products, resulting in a decrease in value. . Such are the results of a blameworthy indifference which is unhappily an obstacle to French petroleum refineries. * Applications of cold to the better recovery of volatile extracts in petroleum refineries. After the above explanation we will proceed to study the proper me- thods of gaining new advantages, by the judicious application of a perfected system of refrigeration, for a more perfect condensation of the very vola- tile essences. This condensation is obtained in France by the circulation of the pro- ducts of distillation in coils, designed more or less accurately for the work they have to do. These coils, immersed in immense reservoirs, are cooled by means of a circulation of water, which is not methodical, and often ex- ceedingly imperfect. Under these conditions considerable losses of the es- sences or the very volatile portions, are incurred during distillation; these losses may be greatly reduced by the use of coils, better suited to the work required of them, and especially by a final refrigeration produced by the circulation of the condensed liquids while yet warm, in a coil immersed in a liquid cooled by a refrigerating machine. *. Evidently this recovery would necessitate the purchase of a refrigera- ting plant which is still thought, from force of habit, to be costly and very difficult to work. It is against this fallacy that manufactures should contend. In France the desire of avoiding the considerable losses, which may reach to 2 or 3°/, involved in the rectification of the essences, has never preoccupied the refiners. Nevertheless this 2°/, or 3"/o, of products absolu- tely lost to everybody, represents to them alone, a value far above that represented by the total cost of manual labour and reagents necessary for the work of rectification and refining. To demonstrate the importance of these losses we will take the example of a refinery of medium size, treating 10,000 tons of essences annually, and we will assume a loss of 3"/o in the work of rectification. *. At an average price of 40 francs per 100 Kgs. this loss of the very light products (gasolines) reaches every year. 10,000 × 3 × 400 = 120,000 francs. } ()0 680 Assuming that this loss could be reduced to ºl,"/, by means of a re- frigerating plant, there would remain to the prudent manufacturer 100,000 francs to pay for and maintain the refrigerating installation, neces- sary for this recovery, that is to say an installation capable of cooling through several degrees the products contained in the 100 tons treated. Suppose,however slight the quantity may be, the first 30 per cent. of the total quantity of the extracts distilled over, to be cooled from 35° –40° C to 10°C, and assuming 0.6 to be the specific heat of these ex- tracts, we should theoretically need for their cooling: - 10,000,000 × 30 × 30 × 0.6 = 54 million frigories 100 or 180,000 frigories per working day of 20 hours or 9,000 frigories per hour. I leave the question to manufacturers of refrigerating machinery. Applications of cold to the recovery of volatile extracts in places where crude oils are produced. As far as the matter has been alluded to above, evidently the problem is only of interest to refiners far away from the country of production, treating the crude products imported at great cost, and being subject to very high customs duties; let us now consider the centres of production, and we shall see that the problem is not less interesting here. On the fields of production, where the want of water is one of the most common of the difficulties, it is somewhat difficult to think of a method of cooling the crude petroleum extracted direct from the crude petroleum extracted direct from the earth by natural cold water. This dearth of water necessitates the construction of enormous con- duits, whose installation involves, and whose up-keep requires, great expen- diture of capital, which must be counted. The result of this is that the water costs very much and must be economized. It is this which obliges the manu- facturers to replace steam engines by internal combustion engines, which still need a certain quantity of water, but in reality only use an insigni- ficant proportion. This cost, if we bear in mind that the mechanical power may be obtained upon the field of production very cheaply, and if we remember that refrigerating machines may be constructed, capable of consuming very small quantities of water in their condensers, by means of arrangements similar to those used in connection with internal combustion engines; the possibility may easily be conceived of sufficiently cooling the crude oil stored up after extraction; so as to reduce in a certain measure the enor- mous loss of extract which sometimes reaches as much as 6% to 10% of the crude product. 681 An original arrangement would be one which would use the heat of its own compression in its own condenser to obtain the partial rectification of the crude oil containing the essences, while it would make use of the expansion to cool the essence produced during distillation. Another and more practical arrangement, would be to use in the con- denser, in place of water, the residue of petroleum, or crude petroleum from which the essences have been extracted. As in the preceding paragraph, after having pointed out the interest attaching to the use of cold in this branch of the petrol industry, we will leave the answer to the manufacturers, who may prove the reality of our hypotheses. Application of cold in the refining of petroleum oils. Let us now consider the possible application of cold in the different refining operations of lamp oils, leaving on one side its more special appli- cations in the manufacture of lubricating oils. All the refiners who work in petroleum oils, consisting in paraffin hydro- carbons, such as the oils of Pennsylvania and certain Galician and Rouma- nian oils, have noticed the bad influence which a high temperature has upon the treatment of oil by concentrated sulphuric acid. Above a temperature of 15° C concentrated sulphuric acid commences to react upon the hydrocarbons, giving certain complex, reddish products soluble in petroleum and which cannot be eliminated by soda ; the tarry acid formed has a tendency to remain held in suspension by the petroleum and to deposit itself very badly"). These inconveniences are very serious when certain manipulations are omitted, and especially when only a single agitator is provided to effect all the refining operations”). In order to avoid this phenomenon, the destilled oil need only be cold, as is the case in all the French refineries. This is ordinarily easy in winter, but when it is found in summer, that the refrigerators have been badly designed and that the refrigerating water used is too warm, the refiner is obliged to cool the oil before treating it with acid. In this he proceeds as follows: On the top part of the agitators most of the time is a perforated iron pipe with very small holes, in the form of spiral or coil. This pipe which is intended to throw out the washing water on to the surface of the petroleum, in the form of a small fine shower, also serves, in case of fire, to project vapour upon the surface of the flaming liquid. When the refiner wishes the petroleum oil to be treated at a tempe- rature not too much above 15°C, he makes use of this sprinkler, and * *==-a-sºº. *) These phenomena are very much in evidence when the oil undergoing refining contains products of the decomposition of cracking. *) This arrangement is working in France. 682 projects a shower upon the mass being refined, of large quantities of water, which is collected at the bottom of the agitator, so that it may be removed as fast as it comes. tº . When this operation is carried out in summer, as it frequently is, the water used is at a temperature very near 15°C, that is to say very near to that which it is desired to obtain; the result of this is that the effect ob- tained is deplorable, and that to lower the temperature of petroleum a few degrees it is necessary to lift considerable quantities of water through a height of more than 10 metres, representing an expenditure of power much greater than that which would be necessary to work an equivalent refrige- rating machine. - C on clusi on s. Such is a summary of the possible applications of Cold in the petro- leum industry; we see that in France they are interesting enough to draw the attention of manufacturers, unless they are to turn day by day into mere merchants. Moreover these applications could be made in other countries, and if, perhaps, they do not deserve to be taken into conside- ration individually, it is an indisputable fact that they would be indispensable if they could be made of in combination. *s. 683. Cold technics in connection with the Paraffin Industry in Holland and the Dutch Colonies. By E. S. Kerkhoven, Member of the Dutch Committee. Paraffin is a crystalised, mineral wax that is found in some crude oils of the Paraffin class of the constitution Cn H2n+2. It is drilled principally in Austria, in the Dutch colonies (Java, Sumatra and Borneo), the United States of North America, Canada, Roumania, Ger- many, Scotland and in Hindustan. It is used for many purposes, among others in the making of candles, matches, in electrotechnical, insulations for impregnating various materials (wood, paper, cotton etc.), for waxing floors, for laboratorial purposes etc. Paraffin may be described as a by-product of the petroleum industry. The crude oil containing paraffin is first freed of the benzine and kerosene by fractionating distillation and the resulting product generally contains the crystallised paraffin in quantities sufficient to repay its extraction. The process for this is approximately as follows: The distillate, after previous artificial cooling, is put through a filter- press, the mass obtained is subjected to hydraulic pressure and the crude paraffin thus won is “sweated», that is, any remaining oils are obtained by warming and allowed to flow off; the Sweated crude paraffin is refined and the refined paraffin eventually bleached. - The methods applied in various countries sometimes greatly differ depending upon the composition of the various sorts of oil, and upon local influences. - Cold technics play an important rôle in this industry, because a part of the paraffin only crystalises out at low temperature. The cooling of the oils containing the paraffin is effected in so-called crystallisers, many constructions of which are in use with greater or lesser success. In Europe and Asia these crystallisers are usually cooled with brine, in America, where an entirely different system is followed, appli- cation is made of the direct expansion of NHs (often in connection with ab- sorption machines). At the Dutch paraffin factories in India, in consideration of the high temperature of the cooling water (30° C) SO2 compression engines are G84 often used. The Bataafsche Petroleum Maatschappy, however, is going to erect in Borneo two NH 8-machines of 220,000 Frig. per hour. The only paraffin factory in Holland is at Amsterdam and belongs to the Dordtsche Petroleum Maatschappy". The base materials are sent to it from the factories of this firm in Java. Work is done in this factory with an SO2 cooling machine, made by the Humboldt machine building establishment at Kalk, which produces 70,000 Frig. per hour. * The Bataafsche Petroleum Maatschappy have a paraffin factory at Balik-Pappan in Borneo; the neighbouring petroleum refineries supply it with the base material. Two NHS cooling machines, of 220,000 Frig. per hour each, are employed, which were obtained from the A.-G. Wegelin and Hübner of Halle a. S. In Java at Tjepoe (Rembang) the Dordtsche Petroleum Maatschappy have a factory. This, too, is supplied with the base materials by the neigh- bouring Petroleum refineries. In this are five SO2 cooling machines, viz: One from Raoul Pictet, Paris . . . . . . . . . . . 40,000 Frig. per hour X • the Societé Genévoise, Geneva . . . . . 40.000 * X X three * * Compagnie de Fives-Lille, Lille each . 80,000 • > X. Sumatra has a paraffin factory at Pankallan-Brandan, belonging to the Bataafsche Petroleum Maatschappy. It draws its base materials from the petroleum refineries of the district. - The cooling is done by two SO2 machines of 165,000 Frig. per hour each, from the factory of A. Borsig in Tegel. Considering the fact that the Dutch Colonies occupy the third place with their petroleum products among the producers of the world, and bearing in mind that most of their pits contain paraffin, it may be said that this industry takes up an important part of their industrial labour. On the Application of artificial Cold in the Manufacture of Paraffin in Austria-Hungary. By Engineer Philipp Porges, Manager General of the Simmeringer and Brünn-Königsfelder * Maschinenfabrik. At the First International Congress for Refrigeration Industry at Paris I gave a lecture margarines) are deposited at the bottom of the oil in crystalline flakes, permeable and easily separated from the liquid part by filtration. Excessively rapid cooling would cause the oil to set in a more or less compact mass, the filtration of which would be very difficult, if not impossible. º Cotton oil begins to become turbid and to deposit its x margarines at about 120°C; to demargarinate this, it should be cooled below this tempera- ture, and the more complete the demargarination, the lower the temperature which the oil obtained can resist. In general the cooling is effected between 8° and 12"; and the proportion of x margarine « separated under these con- ditions represents 18 to 20% of the oil ; but in certain cases the demar- garination is carried further and the temperature to which it is cooled is reduced to about 4° C. There are various arrangements in use for the cooling of cotton oil. The one most frequently employed consists in cooling the oil in tubs or reservoirs of 8000 to 10,000 Kgs. capacity provided with coils in which iced water circulates, obtained either directly by means of a refrigerating machine, or by the addition of ice. Generally the circulation of the water is effected by means of a current from one reservoir to another ; in such a way as to obtain slow and progressive cooling; the water enters by the coolest vessel, leaving by the least cool one. When the reservoir at the head of the series is at the desired temperature, it is cut off in order to draw off and filter the oil which it contains, and the circulation of the water commences through the next reservoir, while a reservoir freshly char- ged with oil is added to the system. Filtration of the turbid mass is effected by filter frames or sacks in a place which is cooled in the same way as is the reservoir room itself, by ventilation of cold air coming from a refrigerator, or by a system of coils through which circulates water or some unfreezable liquid. The filtered oil represents the demargarined oil or the swinter oil & ; as for the "margarines which remains is separated from it, either by a centrifugal turbine, or by placing it on cotton cloths which are piled one upon another, and left to drain by their own weight before being submitted to a greater but moderate pressure under a load of weights, by hand, or by hydraulic pressure. - *. *- . Sometimes the cooling takes place on small masses in vessels or crystallizing dishes, put in a place kept at a low temperature. The deposit of x margarine & is removed from the crystallisers as it is formed, and placed in the filter racks arranged above the vessels, the clear oil pouring into this 45 706 latter. Finally when the oil has reached the temperature and has ceased to precipitate, it is sent to the filter press; while the margarine“ is treated as before. g In the United States and in England, an arrangement is in use which allows of more rapid and energetic cooling. The oil is introduced into a vessel containing a rotating cylinder through which circulates iced water or cold brine; the x margarines deposits itself upon the surface of the cylinder from which it is detached by a scraper, to be subsequently drained out and expelled. The turbid oil, having reached the desired temperature, is finally filtered in a filter press. - t Earth nut oil possesses, although in a less degree, the inconvenient pro- perty of becoming turbid and depositing *margarines at low temperature of about 2" or 3" C, but its demargarination is extremely difficult and im- possible practically. However slow the cooling, the oil sets in an opaque mass more or less thick, and the "margarines, thanks to the presence of cirachine separates in the form of tenuous flakes, which, on the least hand- ling, become converted into a gummy mass the filtration of which is impossible. The olive oils of certain countries, particularly those of the district of Sousse and especially of Spax in Tunis, also contain a large proportion of solid glycerides, so that the oil commences to become turbid at about 11° C., to crystallize between 9° and 10° C and to set at a temperature below this. Bertraindchaud has pro- posed to eliminate the excess of solid glycerides, perhaps 10 to 11 per cent, by cooling to about 6° to 8° C and turning the turbid mass in a centrifugal turbine. The cooling would take place in small quantities in receptacles exposed to the coolness of the night in January to February or immersed in iced water at any other time of the year. The demargarination of hoof oils, cod liver oil, sperm oil and various cetaceous or fish oils is effected by the same methods, but as it is generally practiced in northern countries, such as Norway, Sweden and Scotland, it is often accomplished only in the cold season and without the aid of arti- ficial cooling. Suet and Lard Refineries, Factories of Margarine and Edible Fats. In these various industries the applications of cold are numerous. Suet Refineries, In refineries for edible Suet, the Suet in pieces which cannot be melted immediately is preserved by being hung upon hooks in cool, dry and airy places, kept cool by ventilation of cold air coming from a refrigerator. When it is placed in the most favourable conditions for preservation, the suet becomes hard and dry, which facilitates its sub- sequent grinding. * These very suets before being ground and melted are washed with very cold water, often artificially cooled, especially in summer, and when 707 the suets treated are fresh and have not passed into the drying room, the washing with iced water cleaning them, as well as giving them the necessary consistency for grinding. - The manufacture of olio-margarine and of suet compressed in moulds both equally admit of the use of cold. . The first liquid, melted suet for choice, is left for crystallisiation in small quantities in vessels put in places at a temperature of 25° to 30°C The suet being poured off at 45° C., it is necessary, above all in summer after the suet is poured out, to bring the temperature of the crystallising rooms between 25° and 30% C, which is effected by means of fresh air ventilation or by artificial cooling, according to the Season. The crystalline mass is enclosed in cloth and slowly squeezed out by band or hydraulic presses at a temperature of about 25°C. The manufacture of suet oil is carried out in the same way with this difference: that pressure is applied at a much lower temperature, which necessitates cooling the places where it is carried out. Lard refineries. In lard refineries the same applications are found; the cooling of the drying rooms where the material is preserved, cooling the water which serves to wash it. Besides this, cold is used for the solidi- fication of edible lard, and the crystallisation of lard intended to be divided by pressure into x stearine « or compressed lard and solein's or oil of lard. The solidification of edible lard should be effected rapidly, and while the mass is being agitated, in order to obtain a more homogeneous and whiter product. In the large installations set up in the American packing houses (Chicago), the solidification is effected by means of refrigerating cylinders called lard coolers. The liquid lard is distributed by means of a spray upon the surface of one or two horizontal cylinders through which passes the iced water or refrigerated brine ; these cylinders move with a slow rotary motion, so that the lard contained becomes solidified on the outside of the cylinder or cylinders, forming a thin even layer which is detached by a Scraper and made to fall into a hopper. The European installations, which are of less importance use the same arrangement reduced to a single cylinder. Or again they use simple churns or beaters having double walls through which circulates iced water or refri- gerated brine. An agitator formed by a frame fitting the shape of the churn, stirs up the mass and continuously scrapes the interior surface in order to remove the solidified lard. As for the preparation of lard oil and compressed lard, analagous to that of olio margarine and compressed suet, it admits of the slow cooling of the lard at temperatutus of 8° to 12°C in winter and of 12° to 150 C in summer; crystallisation takes place in a granular form, in small quantities in vessels or crystalisers, left in a place cooled to the said temperature by ventilation with cold air or by coils of pipes through which circulate iced * 708 water or cold brine. The crystalised mass is then wrapped up in cloths and in this condition submitted to a moderate pressure in a cool place. The temperature of the pressing room depends on the point of solidification of the lard oil which it is desired to obtain and varies between 09 and 10° C. Margarine factories. In margarine factories, besides its special appli- cations in the melting process, cold is used in various stages of the manu- facture. - The milk used in this is kept until it is ready for use in ice boxes or cold rooms or in receptacles having hollow walls filled with ice or through which iced water circulates, so as to prevent it changing. Also the most common practice is to pasteurise it at 75°C and after this operation, to cool it rapidly below 149 C by placing it in refrigerators either having double walls or pipes through which circulates iced water or cold brine. The cream separated from the milk by centrifugal force, is likewise preserved in iced boxes or cold rooms. The churning of the milk and the fatty matter is carried out at a temperature of 259 to 40°C; the best products and the best keeping quali- ties are obtained at a low temperature, at about 25°C; so the materials and the place where the churning is done are cooled down to the said temperature if there is need, according to the Season. The churns themselves are provided with hollow walls permitting a circulation of cold water. The precipitation of the emulsion derived from churning represents one of the most important applications of cold ; and it is effected by dif- ferent methods and by means of various arrangements. r The most simple process consists in removing the liquid emulsion in a vessel or flat basin while crushed ice is dropped into it. Another method, the one most frequently employed, consists in turning upon the emulsion a strong jet of water, of milk or of whey cooled to about 0°C by ice or by means of a refrigerating machine. Solidification thus takes place immedia- tely in the form of a soft clotted mass, from which the whey separates easily. Among arrangements based upon this principle must be mentioned those of H. F. Peterson (D. R. P. 62.259, 1891), R. Backhaus (D. R. P. 88,522, 1895), L. C. Uhlenbrock (D. R. P. 99.470, 1896). A third process devised by Scheffel (D. R. P. 116.755, 1899) consists in cooling the emulsion in a closed vessel by precipitation with cold com- pressed air. A last system produces solidification by agitation or circulation in contact with cold surfaces, without the refrigerating liquid mixing with the emulsion; which also does away with the washing of the mass. Among the arrangements set up on this principle that of Donkers (D. R. P. 101.207, 1898) includes a plain horizontal surface cooled by circu- lation of cold liquid (brine, whey, milk etc.) and a little truck moving from one end to another over the surface. The little truck is filled with the emulsion and lets this pour out, where upon, it is exposed and is solidified 709 on the cold surface in a thin layer; when the truck is empty it is sent back to its starting point, then despatched again, but on this journey a detachable Scraper which it carries at its base, scrapes up the solid layer and drives it into the grinders. - Another arrangement by H. & E. Schou (brevet francais 379,905, D. R. P. 197.004, 1896) resembles that used in the solidification of lard; double horizontal rotating cylinders, cooled by an internal circulation of Cold liquid and upon which the emulsion to be solidified is distributed by sprays; this emulsion sets in a thin layer on the surface of the cylinders whence a Scraper detaches it and makes it fall into a hopper. In other appa- rati practically analagous to this a horizontal rotating cylinder, cooled either by ice contained in its double wall (Mollinger); or by a refrigerated liquid (Ekenberg Norwegian Patent 14058) plunges into the vessel containing the emulsion and in rotation gathers this in a thin layer which sets on the surface. Margarine solidified by the above methods is then left for some time in contact with iced water in order to make it firmer for ultimate work ng. Besides these special applications, cold is used in margarine facto ies in a general way to keep the work rooms and stores at a low temperature So as to prevent alteration in the products. Manufactures of Alimentary fats: In the manufacture of alimentary fats other than margarine, such as artificial lard, * compounds, etc. which are simply mixtures of fatty sub- stances, use is made of cold for the solidification of these mixtures, the arrangements in use are the same as those adopted for lard. Butter factories. The applications of cold to the manufacture of butter are numerous but the study of them, which concerns the work of another section, cannot be undertaken here. Vegetable butter factories. Vegetable butters, the manufacture of which, has made such consi- derable progress during recent years, also allow of some applications of cold; it is well known that under the name of vegetable butters are specially meant cocoanut butter, and palm butter, and the mixed product derived therefrom. These butters are delivered for consumption either in casks or tubs or metal cases or in moulded cakes wrapped simply in waxed or Sulphu- rised paper. The solidification of the blocks or cakes is effected in most factories by the artificial refrigeration of the products. In certain installations the cooling of the boxes or moulds filled with liquid butter is effected by leaving them in a room cooled below 12° to 710 15° C, the boxes or moulds are placed upon little trucks having shelves which are introduced into the rooms and removed after solidification. Some- times the cooling is effected in a cold tunnel or passage, through which the products pass automatically at a rate regulated so that solidification is com- plete on their coming out; in this case the boxes or moulds are placed on shelved trucks drawn by an endless rack or belt, or some other similar device, or directly on an endless belt. The refrigeration of the rooms or tunnels is effected by means of ventilation with cold air coming from a refrigerator, or by coils through which circulates a cold liquid. Lastly, certain factories use crystallising vessels 15 to 20 metres long in which the boxes or moulds, resting upon an endless belt, moving very slowly, are immersed for three quarters of their volume in a liquid cooled to 50 to 100 C. - , The turning out of the cakes or blocks is effected by knocking the moulds when turned upside down upon a table. The filling and turning out of the moulds necessitates considerable work which it is sought to reduce by the use of refrigerating machines, which have, besides, the advantage of accelerating solidification. Among these machines may be mentioned that of Berkovitz and Oster- loh (D. R. P. 199,714, 1906 and especially the refrigerators used for the soli- dification of Soap in cakes and bars, and which are described further on (Jabi, Klumpp, Schrauth etc.) These refrigerators generally act as filter presses, through the walls and framework of which passes a refrigerating liquid, the spaces being filled with the liquid butter to be solidified. Lastly, some other systems accomplish the solidification in the paper coverings which constitute the wrapping of the cakes, which avoids this manipulation; such are the arrangements of J. E. de Bruyn (D. R. P. 106.367, 1908). Y. ~. The vegetable butter industry requires an additional operation which sometimes makes use of cold, this operation analagous to that in the case of oleomargarine and compressed suet, consists in separating out the liquid solid glycerides by pressure in order to obtain a product having a high melting point, reaching 309 or 359 C. *. - Cocoanut and palmoils, whether natural or not, are left to solidify in order to obtain crystallisation as plenteously as possible; the temperature of the crystallising rooms is kept at about 20° to 22° C for cocoanut oil and at 249 to 25° C for palm oil, having recourse if necessary in the warm season to ventilation by cold air, to circulation of cold water, or of a refri- gerating liquid in coils. --- Lastly, cold is used in vegetable butter industries in order to lower the temperature in summer of the places intended for the stock of the pro- ducts ready for consumption. ** T11 Soap factories. The manufacture of certain soft soaps, much esteemed in Germany, involves the use of cold. These soaps called grainy soap (Naturkorn, schmierseife) are characterized by their grainy aspect, due to the slow for- mation of crystals of palmitate and stearates in the clear mass of oleate or linoleate. This crystallisation proceeds with time during which the Soap is left in tubs in dry and cool cellars of which the average temperature does not exceed 10° to 16° C. Generally airing or ventilation of these cellars with fresh night air is enough, even in summer, to maintain this temperature and use is rarely made of any other means of cooling. The solidification of hard soaps has for a long time been accomplish- ed entirely by natural cooling, by leaving the warm liquid soap in flat paved or cemented areas, divided into compartments by partitions of masonry or wood, or by moveable screens formed of a frame with detach- able lateral panels. This system necessitates large areas, a relatively long period of solidi- fication, especially in summer, and hence accumulation of products and locking up of capital; it has been sought to avoid these inconveniences also by rapid cooling by means of refrigerating machinery with circulation of cold water. Some of these machines are arranged to solidify the soap in sheets, others in bars, or even in cakes of a suitable size, which reduces or gets rid of, the hand labour and waste, which are involved by the cut- ting up of the soap poured into trays. * The number of refrigerating machines proposed for soap in recent years is considerable, but the majority may be divided into types from which they only differ in constructional details. It will be enough then just to briefly describe the principal types and to make mention of the other machines. The machines of Leindorfer, de Schnetzer-Schicht (D. R. P. 104.505, 144.108, 135,079) of Talwande Fréres and Douault (brevet francais 344,006 etc.); work on thesprinciple of pouring out of moulds; the warm liquid soap is poured into tubes of Suitable section, cooled by an external circulation of water, and when solidification is finished, the bars of soap are pushed out of the tubes by pistons. The Klumpp Refrigerating Press (D. R. P. 126.609, 140.846. 211.624) is made up of a Series of parts, resembling a completely closed horizontal copy press, through the hollow sides and the separating partitions of which cold water circulates; the fluid soap, as soon as it has solidified, is strongly compressed by hand or hydraulic pressure. The Jacobi press (D. R. P. 194.683, 202.710, 208.590) is based upon the principle of the filter press. Cold water circulates through the hollow plates and the spaces are filled with the liquid soap to be solidified, coming from a reservoir in which a light pressure is exerted (4 or 5 kgs.), by air com- pressed by a pump. 712 The Schrauth Refrigerator (D.R.P. 186,731, 189,024, 198.112, 202.374) and most others are similar in arrangement, differing only in some details; such are the Weber, Seeländer and Steck (D. R. P. 198.865 and 201426), Count Harzer (D. R. P. 201710), J. Hauff, W. Rivoir (D. R. P. 17050190) Rost machines etc. - - - - Lastly, among other machines working on different principles must be mentioned those of G. Klinger (D. R. P. 204,166) of the Krefelder Seifen- fabrik, Stockhauser and Traiser (D. R. P. 196.945) etc. It should be pointed out that artificial refrigeration is blamed for changing the texture and appearance of soap and especially for destroying the crystallisiation produced by ,watering” especially in soaps rich in fatty acids; soap thus solidified also tends to become greasy and darker with age; finally these machine consume a large quantity of water which may however be reduced by refrigeration by means of a refrigerating machine, and their cost is rather high for a relatively small production. In fact their use has only spread a little in Germany and little or not at all in England and France, who take, nervetheless, the first place in the soap making industry, both in the importance of their factories and in the quality of their products. Long before artificial refrigeration was applied to the solidification of household soaps in cakes and bars, it was used for the solidification of pastes of soap, intended for the preparation of toilet soaps, by grinding while cold with perfumes and colours, rolling, twisting etc. In this manufacture the soap should be reduced to shavings in order to be submitted to dessiciation in a stove. In order to avoid solidification of the soap in cake, the breaking up of the cakes into shavings and the manual labour' resulting from this, Des Cressonières Frères in 1890 D. R. P. 550.65), proposed a machine consisting of a number of parallel hollow cylinders circulating cold water, the first of which, partly immersed in liquid soap contained in a hopper, takes up a thin coating which then becomes cooled, solidified and rolled by passing between the successive cylinders. - Another device, due to Benger Fréres, consists in a hopper distri- buting the paste in a thin layer upon a metallic belt, being taken up and cooled by a hollow drum circulating cold water. Other similar machines have been made by J. Lehmann, W. Rivoir etc. Toilet Soap obtained by artificial cooling in thin sheets has a glassy transparent appearance, while soap which has cooled by itself and broken up into chips forms an opaque mass having a more greasy appearance; while it is generally harder it does not lather so easily. To avoid these inconveniences, and benefit from the advantages of artificial cooling, it has been proposed to solidify the paste of soap in the refrigerating machines described above, in very thin sheets of half a centimetre in thickness, which are then broken up into chips for dessication. 713 Stearine and Candle Factories. Stearine factories use cold to lower the temperature of the crystallising rooms, and the cold pressing of the fatty acids, and for the recovery of , stearine“ and poleins". The crystallisation of fatty acids should be carried out slowly at a temperature of about 25° C; as the liquid mass is poured out at a tempera- ture of from 40° to 45° C, the temperature of the crystallising room should be rapidly lowered to 25°C, which is effected by ventilation with cold air. The cold pressure of the cakes of fatty acids should be carried out at a temperature between 15° and 20°C, and the pressing room is kept at this temperature during the warm season, if necessary by ventilation with cold air. * Dubovitz has recently suggested submitting the cakes of fatty acids, before pressing, to a preliminary cooling to 7° C. His experiments have proved that in working thus, the olein pressed out is not above 9" to 10°C, then it reaches 16° to 19°C by continuous compression. Crystallisation takes place as usual at a temperature of 20° to 25°C, then the cakes, coming out of the moulds, are piled one upon the other, in such a way as to give access to air all around, in a place cooled to 7° C. The cooling should be slow; it is effected either by ventilation of air coming from a refrigerator or by means of system of coils through which circulates a cold liquid. The room where the pressure of the moulds is carried on should naturally be kept at a temperature lower than usual, at about 10° C. - Olein, pressed out cold from the cakes of fatty acids, still contained a proportion of , stearine“ more or less considerable according to the season, the method of working and the care taken; this proportion reaches from 15 to 30 per cent. In order to recover this stearine“ the olein is cooled down to 10° C, the solid acids crystallise out and are separated from the liquid Olein by filtration or centrifugal force. The cooling of the oleins takes place in various ways and by various appliances. It should be carried out slowly so as to obtain plenty of crystals, easily separated from the olein. In some stearine factories the olein is contained in large reservoirs or flat vessels in a place cooled to 10° to 15°C; in others the cooling is effected by an injection of compressed air into the mass of the olein. Among the numerous arrangements suggested we must mention the appliances of: Proux and Engelhardt, Beilby, Bela Lach, Petit Frères, Zuc- cari, Kind (D. R. P. 30,898, 1884) of Smith (D. R. P. 32.012) of Misseuer (D. R. P. 16,029, 1881) etc. The Droux and Engelhardt apparatus consist of a series of cylindrical receptacles having double walls through which circulates a cold liquid, pro- 714 vided with an agitator; the olein circulates in one or other of the recep- tacles until cooling, facilitated by agitation, is completed. Beilby's apparatus is similar, and consists in ten flat vessels having double walls and an agitating propeller. The Bela Lach apparatus only differs from that of Droux in some constructional details. - The following apparati effect rapid cooling in a thin layer. The Petit Frères apparatus consists in a rotating drum having double . walls through which circulates the refrigerating liquid; this drum dips in a hopper containing oleic acid, and in its movement takes up a thin layer of olein which is cooled and deposits stearine, which is removed by a scraper causing it to fall into a vessel underneath. The Zuccani apparatus is formed by an insulated receptacle containing oleic acid and in which there is a hollow wooden ring, through which passes a refrigerating liquid. A central shaft, having a rotating movement, carries two scrapers which scrape off the crystals deposited upon the interior and exterior surfaces of the ring, and separate them from the mass; this is finally removed when it deposits no more crystals. Smith's apparatus consists of a series of three cylinders one upon the other, between which runs an endless belt, made of felt; the whole system is placed in a cold room. The olein is projected in a shower upon the belt, and the crystals solidifying upon its surface are separated from the liquid part by the pressure to which the belt is submitted between the cylinders. The other appliances resemble the refrigerated cylinders employed for the solidification of lard. The stearine factory involves a last application of cold in the moulding of candles; the moulds containing the fatty acids are generally cooled ex- ternally by a circulation of cold water, in order to accelerate Solidification and to facilitate moulding. The temperature of the cooling water depends upon the composition of the stuff poured in; it is a good thing for it to be low and for solidification to take place from the beginning. For candles having a low melting point or containing paraffin, the final temperature should be as low as possible, and for certain kinds of paraffin candles it should not exceed 10" C, it might even go so low as 5" to 6°C to obtain a fine glaze. Certain American machines arranged for the pouring in of substances of a high melting point, accomplish the cooling of the moulds by the circulation or injection of cold air. As may be seen from this summary, the various industries working in fatty substances involve a considerable number of applications of cold, and this is either produced naturally by the temperature of the air or water, or artificially by using ice or refrigerating machinery. 715 Modern industry, demanding, as it does, rapid and intensive production can no longer fail to be interested in means allowing economy of time, space and hand labour, and in this way cold of all description offers soluti- ons of this economic problem to the industries which we have just reviewed; and for those of them which deal with alimentary products. it allows them to improve or preserve the qualities of these products, and thus to benefit by the greater value which results therefrom. 716 The application of cold in the Camphor Industry. By M. Guiselin, Paris. Cold has long been employed in the manufacture of organic sub- stances, and there are certain reactions which are only obtainable by this IIlêa.11S. In one of the first phases of the synthetical manufacture of camphor the transformation of an essence of turpentine into solid hydrochloride of pinene, we are also obliged to make use of a low temperature. The action of dry gaseous hydrochloric acid upon an essence of turpentine results (1) in removing thermal energy from the turpentine (2). In modifying its mole- cular structure, and in transforming it into bornylene, a carbon compound whose composition is identical with that of camphor. This action, being endothermic produces a certain amount of heat, which, if it is not immediately absorbed, raises the temperature of the reac- ting masses proportionately to their respective specific heats. But, under the influence of heat the molecules of turpentine, being easily effected by heat, undergo new molecular changes, and may form isomeric compounds of the turpentine originally put in. Thus pinene and bornylene, divolent turpentine, which are liable to give solid chlorides, are transformed, under the influence of heat, by a mi- gration of their internal molecules and by changes in the connections of the atoms to one another, into quadrivalent turpentine, such as dipentene, limonine and sylvestrine, which form in combination with hydrochlorid acid liquid ethers whose structures are totally different from that of camphor, and which cannot be converted into that Substance. It can be seen, then, what an important part heat plays in Such a re- action. - According to Berthelot, hydrochloric acid acting upon a certain weight of essence of turpentine, releases 15 calories, and acting upon an equivalent molecular weight of a quadrivalent turpentine such “as dipentine, it releases 58 calories. If then, the calories produced in the first phase of the formation of the hydrochloric ether of pinene, are not absorbed by refrigeration, this heat would affect the pinene and turpentine, causing at least a partial decom- 717 position into dipentene, by an isomeric modification. The hydrochloric acid gas, etherizing this dipentene, would release in its turn for the same molecular weight, 58 calories, which, if not immediately absorbed, would cause the almost immediate modification of more pinene into quadrivalent turpentine, and so on. It can easily be understood that, if the mass of the turpentine upon which the Ieaction is being carried out is not cooled at all at the commencement of operations, and if no precautions are taken for the calories produced by etherification to be absorbed as fast as they are produced, instead of being transformed into solid hydrochloride of bornylene, the greater part of the pinene would be transformed into a useless quadrivalent hydrochloride of turpentine: - The use of cold, in such a process is then absolutely indispensable and the capacity of the ice machines in frigories should at least equal the production of heat in calories, as given in Berthelots figures, according to the amount of turpentine treated per unit of time. For 100 kilogrammes of essence per hour which we will suppose to be transformed into solid hydrochloride of pinene, or better into chlorate of bornylene, 119,000 calories would be produced, assuming that no part is transformed into dipentene: The ice machines installed should be of a power sufficient to absorb these 119 000 calories, while maintaining the reacting mass at the desired temperature, which is 15° C in practice. If these conditions are carefully observed, the yield of solid hydro- chloride of pinene, which, at the ordinary temperature, and when the heat is not absorbed, never exceed 35%, would in this case reach from 100% to 110% of the essence used. -- The synthetical manufacture of camphor appears to be impossible wit- hout refrigerating apparatus. - 718 The Use of Cold in the Chemical - and Physical Industries. By A. Guiselin, Engineer, Paris. If you will kindly refer to the voluminous publications of the I* Inter- national Cold Congress and open them at the page reserved for the Chemical Industries, you will readily understand the legitimate feelings which led me to hesitate for a few instants when, on the initiative of Our learned president, Armand Gautier, the Cold Association did me the honour of proposing me as Chairman in connexión with the special applications of Cold in the Phy- sical and Chemical Industries. - - The mission which I accepted proved indeed, in its early stages, to be excessively arduous. Very few of the numerous letters I sent to friends ergaged in Industry elicited replies, and those addressed to manufacturers, personally unknown to me, were even less successful. It was about this time that I had an interview with our sympathetic and devoted General Secretary, M. de Love r do, who communicated to me the very interesting statistics which he had had the opportunity of veri- fying himself during the ceaseless struggle in which he was engaged at the commencement of the Organization of the I* International Cold Congress. M. de Love r do assured me that, in the case of a question of pos- sible interest, the proportion of replies to letters sent out was generally from 6 to 10°lo, but that in other cases, hardly 1°/o of replies might be expected. - Partly reassured by this advice of a veteran, I decided to recommence the experiment, and it was at this time that the idea occurred to me, thanks to which, Ladies and Gentlemen, I have been able to obtain, from the most varied sources, 15 complete reports and a quantity of most interesting information concerning 15 other Industries capable of utilizing the advantages of Cold. This idea occurred to me after the receipt of a very interesting letter, which may be considered as the starting point of the whole enquiry in which I have since been engaged. 719 Having ascertained that Cold could be utilized in the Tanning Industry and having applied successively to the President of the Leather & Skins Association and to the Managing Director of the Journal of the Leather Industry, I was soon edified, first by the absence of any reply from the President of the Association and secondly by the letter of the Director of the Leather Journal, which commenced as follows: »Sir, You must have been misinformed, for our Journal has never occu- pied itself with the use of cūld which does not interest our Corporations, and closed with the following astonishing information : »Like everyone else we are well aware that a temperature of 29 below zero is sufficient to prevent the putrefaction of fresh skins; but this process could hardly be adopted, save by tanners who wished to preserve the skins before treatment, or by those who desired to avoid salting the skins imported from America. Nöw this operatién would be in any case necessary, for immediately after disembarkment the skins would have to be salted at the Port before being dispatched to the tanning centres, even if these centres could be reached in less than 2 days by rail. The propo- sition is therefore of no interest and it is on that account that skins are still salted in North and South America.< It follows therefore that the tanners were so ill informed that they were ignorant of the existence in France and elsewhere of refrigerating cars doing away with the necessity of salting in the ports. But let us pass to the end of the letter. "We are also aware that sheepskins tanned with sumach, when exposed to dry, are not deteriorated by frost; but Ön the contrary, improve, becoming whiter and more appreciated for dyeing in light tints.< - You will admit that after such revelations it is difficult to express our astonishment otherwise than to regret the state of mind of a great Industry struggling with the difficulties involved in preserving fresh skins and which, while recognizing the advantages of intense cold in the tanning of certain skins, replies : *Sir, the application of cold does not interest our corporation. < But let us proceed to the end of this enquiry, which unfortunately I have not had the leisure to prosecute to the same extent as many others, mainly through lack of time. Politeness necessitating a reply to the above letter, I wrote imme- diately to the journalist in question expressing my surprise, and pointing out to him the existence of ships with cold chambers capable of trans- porting fresh skins, and of special railway cars for the same purpose. * x * x A. 72O Without laying too much stress on the disdain of the use of cold shown by the tanners, I took the liberty of asking him to specify the advantages accruing from the tanning of fresh skins; this is his reply: »Sir, We have received your letter of the . . . . . . . A skin fresh from the Slaughter-House gives less work than a salted one, because it is sufficient for the first to be steeped in rapidly running water in order to remove the blood and foreign matter, whilst the Salted skin requires a much longer steeping to get rid of the salt and make it fresh again, and it has afterwards to be treated once or twice more than the fresh skin — — «. Ladies and Gentleman, you have only to draw the conclusion. This letter was a revelation to me. ---. - 3. After this instance I was able, generally speaking, to judge by com- parison and to infer that what happened on a small scale in the tanning Industry might very well occur on a large one in the Chemical Industry. In short the use of cold was not overlooked, it was simply despised and neglected in consequence of an apprehension, excessively singular, but much spread among conservative manufacturers, in respect of technical novelties. It was necessary to approach the subject from another side, which I did. I no longer asked manufacturers what they thought of the application of cold, but modified my question, and with many circumlocutions, in order not to frighten them, I first narrated the great progress achieved in other Industries and then continued, generally in the following manner: »Sir, It is not my desire to penetrate the secrets of your industry, but after what I have just said you will understand, as I do, what universal benefits may result from an extension of this new branch of human activity. Up to now the application of cold has been almost exclusively limi- ted to the preservation of alimentary produce, and the makers of refrige- rating machinery have concentrated their efforts mainly in this direction. Doubtless the introduction on the market of machines capable of a wider utilization will attract the attention of manufacturers and lead them to make machinery better adapted to the needs of the Chemical Industry and furnishing in consequence cold at a lower cost per unit.< *You will I am sure admit that, to encourage these researches, it is absolutely necessary to show the Engineering Industry all the advantages it is entitled to claim in recompense of its efforts, and that is I hope the end which will be attained at the next Vienna Congress. 721 I therefore ask you, Sir, to be kind enough to give me briefly your views as to the advantages which might be secured through the use of Cold in your Industry, and to facilitate your task I would ask you to assume for a moment that the units of cold supplied to you would be so cheap as to represent but an insignificant part of the expense incurred in their use. . . . . K. - In other words, as I should speak to friends, "My dear. . . . Suppose for an instant that I offered you cold for nothing; what use would you make of it in your Works?. - Well, Ladies and Gentlemen, it was by proceeding in this manner that I have been able to obtain the greater part of the information which has been communicated to you, partly in the form of a report which I will deal with as rapidly as possible. - * Contrary to custom, the main interest of the work of our Section is not in the conscientious study of what has been achieved in the past, but more especially in the anticipation of what may happen in the future. - Messrs. Jean card & S a tie were the first to respond to the appeal I made to the Chemical Industries. They at once appreciated the impor- tance of the question I had raised, and I may say that their report is a model of the kind. --- ». . . . . . The use of Cold in the manufacture of perfumery is at present very limited.<, said they, but that will not prevent us from revie- wing all the advantages which our Industry might secure by the use of Cold K. »They add that if the applications are of small importance, it may be useful to study the different processes of the Industry which might be improved by the use of Cold. The present note is not concerned with prophecies, but simply endeavours to submit a series of problems of interest to the perfume Industry.* That is the manner in which all manufacturers should speak, and if I am fortunate enough to make more disciples, that is in very simple language the whole of the vast general problem which I am taking the li- berty of discussing to-day in your presence. You will, I trust, allow me to thank Messrs. Jean card & Sati é in the name of all of you, and especially of the makers of refrigerating machinery. ~. -- - While on the subject of perfumes, let us say a few words concerning of artificial perfumery. - In his report on the making of artificial perfumery, Mr. J. D up on t shows us again the numerous applications of Cold to bring about in the solutions, the settling of the fats dissolved by means of solvents, or to se- parate by crystallization the constituents of most essential oils. 46 722 Anethol . . . . . . . by cooling the essences of aniseed and badian, Menthol . . . . . . . X X) X). X) • Japanese Mint. Safrol . . . . . . . . X) X X) X » fractions of high density of essence of camphor. Methylnonylacetone > X) Yº X » Rue. Leugenol . . . . . . X X X X * Cloves. Mr. Dup on t, who like all his colleagues, has frequently utilized Cold, draws the attention of all manufacturers to the use of this agent, especially when the Industry in question has its origin in the working on a large Scale of processes evolved in the laboratory. Let us turn our attention to One of these Laboratory Industries and speak of artificial camphor. In his interesting report on the manufacture of artificial camphor, Mr. André Dub O S c concludes that it is absolutely necessary to utilize cold in the manufacture of this product, which promises to have a great future. The importance of cold is so great that by its means it is possible to obtain yields exceeding 100% of the Essence of Turpentine used, whereas the yield hardly attains 35°/o when the reaction takes place at the normal temperature. Camphor is used in the manufacture of celluloid; let us pass to the latter. Another friend of mine, Manager of one of the most important Cellu- loid Works in France, declared, like the majority of his industrial collea- gues, that a use for cold had yet to be found in his Industry. However, he adds. "Cold might be utilized to condense the alcohol and camphor fumes which are given off abundantly during the rolling of the celluloid. These fumes, which are now lost, might possibly be condensed.< This is the language of an intelligent manufacturer, learned and ingenious, whose economical and methodical qualities I had been able to appreciate at school. After that, may I be allowed to judge the others? * Questioned regarding the utilization of cold in the colluloid Industry, M. Be r n a d a c replies as follows: » As a matter of fact, I do not see a priori what use we could make of cold in our Industry. However it would perhaps be of advantage during the hot season to cool the blocks of celluloid a little more ra- pidly, by some other process than that at present employed, which con- sists in directing a stream of water, obtained from the Works well, on to the blocks. The blocks measure 135 × 0.66)× 0.12 to 0-15 — they weigh 100 kg and are soldered to cast iron plates of the same area, 8 to 10 cm thick, weighing 800 kgs. The blocks take 10 to 12 hours to cool by this process, thus rendering a costly plant idle for a length of time which might easily be reduced. This is a striking and typical example of a manufacturer recognizing the utility of cold in his Industy in order to please a friend who is endea- vouring to obtain reports. 723 I propose henceforth to continue my researches in this manner, which bids fair to furnish a considerable number of problems for solution. To begin, let me allude to those pointed out by Mr. Ott end a hl. Here again I am glad to be able to draw the attention of those present to the extent to which routine may become unfortunate and dangerous, and I thank my friend Otten dahl for having given to his report the form of a comprehensive criticism, showing to what a degree certain manu- facturers carry their imprudence and carelessness. In the Explosives Industry the profits are considerable, and one cannot therefore admit that the neglect of the use of cold is due to a lack of capital, or a reluctance to lock it up in an uncertain business. The ever present dangers would, one would think, lead to reflexion, but, as Mr. Otten d a hl remarks, nothing of the kind occurs, in spite of the danger and the certainty of a superior yield, the old methods are still followed, although the obstruction of a serpentine or the failure of a well during nitrification, might lead to the most terrible disasters. The task I have undertaken of convincing the Chemical Industries of the utility of cold, has therefore not been so easy as might be believed a priori, for the certainty of doing better, and avoiding danger, has not in- duced certain rich manufacturers to improve their plants. Do you wish for further instances? In a very interesting report, which I invite you to peruse carefully, M. Bout a ric discusses very thoroughly the different processes of gum extraction and the making of derived products. If in his statement he does not often speak of the use of cold, he expresses his regret at its neglect, and with much care and precision points out on several occasions the advantages to be derived from opportune refrigeration. - It is moreover in this way that one must proceed in dealing with all industries capable of obtaining improved results by the use of cold. To conclude, M. B out a ric describes an apparatus for recovering to a great extent the solvent contained in the solutions of rubber used in the manufacture of rubbered cloth. This apparatus, in reality very simple, could evidently be utilized in a number of other industries, especially, as we shall see later, to recover the fumes of alcohol and camphor given off in abun- dance during the rolling of celluloid. A further instance. - M. Cavalier, in his very interesting communication, regrets that his Industry, like many others, fails to utilize cold for the conservation of the per- ishable matter forming the raw material in the manufacture of glue and gelatine. Further, he points out a fact met with in most of the Chemical Indu- stries, i. e. that the working results are much better in winter than in summer, because it is much easier in winter to heat the Work-shops and the material, and keep them at a fixed temperature, than to reduce the temperature in summer to this level by means of well water, more or less 46% 724 fresh, or ice bought at a high price on the spot. I leave you to study in the original report the numerous advantages which this Industry can secure by the use of cold. I wish however to draw your attention to the impor- tance which dry cold air may have in connexion with the proper drying of gelatine, although, for reasons of economy, I strongly recommend manu- facturers to utilize concurrently with the ordinary methods of drying by cold those which have just been proposed by Messrs. Daub in e- & Roy, which are worthy of notice and very attentive study. wº In these two great Industries cold is apparently used, but with so much secrecy that I have been unable to violate the sanctuary. I do not however despair of success; not in order to appropriate what belongs to others, but for the general benefit. * & - - , , , - It is quite evident that cold may be profitably used in the rolling of celluloid films. It might also be advantageously employed in the removal of phonographic disks from the moulds, as well as in the sudden cooling of the disks after impression. I leave those in the business to speak on the subject, not finding for these > conspirators in silence & any other excuse than that they are not alone in concealing the benefits of cold. In consequence of the great increase in the consumption of benzols, the new Industry which has arisen for their recovery seeks by every possible means to reduce the cost of a product so long overlooked. Under the guidance of intelligent engineers understanding the prime importance of that marvellous agent * Colds, coke furnaces producing coal oils are being rapidly erected, utilizing in the manufacture the realization of scientific conceptions, and leaving far behind them the old obsolete and ridiculous plants of our powerful French Petroleum Houses. So true is it that if wealth is the sole happiness of those who possess it, poverty produces among us new ideas profitable to all. * - In the majority of Coke Works cold is utilized more and more to chill rapidly the tar oils used to dissolve the light oils, and for the recovery, in their entirety, of the light essences contained in the gases improperly called permanent, by those who, through inertia or avarice, content them- selves with the easy method of utilizing a cheap but poor yielding plant; in proof of which listen to the report of M. Reidrer, Under the pseudonym of Reidrer, adopted to avoid reprisals on the part of his chief, one of my friends points out, in a report laid before the Congress, the enormous advantage which would accrue from chilling ordinary coal gas before it enters the municipal pipes. He furnishes figures which rendër his report the more interesting in view of the fact that the process indicated by him, after being submitted to a successful practical test, was discarded in favour of other and more complicated processes, It is clear that by utilizing well made temperature regulators, not necessarily absolutely free from leakage, and consequently inexpensive, the prime cost could be easily reduced. 725 Moreover the author intentionally leaves out of account the value of the naphthaline recovered in this manner, which if not of great value, might easily afford a source of revenue which would aid in reducing the cost of the extraction of the gas. - Immediately after and in connexion with gas come the sub-industries occupied in the production of colouring matters. Let us listen to another unknown man. One of my good friends, who, like many others, desires to remain incognito, expresses himself as follows: Cold is used in the industries connected with colouring matters: 1. To lower the temperature of certain reactions and especially the centres in which diazoic reactions take place. These reactions, which produce colouring matters called azoic, take place generally at a temperature varying from 1" to 10°. The temperature varying according to the complexity of the amines treated, falling in general in direct ratio to the simplicity of the amines. E.g. 0° for aniline, 5" to 8° for nitraniline, 20° for Benzidine. 2. In the operation of sulfonation, which plays an important role in the making of aromatics, to allow of the introduction of the organic body into the acid without danger of burning the molecule to the great detriment of the yield. 3. In the operation of nitrification, or in analogous chemical reactions where the maintenance of the mass at a fixed temperature for the whole ‘duration of the reaction is the only condition under which there is some chance of obtaining a given Isomerism, the temperature often having the greatest influence on the place occupied by the nitro group in the body to be nitrified. E. g. Nitrification of acetanilide in which, all other conditions being identical, the derivative para will be formed in inverse ratio to the decrease of the temperature. 4. To separate the Isomerisms, or dissolution of one in the other. E. g. Separation of Ortho and of Para-nitrotoluene. 5. In a number of the most varied chemical reactions such as the oxidation of the leucobases of the triphenylmethanic colouring matters; in the preparation of Indophenols, etc. After hearing such a description it is unnecessary to insist on the importance of cold in this industry and it is still less so when, as we see further, the author estimates that the colouring matter industry has at present in use plants capable of producing approxi- mately 5,000,000 units of cold per hour, and that the world's turnover in the azoical colouring matters alone, has probably an annual value of £ 4,000,000. We, whose sole duty is to consider the use of cold from a general point of view, would simply remark that these processes of nitrification, oxidation, chloridisation etc. are not part of the exclusive domain of the colouring matter industry, and we find in the above information the definite assurance that the makers of refrigerating machinery have a great deal to 726 do, if they will take the trouble to study the Chemical Industry themselves, among those who are perhaps ignorant of the beneficient effects of cold. We have had above occasion to speak briefly of the colouring matter industry. Now cold is not only used during the making of dyes, but it is sometimes, indispensable during the process of dyeing stuffs, and especially silk stuffs, on which the colouring matter must be applied. - The art of dyeing depends on chemistry, and it has profited during the last few years from the enormous progress realized in this science. It has often been possible, thanks to chemical research, to elucidate some of the complicated phenomena arising from the different reactions of dyes on various kinds of textures. s In this way the discovery was made that most of the alterations noticed in dyed textures occurred especially in spring and autumn, when the temperature of the atmosphere is liable to sudden change. In the dyeing of silk, the influence of this temperature is exercised at the moment when the silk is immersed in the bath of tin chloride in solution. Under the influence of a sudden change of temperature, the corrosive, which impreg- nates the fibres when the stuff is removed from the bath, may cause the formation of insoluble precipitate and contribute later on to an alteration in colour of the dyed stuff. After many costly tests, it has been found possible to obviate almost entirely this grave inconvenience by maintaining the dipping, spreading and washing rooms at equal temperatures, and reducing the washing water to the same temperature. - Let us pass from the great and true chemical industry to the problems in regard to the use of cold in the fatty matter industries. Owing to the limited time at my disposal, the very thorough, although very concise, report of M. Bontoux is much too important to be summarized here. This need not however hinder me from drawing the attention of all the members of the Congress to one of the earliest important technical documents published, dealing specially with the use of cold in the numerous fatty product industries. You will find in this work complete reports on the use of cold in the processes connected with Oil, Demargarination, Tallow and Margarine, in factories producing Edible Fats, Vegetable Butters, Soap and Candles. From this enumeration you can at once form an opinion of the importance of cold in the fatty matter industries. Allow me to rectify my sentence immediately and to say: *The importance which cold might havez, for indeed, as I have already pointed out in the case of petroleums, the use of cold is unfortunately not appreciated by makers of fatty products. In spite of acquired facts, many of them stubbornly persist in using barbarous processes, and shut their eyes to the advantages of cold through fear of immobilizing capital and perhaps, in Some cases, of using new machinery, the handling of which frightens them to such an extent that they sacrifice the certain profits which it would enable them to realize. * 727 I should be doing myself too much honour in quoting myself, more- over I have not judged it advisable to devote as much time this year to the most important use of cold in the Petroleum Industry, for the sufficient reason that I said pretty well all there was to be said on this question in 1908, and already at that time I had made ancient history. - It has been necessary this year to select another subject, and, to set an example to those willing to follow me, I have undertaken an extensive criticism of the situation in France, showing not only what has been done, but what yet remains to be done. If I have made myself clear, you will have remarked how numerous and worthy of interest are the applications of cold dealt with. Now I am convinced that what I was able to foresee in the case of petroleum, can be found in all other chemical industries. It is sufficient to wish to see, and to deduct, by a very simple reasoning process, that what is heated must be cooled, and that if it is necessary to cool, it may, in many cases, be advantageous to cool rapidly and well. It is the case in the Candle and all similar industrues . . . . applying the effects of pressure to obtain certain physical separations. Just as I was leaving for Vienna, I was gratified to learn that a Petroleum Refinery in France had put up at its Works a Refrigerating Machine to provide iced water for cooling the worms in which the gases or fumes circulate. As it is customary to cool paraffine oils down to 0°, I asked myself if there were at last a French Refiner who comprehended the use of cold for the refrigeration of the very volatile products formed during the rectification of the essences. I trust that my expectations will be realized and that colleagues, following closely the progress achieved around them, will know how to profit by my indiscretion. - Quite recently I had to obtain from Dr. Edeleanu permission to say a few words to you regarding his process for purifying petroleum, which will soon be generally adopted and will, I hope, lead to considerable modification in refinery practice. By means of his process, Dr. Edeleanu is able to separate very clearly the two principal groups of hydrocarbons, of which the majority of crude petroleums are composed. To achieve his purpose, he utilizes the special properties of liquid sulphuric acid, which dissolves the one group more than the other. By working under certain conditions, which must for the present remain secret, he succeeded in separating from the majority of distilled lamp oils, the oils which are most suited for use in lamps from those which constitue generally the impurities most harmful to the light giving power. Now it just happens that these impurities possess chemically very interesting properties which may make of them a new raw material for the most various industrial products of organic chemistry and especially .* 728 of the chemistry of colouring matters. That is why I mentioned at the X commencement of this statement that the process in question might modify the methods of the petroleum industry. f As for myself, reverting to the principal object of the Congress, I would call members’ attention to the unexpected importance which the dissolvent properties of the liquified gases may have in the future. Dr. Edeleanu has just utilized the dissolvent properties of liquid sulphuric acid in connexion with petroleum oils, and who can affirm that this liquefied gas may not possess the same properties in relation to other liquids And further, why should we not extend our researches to the easily liquefied gases, such as the ammoniac and carbonic acid gases The problem I have just submitted to you has been partly described by Mr. Bontoux in his splendid report on the use of cold in the fatty matter industries, and if I take the liberty of again laying stress on the point, it is because, having been myself in the Stearines before taking up. petroleum, I am able to appreciate the advantages of a well arranged running plant, which would allow of a more perfect cooling of the lumps of acid fat before their first pressure; thus giving a better yield of stearic acid and an oleine containing many less solid products of a higher value. Even to-day the majority of the running arrangements necessitate considerable space and a costly plant, which might be reduced by the use of cold in the running room instead of in the oleine cellar. t This practise is the more blameworthy as in the present instance there is no question of laying down an entirely new refrigerating plant, but simply of removing one which already exists from the cellar, where it is badly placed, to the floor above where it is much more useful. Let us again neglect the alphabetical order and pass to the manu- facture of something which is much used in the industries we have just reviewed. I have little information regarding the use of cold in the special industry producing one of the solvents most suitable for use in the ex- traction of fatty matters. It is regrettable that, like many other manu- facturers, those making or using sulphurated carbon, have refused to furnish information, the utility of which is in direct ratio to the desire to keep it Secret. * - - This reserve is regrettable, but it proves that those who have had the boldness to utilize cold are so satisfied with the results that out of pure selfishness they are attempting to keep all its advantages for themselves. This is a warning to others. - I hope the result of this Congress will above all be to remove this black and depressing veil, and that manufacturers and constructors will feel. one day that the real means of becoming rich is to be found in the common utilization of ideas, and that in this respect, as in many others, if Might is greater than Right at least Union ist strength. ¥. 729 The industrial power of a country may be measured by its consumptio of sulphuric acid. ? Someone who is an anthority on the manufacture of sulphuric acid, but who desires to preserve his incognito for fear of the displeasure of an administration which represses severely all manifestations of intelligenee, writes me as follows: »1. A moderate cold i. e. not below zero is favourable to thc working of the leaden chambers, for the volume of the gaseous masses decreases with the temperature. The same leaden chambers contain more kilograms of sulphuric acid in Winter than in Summer so that it is pos- sible to introduce more sulphur, pyrites and blende into the furnaces. The production of the chambers is also greater in Winter because of the more rapid condensation of the acid formed. 2. A process for enriching the acids to 66°lo (equivalent in practice to 65.5) has been utilized industrially and the crystallization of a definite hydrate was thus obtained, which was separated from the liquid. This process, although extremely interesting, has from an economical point of view not given the results expected . If the industrial power of a country may be deducted from its con- sumption of sulphuric acid, it may also be said that happy peoples consume much sugar. Now . . . . Cold has also been employed in the sugar industry for the extraction of sugar from molasses; but the economical results of the process bave apparently not equalled expectations. Besides, the French Sugar Refiners remain silent on all questions which might injure the good reputation they have acquired for earning their money by a useless process of refinement. -- In my opinion, the most evident use for cold in the sugar industry would be to preserve by cold the raw materials which are liable to rapidly deteriorate, and the treatment of which requires an extensive plant which lies idle for 10 months out of 12 and represents capital badly employed. Unfortunately the raw material (Beetroot) contains 85% of water, and it is difficult to imagine suitable buildings for preserving such considerable quantities as are treated even in the smallest sugar factories. In the opinion of competent persons, the use of cold in the other phases of this industry is not practical, and indeed the separation of water by freezing would cost much more than concentration by vacuum, as at present practised. *- Following the same chain of thought, I was led in the course of my inquiry to suppose that cold might be utilized in the manufacture of citric and tartaric acids, and I had the pleasure of receiving from a very com- petent practitioner the definite confirmation that cold could be usefully employed in his industry. Unfortunately this gentleman, like many others, declines to interest himself in the question as long as he is unable to pro- cure cheap refrigerating machinery. 730 In face of such a reply it was useless to insist, but I might point out to this manufacturer that, in respect of the application of cold to his industry, he would have done much better if he had reasoned like Messrs. Jeancard & Satié, and imitated their endeavour to find out the different manufacturing processes in which cold could be utilized. It can hardly be doubted that as its use spreads and is popularized, cold will become less costly, but it is only in opening to makers of machinery an extensive market that the chemical industries will have a chance of Securing cheap cold. - Among the numerous uses of cold, I may cite also one which consists in cooling in Summer the solutions of bisulphate employed in the treatment of celluloses. Cellulose is at the present time one of the most useful of raw materials. Mention has already been made of its use in the manufacture of gunpowder and celluloid, and I may here add the most curious use of all, namely in the manufacture of artificial silk. Replying to a question on this subject the "Zentrale für Patentsachen der Vereinigten Glanzstoffabriken, Elberfeld & wrote to me as follows: >Sir, With cold it is possible to dissolve in the ammonia a much larger quantity of oxide of copper and to use this solvent in a weaker con- centration. - By the use of cold at 1° the quantity of cellulose dissolved is also richer and it decomposes much less easily on account of the weaker oxi- dising action on the dissolved cellulose of the dissolved oxide of copper.< Questioned on the same subject, my friend Moignot declared that he could not furnish very definite explanations owing to the secrecy observed in this manufacture; however he informed me that refrigerating machinery played an important role in the manufacture of artificial silk. In the manufacture of the silk called * Glanzstoffs, or > Copper silks, cellulose, as is mentioned above, is dissolved in an ammoniacal Solution of oxide of copper and *Schweizer Liquors, and in order that this liquid should dissolve a sufficient quantity, it was recently discovered that the process ought to take place at a low temperature, about + 5°. This dis- covery had the result of diminishing the cost of production of the manu- factured silk and of improving the spinning conditions. The manufacture of > Viscose, silk, says M. Moignot further, is recent and it constitutes a notable progress. In this entirely new industry refri- gerating machines are also used. They are absolutely necessary as a large. number of processes must be carried through at constant temperatures. If we agree with M. Moignot that the world's production of artificial silk will increase steadily from year to year, it is easy to see that the cold industry has here an important future market. 731 This manufacture requires, as it appears, artificial cold; unfortunately owing to lack of time I have only secured very fragmentary information which will nevertheless be useful to those interested in the cold problem. As for myself, they satisfy me and I consider them as a proof of the great extension of the use of cold in the chemical industries. The Chemische Werke Roermonds have been good enough to confirm that cold is utilized in their works to cool the air, which is afterwards ozonized and used in the manufacture of Vaniline. Now everybody knows of the importance of this oxidising agent in the perfumery industry, as well as for the sterilisation of infected waters and the bleaching of organic substances. Certain scientific men, among whom I may cite my friend Henriet of the Observatory of Paris, have attributed properties to this agent which entitle it to be considered as the disinfectant par excellence for the air of large towns, and the sworn enemy of the morbid miasmas transmitted by this element. As we are talking of air, let us pass to the air in Mines. At the beginning of the year I read in the * Revue Générale de Chimie & a very detailed article by M. Lécrivain on the air in Mines, in which the in calculable advantages, from a hygienic point of view, of the cooling of the air in Mines are set forth with considerable competence. In the first place the lowering of the surrounding temperature by the injection of cold air produces a favourable effect on the health of the miners, and on the work done by them. In the second place, as the air which enters cold contains much less humidity than the air which might be simply brought from outside, it carries with it, on leaving the mine, consid- erable quantites of the steam with which it is Saturated, lowering in this way the hygrometrical state of the mine to the great advantage of the miners. * As we desire health, let us rid ourselves as soon as possible of the chemist and his drugs. In a very detailed report on pharmaceutical products, Prof. Tassily reviews the experiments made with a view to utilize cold in the production of essences in which all the properties of the sap of the plant are preserved unaltered. It is true that in spite of all the attempts made, Prof. Tassily is obliged to recognize that practical success has not yet been achieved. Is that a reason for abandoning all reseach in this direction? I do not think so in view of the uncontrovertible fact that the essences obtained in this way in very small quantities are of superior quality — and, in respect of medecine, price must always be a secondary consideration. Moreover, as Prof. Tassily says further on, cold has quite recently been utilized in the clarification of essences, which if left long to settle at an ordinary temperature would very probably ferment or lose their properties. 732 Experiments have also been made to obtain by cold and during con- centration a lowering of the vacuum, facilitating evaporation and drying at a lower temperature. In short, apart from pharmaceutical essences properly called, cold plays a great role in the preservation of certain pharmaceutical products' If human beings can be ill, so it appears can metals. On several occasions I endeavoured without success to obtain from the young Dutch scientist, M. Cohen, a note on the action of cold on metals. As I had the honour of being present at the Conference he gave last year at the Sorbonne, I willingly remind those to whom it may at present be unknown, that, under the action of cold, certain metals, such as tin are, modified in structure and become granular and without cohesion. Further, that when the metal once contains a germ of the new metal, it alters un- ceasingly if it be maintained below a certain temperature, above which it regains its primitive and normal properties. This curious molecular change, as far as it affects tin, was for the first time, studied by Prof. Cohen, who baptised it the "Tin Pest.<. It is apparently common to many other metals and that is why it has been given the more general name of the "Hardening diseases. As an immediate consequence of his discovery, Prof. Cohen recommends that Museums which contain valuable old Pewter should be kept at a minimum temperature of +18%, at which temperature grey, or sick tin is transformed into white, or healthy tin, having no bad or transmissible effect. Doubtless this discovery, still comparatively new, will shortly furnish the key to the curious phenomena of sudden fracture or change in metals. In regard to the utilization of cold in the domain of hygiene and alimentary produce, M. Bonjean, Chief of the Laboratory and Member of the Board of Public Health in France, advocates the cooling of the water obtained from deep borings, which is free from bacilli causing infectious diseases of hydrous origin (Typhoid fever, Cholera, Dysentery etc). He also directs the attention of Municipalities to the advantage of first sterilizing by heat and then cooling the infected surface waters which are always met with in the neighbourhood of large towns. Naturally in stating the problem he does not conceal the great difficulties in the way of execution, owing to the impossibility of separating in a practical manner the drinking water from that used for industrial or even for domestic purposes. As for myself, in the presence of such difficulties I think that the problem will be solved on the day when the diffusion of cold in great towns can be effected by means of pipes, in the same way as water, gas nd compressed air; or perhaps through the general use of small refrige-h rating machines run by electricity or compressed air. * When these machines form part of the normal domestic equipmena tand of the kitchen utensils, the municipalities will be able to supply, throug their pipes, the hot and pure water of subterranean streams, of which a part 733 will be reserved by the householder to be cooled and then used as a fresh, palatable and wholesome drink. Leaving chemistry for physics, the extremely interesting particulars which you will find in the very curious report of my friend Jumau, will enable you to appreciate once more the variety of the problems which offer themselves to an attentive mind in respect of the advantages of an element which is, after all, but the contrary of heat, which we all use, without it ever occurring to us that, since in many cases it is necessary to heat, in many others it is necessary to cool. As regards accumulators, the advantages of cold and heat alternate constantly, and it may be said that it is by exact knowledge of all the phenomena produced during their working that it has been possible to obtain from accumulators the maximum of efficiency. It would be needless repetition to sum up the excellent report which you will have the leisure to study after the Congress, and it will suffice if I refer to those Industries which have not done us the honour of reply- ing to our questions, but concerning which I have been able to procure some interesting notes which I should like to communicate to you. After several failures to obtain information from friends, Mr. Gasnier was good enough to yield to my insistance and communicate to us his interesting views on the future of cold in connexion with the constructien of electrical machinery. All electricians, and those who have occupied themselves with electri- city, have been struck by the overheating of the majority of the pieces and windings of electrical machines: Dynamos, electromotors, converters. This overheating has generally been obviated by the movement of the surrounding air produced by means of fans and only in very rare instances has cold been used. But the cooling effect produced is insufficient, and this is the more regrettable as up to the present the power of most electrical machines has only been restricted by the temperature rise, and that is why my friend Mr. Gasnier remarks that it will be imperative to cool them more and more in order to obtain their maximum efficiency. I may mention that my friend Guittard, Director of the important Thomson-Houston Works in Paris, has asked me to state that he agrees with Mr. Gasnier's conclusions, and I am happy to bring to Vienna the opinion of such an authority. Mr. Guittard, confirming also my general ideas as to the probable extension in a near future of the use of cold, pointed out to me the great advantage to be gained by bringing about in the pumps of the steam condensing machines a perfect refrigeration, which would allow of a much more absolute vacuum and thus considerably reduce the power required by the pumps specially used for condensing the steam issuing from Steam turbines. 734 Among the physical industries using cold I may mention those engaged in the production, on a large Scale, of liquid Sulphuric acid, ammonia, carbonic acid, chloride of methyl, chloride of lime etc. Evidently the object in these cases is to cool below its critical point the gas subjected to liquefaction. It is sometimes unwise to have recourse to great cold, and the idea that cold only begins below zero is a mistake which should be vigorously combatted. In many cases it has not been found necessary to use great cold, and when the object is, for instance, to lower the temperature of a workshop in Summer a few degrees below that of the surrounding air, it should not be forgotten that it is quite possible to obtain this moderate cold by the expansion of compressed air cooled to the temperature of the Surrounding air, instead of by the Úse of refrigerating machines. In its simplicity, the solution of such a common problem should be undertaken on the spot, for under such circumstances the cost of the cold is insignificant. - After having explained to you very briefly the principal needs of the chemical and physical industries, it only remains for me to address an appeal to the constructors of machines. - » It is for you, gentlemen, to produce machines adapted to our multiple requirements; for you to create by your efforts a new market for your industry. But in saying this I shall not have said everything. The task I have undertaken may have led to satisfactory results, but it is not ended, it is only sketched out, and I address myself now to the Members of the Congress to beg of them to continue my enquiry so that at the 3rd International Cold Congress all the physical and chemical industries may be represented. f It is in this hope, Ladies and Gentlemen, that I thank you for having listened to me with an attention which is full of promise for the future. 735 The Rational Use of the Absorption Refrigerating Machine in Chemical Industries. By Dr. Kavan, Civil Engineer, Prague. Mr. Guiselin, in his interesting report, has told us of the importance of artificial cold in chemical manufactures properly so-called, and it is evident that its importance will increase if we can succeed in economically pro- ducing artificial cold. The factories in question are peculiarly circumstanced so far as con- cerns their motive power. They employ non-condensing engines the exhaust steam being used for heating and evaporating. Consequently, the steam engines we find in these factories are never economical, and a condensation of 25 Kg. of steam and even more is nothing extraordinary. If, besides, we consider the rapid change of the processes employed and the limited space, rarely admitting the introduction of new machines, we shall understand the difficulty of producing cold by compression at a cheap rate. It is well known that cold may be produced either by the employment of mechanical or thermal compression. In other words the compression may be effected by mechanical power or by heat expelling the ammonia con- tained in a previously prepared aqueous solution. Machinery with mechanical compression has been so much improved as to make it almost impossible for the absorption machine using live steam to compete with it. It is easy to conceive that the thermo-dynamic cycle of the compression machine proved more attractive to physicists and engineers than the phenomenon of absorption, which is much less interesting from the theoretical point of view. Therefore, we find scarcely any absorption machines in factories with economical motive power at their disposal. -- As stated above, the absorption machine was of no importance so long as it had to be operated with live steam, it could not compete with the compression machine. 736 The expense of energy for producing cold by the absorption process arises from two Sources: 1. Heating the liquid rich in ammoniac due to absorption to a suffi- ciently high temperature to drive off the ammoniac. 2. The separation of the ammoniac gas from the water vapors in the rectifier proper. & Professor Lorenz makes an approximate estimate of a machine of 100,000 frigories. According to him the consumption of heat is 43,000 calories and for rectifying 143,000 calories. - This expense, to which must be added the unavoidable losses, corre- sponds to the consumption of a 30 h. p. steam engine consuming 10 to 11 Kgs, of steam an hour per horse power. We thus have the means of comparison and we see that, with a more economical steam engine, cold by mechanical compression could be pro- duced more economically. But compression becomes more advantageous for the absorption machine if there is unemployed heat in the factory. The thermal power need not be produced by live steam; on the contrary we may obtain it from any source provided the temperature be sufficient. -- If we can effect the heating of the rich liquor by means of unemployed heat, that is to say gratuitously, the actual expense is reduced by about a quarter. And in a number of factories we find enough unemployed heat for effecting the whole process, and consequently the production of the cold will cost nothing at all. The unemployed heat arises from the following sources: 1. Exhaust steam. In many factories the exhaust steam is not used to advantage, and sometimes it is not used at all. It can therefore serve quite well to produce cold. In that case the distillation is done at a temperature rather below 100° centigrade, and consequently is not so perfect as if the distillation were at a temperature above 100° centigrade. The ex- penditure of exhaust steam is therefore rather heavier than in the case of live steam, from 4 to 5 Kgs, of exhaust steam being necessary to produce 1000 frigories. The applications are very numerous, particularly in factories in which it is intended to introduce artificial cold, but where the motive power is insufficient. - Likewise in factories using mechanical compression worked by a steam engine the absorption machine is most practicable if it be desired to in- crease the production of the refrigerating plant. By utilising the exhaust steam of its machine, the factory will obviate the necessity for a new steam engine. 2. Besides, we have the steam emitted from evaporators which may serve for the production of cold, provided the steam be at a pressure of at least one atmosphere. *. 737 I have had an opportunity of studying the cooling of water for a di- stillery manufacturing spirit from molasses. The fermentation taking place at too high a temperature there was a loss of spirit, as it could only be cooled to 20° on leaving the retort. It was impossible to use a refrigerating machine with thermal com- pression; the steam engine was not sufficient and the cost in steam or coal would have been altogether disproportionate to the result. But I found a means of using refuse in the factory which gives off enough steam at a pressure of 0.1 Kilo. The factory is putting up an absorption machine to be driven by this waste steam. * 3. Any factory using high-temperature distillating apparatuses can heat the still of the refrigerating machine with exhaust steam besides economizing in cooling water. 4. The most important source of waste is in the gases of the furnace which are of no further use in the production of steam. I give as an instance the manufacture of nitric acid. The works at Innsbruck which manufacture saltpetre with the nitrogen in the air made experiments with a refrigerating machine with 20,000 calories driven by the hot gases of its furnaces. The results proved so satisfactory that a machine with 100,000 calories was immediately ordered for the same purpose. As you see, gentlemen, the absorption machine, although it has not attained to the perfection of the compression machine, affords us the means of producing cold or ice cheap. All that remains to be done is to perfect the details. Progress has been made in this direction by autogenous welding. The boilers and temperature exchangers which formerly gave trouble on account of the escape of ammonia are now manufactured by means of autogenous welding. Double serpentine tubes, one within the other, of simple and easy construction can now be made to act as coolers and they work in a way which leaves nothing to be desired. I am convinced, gentlemen, that we shall render good service to the chemical industries if we give our attention to the improvement of ab- sorption machines working with waste heat, for by doing so we shall make refrigeration cheap, if not without expense, and from experience I do not know a more efficacious way of propagating a new mode of operation than if it is done without cost or at little expense. 738 Application of Refrigeration to the Glue and Gelatine Industry. By Mr. Paul Cavalier, Mannfacturer of Glue, Givet (Ardennas). Refrigeration has been applied a little to the Glue and Gelatine Industry. - In modern factories it will be very profitable to apply this new method of working, The manufacture of Glue from skins and from all gelatinous substances necessitates working in animal materials which are exceedingly perishable. To succeed in drying these substances (skins and bones), they must be treated, before softening, with alkaline baths of lime or with slightly acid baths. « This treatment lasts one or two months, the length of time taken in preparation depending on the temperature. It is easy to warm up the work- shops in winter to keep them at 10 degrees C. But then excessive heat accelerates the preparation of the material to much, and may set up fermentations or alterations in the material being treated. - This difficulty is remedied by renewing the baths and the washing Water. - If cold water is not to hand, and if the water comes from a river and not from a well, it is expedient to cool the workshops so as to maintain a uniform temperature of 15" degrees Centigrade. This cooling may be ac- complished by drawing in cold air, or more economically by the installation of refrigerating pipes. -- One more important application, often employed, is the cooling of solutions of glue and gelatine in order to accelerate their crystallisation. Solutions of gelatine or glue contain 10 to 35 Prozent of the dry material, this solution is liquid at a temperature above 60 degrees C. It must be placed at this temperature into moulds of a capacity of about 30 litres. Generally the moulds are left one night in the air to cool down, so that on the next day the glue or gelatine has set into a jelly, sufficiently hard to be cut up into slices. Aſ J 37 To have a good consistency of jelly, a temperature of from 5 to 13 degrees C is required. It is moreover very advantageous for the cooling to be rapid. In summer, the cooling is naturally slow and insufficient. - If the night temperature does not fall below 13 degrees C, cooling is slow, and the jelly remains too long at a temperature of about 25 degrees C, and commences to ferment. This last very serious inconvenience is overcome, if the air, on being drawn into the setting room, is cooled down to 5 degrees C, or if a series of refrigerating pipes are distributed about the room. In factories dealing with bone glue, a glue which sets with difficulty, refrigeration is much employed, and has been brought to a high pitch of perfection. - t Refrigerating tables at a temperature of about 3 or 4 degrees C are used. On these tables are placed sheets of zinc or glass, forming a large tray of 10 m. m. depth. The solution of glue or gelatine is poured on these plates, and setting takes place immediately. As soon as a sheet has solidified, it is cut up into squares and put quickly away to dry. Pouring, cutting and drying are thus continuous operations. This last installation is costly in material, but the result is excellent; fermentation is entirely prevented by a continuous and rapid operation, and a dry and uniform cold temperature are obtained. Sk Sk × Air dried by cooling has not yet, to our knowledge, been applied to the drying of gelatines and glues. In Summer, and, above all, in tropical countries, this perfect means of drying organic products will be found useful. Glue and gelatine should be dried at a mean temperature not exceeding 25 degrees C. In order that drying shall take place, the air, after use must be at a temperature below 20 degrees C, and of a hygrometric state below 0.50, permitting an evaporation of at least 1.5 grammes of water per cubic metre of air used. - In summer and autumn when the weather is stormy, the temperature often reaches 17 to 22 degrees C, with a saturation of 0.80. Under these conditions drying perishable organic products such as glue or gelatine is practically impossible. >k - >k >k If the outside air is at a temperature of 20 degrees C, and at a hygro- metric state of 0.80, it contains 136 grammes of water vapour. To bring its hygrometrie state down to 0.50 it would be necessary to heat it to a temperature of from 28 to 30 degrees C, which is too high for good working. ‘740 Air saturated at 5 degrees C would contain 7 grammes of water te vapour. If the vapour is condensed by cooling to this temperature, and the air is heated again to 20 degrees C, it can dry the substance in question by carrying off 2 grammes of water, and would come away at 15 degrees C, containing 9 grammes of water, and having a hygrometric state of 0.75. The problem is thus theoretically solved, but its practical application would be too expensive. ~, $ The manufacture of 1000 Kilogramm of Glue per day requires 1500 cubic metres of air per minute. The apparatus necessary to cool this amount of air would require several kilometres of refrigerating pipe, and would occupy an enormous space. • * $ The principle of drying by air, which has been cooled, dried, and afterwards heated up again, is entirely theoretical, and, up to the present, its practical application is impossible. If the price of liquid air becomes more moderate, the question may, perhaps, be considered again. 74.1 Applications of Refrigeration to the Perfume Industry. By Justin Dupont, Ingénieur E. P. C. in Argenteuil, France. Special applications. Freezing, or refrigeration, of the spirit resulting from the extraction of perfumed oils and fats, as well as from the products extracted from flo- wers by the action of volatile dissolvents. ~ * This operation has the effect of completely precipitating the fatty or waxy matter held in solution or suspension by the alcohol. It has been in use for a long time as well in works making raw materials as in those making perfumery. The necessary lowering in temperature is most often obtained by the use of ice; but apparati have been set up, which act directly, either by cold brine, or by direct evaporation of common volatile substances. Extraction by crystalisation of certain of the constituents of essen- tial oils. -- Anethol: by the refrigeration of extracts of aniseed, star aniseed and fennel. Menthol: by the refrigeration of a Japanese essence of menthol. Safrol: by the refrigeration of the heavy constituents of oil of camphor. Methylnonylcétone: by the refrigeration of essence of rue. General applications. These, which it is not possible to specify, are certainly the most nu- merous. The factory where the manufacture of perfumes is carried out is a chemical laboratory of considerable size. As in the laboratory, it may be said that cold is made use of constantly here. It is employed to moderate reactions, to condense extremely volatile products and to start and regula- rise crystallisation. The following may be cited as necessitating the use of cold, not to speak of well known processes. The extraction of eugenol from the essence of cloves. The preparation of iso-eugenol. The preparation of pseudo-carvine by concentrated acids. The manufacture gaiacol (diagolation of anisidine), and many others. The attainment a high vacuum resulting from a low temperature, ob- tained by means of liquid air, constitutes a new and very interesting method of working in this industry, the larger number of the products of which are so easily changed by the action of heat. 742 The applications of refrigeration to the raw materials of the perfumery industry. By M. M. Paul Jeancard, ingenieur des arts et manufactures Conrad Satie, chief of the research laboratory of the firm: Jeancard, Fils et Cie. The applications of refrigeration to the manufacture of raw materials for perfumery are actually very limited, and consist almost solely in the freezing of «Extracts» for the purpose of ridding these of vegetable wax and animal fat which perfume spirit may contain. Even if these applications are not of great importance it may be useful to examine the various ope- rations in this industry, subject to improvement by the use of refrigeration. It is not our desire to make prophesies in this paper, but only to try to present a series of problems of interest in the manufacture of perfumery. The best way to accomplish this is to review the various operations in the manufacture of raw materials for perfumery. We may class these operations in two main groups: * 1. Manufacture of perfume by means of flowers and plants. 2. Manufacture of organic, synthetical and artificial perfumes. 1. Manufacture of perfumes extracted from flowers and plants. The first problem to solve is the preservation of the vegetable matter before treating it for the extraction of perfume. This industry depends on the seasons. The manufacturer may have to treat two or three kinds of flowers in the same week. The flower seasons are of variable length depending upon atmospheric conditions. One may thus have to treat in a very short time quantities of flowers that usually are treated in periods twice or three times as long. This is the actual way in which the work is carried out. The flowers in reserve are spread out in layers 20 to 40 cm and removed from time to time during the day. * Fermentation is not prevented by this rather complicated means, but simply suspended. Thus roses which had been carefully removed during the day, had lost their colour, and a quantity of their perfume towards 743 midnight. The yield of oil essence was in consequence, much diminished. The problem to solve is, therefore, the preservation of cut flowers, usually without stems, for some days in such a manner as to be able to regularise the working of a factory. The use of refrigeration admits of a practical solution, by means of cold chambers. But this solution is not quite as simple as might appear. in fact, in certain flowers, certain constituents of the perfume are found in the vegetable cells, in complex form, as for instance those of the glucose class. The constituent is set free by the action of an enzyme decomposing the glucose. M. Guignard has, however, recently proved') that cold produces a plasmolysing of the vegetable cells, with the effect of bringing in intimate contact the complex substances and the fermenting reagents. Excessively brisk chilling will therefore burst the vegetable cells, the plasmolyse causing modifications in the perfume of the flower and very probably also in the quantity of essential oil. * Refrigerating chambers are certainly of use in the treatment of the Jasmin and the Tube rose, flowers largely used for perfumery. This work is accomplished from the end of July to the end of Oc- tober, that is, in the warmest season of the year. The perfume from these flowers is extracted by senfleurage», a process consisting in stretching out the flowers each day on glass frames, coverca by a thin layer of grease; a treatment which requires considerable skill. The layer of grease must rest undisturbed during the manipulation in such a manner that the pressed flowers can easily be withdrawn without loss of perfume oil. - In factories of any size these manipulations are performed by hundreds of workmen who spend all day in the rooms. It is therefore obvious that the refrigerated rooms should admit of this work being done in a con- venient and hygienic manner. The same refrigerated chambers could be equally well used for the treatment of perfumed pomades. 4. In the preparation of extracts, cold at about two degrees below zero C is is employed for eliminating vegetable wax and animal fat. The im- provements applicable to these processes consist only of details, depending principally on the individual work of each factory. In the process of extracting perfumes by distillation with steam, the use of cold, can be conceived for increasing preserving power. This matter would have a great importance if the use of distillation under reduced pressure was recognised. II. Manufacture of organic, synthetical and artificial perfumes. Since vaseline has been synthesized and since the discovery of artificial iomore and musc, the manufacture of organic, synthetical and artificial per- 1) Guignard: Comtes rendus de l'Academie des Sciences de Paris 1909, 744 fumes has obtained a very great importance in the industry of raw materials for perfumes. t * * This manufacture depends on the industry of organic products, and all the possible applications of cold cannot be revieved here. It is used for instance to extract certain essences from constituents which are important commercially such as anethol, menthol, etc. It plays an equally indispen- Sable part in purification by crystallisation. Certain condensations and ex- tracts do not give commercial products except under conditions where a relatively low temperature is employed. 745 Use of Cold in the Pharmaceutic Products Industry. By E. Tassilly, Doctor of Sience, Prof. Agrégé à l'école de Pharmacie, Paris. The first attempt in the employment of cold in pharmacy is due to J. Ch. Georges, Chemist to the Court of Stockholm, who published in 1799 in the Journal of the Society of Pharmacists in Paris a monograph on the subject of the way to concentrate lemon juice without risk of its decompo- sition. A little later Mirabelli’) in his Lessons in Pharmaceutical Chemistry, recommended freezing in the process of concentration of vegetable acids, vinegar, lemon juice and all acidic solutions. Towards 1830 the German Pharmacist Busch”) proposed freezing the extracts while uniformly agitating the mass so as to form little crystals of ice which are allowed to form until thy become almost colourless and taste- less. Evaporation is then finished in the ordinary manner. Extracts thus prepared, possess to all appearances, in a high degree, the taste and smell of the fresh plant. A gain, Pfeiffe rº), pharmacist, St. Petersburg tried freezing the mass in order to succeed in concentrating medicinal solutions. - In 1877 Professor Alphonse Her rer a*) observed that it was possible to remove by freezing, the larger part of the water from the aqueous solu- tions intended for the preparation of pharmaceutical extracts. Heat only came in to finish the concentration, and the substances susceptible to alteration by heat remained unaltered. Adrian, in an interesting work") from which we have borrowed the above historical data, has stated that in the case of the Herrera method: , ) Bulletin de Pharmacie 1324 (1809). *) Archiv des Apothekervereins XXXIII, 59 (1830). *) Archiv der Pharmacie LI, 28 (1847). º 4) American Journal of Pharmacy 437 (1877) and Journal de Pharmacie et de Chemie 4th S. XXVII, 149 (1878). 5) Adrian, Historical Study of pharmaceutical extracts. Vol. 1 in 8°, Edit. Paris (1899). 746 1. The total quantity of water removed by freezing three times does not exceed 60°/o, and much still remains to be evaporated. . 2. The ice separated out contains in its interstices quantities of the medicinal liquid unfrozen, varying from 10 to 20% according to the size of the crystals, and in spite of the use of a powerful press. Moreover the dessication with free air or air in a stove at 30° C has its disadvantages. It has then been necessary in the Courbevoie factory to remedy these various inconveniences, by Secouring more favourable conditions for freezing the liquid and for separating out the ice; so evaporation was completed at a low temperature in vacuo, by means of the apparatus decribed on page 147 of the work mentioned above. For the production of cold an ammonia machine of the Mignon et Rouart type is used, easily giving a temperature of 20°C, and allowing 200 Kilogrammes of liquid to be worked upon at a time." The vegetable solution prepared by the usual method, and filtered in a filter press, is turned into ice moulds, and allowed to remain there until the temperature of the solidified block reached 10° C. Then the blocks, being removed after a short immersion of the moulds in warm water, are trans- formed into snow by a special crushing machine, and then submitted to eva- poration in portions of 25 Kilogrammes. 75°/s of the water is thus separated out, and the liquid extract obtained is submitted to freezing a second time at a lower temperature, 12°C for instance, then to crushing and evaporation, as in the first operation. From 100. Kilogrammes of liquid are obtained 12 to 15 Kilogrammes of a syrupy extract which may easily be brought to the usual consistency in the vacuum apparatus mentioned, at a temperature not exceeding 30° C. In spite of all the interest attaching to these attempts, it must be re- membered that this method has not come into practice. The objections which may be made to the process bear upon the follo- wing points: Cold only allows of the somewhat slight concentration of dilute liquids. When the liquid is however slightly concentrated, the crystals of ice retain much of the extracted matter, and the yielding of the extract is affected thereby. It is necessary then to finish the operation by employing heat. Con- centration by cold can only, in consequence, be employed when the liquide are dilute, and hence very little affected by heat, even in the worst con- structed vacuum apparatus. - Moreover concentration by cold would involve more work than con- K centration by heat, - 747 There may be opportunities of renewing the attempt with the means which are now available. But there is another problem which may be solved in a effective manner by the use of cold. I speak of the purification of the extracts, and here again it is Adrian to whom we are indebted for the experiments carried out in this direction. It is well known that partially concentrated extracts, left in a cool place, deposit, at the end of certain time, an insoluble precipitate which may be eliminated by pouring off, or by removing the extract with a small quantity of cold water. But, if the extract yielded in the required condition, is kept at a tem- perature in the neighbourhood of its freezing point, one day is a sufficient time in which to obtain the precipitation of the insoluble substances. In the Courbevoie Factory, use is made, for this purpose, of a small chamber which can hold 200 Kilogrammes of the liquid, and crossed by an iron tube through which circulate a cold solution of chloride of calcium. If the cooling liquid is at — 20° C, the temperature of the air in the chamber descends at the end of an average time of four hours to + 1 or + 2° C. Toward the end of the day pouring off or filtration can be formed, these operations being effected by means of syphons from the interior of the chamber, which only remains open long enough for setting up the ne- cessary arrangements. By working under these conditions, the fermentation of the liquid, which might take place where pouring off took place slowly at the ordinary temperature, is avoided. Unfortunately, as in the former case, a very serious inconvenience crops up; this is that liquids thus cooled, loose a portion of their extractive matter, and the final yield is very bad. This loss in extract by cooling shews itself also in the case of liquid extracts of equal weights of plants. The liquid originally at +18% C, often becomes turbid at 4°C, and does not always come back to its original con- dition at + 15° C (Boulanger-Dausse). * The result of this is, that the use of cold in the preparation of ex- tracts, whether it be in their concentration by freezing or in their preser- vation during purification, has not up to the present given results justifying its general application. Nevertheless, cold may come in, in the concentration of extracts, much more indirectly it is true, but in a really effective manner, as we shall see: The extracts are obtained by evaporation by heat in an apparatus exhausted of air, but in these apparati, the limit of the vacuum possible is determined during working by the vapour pressure of the condensed liquid. For water vapour the figures are as follows. 748 At 25° C the pressure is 20 mm of mercury. » 200 C ~ } * 17 x > 3) . * 100 C ~ X) x 10 * * X) x 50 C ~ X) * 7 x > X) X) 00 C ~ Y) » 5 ° X) y In consequence, the lower the temperature of the condensed liquid, the higher the degree of vacuum reached, and hence evaporation and desic- cation may take place at a lower temperature. It would be ideal to eliminate, or almost eliminate, the vapour pres- sure of the condensed water; this may be accomplished by the absorption of this vapour by concentrated sulphuric acid, and Messrs. Boulanger-Dausse have succeeded in obtaining a vacuum of 1 millimetre in an apparatus having a capacity of 250 litres. The use of sulphuric acid has its inconveniences. Messrs. Boulanger- Dausse have constructed a double refrigerator; on one side the vapour is condensed in an apparatus, cooled at the surface by means of well water at 13 or 14°C, because it is the transformation to the liquid state from the vapourous state at the same temperature, which gives out the largest number of calories. The condensed water falls upon a cylinder in which circulates cold brine, and between the cylinder and the vacuum pump is a second brine refrigerator coil which would condense any traces of vapour which escaped the first cooler. Under these conditions, Messrs. Boulanger-Dausse estimate that the condensed liquid is sufficiently cooled to make full use of the full vacuum produced by the pump. Again, besides in the manufacture of pharmaceutical extracts, menti- oned above, sold may play a part in the manufacture of Opo-therapeutic preparations, particularly where the preservation of the raw material is concerned. Thus Messrs. Frimouze & Co. have provided themselves with a little refrigerating chamber, which is cooled by the compression and expansion of carbonic acid gas, for preserving the beef which is to undergo treatment on the same day. > * A refrigerating room of considerable size is now being constructed at their factory. - The Byla jeune Establishments of Gentilby use ice houses for the immediate preservation of meat, and the materials for opo-therapeutic products. A. - The liquid ferments are also preserved in ice houses up to the time of their sale. In the factory of Messrs. Darrasse-Frères at Vincennes in the prepara- tion of extracts, and in the drying of the various organic physiological pro- ducts in vacuo, the water vapour is condensed in an ice refrigerator, which '749 , allows of quicker drying or of distilling at a lower temperature, without making use of sulphuric acid as a dehydrating agent. Such are the conditions under which cold may take part in the manu- facture of pharmaceutical products. This part, none the less interesting because its scope is limited, and already in the present state of things it can be predicted that a remarkable extension of this method of working will take place shortly. 750 The Application of Artificial Cold to the Rubber Industry. By J. Boutaric, E. P. C. Consulting Engineer of Paris. We have a twofold object in undertaking this report. Its principle object is to examine the advantages which the rubber industry may derive from a somewhat general application of artificial cold. Moreover it includes an account of the considerations, and, as far as possible, of more precise information which govern the form etc., of the new physical agent which it is proposed to use. But it is obvious that these two points of view cannot be considered. separably. It is only necessary to endeavour to treat each of the problems under- taken in such a way as to supply the greatest possible amount of infor- mation to rubber merchants and manufacturers on the one hand, and to. machinery manufacturers on the other. Moreover, as the use of cold has hitherto been very limited in the industry with which we are concerned, we need not seek in this report to describe present methods of manufacture, but only to give an essay on the possibilities of certain operations. The information which has been acquired up to this time on the properties of this material will serve as a basis and justification for the new ideas which are to be described. To make our paper clear, and for convenience, we shall divide it into. two chapters, the first dealing with all which concerns the production and trade of the raw material, and the second with questions concerning the manufacture of vulcanized rubber. -- We are obliged to begin each of these divisions by a brief description. of the present state of the industry in order to throw light on the factors. which govern it, and to effectively cope with the problems involved in the application of cold. CHAPTER I. The Production and Trade of Raw Rubber. Let us pass in review the various sources of the raw material. The principal plants yielding rubber in their sap can be classed in the three following families. 751 The Euphorbiaces, Artocarpes, and the Apocynaces. We shall see further on that for completeness we should cite two more families, the Asclepiades and the composites among which some plants are found which practically yield rubber. There are, besides, trees, vines, and some kinds of bushes which yield the raw material. Among the Euphorbiaces are fme Hevea, of which the most important, the Hevea Brasiliensis, is exploited over the whole of the Amazon basin. It gives the greatest proportion of the rubber used in the world, and at the same time the quality most appreciated. If the production of the world is estimated at 70,000 tons per annum, the well-known variety known as "Paras constitutes a large proportion of the 37,000 tons of rubber produced by Brazil during the year 1909. The refuse of this production is known as "Sernamby Manaoss. Now these are the same trees which it has been proposed, very prac- tically, to acclimatize at Ceylon and at Malay. The success of these attempts may now be announced, seeing that 1000 tons of plantation Para rubber were sold on the European market during 1907, and nearly 1600 tons in 1908, and that the statistics, counting on a still greater advance, predict equal qualities of the two varieties original Paras and >plantation Para º ten years hence. The Manihot Glaziovii should be included in the same family; this variety, growing in the dry and barren district of Ceara, yields the variety known as Manicoba, also another tree, the *Sapiums, which is very plentiful in Ecuador and in Columbia, whose sap is often mixed with that of the Hevea. In the Artocarpes family are classed the xCastilla Elasticas, which is found in tropical North America, in Peru and Columbia, and which, accor- ding to the method of coagulation adopted, and very probably, according to its mixture with other saps, provides the following varieties: •Mexicans, >Peru-Sernambys, x Cauchos etc. In this same family are also classed the "Fiacus Elastica & which is found in Indo-China, in Borneo and in the Dutch East Indies: These are the large trees and roots which furnish a variety of rubber whose qualities are very different from those of the varieties which we have just mentioned. Nevertheless, attempts have been made to cultivate them in the Malay Archipelago alongside of the Hevea, because they are already acclimatized there; and there is no reason why the rubber furnished should not be improved by culture first, and then by the method of coagulation. We find both trees and vines in the Apocynaces family. Among the trees are the "Hancornia Speciosas which yields the variety known as * Mangabeiras, in the province of Bahia; then, the x Funtumia elasticas which is found in Africa on the Gold Coast, in Cameroun, and whose sap enters into the composition of a large number of Congo rubbers; we should also mention the x Mascarenhasia & which is found on the east coast of the island of Madagascat. * 752 But the Apocynaces family yields its best contribution to the rubber production by the very abundant and remarkable vines which are the wealth of the Congo district. These are: The * Laudolphiasº, African varieties of which, *Laudolphias Ovariensis, and especially the Gohines vine, pro- duce the most appreciated varieties in the Soudan. ++. Similar vines grow in East Africa and Madagascar, and everyone knows. what good rubber we get from Mozambique. & It should be added that Madagascar has reserves of many and good varieties, which it would be advantageous to cultivate, because besides. representatives of the above families there is the "Marsdenia, belonging to the "Asclepiades's family. We should say a word about the plant *Portherium Argentatum, which is found in large quantities in Mexico, and from which a useful rubber is extracted by special patented processes, but whose practical value cannot be compared to that of Para rubber or even to that of the other so-called secondary varieties. - *. When we consider the different sources which provide the sap and gum for the industry, we come to the certain conclusion that, in spite of the difficulties inherent in the exploitation of virgin forests and plantations, there is no lack of raw material for this industry. *- A surplus production which would lower the price considerably cannot be expected for several years to come, because the industry could easily absorb a much larger amount. A good state of equilibrium may then be counted upon, and we may with perfect safety devote our energies to future improvements. But, up to the present, the outstanding characteristic of the production of rubber is the great irregularity of the product as can be seen from several figures, compared together, most of which are the averages for a - large number of tests. Let A = the elongation at rupture of a bar 100 mm. Let R = the resistance per square millimetre at the time of rupture. C = * a coefficient to which we do not attribute any physical signification, but which has the advantages of including these two values: * ... - * A. B C Brazil Para . . . . . . . . . . . 842 1354 575 Plantation Para . . . . . . . . . 840 1°339 562 Sernamby Menaos . . . . . . . . 820 1:200 492 Manicoba . . . . . . . . . . . 820 •920 377 Sernamby Peru . . . . . . . . . 930 ‘750 345 Gaucho . . . . . . . . . . . . 910 •72O 327 Niggers . . . . . . . . . . . . 1040 •700 364 Twist . . . . . . . . . . . . . 960 670 320 Indo-China . . . . . . . . . . . 1010 '490 245 753 We will now consider the sap and give a description of that of a Hevea plant, according to Mr. Victor Henry (in his various publications and especially the review • Le Caoutchouc et la Gutta Perchas, May 1906 and May 1907). x- r This sap has a slightly alkaline reaction, its density is 973, and it gives 87 grammes of rubber per 100 cubic centimetres, which is a poor yield. The electric conductivity of this sap at 25°C. is 3,300X106 equal to that of a solution of 25 grammes sodium chloride per 100 cubic centimetres of water. The globules of rubber in suspension in the liquid are not all of the same size, half of them are large and of a diameter of 2 p., the other half are smaller and of a diameter of ‘lº p. - Their >Brownians movements are more intense as they are smaller. We shall now see how coagulation transforms the moving globules into crude rubber. Mr. Victor Henry gives the best explanation. When different substances are added to the sap which we have just described, although no change is observed, and precipitation is obtained in the form of isolated flakes, agglutination takes place, which gives by compression a fair raw rubber; although it forms itself into a compact clot, it is real coagulation which provides raw rubber of commercial value. Thus the final result can be varied at will so to speak, and nothing is more instructive from this point of view than the following table, given by the author whom we have just mentioned. With the same sap the following results have been obtained. A. B Coagulation by heat and evaporation at 80°C. 610 170 By simple evaporation on the stove at 25°C. 500 • 190 By concentrated acetic acid . . . . . . . 710 “210 By trichloracetic acid, washed and dried for 96 hours on a stove . . . . . . 600 '325 Coagulation A § . º} * 530 *310 Coagulation B (more dilute acid and two electrolytes) . . . . . . . . . . . 560 '490 Coagulation by C (1 of acid 2 of salt) . . 620 '660 It can easily be understood how it is that the trade has to deal with such variable products, by reading this very incomplete list of the methods of coagulation employed. At Ceylon by chemical products such as acetic acid. At Guayule by mechanical treatment of the plants and by washing with water. By centrifugal separation of the sap, a method in use on several plantations. N 48 754. By heat, and especially by hot gases or steam as is done for Brazil Para. By boiling the sap or by letting it evaporate in the sun on porous soil etc. In the above we have mentioned several matters which we shall make use of Let us imagine the substance (C, Hs) held in suspension in the Sap in the form of globules of various compositions but always in the proportion of 5 of carbon to 8 of hydrogen, varying in a similar way to turpentines from various sources. These globules are in equilibrium in the serum, which undergoes the same influences as the rest of the vegetation. w Coagulation is the result of destroying this equilibrium by various means, so that it sets up molecular combinations more or less stable. --- We do not need to emphasize the importance of the physical state of the substance after coagulation. The essential point, after what we have just said, is to seek a means. of enabling producers and planters to remedy the irregularities which we have mentioned, and which are perhaps more noticeable in recent productions than in the older ones. In fact, in the preceding table we found that the characteristics of Brazil Para and Plantation Para are fairly alike, but as each of these figures is the result of about 20 tests we shall take the minimum and maximum values in each case, and thus we have: C. Max. Min. Difference Para Brazil . . . . . . . . . . . 670 441 229 Para-Plantation . . . . . . . . . . 710 392 318 From this we see that it would be very advantageous to make some attempt to render the productions of Brazil and Plantation Para more uniform. Up to the present the methods in use are based upon the treatment of small amounts of sap at a time. It is coagulated as fast as it is produced without waiting, and is hurried somewhat by the phenomenon itself. Now what is sought is to make this operation more economical. This means collecting and storing the sap so as to mix it and treat it in fairly large quantities. Its carriage and preservation constitute the great difficulties in this case. Nevertheless it is known that certain chemicals such as ammonia and formaldehyde retard coagulation and so allow of its being carried about; certain sanguine people even suggest treating it in European factories. But let us keep within the domain of the plantation, and endeavour to store the sap for a certain number of days in artificially cooled receptacles; we may expect to be able to preserve this liquid in the same way as other organic liquids are preserved, without adding any other substance, so that it retains all its original properties good and bad: by simply increasing their stability, which can be effected by lowering the temperature. Thus the manner and time of effecting coagulation can be chosen; without doubt intense cold 755 would not be necessary in this case, and several degrees above zerc, Say + 10° C., would prove a suitable temperature. It is hardly necessary to add that several tests would be necessary. If we assume that 1,000 trees, spread over an area of 4 hectares would produce 15X20 litres of sap, per day, and about 350 kilogrammes of rubber per 1000 litres of sap, we can easily calculate the quantities of liquid which would have to be cooled. After mixing the sap, it would be put away to coagulate, and this operation could be effected as slowly as desired by Suitably warming it up, which would be advantageous as far as can be seen. It is necessary to dry, store and then to pack the rubber which has just been coagulated. Now these operations are not without importance, as we shall see, and they give rise to several observations. It is, in fact during these manipulations and only several weeks after coagulation, that the commercial value of the rubber obtained can be ascertained; we know, to use the common technical terms (for want of better), that one specimen of rubber may be > nervouss, 2 elastick, ”Sounds and » dry -, and hence fetches a high price, while another specimen is "soft.*, »plastics, 2 turned thicks or > moists and hence depreciated in value, so that it fetches a low price. Now it is quite obvious that it is too late at this period of its manu- facture to remedy most of the faults ennumerated. We know that they are the result of the two factors previously analysed, namely, the variety of plant on the one hand, and the method of coagulation on the other. But it must be added that the physical and chemical conditions under which the raw rubber is placed have an irresistable effect in either accele- rating or retarding the appearance of these defects. Let us particularly examine the case of >turning thicks or 3 stickings which is the best known defect because it is the most easily observed. The material becomes viscous and sticky in places and the defect spreads from place to place; see the opinion of M. Bertrand upon this phenomenon (>Caoutchouc et Guttaperchas, page 3916). >Turning thicks is not due to fermentation that is to say to any decomposition set up by micro-organisms, but to an irreversible molecular change due to a combination of physical and chemical conditions, among which heat is particularly influential. Moreover, the same writer shows that certain botanical varieties generally produce pitchy rubber, and others give rubber which rarely has this defect. Lastly, we would add that certain hydrocarbons, such as (C, Hs)h, present in the sap and globules, have possibly not fully matured, so that, caught among the others on coagulation, they are ultimately affected by conditions under which they are placed, such as heat, and may even dissolve the mature hydrocarbons surrounding them. 48% 756 Let us sum up the above information, and assume the substance obtained iby coagulation to be a more or less complete and stable molecular compound which will break up in time, which generally means deterioration, and at a rate governed by a law which essentially depends upon the physical and chemical conditions under which this substance is placed. We will then understand how it is that so many varieties are obtained, some elastic, some plastic, and some which are affected with less serious defects than ºstickings, but wich exist nevertheless. e And we arrive at the conclusion that: } Among the agents which we have at our disposal to counteract internal changes, cold should be one of the first to be tried. Especially should drying after coagulation be carried out at a temperature below 25" C., this temperature being lowered as the water disappears, also the rubber should be stored at a temperature between 15 and 18° C. We find an article written 1904 by M. Van Den Kerchove (Caoutchouc et Guttapercha, page 151) on a store for preserving rubber in the tropics. We give the following extract: R To store 150 Kilogrammes of raw rubber in a storehouse having a capacity of 200 cubic metres, the average temperature being 26°C. in the shade and 35°C. in the sun; to maintain the temperature of the storehouse, constructed of insulating materials, at 15° C. necessitates the removal of 4000 calories per day, plus about 700 calories due to renewing the air once every 24 hours. We shall see in the second chapter how we may follow, and if necessary, justify all the propositions which are made here, but before finishing we should like to consider the action of more energetic cold (40° or even more) upon dry raw rubber. | - The instance of such a unique trade as the English sheet rubber industry is quite sufficient argument for making decisive tests on this matter. For, after grinding the gums used in this industry, they are submitted to a very heavy hydraulic pressure and kept at a low temperature for a month. The period at which they should undergo the operation may easily be computed, and it can be predicted, that the warehouses at the port of arrival would obtain an extensive sale if they gave some attention to rational storage, with the application of artificial cold to all raw rubber. CHAPTER II. The Rubber Industry and Trade. After having given an account of some attempts which might be made to provide factories with an improved product by making use of artificial cold as we have just shown, we will consider two very important questions. 1. How shall we make certain that the improvements effected on the raw rubber are retained, and make themselves felt in the manufacture of vulcanized rubber? 757 2. Also how can the same physical agent namely cold, enter again into the manufacture or trade of vulcanized rubber? s First let us describe very briefly, because it ought to be already known, what operations are carried out upon the raw material in a factory. We know that cutting up is made necessary by the impurities present in the gum, and that the slices of material are washed in cylinders. Drying is the inevitable sequel of this operation. It is most often effected in free air and at the ordinary temperature, but if it is desired for numerous reasons to accelerate this drying, it becomes necessary to ventilate with warm air so as to increase the weight of vapour absorbed by air. But it can be seen from what has gone before, that this warming up has its disadvantages because of its certain action upon the gum. If then there is an economical means of obtaining dry air at the ordinary temperature or even at a lower temperature, it should certainly be applied to the drying of cut up gum. The gum is then ground in cylinders warmed up by steam, so as to make it soft to mix it with the necessary ingredients and chemicals, such for instance as Sulphur. Other machines, such as rolling machines, cutting machines, and moulds, make the mixture into sheets of regular thickness or shapes according to design. If we investigate the influences of all the above operations on the material, we see that there is a physical modification after each treatment. To make certain of this it is sufficient to make a solution of the same sample after each treatment, and to determine the viscosity of these solutions also to examine them under a microscope. Here are some figures which show the changes which take place: a specimen of plantation Para, not cut up, gives a solution of 2% of gum in benzine, which has a viscosity of 2,200. The same gum, being ground for variable periods gives solutions where wiscosity decreases as is shown in the following table: Time of Grinding, Viscosity of a 29/o solution. 2 min. 5 sec. 1.900 Sec. 5 * 540 x 10 × 150 x 15 x 110 × 2O > -- 90 × 30 X. 70 X 40 s 65 x 50 s 60 x 60 X. 59 X The numbers representing the viscosity are in seconds, because, either the time is measured wich it takes for a certain volume of solution to flow 758 through a cylindrical tube, or the time it takes for a glass rod to traverse the same column of different solutions, and this number must be determined after the gum has remained in the solvent for a fixed time. If grinding of the sample is stopped after 10 min., the viscosity of the 2°/o solution being 150 seconds, the viscosity may be made to fall to 100 seconds by passing the sample through a rolling machine. This is sufficient to determine the changes which we mentioned. We notice also that the tendency of the change is always the same, and it seems that the material is simplified in its molecular composition. It would, as far as we can see, be of advantage to arrest this simpli- fication as quickly as possible, and this explains the fact that other advan- tages may be expected from a rational treatment of the crude gum; this is the abolition of cutting up and drying of plantation gum at the factory. This is an economical advantage from the point of view of motive power, labour, and encumbrances, and has also the advantage of diminishing the capital invested, and the practical benefits of doing away with a mechanical operation the inconvenience of which we have seen. The above enables us once more to indicate in a general way the method by which the advantages are derived, which may be expected from the various applications of cold which have been mentioned here especially in the first chapter. - In fact it can be seen how it is that the viscosity tests which can be made on solutions, or the ground up gum itself, give certain indications of the states through wich the elastic molecule itself passes; but this sensitive test does not give any conclusive evidence as to whether the said changes are advantageous or not. It is therefore necessary to devise supplementary tests on the mechanical properties of the gum in each of the states which we are considering. However this may be, we are now come to that stage in the process when vulcanization takes place. We know from the above that the moulded or shaped sheets are used to make various articles. The material of which these sheets consist has arrived at a state of simple molecular composition which may be very variable from time to time, if care has not been taken to carry out the various processes quite perfectly. Now vulcanization has the certain effect of fixing the shape of object, while giving the material some very remarkable properties, which entirely depend upon the state of the material immediately before vulcanization. Here are some interesting figures dealing with this subject: an American gum, ground for 30 minutes and vulcanized in the form of a sheet 1 mm. in thickness, gives the following characteristics: A = 820 mm. R = 1.4 kg. C = 574, 759. ***. The same gum, ground for one hour and vulcanized under the same conditions gives: - A = 810 mm. R = 1.1 kg. C = 445. Another sample of African gum, ground for 20 minutes and vulcanized in the same way as the above, gives: - A = 1020 mm. R = 7 kg C = 357. The same gum, ground for 40 minutes, gives: = 925 mm. R = 410 kg. C = 189. These numbers give the differences observed, and they show, whatever the source of the samples, that the phenomenon is very general, and that it is more active on second rate gums than on the best gums. So it is quite reasonable to ask if the influence of cold on the crude gum might not serve to correct these seemingly inevitable irregularities. This physical agent could produce, on the spot and quickly, the same effect as is produced by a prolonged rest which in some cases is made use of to good effect. - - We are not concerned here with vulcanization, and will proceed to consider the material which it produces. - - Contrary to current opinion, vulcanized rubber is still very sensible to the physical and chemical conditions under which it is placed, heat especially causes it to deteriorate rapidly. M. Bonasse has shown us this by numerous ‘experiments. It would be absurd to say that vulcanization makes rubber unaffected by variations in temperature between 10° and 80° C. for instance, and that it is indifferent so to speak, to mechanical action, because it resumes its original form after deformation. For in reality it is quite different, and to get an accurate idea of this matter M. Bonasses experiments should be studied, dealing with vulcanized rubber and published in the "Proceedings of the Faculty of Science at the University of Toulouse for 1903 and 1904s. - We see at once that two phenomena in the deformation of vulcanized rubber should be observed, one immediate and one retarded. The difference between the two is best described as being an accentuated form of hysteresis in the material. Moreover it has been observed that every mechanical operation on vulcanized rubber results in an internal change, stable for the most part, without a definite limit, and which particularly influences the hysteresis. It is the same when it is subjected to a physical action such as heat: the immediate deformations always increase with the temperature, if the time does not exceed a few hours; at a temperature of 60° C., for instance, the phenomenon is easily observed. As to the retarded deformations these are diminished at the temperature at which vulcanisation takes place and increased at lower temperatures. But these effects due to temperature are not permanent. 760 We find one of the same set of experiments dealing with the effect of cooling down in carbon dioxide snow; the deformation observed did not cause breaking, whence the writer concluded that the effect of cooling is nil. 3. Here it should be recalled that Mr. Claude has shown that vulcanized rubber placed in liquid air becomes hard and brittle like glass. Its proper- ties are very much changed under these conditions but very little trace of the changes remain when it regains the ordinary temperature. As a matter of fact it is well known that the greatest difficulty en- countered in the treatment of rubber which has been used and which is to be used again, is the powdering of the material. ^: Powerful mechanical means are needed to solve this question, and this method has its disadvantages as we have seen. - It is to be hoped that the liquid air industry will take up this matter, the crushing of waste pieces of rubber at a low temperature. Lastly, if there does not seem to be much reason for attempts to be made to apply cold to the manufactured goods after vulcanisation, never- theless something should be said about the storage of vulcanised rubber, and we should examine if everything is as it should be in the industry, particularly from this point of view. If an analysis be made of the properties of a sample of rubber immedia- tely after vulcanisation, and afterwards at regular intervals, it is once more observed that the properties of this material are not stable, and that a slow change takes place which greatly depreciates the commercial value of the goods because they will not perform the duties for which they are in- tended. Here is a test which we have recently made on two samples of African Gum apparently of the same origin botanically, but so differently treated coagulation that one is clean and white, whereas the other is black and pitchy. The two gums, treated in the same way and vulcanised with 10% of sulphur in the form of an inner tube for a bicycle, had the characteristics shown in the table. Black Gum. - A mm R kg C 5 days after vulcanisation . . . . . 880 ‘920 405 6 at 459 C. . . . . . . . . . . 870 1*020 443 12 > * > . . . . . . . . . . . . 780 ‘800 312 18 x * > . . . . . . . . . . . 720 '640 (230 24 x * > . . . . . . . . . . . . 760 '700 266 30 ) > x . . . . . . . . . . . 762 ‘72O 274. 36 x > * - 660 '480 158 6 months of storage between 15 and 20°C. 630 ‘700 238 761 White Gum 5 days after vulcanisation . . . . 930 '650 302 6 » at 45° C. . . . . . . . . 1000 ‘920 460 12 > x > x . . . . . . . . 960 •980 470 18 x > * > . . . . . . . . 920 ‘760 348 24 » 2 * > . . . . . . . . 820 '690 232 30 x > * > . . . . . . . . 830 ‘710 294 36 x > * > . . . . . . . . 820 ‘500 205 6 months storage between 15 and 20° C. 950 ‘810 384 It can be seen from this, that during storage the qualities of vulcanised rubber pass through a maximum and then depreciate more or less rapidly. We should add here without entering into the details of such a matter, that we have chosen the most complete example, but in the case of many of the qualities the depreciation commences almost immediately after vulcanization. A necessary condition in finding the maximum is to find the point of vulcanization, but this condition is not always sufficient. However this may be, we may say that we know that there is a considerable waste of gum, simply caused by their being warmed up to a moderate temperature. When the time is prolonged to several days, exposure to a tempera- ture of 45° C., and over, modifies vulcanized rubber, and this modification is not the same as that of which we have spoken, given by Mr. Bonasse. This investigator has also mentioned the second change. We have no detailed knowledge of the mechanism, but this is not necessary for the end we have in view, and it is enough to state that rubber goods are often stored at a temperature resembling that of a stove. The storehouses frequently attain a temperature of 30 to 35° C. in summer, which causes the deterioration. - It is therefore quite a practical proposition that storehouses should be made suitable for these goods. An average constant temperature of 18°C. should be obtained, also light should be excluded and the air renewed without a current; a low hydrometric state if cloths are used, and a high hydrometric state if only rubber is present should be secured. We should thus succeed in eliminating the changes mentioned above, and keep the goods in the factory for one or more seasons if the market is bad. We have finished our paper as far as the question of the rubber itself is concerned, but we have still to mention a problem which is met with in connection with solutions, that is, the recovery of the solvents. The liquids most often used are benzine and toluene or a commer- cial mixture of these two substances. Auxiliary use can be made of volatile essences of petrol, carbon tetrachloride and tetrachloride of ethane. 762 But we are only going to deal with the general case and, as above, to give a brief account of an existing apparatus. We owe most of our information to Messrs. Bataille, Monnet and Moyne. - - To warm and dry the cloth covering, it is placed on a table, heated by a circulation of steam. *. + - When the benzine is not recovered, the table is uncovered, and the benzine is allowed to evaporate into the air. It is unnecessary to enlarge upon the economical and hygienic disadvantages of this method. To effect recovery, the cloth should be covered with a cloth canopy which allows the cloth to be taken in and out, and under which there is. a current of air acting as a vehicle for the vapours to be recovered. It is this air, almost a draught, which serves all the time; while warm, it comes. in contact with the damp cloth and mixes with the benzine vapours which are immediately given off, the vapour tension being very low between the temperature of 65° and 85°C. After leaving the warm table, the mixture of air and benzine passes trough a condenser having surfaces sufficiently cold to condense the solvent, and then the air passes through a steam heater to be re-heated and commence the circuit afresh. Obviously the most important part of this apparatus is the condenser, because the air which absorbs the benzine should be in thin layers, in contact with surfaces cooled by town water to 15° C. Here are several figures on the amounts of benzine recovered. If we assume that the cloth moves at 1.5 metres per minute, and it is 1:2 metres wide, we have 1.8 square metres of cloth to be dried per minute. Or according to the solutions used, which are clear in the first layers, and thick in the last layers, from 075 to 150 kilogrammes of the solvent must be removed during this time, or from 45 to 9 kilogrammes per hour. This corresponds to a table 4 metres long. The present tendency is to double this length, thus doubling the rate at which the cloth travels, and hence the quantity of solvent. The temperature of the warm table and of the air admitted might be from 659 to 80° C., as has been said, and from 45 to 50% of the benzine. could be recovered. The cooling liquid used up to the present is town water at about 15° C. What advantage would be derived by artificially lowering the temperature to 0°C. or below? - This is one more question which may well be put before makers of refrigerating machinery, and with this we must conclude our paper. 763 *** Applications of Cold in the India-Rubber-Industry. By H. L. Terry, Engineer, Manchester. Refrigeration is employed for two purposes in the india-rubber industry, one application being in the fine cut sheet or >feuille anglaises branche, the other being in connection with the condensation and recovery of naphta from spreading machines. - - So far as England is concerned probably the best examples of these freezing processes are to be found in the various card-cloth factories in Lan- cashire and Yorkshire, as in their works the refrigerating machinery is very generally installed for the double purpose of naphta recovery and of free- zing the rubber blocks preparatory to their being cut into sheets. Although the method of manufacturing the circular blocks in the card cloth factories differs materially from that followed in the three large rubber works, which imave a monopoly of the cut sheet manufacture in England, artificial refrige- ration is employed in all cases before the blocks are cut into sheets. Alt- hough, however, the application of refrigeration is universal, the procedure was found at the several works shows considerable variation. Pure indiarubber is very susceptible to changes of temperature. While perfectly rigid at a few degrees below the freezing point it becomes increa- singly soft at higher temperatures until the point of decomposition is reached, when it loses its property of being congealed by cold. At such low temperatures as that of liquid air it becomes as brittle as glass though judging by the effect of solid carbonic acid intense cold exerts no chemical or injurious action, its original elasticity being restored on ex- posure to ordinary temperatures. With regard to the requirements of the cut sheet industry a modera- tely low temperature is all that is necessary for the proper consolidation of the blocks to the core. If too great a degree of cold were employed the block would be of uneven consistency, as the Sudden congelation of the exterior would prevent the penetration of cold to the interior, which would remain soff and unfit for cutting. - Perhaps the ideal way of freezing a block is to put it in the open air during wintry weather, but as British winters are very variable, and as the demand for cut sheet is general throughout the year, all the factories have found it necessary to employ artificial means of freezing the blocks. At one time it was quite common for work to be suspended for weeks at a time 764 in summer owing to the softness of the rubber and the high temperature or the cutting room. Now-a-days to the best of my knowledge no such stop- pages occur except in one case where the use of ice and salt still exists as the freezing agent. This is as far as England is concerned: what the case. may be as regards the Continent I do not know. England has of course : now lost her former monopoly in fine cut sheet — though it will be gene- rally acknowledged that her prestige still remains — and seeing that the industry is now well established on the Continent in modern works, it may be that the refrigeration plant existent in English works is somewhat out. of date. This is only a matter of supposition as I do not profess to be ac- quainted with"continental procedure. At the same time though I am open to conviction that English methods do not testify to recent progress in refri- gerating machinery as far as efficiency and economy are concerned, I am not prepared to admit that the quality of the cut sheet produced by the English firms is capable of improvement. My supposition is limited entirely to the possibility of further economy in production. In one case at any rate the refrigerating plant in England is 40 years old. and in several cases it is over 20 years old and it must be understood that as far as this paper is concerned I am merely dealing in a general way with the present condition of affairs without expressing any opinions on the rela- tive efficiencies of this or that plant. I am not in a position to go into details regarding the procedure at any particular works for reasons which will be obvious, but from the general description of the plant in use at the large indiarubber works of Messrs. Chas. Macintosh & Co. Ltd. at Man- chester, and at the card cloth works of Messrs. Hosefall & Bickham of Pend- leton, Manchester, sufficient information will be given to enable those igno- rant of the trade to get a grasp of the matter under discussion. For many years after the initiation of the cut sheet industry by Han- cock in 1820 the refrigeration of the rubber blocks was effected by the well known freezing mixture of ice and salt—the blocks being put into wooden boxes let into the ground. Now however Messrs. Macintosh & Co. have a very complete installation, which includes an ammonia refrigerating plant for the blocks, and also a sulfurous acid machine for cooling the: large workroom in which the cutting machines are placed. The ammonia. machine is situated in a chamber insulated with charcoal, the blocks remain- ing in this chamber for a length of time, which represents a considerable saving compared with that in the ice and Salt age. The workroom is also insulated with charcoal and kept at a uniform temperature of 45° to 50° F. during the summer months, while the water dripping on the knives is main- tained at about 40° F. t -- Sheets of rubber, of which 160 go to the inch are now being cut in hot weather in this room. S. Turning now to Messrs. Hosefall & Bickhams works we find the arran- gements to be rather different. Here the artificial refrigeration of the blocks. 765 by machinery was initiated about 40 years ago, the plant being designed also for the recovery of naphta from the spreading machines. The machine is after Siddely and Mackay's patent, in which ether is used, and was put in by the engineering firm of Arrowsmith Siddely & Co. of Liverpool, welf known at one time for this class of business. The firm, J may say, is now no longer in existence. The naphta is collected from the spreading machines by closely fitting hoods being drawn mixed with air by a pump through a condenser of copper tubes. The brine in the condenser is kept at about 34° F., which is a sufficiently low temperature to effect the condensation of the naphta-vapours with the requisite separation of the air. These machines as put up in this and other card cloth factories have worked consistently well with an uniform recovery of 50 to 60°/o of the naphta used. One drawback has been that owing to oil lubrication the recovered naphta has been unfit to use again directly and it has been sold back to the naphta distillers. In the more modern plants, however, this difficulty is obviated by the employment of a lubricant insoluble in naphta and the recovered solvent is now being used again without redistillation. With regard to the freezing of the blocks at this works the procedure is as follows: - -- A wooden tank 12 feet square is let into the ground and is insulated all round with sawdust. The tank has a wooden cover into which iron cases. to hold the circular blocks are fitted. The tank is filled up to the top. with brine circulating from the refrigerating machine, the blocks of rubber being exposed to its temperature for a definite period. In cold wintry weather the tank is not used, the blocks being placed in the open air in the yard. The brine pipes passing through the cutting room help to maintain a low temperature and the water falling on the knives is also specially cooled. At the card cloth works of Messrs. John Whiteley & Sons Halifax, Yorkshire, a branch of the English card clothing Company Ltd., the same. make of refrigerating machine is used for the freezing of the blocks, though the process adopted differs again from the two, which have been described. As already mentioned, freezing of the blocks in ice and salt still exists - at one works, so it will be seen, that in a limited number of works there are considerable variations in the application of refrigeration for the same purpose in the rubber manufacture. With regard to naphta recovery artificial refrigeration is by no means universal, as some plants are in existence where the condensing water is not specially cooled. Taking, however, the British proofing industry as a whole there are very few naphta recovery plants in existence and I doubt if any of these give such good results as have long been obtained in the card cloth factories by the other machine referred to above. ~ *—sº-º-º-ºsmºsses.<=== 766 Application of Cold in the Leather Industry. Treatise by Regierungsrat Wilhelm Eitner, Vienna. º Though the main material of the leather-industry, Animal Skin, is a very easily decomposable substance, the preservation of which by means of tannin forms an essential part of leather dressing, and which even as raw material must be carefully protected from every influence causing decompo- sition, yet cold was until recently but little applied in the leather-industry, and even then, less for the purpose of preservation, than for quite other purposes. This is explained by the following account: If animal skin is to be preserved by Cold, this can only be effected at temperatures above the freezing point, because skin, cannot bear being frozen as meat is, without suffering in quality and there by becoming wholly or partly unserviceable for most tan-yard purposes. Those animal hides that are transformed into leather contain in their fresh state more than 60 Prozent of water. This, to a small degree, is contained in the vessels and lymphatic ducts embedded in the skin, but mostly in the elements of which the skin fibres are made up that is in the fibrils. When these are frozen, through the expansion which they undergo, owing to the increase of the water volume, they are, in their consistency, partly loosened to bundles of fibres, and partly rent asunder, so that thereby the whole skintissue is loosened and weakened. Leather made of skins that have been frozen cannot be used for Sole-leather, it being for the purpose too spongy; it is not fit for driving belts as it is too easily stretched and torn; nor is it suitable for uppers because it is neither sufficiently water proof nor durable enough. Apart from these hindrances, technical in principle, in the way of frigorific preservation, it would be impracticable from other causes such as the various changes of place, and the different conditions of conveyance and of storing to which hides as a marketable article are subject. Never- theless there is a process of skin-preservation by refrigeration. In the big American slaughter-houses the skins directly after being stripped off the animals, are taken into cooled chambers, where they remain until fit to be weighed. It is generally thought that the skin can be correctly weighed only after having been thoroughly cooled, because during the cooling process, some water evaporates and consequently the skin gets lighter. But in order to minimise the evaporation of the water and to avoid loss in weight, the 767 refrigeration of the skins takes place at once in refrigerating chambers. This refrigeration however, for the above mentioned reason, must not be brought to the freezing point. In large North American slaughter-houses artificially produced cold is employed for the cooling of the refrigerating chambers. Although the raw hides are thus deprived of their natural warmth merely for the sake of preserving their weight, a matter which interests the buyer less than the slaughterer, yet this chilling is of importance for the actual preservation, for the transport and also for the storing. The latter preservation is done with common salt which acts for this purpose in a double capacity. The first part of the debased salt employed is spread on the flesh-side and acts as a water-absorber, so that absorbing part of the water contained in the hide, it dissolves and flows off as brine. By this decrease of moisture in the skin-substance the latter gains in its capacity of preservation for the second salting that takes place later on, the efficacy of which is much intensified by the rapid cooling after the slaughter. This cooling causes the blood contained in the numerous blood vessels to congeal, in which state it is less liable to decompose or by means of the blood vessels to spread decomposition, which in skins, owing to the enormous quantities of the most various kinds of germs deposited in the hair, sets in and spreads very rapidly, if the temperature is above 10 degrees C (centigrade) Therefore, with cooled hides, no decomposition will take place before the salt preservation process, and as this, though it does not sterilize, yet checks the spread of the germs, it is of more certain effect, which, for the practice, is highly important. There is also a possibility of Saving salt, as a smaller quantity of salt suffices for cooled hides than for skins which have already a putrid smell. In our large, up-to-date slaughter-houses which, as a rule, are provided with refrigerating appliances, strict attention ought to be paid to the hides being cooled immediately after the slaugh- tering, and to their being further preserved with salt. In the large slaughter- houses of the Argentine Republic the skins are sterilized before the salting by being hung in closed rooms which are filled with Formic aldehyde fumes. - The skins are, thereby, not only better preserved, which is of great importance as regards deerskins that have to undergo long sea-transport and often also long periods of storing, but experience shows that they also gain in quality and produce a far more solid leather. In the Frigorific-slaughter-houses of the Argentine Republic, which export frozen meat, and which, being amply provided with refrige- rating machines, also dispose of refrigerating chambers for the hides, it is probable that the hides are cooled before salting, just as in North American abattoirs. In fact the Frigorificos sorts of skins show excellent preservation which may be attributed to their being cooled after the slaughter. In the storing of wet salted skins as well as of dried skins and furs refrigerating chambers are highly appreciated. Though the wet salted skins 768 are protected from decomposition by salt, there is still, in the interior of the hide, a possibility of decomposition by anaerobia, which might also occur if the hides remained piled up in heaps in warm localities for some length of time. Such damages of skins in stock were unknown in ancient tanne- ries, as these disposed of stone-vaulted rooms with thick walls which even during the hottest Summer remained cool. In the more lightly built, modern leather factories which generally do not possess refrigerating chambers, an inner decomposition of the hides, if they remain for a longer period of time in warm places, is of frequent occurrence and the damage, arising there- from, which shows itself in the splitting of the leather, may become very considerable, so that proper attention must be bestowed upon the cooling of the respective store rooms. Dried skins, and especially pelts and furs, suffer in warm places from damage done them by moths, particularly by the caterpillar of the fur moth, to a much higher degree than in cool places; efficient protection will, however, only be obtained by the application of in- sect powder or Naphtalin. In the aforesaid I have given an outline of the relations of low tem- peratures to the main raw-material of the tanning industry, animal hides. As we have seen, these relations are now insignificant, nor can any con- siderable increase in them be expected. In actual tanning where the sole object is the transformation of animal skin into leather, differences of tem- perature play an important part, as in every chemical reaction, and one likes nowadays to consider tanning as a chemical process. The degrees of temperature, however, which must be taken into account by tanners, are at present above that limit at which the interest for the «Refrigeration Industry» commences. - The tanning of hides, as is generally known, is divided into two sec- tions: the preparation of the skin for tanning and the tanning itself. In the preparations for making true skins, which is done with the aid of water, the temperature of the water was formerly an important factor, upon which the result of certain operatons were dependent. For certain purposes, e. g., for under-leather, experienced tanners considered that the true skins should be passed through the same water in which the hides had been cleaned (soaked), it should become hard and stiff. For other purposes, e. g., for upper leather, the contrary effect was aimed at, the true skin should become soft. The former effect was obtained by applying cold water of less than 12° C (Centigrade) the latter by applying warm water of more than 18° C. As, however, nearly all mechanical working operations on true skin can be accomplished in its soft, mellow state, that is after applying warm water (24° C) which latter temperature is easily obtained by heating the water with steam, the formerly not unimportant question of an equable temperature is solved for all those tanyards which use steam. I have men- tioned before that with true skins destined for sole-leather, it was deemed necessary for their solidity that they should proceed from the water treat- ment as tight and stiff as possible, a result which is only to be obtained after treatment with cold water, owing to the special effect of the adhesive substance of the skin fibres. Because of these old-fashioned ideas sole-lea- ther tanneries used to be formerly erected only at places where there was abundance of natural cold water throughout the whole year. Besides the purpose of making the leather hard, the cold water had also to act as a kind of natural antiseptic for a certain sort of sole-leather, namely in the sweated sole-leather manufactured on the Rhine and the Moselle. The hides from which this sole-leather is produced, are made to sweat by a special, regulated and Superintended process of disintegration which is effected under evolution of heat. The progress of decomposition being dependent upon the temperature of the surrounding medium, it is regulated by changes of temperature, which generally means that the tem- perature raised by spontaneous heating has to be lowered. This cooling off is obtained by cold water or air cooled by ice, in recent times (in America) also by the aid of refrigerating machines. As this sweating process which consist in a partial disintegration of the epidermis through putrid ferments, infects the hide all over with these ferments a sterilization of the same, before it undergoes actual dressing is necessary, which was recognized before the idea of sterilization was conceived. To free the skin from decomposing products caused by the Sweating process and from the putrid organisms the true skins are suspended in running cold water and allowed to soak, which operation takes from 2 to 6 weeks, according to the temperature of the water and its fall. This very primitive sterilization which was often frustrated by sudden change, can now be replaced by a chemical process. Chloride of lime, sulphurous acid, thiosulphate and hydrochlorie acid, as also formic aldehyde, applied in proper quantities, are effective sterilizers rendering the skin in but a few hours, free of germs, without impairing its capacity for dressing. The application of acids or acid salts, leads to the so much favoured hardening of the true skins, which was formerly only gained by using low temperature water for soaking. In the actual tanning, that is the transformation into leather of the cleansed, but still raw true skins, temperatures below 15° C exercise an unfa- vourable and retarding effect on the combination of the skin with the different kinds of substances used for tanning, and this from various causes. In Shamoying the reaction caused takes at a temperature of 25–35° C, this, consequently being the only proper temperature for such tanning. Glacé leather is dressed in alum-tan which shows a temperature of 35° C, and also the other mineral-tanned sorts of leather, especially chrom-leather, are warm tanned, because the tanning turns out quicker and richer, as the reaction is favoured by the heat. Also in dressing bark tanned leather, temperatures below 15° C have a retarding effect, which increases as the temperature sinks below 15° C, whereas the effect is accelerating if the temperature exceeds 15°C, which, however, can be practically utilized only 49 77O to certain limits that are fixed by the kind of skin, the phase of the dressing and the sort of tanning substance. In vegetable dressing it is not only the reaction between hide and tanning substance, from which depend duration, intensity and kind of dressing, that is influenced by the temperature, but also the solubility of the different vegetable tanning substances and conse- quently their effectiveness. Naturally enough higher temperatures dissolve the tanning substances more easily and thoroughly and admit of a more thorough utilization of the tanning substances than do low temperatures. The tem- peratures to be taken into account whit tanning substances exceed 1000 C; the close relation betwen the greater or lesser solution of the vegetable tanning Substances and their capability of reaction on the skin is obvious. The different degrees of reaction and solution which are influenced by temperature are used to regulate the tanning process by commencing tanning at a low temperature and finishing at higher temperatures. The first stage of the tanning, is commenced and worked more gently in order that the final stage may be quicker and more intense. An artificial cooling of the tan-Ooze does not take place here, on the contrary, a heating by steam, if Such appears necessary. In the tanning liquors prepared with vegetable tanning material, not only is there a tanning substance but also other substances which as hydro- carbonates serve as substratum to different fermentations. Of the fermen- tation products which here are developed, it is the organic acids, viz. acetic acid, lactic acid and butyric acid which are looked upon as important aids in the dressing of soleleather, and the formation of which is consequently furthered. A regulation of the temperature serves here as e means of fur- therance, and, curiously enough, this furtherance is attained by a lowering * of the temperature, whereas, on the other hand, the fermentation of the above acids is furthered by temperatures above that of tanning; only lactic acid forms an exception. The above strange effect is explained by the fact, that in the tan-ooze, owing to the presence of foreign ferments and an undissolved skin substance as substratum, fermentations other than acid may, under certain conditions, take place. By these additional fermentations which increase in intensity at temperatures from 18°C upwards, and which may choke up the acid fermentations, not only the intended effect, the swelling of the skin by acid, is changed to the contrary, that is a decay of the skin, but the skin itself is attacked which may within a few hours’time, result in its perforation. This so-called reverse by the tan-ooze, and even a lesser degree of this evil, the growing dullness of the same, was greatly dreaded in tan-yards and it occurred particularly where the sweated skins were only cleaned by soaking and insufficiently sterilized so that the ferments of the false fermentations got into the ooze. The uncleanliness prevalent in many tanneries in former times, furthered this evil. Owing to this change, and also because of the insufficient efficacy of the swelling liquors, it was custo- mary during the warm season for the skins not to be worked, or that 771 the rapid colours which had to be kept should be cooled. This was done either by pieces of ice which were put into the ooze, or by artificial cooling. An ice-shed was built adjoining the room in which were the rapid colours. This was isolated by waste tan, or it was dug right into this tan, to pre- ‘serve the ice from melting. • These ice-sheds, used already in ancient times in tan-yards, may have served as models for the American ice-cellars which came to us later on. In case of need a connection between the ice-shed and the temperature was established, by which means the room was cooled and the temperature of the tanning-liquor lowered. That would have been the proper place for a modern refrigerator. Unfortunately or fortunately, as the case may be, this is no more needed thanks to the chemical sterilization of the sweated hides. It has also become unnecessary because the dangerous fermentations which occur in the beginning of the tanning-process are now removed and organic or mineral acids, bought ready made, are now used for the swelling of the hides. - The cleanliness that prevails now in our modern tanneriers enables us to do without artificial cooling even in the summer months. For the sake of curiosity and completeness I will mention another application of intense cold that was practised in by-gone days. I have already observed that at low temperatures the tanning process was imperfect and slow, which in winter time tanners often experienced to their grief. When, now, imperfectly tanned leather was used in winter, the so-called «tanning of Saint Simon.” was had recourse to, which consisted in exposing the leather to serve frost. Through this, freezing of the half tanned leather the same effect was attained as in cooling raw hide, namely that of the fibretissue being loosened and the leather there by appearing soft and mellow. The leather was, however, not durable and could not be sold by the weight, because void of substance. From the aforesaid it becomes evident, that in the actual tanning process the temperature at which it takes place, is of great moment, and, that the serviceable degrees are above 12° C. Lower temperatures were formerly applied only for the maintenance of the thanning-liquors of a certain sort of leather, for the purpose of swelling under simultaneous pro- tection of the skin. Now the modern leather industry, in another state of the working process, opens up a more productive field for the application of refrigeration. Where as formerly the parts of the plants containing a tanning substance were directly used in dressing raw skins, the modern tan-yard cuses the tan extracts prepared from these parts of the plants, which extracts are either prepared in the tannery itself or manufactured in special eta- blishments the methods of procedure differing in each case. First of all we must try to exhaust as far as possible the contents of the raw material of valuable substances, which must be considered the object of every extrac- tion, further, the tanning substance must be as pure as possible, that is, free from accessory stuffs, which, in soluble form, are contained in the 494. 772 plants together with the tanning substance, and which, therefore, are ex- tracted at the same time. Finally, and this is especially important, the colour of the extract should be as light es possible, for the reason that the leather as a rule is to be tanned in lighter colours, because light extracts dissolve more easily in water, and, therefore, penetrate more easily into the skin-tissue, and, moreover, light extracts are best utilized. The fabrication of the tanning stuff extracts, according to the above mentioned conditions to which the quality of the extract is subject, is divided into two parts, the first of which is the obtaining of the extract from the material, the second, the cleaning, clarification and decolouring. Extraction, as well as purification, are in close connection with the tempe- rature, so that here great use of the latter is made. The solubility of the tan substance of the various materials is different; many of these materials contain, however, various tanning substances, the solubility of which also varies, that is, the temperatures at which their solution is effected relatively greatly differ. The tanning substances soluble at low temperatures and therefore easily extracted, are generally the light ones and the more appreciated, where as the tanning substances hard to dissolve are the dark ones. In extracting the tanning materials, which is done either in open maceration — or in closed diffusion — batteries, the extraction takes place either at lower temperatures (about 60° C) which occurs whit materials containing easily soluble tanning substances, and in those cases where clean, pure liquors and lighter tanning substances, are aimed at, or the extract factories which require thorough lixiviation and besides, liquors as concentrated as possible, must employ higher tempera- tures, even boiling heat and still higher degress of heat under pressure. With an extraction of this kind, which is very exhausting, especially with materials which contain the most insoluble derivatives of the tanning sub- stances as is the case with tan woods, these derivatives are extracted under pressure. They separate, when cooling, in the shape of resinous bodies and pollute the extract. The purification of these raw extracts is sought for by different means, namely by precipitants, by means of which those mostly suspended, hard soluble parts are swept along, whereby a loss of Serviceable substance is of frequent occurrence. The purification can also be effected by applying alcalic salts as a means of solving the not easily soluble colouring matter, whereby, however, extracts are obtained which possess less of a tanning than of a dyeing capacity, and finally also by sulphites and bisul- phites which operation yields light tanning though not very profitable extracts. All these deficiences of the above mentioned extract-clarifying methods can be avoided by a process which is based upon the application of refrigeration and which has been patented by Dr. A. Redlich. Dr. Redlich's process consists in extracting the broken- up material, best Quebracho wood, under pressure, and cooling off at once the thus obtained lixivial ooze to below 10° C. By this rapid cooling off, the resinous colouring stuff, only 773 soluble at temperatures above 100°C, is segregated in coarse flakes and with it, gradually, the otherwise hardly separable substances. This process gives extracts not only light, because freed from the colouring matter, but also cold, clear soluble extracts of great tanning power, as their tanning substance undergoes no change in the purification. Such rapid and extensive cooling off, can, in technical working, only be arrived at by using a specially constructed refrigerating apparatus with refrigerating machines, such as built by the Brünn-Königsfelder machine- factory. This last method of extract-clarification forms, till now, the most important invasion by artificial cold of the leather industry, by which it wilf certainly be recognised. 774 Importance and Application of low tempera- tures in the Textile Industry. By Dr. Franz Erban, Vienna. We should but incompletely picture the uses of cold in industry if we omitted its use in the textile branch. Twenty years ago I was a yonng chemist and my principal was a colourist of the old school. When I told him that I wanted ice to produce the Naphtylamin-Azote colours, at that time just coming to the front, he considered this foolish play. To-day no printing works and no dye-works can be called modern and efficient which has not at all events an ice cellar. It seems to be in place, therefore, to devote a few words to this branch though it is somewhat separate and foreign. - I Use of cold in obtaining the fibres. As yet low temperatures have scarcely been brought into use for obtaining animal fibre stuffs, and the delay effected in the creeping out of the silk spinner and destruction of the worm — for which according to Lovado, one month's storing at 0° C suffices — caused by cooling the cocoon belongs in reality more to the sphere of farming than to the textile industry. As trial of the use of cold in obtaining vegetable fibre stuff, we would mention the process of Stotz, D. R. P. 130,979, concerning the removal of wood from frozen Ramies (Rhea) stems, after twelve hours' cold storage; yet the work must be done as quickly as possible as the effect does not continue after the thawing (>Lehnes Färberei-Zeitungs, 1902, 194, and • Deutscher Färber-Kalenders, 1910, 49). Similar in principle is the process of Bertrand Summers, Port Huron, D. R. P. 197.659. It recommends that flax and hemp be first warmed to between 20° and 100° C, then sub- jected to a temperature of between 4° and 18°C and that in frozen state the removing of the wood be immediately effected. (Leipzig, Monatsschrift für Textilindustries 1908, 6, 172). The process is said to have proved suc- cessful for Rhea, but probably offers little or no practical advantage for flax and hemp. - 775 Practically it is still an open question as to whether the spinning qualities of fibres are permanently changed by the passing influence of severe cold. -. Low temperatures seem to play an important rôle, on the other hand, in many processes of making artificial silk from collodium solutions. Viscose and other cellulose derivates. But it is difficult to obtain definite data owing to the strict secrecy observed by the respective factories. Certainly cooling is essential in the nitrating of cellulose, and in steeping the wool in copper oxide of ammonia (D. R. P. 98.642 of Dr. Pauly and 109.996 of Dr. Bronnert); also in making viscose silk from cellulose canthogenate. The use of cold is also said to be of advantage in the manufacture of the wires for incan- descent lamps. II. The use of cold in mechanical Manufacture. As regard the mechanical manufacture of textile fibres in spinning and weaving, we have rather to do with a damping than with an extreme cooling of the air and the material. By practice we have got to know that too low temperatures decrease the suitability of cotton for spinning purposes, as the wax coating formed by the natural fat then becomes hand and brittle. The cases of greased wool and of fat filled jute are similar. Sized warp does not work well either, in rooms that are too cold. Rothwell made an exhaustive study of the influence of cold on the strength of cotton (see Lehnes 2Färberei-Zeitungs 91/92, S. 406 and 92/93, S. 75). He found that the freezing made the fibre hard, brittle and fragile, but that after thawing and drying no evil effect remained. This was, howe- ver, only the case when the freezing did not take place suddenly causing the fibres to tear and burst. III. The application of cold in the chemical branches of the textile refining industry. While Rothwell's experiments showed that the mechanical properties of fibres, especially those of cotton, were not permanently altered by freezing, experience has shown that a freezing of the water contained in damp textiles is unfavourable for the equality of later dyeing, especially with sulphurous colours. (Brunner, *Monatsschrift für Textilindustries 1906 Heft 17–23) It is interesting to notice that in goods which contain slightly sour dyeing matter the acids still remaining liquid are concentrated on the fibres by the freezing process. This may lead to spots in the case of delicate colours, and in vegetable fibres a sort of carbonisation sets in, while on the other hand, by too great cooling of a fibre impregnated with Salt Solution, a perforation of the cell membranes may result from the crystal formation. * 776 A) Prep a ring and Cleaning Processes. Cold is sometimes made use of in the processes of preparation and. purification that fibre stuffs undergo. The chloride of lime solutions, used in bobin bleaching, after older processes, are generally cooled with ice, to prevent danger of injuring the fibres by cellulose formation, when strong solutions are applied for longer periods. In modern, rational bleaching this evil is avoided and the cooling of the chloride baths may be dispensed with. We may here mention the Bickel process. After a Pli cacheté 1032, deposed in 1898, opened at the assembly of the Soc. Ind: Mühl. of 6* Ja- nuary 1909, Bickel described a process of making a chloric hydrate by electrolysis with the aid of cooling for bleaching purposes. (Lehnes • Färb- Ztg.< 1909, 144, Försters •Zeitschrift für Elektrochemies 1899, 6, 15.) When, about 15 years ago, Messrs. Thomas and Prevost at Krefeld, applied the mercerisation of cotton goods with concentrated lyes industrially (cp. D.-R.-P. 85,564, later annulled, Öst. Woll-u. Lein.-Ind. 1899, 934), whereupon the problem of mercerising experienced a thorough elaboration, it was seen that the colder the lye was kept, so much the better were the results attained and so much the weaker could be the lye employed. Since the content of the impregnation trough is gradually raised in temperature by the reaction warmth, it is necessary to cool it by using double walled troughs or by circulating the lye through a cold vessel (Simon in Villefranche provided his mercerising machine with coolers and lye circulation (cp. Lehnes »Färb.-Ztg.< 1900, 109 und 219). Ice or ice water is much used here as an aid, but the most rational method is to make use of a small ice machine. For this purpose carbonic acid machines are not to be recommended, be- cause in case of leakage the carbonic acid which streams out will be ab- sorbed by the lye, and the mercerising effect must suffer through the change of the effective alkali into ineffective carbonate. Such leakage would not be immediately noticed with carbonic acid, but with ammonia the least lea- kage would be immediately evident through the smell, and ammonia would not damage the lye either. According to the description of the Öst. Priv. v. 8. June 1896 a lye of 10–12%. Be should be used. This does not cause shrinkage at ordinary temperature, so that the goods may be impregnated with the lye without trouble. The mercerisation does not take place until the goods stretched on a frame are cooled below 0°C; as soon as the lye gets warm again, the tension gives and washing may be effected in the usual manner. (Lehnes »Färb.-Ztg.< 1897, 273.) The use of cooled lyes in mercerising also forms the subject of a P. A. 5091/1899, for which the firm J. P. Bemberg, at Barmen were granted D.-R.-P. 112,773. Klein of Dusseldorf in D.-R.-P. 122.433 (cp. Lehnes • Färb.-Ztg.< 1902, 126, recommended mercerisation with lye cooled to 2° C, followed by wash- ing with hot lye to remove the tension. ... --> = 777 Tagliani in 1907 took out a D.-R.-P. 107,916 for a one sided mercerisation by means of splashing with cooled lye, and in 1900, A. Schäffler constructed a suitable ºfculards for carrying out this process, the trough and rollers of which could be cooled by liquid Carbonic acid to below 0° C. He patented this D.-R.-P. 131,134 and 131, 128 (cp. 27eitschr. f. Färb.-Ind.< 1902, 219 and 1903, 60, 69). What has already been said above applies also to the use of liquid carbonic acid. While this cooling of the mercerisation lye principally effects a saving of caustic soda in cotton, it is of chief importance in mercerising mixed stuffs, half-wool and half-silk, since otherwise animal fibres would be severely attacked by the lye. In mercerising half-wool use is made (according to data in Lehnes Färb.-Ztg.< 1900, 133) of lyes of from 10–30° Bé between 3 and 10° C, and lye and acid troughs and wash water are all cooled. The period of application is from 1 to 3 minutes, and the machines of Schäffler may be used to advantage. As regards the question of the advantage of cooling in consideration of saving of lye and effect attained, various opinions are held by experts. Thus Lefèvre (in Lehnes • Färb.-Ztg.< 1902, 31) explains that with a 359 Bé lye at 15–20° C he achieved very good results and in consideration of the slight reaction warmth a special cooling was neither necessary nor of ad- vantage. On the other hand, in a reply signed E. Sch. (Lehnes • Färb.-Ztg.< 1902, 68) it was maintained that even with 40° Bé lye the cooling had a favourable effect, in as much as the mercerisation went forward more quickly enabling sharp pressing and consequent 40% saving of lye to be carried out, whilst the addition of temperature with wide goods amounted to 20°C without cooling. C. Kurz considers cooling to be necessary for mercerising unbleached raw goods on account of the great heating that takes place (Lehnes >Färb-Ztg.< 1902, 31 and >7eitschr. f. Farb.-Ind., 1902, 143); so, too, for working with weak lyes, whilst with strong lyes between 0° and 20°C on the other hand, he could ascertain no noticeable difference in the gloss, whereas at 40—60° C the difference is very marked. Lefèvre, on the cont- rary, repudiated the mercerisation of raw goods (Lehnes • Färb.-Ztg.< 1902, 81) and declared that cooling was only necessary with 15–20° Bé lyes, and with 35° Bé was superfluous. The question of the influence of temperature on the result of the mercerising process was lately discussed again by Lester (Lehnes >Färb.-Ztg.< 1909, H. 24) and by R. Bude (Lehnes • Färb- Ztg.< 1910, S. 81 and • Geraer Appretur-Ztg.< 1009, 415). Renewed experi- ments by Petroff (see Lehnes "Färb.-Ztg.< 1910, 230) show that the cooling is of influence on the shrinking, the strength of the threads and intensity of the dyeing: the colder the better. A 27 Bé lye has as good an effect in cold as has a 329 at ordinary temperature, In Lehnes • Färb.-Ztg.< 1904, 384, Hübner and Pope published the results of experiments on the influence of weak lyes in cold on the dyeing power Fresh experiments by Knecht (Lehnes • Färb.-Ztg.< 1908, 323) give a conclu-. 778. sion on the cause of the favourable effect of low temperatures. He found that through the drying of the mercerised cotton at high temperatures their affinity for dye stuffs was again considerably reduced, so that even the finish- ed, mercerised, washed cottons suffered a permanent change — anhydri- sation — which could not be overcome by repeated damping. I would not omit, however, to refer to one other case in which, apart from all theore- tical differences of opinion, work with cooled lyes is to be preferred in prac- tice. I mean the mercerisation of goods with bright colourings, in which, naturally, the colours are so much the less attacked the weaker the lye used can be, the colder it is and the shorter the period of application, when, too, easier washing and weaker souring are of advantage for the preservation of the colours. t The questions are of interest theoretically, and of practical importance as to the influence of cooling on the capillary speed and rate of diffusion of the lye, and on the coagulation when soap, caramel, or humous impu- rities are present. The great importance played by mercerisation, to-day, in the refining of vegetable stuffs makes it appear quite natural that this matter should form the subject of a special paper by Dr. A. Kirchacker. Another operation, also belonging to the preparation process is the weighting the silk with solutions of chloride of tin. Here, too, experience has shown that the colder the tin bath is kept the better is the working, not only as regards the making full use of the tin, but also as regards the weighting effect and the lasting quality of the silk fibres. Experiments made by Dr. P. Heermann on the influence of cold on the mordanting process in silk and its behaviour towards the salts of tin, iron, chrome, and aluminium, showed that these especially the first two, become very thick in cold and diffuse very slowly if temperature sinks below 5°C. (cp. Lehnes • Färb.-Ztg.< 1903, 117, 142). As cooling with pieces of ice cannot be used in these processes on account of the dilution, most large silk dye-works have ice machines with which they cool not only the tin solution in the store vessels, vats and Montejus, but are also able, by joining a conduit cooler in the circuit, to continually reduce the tin solution, that circulates during impregnation of the silk, to the original low temperature. For this ammonia machines may be used if these ice machines are in an entirely separated room and if only calcium chloride solution or glycerine water is circulated in the cooling con- duits. Carbonic acid machines, however, are preferable, if they can stand in the work-shop itself, or if the expansion conduits are directly used for coo- ling, because the presence of ammonia in the air of the work-shop will render the weighted silk lustreless and raw, and above all the absorption of ammonia by the chloride of tin would render it dull and useless, whereas carbonic acid can cause no harm in any direction. 779 B. Dye works and Print in g-w or ks. Dyers have long known that the colder the dye-bath at the beginning the better the uniformity of the shades, particularly in bright colours and for colours on tannic mordants, but ice pieces were generally made use of. A large Swiss dyeworks for red shades had, formerly, quite a mono- poly for uniform light pink, and the secret of the success lay in the fact that this factory made use of the water of a mountain spring of between 40 and 50 C in preparing the dye baths. - Of far greater importance to dyeworks and priting-works than these appli- cations of cold for delaying the colouring of mordant dye-staffs have those processes now become, which deal with the making and application of com- positions that decompose easily at higher temperatures. We may consider the so-called ingrain colours as forerunners of these processes. These colours were produced by dyeing with Primulin, treating the dyed goods with nitrite and acids and developing with naphthalene sodium or some other phenylic acid etc. With these it was found that the purest red was obtained if the nitrite bath and the following washing and developing baths were kept as cool as possible by adding ice, and again, that this, prevented the formation of discoloured and troublesome decomposition products. Since the first trials were made, about 20 years ago, to produce Azote fast dyes on the thread from their component parts, two such, especially, have developed to general articles of trade, namely Naphthylamine Bordeaux and Nitranilin red. The production of these articles now amounts to many hundreds of thousands of kilogrammes, and millions of metres annually. These dyes are generally applied in the following manner. The threads are stained with one component, the naphtholene Sodium, and then coloured or printed with the so-called diazote body, the middle product obtained by treatment of the respective aromatic base with nitrite and acids. Now the production of these diazôte bodies requires the most energetic cooling, as otherwise the process does not turn out satisfactorily. The storing of the prepared dye-baths and printing colours must also be done with good cool- ing, in order to prevent a premature dissolution. Large printing-works re- quire considerable stores of ice therefore, inasmuch as the cooling of diazotes is chiefly effected directly by the addition of broken ice, since metal vessels are generally impossible on account of the dissolving effect of the nitric acids and the influence of the metal salts formed on the shades, and earthen vessels would be too bad conductors of heat to make a rapid cooling from outside possible. Where the necessary quantity of ice cannot be cheaply obtained in winter, it is to be recommended that small carbonic acid machines be put up, which not only produce sheet ice for the pro- duetion of the diazote solutions, but make it possible, also, to cool the troughs of the printing machines and dye tubs, so as to keep their contents good as long as possible and at the same time to maintain an even tempe- 780 | rature in all parts of the room in which the production of the diazote bo- dies, solutions and dyes takes place (the so-called "Eisfarbenküches, ice- colour-kitchen). It is true it would also be easy to cool the printing rollers themselves, by using hollow axles with stuffing boxes and rubber tube connections, but So far as I know no printings-works has such a cooling arrangement. (We may here remember the Austrian patent 42,017 of Weiding for the cooling of ice-colours.) The great need felt by modern dyeworks and printing-works will cer- tainly lead to large production of ice-machines, if suitable types can be placed on the market at favourable prices. - It must not be forgotten, however, that under some circumstances even cooling may be overdone, iu as much as the rate of mixing as a chemical reaction depends in another way upon the temperature of the diazote body to that of the rate of solution of the naphthalene sodium, which concerns its extraction, thus by using too cold developing baths worse results, and thin and slightly fast colours may result. Experiments on the rate of mixing of azote bodies have been scarce so far. (We have those of Goldschmidt and Keller — See Ber. d. Deutsch. Chem.-Ges. 1902, 16, 3.534). Printing colours, too, may suffer in uniformity through the use of too low temperatures, for the thickening turns to a viscous liquid and cannot equalize quickly enough. In any case this is a question that deserves the attention of practical colourists. Director Ritterman will deal specially with the preparation of ice-colours. I should also mention the unfavourable influence of too low tempera- tures on the oxidation process, especially in aniline black dyeing and prin- ting, the cause of which lies chiefly in the separation of crystals, which redissolve with difficulty, or not at all, when later on the temperature rises. The precipitation of crystals may also occur with other colours, if they are too much cooled. C. The or e ti ca 1 and scientific experiments, W. P. Dreaper and A. Wilson carried out experiments on the influence of the temperature of the dye-bath on the purity of the colours obtained, for the interval of 18° to 100° C. It was found that in the cases of cotton and silk the purity and fastness of the colours increased with the temperature. According to Saget the affinity of viscous silk for the dye-stuffs sinks with the cooling more quickly than does that of cotton, so that mixed materials may be dyed in uniform or shaded colours according to the tempe- rature of the dye-bath. - Temperature also plays an important rôle in the dyeing of materials made of a mixture of vegetable and animal fibres. The affinity of dye- stuffs which impregnate both fibres decreases during cooling and increases during warming more rapidly for animal fibres than for vegetable fibres. 781 The fact that colours are more proof against light in cold air than in warm air has many causes: In so far as the fading of the colours is a chemical process, its rate will be increased by higher temperature. Accor- ding to experiments made by A. Scheurer (Lehnes • Färb.-Ztg.< 1909, 33), the moisture of the air also plays an important part, the colours keeping much better in dry air. As cold air is drier there is in it also a cause of the colour lasting better. If, on the other hand, the fading is a sublimation process, then, self-evidently, it will proceed more slowly in low temperatures. The influence of great cooling on dye-stuffs was studied by J. Schmid- lin (Lehnes • Färb.-Ztg.< 1905, 77) and he found that dyed fibres were not changed thereby, whilst many dye-stuffs in solution greatly faded. A pro- blem that often occurs in practice is the preserving of the dye-fluid at a constant, low temperature. The requisite cooling, or the requisite quantity of ice may be easily calculated by taking a constant minimal caloric concentration as basis and applying the formula that I developed and mathematically proved in part 2 of my book: *Theorie und Praxis der Garnfärberei mit den Azo-Ent- wicklernº, Berlin, Springer, 1906. The equations for the concentrations are transferred to the content of the heat calories and the requisite completion thus ascertained, which with the aid of the formulas and tables given offers no further difficulties. D) Purification of w a ste water. Finally reference shall be made to the fact that for purifying waste water from textile stuffs, especially if it contains fats or soaps etc., it is of great use to cool at least to below zero, in so far as this can be effected by means that are not too expensive — say with the aid of graduation work, irrigation towers or other arrangements that permit of a cooling by way of expansion. I may dispense with a further elaboration of such methods, as Dr. C. Feuerlein who has made a thorough study of the sub- ject, will himself refer thereto. An application of cold in oil-gas producer plants. By J. Reidrer, Engineer E. P. C. Paris. The object of this paper is to call attention to the services which may be rendered by the use of a refrigerating machine in oil-gas producer plants. Everybody knows, having suffered them, the inconveniences, (which show. themselves most particularly in spring and autumn) due to obstructions in the oil-gas pipes, in the lamp-posts and subscribers’ branch pipes. The only remedy in this case is to run in haste to the nearest gas company, to prevent a stoppage of gas; several hours afterwards, sometimes 24 hours, and even 48 hours afterwards, an employee in a cap, armed with a pump, a key and a little pair of pliers, presents himself at the house of the victim subscriber, and proceeds to p G < k ==T--~~ Sº or or tº ºr 6- ºr or -d- or or 25 or or or -o- or or . --Hº : A -- §: *. -v - : B i r | ! P C Plan Through M. M. Ž7 Sectional Elevation through O. P. E. Gas inlet passage. S. Gas outlet passage. A. Covering for the apparatus (non-conducting). B. Central division, dividing the apparates into two compartements. C. C. Devices formed by tubes, (inside of which the cold fluid circulates) covered by a thin plate pierced with apertures through which the gas passes. . Arrows indicating the direction in which the gas passes. r, b, c, d. Passages through which the cold fluid circulates in flowing from a to b and c to d, trough. the tubes C in an opposite direction to the movement of the gas. G Below is given the number of calories to be extracted, in order to: treat one cubic metre of gas. Suppose the gas is taken at 16° C and we propose to cool it down to 1" C. We would have (1) to absorb the calories due to the specific heat of gas cooled from 16° C to 1% C, and (2) those due to the condensation of the liquified products. The calculation of the first quantity is easy, that of the second quantity reduces itself practically to the determination of the relative heat of condensation of the water vapour present in the gas. In fact, hydro- carbons of the benzine group are not present in the gas in sufficient quantities to give any deposit above about 10° C, the average preportion in one cubic metre of gas being 35 to 40 grammes of a mixture con- sisting for the most part of benzine and toluene. As for napthaline, which we particularly desire to get rid of the gas is relatively more highly charged, because it is not rare, according to the way in which the distillation of the oil is carried out; according to the arrangement of the oil employed, and lastly, according to the arrangement of the condensing apparatus in the plant, for the gas to be saturated, or almost saturated at the temperature of the surrounding air; but, then thanks to the smal vapour pressure of napthaline, the quantities which the - - - - - ------- - 785 gas could thus contain are of very small weight, and do not exceed ... some decigrams per cubic metre in the most favourable cases; often even when the condensation in the plant has been well conducted, there remains at least one decigramme. Improbable though it may seem,” these small quantities are sufficient, under suitable atmospheric conditions, to cause dislocations in the distributing system, which are quite inadmissable. In the calculation upon which we are engaged, there is, then, no need of taking into account the heat developed by the condensation of these small quantities of napthaline, because it is absolutely negligible. The great expense is then, the condensation of the water vapour, the gas is equally saturated with it, because it comes into contact with water in the different apparati of the Plant, and between 16° C and 1" C as in the case selected, it will deposit about 8 grammes of water per cubic metre of gas. We can say, then, that for one cubic metre of gas it would be necessary: to cool the gas by . . . . 0.35 x 15 calories = 52 calories to condense the water by . 8 x 0.6 calories = 48 calories 100 calories Thus a plant, producing 1000 cubic metres of gas per hour, would absorb in one hour by such an apparatus: About 10,000 calories. The quantity of napthaline deposited would be from 100 to 200 grammes per hour; this small quantity makes it conceivable, that an apparatus grating of an area 4 metres by 4 metres or 16 Square metres, of surface, in each trap, would be able to work several days before it needed cleaning, The quantity of water deposited is about 8 kilogram per hour and pours out continuously. If we employ water as the cooling fluid, supposing for instance that cold water goes into the apparatus at 1° C and leaves it at 9% C, it would absorb from the gas 8 calories per Kilogramme; and it would then be necessary in the selected instance to circulate 1250 litres of water per hour. By increasing the number of grating devices, better utilization would be obtained of the refrigerating power of the cold liquid, which would allow of reducing the power of the circulating pump. From what is stated here, it can be seen that such an installation approximately corresponds in power to an ice-making machine having a capacity of 100 kilogrames of ice per hour. Is is clear, that, if special conditions made it necessary, to lower the temperature below 0°C, to 5° C for instance, it would be a very simple matter, the temperature of the cold liquid entering the apparatus would be regulated to -5°C, and an apparatus consisting of several traps would be Yº. * 50 86 used, arranged in such a way that water deposited upon the first grating: at a temperature still above 0° C could be removed with these parts os the apparatus of a temperature below 0°C, in order to avoid the waste of heat caused by the freezing of a relatively large quantity of water. . . . Summing up: it may be said that, from a technical point of view, the proceſs which we have just described seems very superior in efficiency * to all the other processes proposed, and of which several have been in use in various plants for a number of years; from an economical point of view its practicability depends upon the price at which refrigeration could be obtained, under the conditions of the problem. This is a problem which the work of the Congress will, without doubt, aid in solving in a satis- factory manner. 787 Application of Refrigeration to the Electric Accumulator Industry. By L. Jumau, Paris. The question of temperature plays a very important part, as well in the manufacture of electric accumulators as in their working. This part is a very complicated one, and if for certain operations particularly in the manufacture of plates, it is advantageous to work at a low temperature, in other cases it is the very opposite, and a high tempe- rature becomes better. In the same way during the working of the ac- cumulator, temperature has a different influence upon different factors, some being favoured by a high temperature others by a low temperature. A complete study of the question, besides being very extended is outside the scope of this paper. Also we will content ourselves here with examining the somewhat numerous cases in which low temperatures have a favourable effect, and in which it is advantageous to apply refrigeration. We would refer those who are interested in the general question to our work upon electric accumulators, in which we have treated upon this question in detail, (L. Jumau: Les Accumulateurs Electriques – H. Dunod & E. Pinat, Pub- lishers.) It is not only in its effect upon local action while the accumulator is working that advantages are gained by refrigeration. It is well known that an accumulator loses apart of its charge while at rest, resulting from various reactions which are described as local actions, and which cause the discharging of the plates without the production of corresponding electrical energy. The most important of these local actions is the direct attack by the sulphuric acid upon the spongy lead, an attack which is more rapid as the acid is more, concentrated and impure, and also as the temperature is higher. A decrease in the temperature then, would reduce local actions; the practical result upon the elements of the accumulator being a longer retention of the charge. Unhappily such an ope- ration is not to be considered, because, apart from its cost, it would be disadvantageous from other points of view, especially where the capacity of 50% 788 the elements is concerned, which it would diminish by quite a large pro- nortion. Besides, even at ordinary working temperatures, a well made ac- cumulator only suffers local actions of very little importance, and if it should remain for a long time out of action, there are other means of re- ducing these actions, such as, for instance that of diminishing the concen- tration of the sulphuric acid. On the other hand, an application has been found for refrigeration in the manufacture of the grids, and during the period of forming the positive grids. In this connection we can give an idea of the complexity which we mentioned above, while speaking of the general influence of temperature, ~ by remarking that we are here only concerned with a certain type of posi- tive plate, a plate having a large surface, undergoing a certain method of forming, namely electrochemical forming. The lowering of the temperature would, in fact, be disadvantaegous during the forming of anode plates, and also during the formation of positive plates by the Planté process. For this last, even warming the forming batteries has been resorted to. When large surface positive plates are being formed by the electro- chemical method, a solution containing sulphuric acid, and certain other substances besides, is taken as the electrolyte. Among these substances the most commonly employed are salts such as nitrates, chlorates and per- chlorates, whose combination with lead forms soluble salts. These combi- nations tend to render the anode easily attacked, and to dissolve the lead, while the SO, ions which are liberated, also tend to precipitate the lead as insoluble lead sulphate, which undergoes subsequent transformation, by the current, into lead peroxide. If the ions forming soluble salts (NOs and CLOs for instance) came to the anode in numbers too large in proportion to the number of SO, ions, there would be precipitation of lead outside the plate, and this would be strongly attacked. If, on the contrary, it is the SO, ions which predo- minate on the anode, the plate would be convered rapidly with a thin layer of lead sulphate, which would be transformed into lead peroxide, and the plate would have but little capacity. To obtain a layer of peroxide of lead which would adhere well and be of sufficient thickness, without attacking the plate too strongly, it would be necessary to realize certain conditions during formation. Generally this is accomplished in the following manner: the plates to be formed are fixed in vessels with counter electrodes of lead. The vessels are filled with an electrolyte, containing a certain fixed quantity of Sulphuric acid and ac- celeeating substances, a charge is then made, the plates to be formed being taken as the anodes, the intensity and duration of charge being deter- mined. - The factors, then, which have an influence upon the thickness of the layer of peroxide, and hence upon the capacity are: the strength of the sulphuric acid, the strength of the accelerating substance, the quantity of the 789 electrolyte, the strength of current, the quantity of electricity, and the temperature. This last factor is not less important when use is made of oxidising salts (nitrates, chlorates etc.,) as accelerating substances. Here for instance, are some figures obtained with an electrolyte to which sodium nitrate had been added: Temperature of forming in degrees Surface capacity of the formed plate in ampère Centigrade. hours per square decimetre of active surface. 40 O-274 27 O'695 13 O'905 In these experiments all the other conditions, excepting the tempera- ture were exactly the same. As may be seen, the lower temperatures allow obtaining a thicker layer of peroxide of lead, and hence a higher capacity'). In order to explain the part played by temperature, it will be neces- sary first to study, by means of temperature coefficients, how the proportion of the NO, anions SO, anions which are given up at the anode, varies when the temperature is varied. But this influence did not appear of much impor- tance, and rather pointed to advantages for high temperatures. It is, above all, in the increase of the coefficient of diffusion as a function of the temperature, that this factor appears to have most influence. When, in fact, oxidising agents, such as nitrates and chlorates, are found to be present; reduction takes place during forming, of these at the cathode, and the electrolyte loses more and more of these substances. The following are some figures obtained with sodium nitrate, indi- cating this decrease in concentration, expressed in sodium nitrate, the NOs ions serving to depolarize the cathode, being liberated in the form of nitrogen dioxide. Proportion in grammes of N A N O's per litre At commencement of forming 7:6 After 158 hours 1.5 to 2 > 28 Y. O'9 » 40 X) O-3 X 52 X O'3 » 71 X O'15 » 76 Y). O'10 But it is well known that diffusion takes place much more readily when the temperature is high. It is, then, at the lower temperatures that the diffusion of the nitric acid at the cathode, and its reduction to nitrogen i) G. Just, P. Askenasy and B, Mitrofanoff (Zeitschrift für Elektrochemie Chapter XV. 15th November 1909, page 872) have also verified this fact by experiment. 790 .*** dioxide, take place most slowly, which is as much as to say that, under these conditions the NOs ions act for the longest time at the anode, and cause the deepest forming, w In the electrochemical forming of plates of large surface a cold tem- perature may therefore be employed with advantage in order to form the plates more deeply; also to keep the temperature of forming constant in summer and winter, and hence to obtain the same results in all cases. This last point is of great importance to the manufacturer of accumulators, because, if the conditions are regulated in summer, there is a risk of the plates being formed too much in winter, and in consequence lasting for a shorter period. Vice versa, if the conditions are such that normal forming is obtained in winter, in summer plates would be obtained insufficiently formed, and hence not having their full capacity. It is for these reasons that certain manufacturers cool their forming baths to a constant temperature in the neighbourhood of 10°C, or even a little lower. To our knowledge it is La Société pour le travail electrique des Métaux (The Electric Metal Working Company) which first applied these principles. It possessed in fact, in 1898 an installation for forming at a low temperature. The forming vessels, filled with an electrolyte of nitrate, were placed in wooden cases, through which circulated a cold liquid, provided by an ammonia machine. The temperature of the forming baths was thus kept constant at 10° C. Very regular forming was thus obtained, without cating in too deeply, the grids having a large capacity. 791 On the lnfluence of Recent Improvements in Heat and Re- frigerating Machinery, and of the Progress Made in the Trans- mission of Energy, Upon the Cost of the Calorie and Frigorie Respectively, and Hence on the Advent of a System of Con- centration of Solutions by Freezing, and by Condensation, in a Vacuum at a Low Temperature. By Dr. Eudo Monti, Chemist of Turin, late director of the Laboratory of Experimental Research -- of the Krios Company, Turin. In the year 1902 I made, in the laboratories of the Italian Industrial Museum and in the factories of the Italian Artificial Ice Company, numerous experiments on the concentration of solutions by freezing, the results of which I communicated to the fifth Congress of Applied Chemistry, which met in Berlin in June 1903 (see the proceedings of the congress Section X, Volume IV, Page 687). From the results obtained, a group of Italian capitalists, among whom I ought to mention Messrs. Ludovico Scarfiotti, Giovanni Agnelli, Laureato Fiotto, the Italian Distilleries, and the firm François Cinzano, have put at my disposal the sum of one hundred thousand francs for industrial ex- periments on the concentration of different solutions, and for the study of the properties of the products thus obtained. As these experiments have shown the possibility, and the advantage of the concentration at a low temperature of solutions in general, and of wine and must in particular, The Krios Applied Refrigeration Company was floated in March 1906 (with a capital of one million four hundred thousand francs), and proposing the concentration in large quantities of wine and must, as well as the continuation of investigations upon the influence of cold upon the maturing of wine, and in general upon the organic and physical pro- perties of different products of industrial importance (extracts of meat, peptones, perfumes, ferments, pigments etc.) With this object the Krios Company has built two factories at Pescara and Castellamare Adriatico, with a capacity for treating 50,000 hectolitres of wine or must per annum, and has set up a laboratory of experimental research at Turin. 792 I made a resumé of part of the work done in the Krios Laboratory up to the end of 1908, dealing with products of the vine, in a report accompanied by over 200 samples of the various products, which the judges of the exhibition of bye products of the vine have referred to in their general report (see *The journal of the society of Italian Agriculturalists.<, Rome, May 31 * 1909, No. 10. from page 532, also pages 598 to 612). On the other work I have published several data in the Proceedings of the Sixth Congress of Applied Chemistry (Rome 1906) Volume IV from page 143, also Volume V from page 666, and in a report which I made to the Second International Congress of the Sugar fermenting industries, which met in Paris from the 6th to the 10th of April 1908 (see the proceedings of this congress, part 4 ſwine making] from page 122). I had intended to make a detailed report to the congress on the researches made in the Krios labo- ratory of which I have been made manager. * Unfortunately the reports which I spoke of in No. 6 of the journal of the International Association of Refrigeration (July 1910 page 110) were not written at the time, and I am indebted to the General Commissioner and the President of the fourth section for their kindness in allowing me to resumé my report at the present meeting which is being held, while the sections are assembled to draw up resolutions to be proposed before the general meeting. However, as I am aware of the unsuitability of entering at this time upon a long discussion on two subjects so important in the progress of the refrigerating industry, I shall delegate the detailed discussion on the work done and the results obtained to the international commission which you have just formed to further the application of cold in the chemical industry, and I will confine myself to submitting to the congress a French translation of the note appended to the general report of the judges at the exhibition of bye products of the vine (Rome 1909) and two prospectuses giving a resumé of the results obtained at the Pescara factory during the nine months work from the first of December 1907 to the thirty first of August 1908, which shows how it is that the loss of alcohol ... and sugar, which hitherto has formed the greatest obstacle to the com- mercial application of concentration by refrigeration, has been reduced to practically negligible proportions. I should add, however, that, to obtain these results, it has been neces- sary to soften the non conducting layer of ice adherring to the coils, by means of circulating a current of brine at the ordinary temperature, which resulted in melting part of the ice separated out. Experience has proved that 62 kilogrammes of ice must be formed per 100 kilogrammes of solution to effectively separate 55%, and that the number of calories absorbed per 100 kilogrammes of ice separated out varies, according to the time of the year, from 100 to 120 calories, and in summer the average is 112 colories, absorbed by the brine of an average temperature of 12 degrees below zero centigrade. 793 I have also observed in practice that each gramme of alcohol dis- solved in 100 grammes of water lowers the freezing point by 0.4° C; each gramme of grape sugar lowers it by 0-11° C; each gramme of unsweetened extract by 0.15° C, also that the capacity of the refrigerating machinery diminishes almost proportionately as the weight of gas used by the Com- pressor in a given time diminishes. Also that the displacement of the con- centrated solution with ice crystals becomes slower and more difficult as the density and viscosity of the concentrated solution increase. Hence it is not advisable to proceed any further with the concentration of sugar solutions by freezing, when the proportion reaches 100 grammes of Sugar in 100 grammes of water. In practice I have observed that it is very easy and far more economical to get rid of the water in a vacuum, using the ice extracted to cool the condensed water down to zero centigrade. The same result could be obtained by making use of Dr. Gürber's apparatus, but, as it is more costly in use than the concentration in a vacuum at a low temperature, its use is only advisable in the case of very perishable products. Under the conditions described, evaporation should be carried out at a temperature of about 10° C, using the condenser water of the refri- gerating machinery to warm it up. As in this case the rendering of the apparatus is low, it would possibly be better to make use of water at about 40° such as comes from a steam condenser, or the water jacket of a gas engine; the temperature of evaporation then rises to about 25°C; thus fruit juices, crystallized must and grape syrup of excellent flavour are obtained. A series of experiments made at Pescara with a set of three concen- trators of a capacity of 10 hectolitres each, fitted with pipe coils, and working by the direct expansion of carbonic acid supplied by a small Hall compressor having a capacity of 3500 frigories, and working alternately as an evaporator and as a supplementary condenser (Nachkühler), have proved that, power used and the amount of concentration obtained (concentrated red filtrate) remaining the same, the time taken by the operation diminished from 20 to 14 hours only when the ice on the Nachkühler which had been separated from the wine was slowly melted by sprinkling with the refrigerating water at 15° C. Hence the useful work done by the refrigerating machinery is increased by 35°lo. Some experiments made at the Alba Ice factory go to prove that, by properly regulating the piston speed of a carbonic acid refrigerating machine in such a way as to have the amount of gas drawn in and compressed within a given time practically constant, the x output.« of the machine is kept constant although the temperature of the brine is lowered from 5 to 14 degrees below zero centigrade. After the publication of my report Mr. Banfield, Technical Director to the Linde Co. at Wiesbaden, wrote a letter to the Italian Artificial Ice Co. saying that the time when his firm made machines giving an * outputs of 2,000 frigories per horsepower hour is long past and that the present > outputs of large ammonia compressors is from 3800 to 9000 frigories per 794 horsepower hour and even more. In fact he pointed out that, at the con- ference which has recently met a Glasgow under the auspices of the Union of Marine Engineers and Constructors, a large double compressor absorbing two million calories per hour with brine at –10% used for drying the air for blast furnaces only required 750 horsepower, including the power required to drive the pumps and ventilators. I have also been informed that some large carbonic acid gas compressors installed at Băle by the Escher Wyss Company give an "outputs of more than 3000 frigories, and that several plants by the same firm give an outpout of hardly less. It is only fair to remark, however, that in many plants only 50 to 75 per cent of the power developed by the engines is transmitted to the compressor. In spite of the improvements introduced the efficiency of a good furnace does not exceed 65%, and about 1200 grammes of steam are required to evaporate one kilogramme of water in a single effect apparatus. The evaporation of the same quantity of water in a good quadruple effect apparatus only requires 400 grammes of steam. It is, however, evident that concentration by freezing involves a consumption of energy or fuel which is usually lower than that required for evaporation, even with a quadruple effect apparatus, and the only serious obstacle which lies in the way of the application of concentration by means of cold to the chemical industry on a large scale, the somewhat high price of the concentrating and refrigerating apparatus, has been eliminated to some extent by recent improvements, which, while considerably increasing the capacity, have greatly reduced the price of the apparatus. Nevertheless I would request the Congress to submit the following resolution for the examination of the commissión which has just been formed for the application of refrigeration to the chemical industries: Whereas the progress recently realized in the production and distribution of energy allows of obtaining power at a price varying from 80 to 280 francs per horse power year, or an average of about 200 francs; Whereas, moreover, large refrigerating plants have recently been con- structed which consume less than one horsepower for the absorption of 2,500 calories with brine at ten degrees below zero, while even in the best constructed furnaces the efficiency does not exceed 65"lo; and under these conditions the absorption of a calorie sometimes costs less, and never much more than its production by the combustion of oil. Whereas also in some large installations, for the concentration of solutions by freezing, 112 frigories at most are required in practice to make one kilogramme of ice from Solution, and the application of new methods of displacement of soluble substances by the use of crystals of ice has reduced the losses of these soluble substances to a practically negligible quantity, and whereas, finally, under these conditions, concentration by freezing, completed by evaporation at a low temperature, is far more economical than concentration by boiling, even by multiple effect plants, the Congress passes the following: 795 Resolution. That refrigeration associations should call public attention to the facts mentioned above, and that they should encourage the study of the application on a large scale of concentration of solutions at a low temperature to the great industry of extract making. w - 796 Changes in the Physical, Chemical and Organic Properties of Vegetable Extracts, Particularly Wine, Must and Fruit Juices, Caused by Permeating them with Air at a Low Temperature, and the Subsequent Release at Summer Temperature of the Air Thus Dissolved, By Dr. Eudo Monti, Chemist of Turin, late Director of the Laboratory of Experimental Research of the Krios Company, Turin. It has long been known, especially by the wine dressers of Champagne and Burgundy, that the action of cold assists the clarification and maturing of wine. The majority of wine growers, however, think that maturing is in- dependent of the action of the air (recently Dr. Charles in his article on the action of cold on wines, noted that air, acting at a low temperature upon wine is almost as energetic as at a higher temperature). Many wine experts think that cold produces clarification in must and wines only because the tartar and dregs are less soluble at a low tempertaure, and hence they imagine that it would be enough to cool the wine to a given temperature for some minutes, or a few hours, to assure permanent clearness at a temperature equal to or above the temperature to which the wine or liqueur has been cooled. But taking some wine which had been kept for several weeks in a chamber cooled down to —5° C., and which had been filtered in the air of this chamber, I was greatly astonished to find that, on placing it in a chamber at the ordinary temperature (August 15* 1904), large amounts of tartar and sediment were deposited at the bottom of the . bottles; and also to observe that the wine which had been aerated and filtered in the cold room seemed to be fully matured, whereas in the case of the same wine which had been kept in stoppered bottles, placed in a cold room and poured out protected from air no maturing was observed even in the case of a bottle sealed by a blow pipe, and which had been kept for six months in a room cooled to below 4° C. Evidently Pasteur's classic experiment gives the same result at a cold temperature as it does at the ordinary temperature. Therefore it is air and not cold which causes wine to mature, and it is air and not merely cold which causes the formation of a deposit. Continuing these experiments, and working not on small samples, but on casks, and then on large vats full of must and wine, I have observed that wine and must clarified by cold, in the absence of air, always precipitate afresh when air is allowed to come into contact with them, and that the phenomena of maturing do not take place 797 when wine is cooled down wich contains no oxygen dissolved by contact with air. I then repeated the experiment, blowing sterilised air through wine which was cooled down almost to Saturation, and then taken to a room at the ordinary temperature which, in summer, is about 28° C., and observed that the air was given up in the form of very small bubbles, and that the formation of these bubbles was accompanied by a very considerable maturing effect in the wine, and almost always by the formation of fresh sediment. I have also observed that on submitting must and fruit juices to the same treatment, after they had been concentrated by freezing SO as to contain 50 to 60 Kg. extract, also malt sterilized after filtration or decantation at a temperature not exceeding 55°C., that the said musts, made from highly flavoured grapes such as the nebiols, the muscat, the barbaresco, the friesa, caquired teh same flavour which characterizes the sweet wines made from dried grapes highly seasoned with botrittis cinaerea, such as that of Sauterne and Johannesberg. On placing olive oil in a flask filled with wine thus treated, I noted that this oil became gummy in a few weeks, and hence inferred the presence of ozone in the gas given off by the wines. I should say, however, that, on treating the same wines with air strongly ozonized by an electric discharge, the taste acquired by the wine does not in the least resemble that acquired by maturing naturally. And I have even observed the formation of acetic acid, while the taste of wine Saturated with air at a low temperature and kept for some time at ordinary summer temperature might be taken for old wine. On repeating the experiment by Saturating the wine with Oxygen obtained by electrolysis ad compressed in the Tivoli factories, I have noticed the same changes in the taste which I observed on saturating it with ozonized air, but carrying the experiment out again, with non ozonized oxygen obtained by the fractional distillation of liquid air on Professor Linde's system, I ob- served no differenc between this and the wine which was saturated with atmospheric air, which might easily have been foreseen because the presence of nitrogen does not diminish the solubility of oxygen in wine. From the foregoing I have drawn the following conclusions: 1. That cooling only makes must and wine perfectly clear when they contain no materials which give insoluble products on oxydation. 2. That this effect is obtained much more rapidly by oxydation at a low temperature than it is by agitation with air at the ordinary temperature. 3. That by saturating refrigerated wine once, twice or thrice with air (possibly sterilized), and by allowing this to escape slowly at an ordinary summer temperature, wine is obtained which, in most cases, is in every way similar to that which has been matured naturally. 4. That by saturating concentrated must with air and then keeping it for a long time at a low temperature, the ferments mentioned can be completely separated, and that, under these conditions, it is enough to heat it up to about 55° C. to thoroughly sterilize it without separating its lecithin, 98 nuclin, albumose and many other substances of a very high alimentary and therepeutic value, which are separated completely if the must is heated up to 75° or 80° C., as is done in the Müller and Thurgau processes. º In fact, as Berthelot has stated, must and fruit juices, as well as the wine obtained therefrom, contain a much larger proportion of organic phos- phates than is indicated by the analysis of their solid residues, and in some cases the amount of phosphoric acid found by the Berthelot methods has been 6 times as large as that found in the solid residue. I need not emphasize the importance of a process wich allows of keeping in concentrated products, which have an excellent flavour and which change with difficulty, all the constituents to which the ripe fruits owe their beneficial action on enfeebled organs. In October 1905 I patented the maturing process which I have just described in France and other countries, but on endeavouring to obtain patents in Germany and America, objections were made, on the grounds that my statements were contrary to the accepted laws of chemistry, because it was not probable that air would act more energetically upon wine under the influence of cold than under that of heat, and that fresh tartar and dregs would be formed at a temperature above that to which the wine or must had been previously submitted; and the same objection was made by the appeal division of the German Imperial Patent Office. Being quite certain of the reality of the phenomena which I had per- sonally observed, I accepted the proposition that I should entrust the verifi- cation of the facts mentioned to the Royal Institute of Geisenheim, as well as a comparison between the effects of oxydation at a low temperature with those at the ordinary Summer temperature, or at the temperature at which Pasteurization is carried out. I now have the pleasure of presenting the report of the Institute to the Congress, as well as the decision of the appeal section, which declares that as the report of the Geisenheim Institute has dispelled all doubt as to the efficacy of my process, there is no longer any obstacle to their granting me the patent, the text of which I will place before the Congress as well as the claims drawn up in conjunction with Mr. Rothembach, advocate of the appeal division. - -- The researches directed by Mr. Van der Heide were carried out on 22 diffe- rent kinds of Rhine and Moselle wines as well as on Italian, French and Spanish wines, French and German brandies, and partially fermented currant juice. The results greatly surpassed my expectations, because although the judges at the Rome and Alba exhibitions decided that Barolo, Marsala and other Italian wines, matured by being saturated by air at a temperature of –5° C. and being made to give it up at a temperature of 28°C., had the same taste as old wine, and I had only worked with such delicately flavoured wines as Rhine wine, the experts refused to believe that these wines were not old. Mr. Van der Heide has summed up the results of the researches in a synoptic table (of which I give some extracts). 799 The observations set forth in this table confirm the extremely important fact that wines which have been cooled and filtered at a low temperature, again become cloudy and form fresh sediment when they are kept for some time at the ordinary summer temperature; the same observations also confirm the fact that the maturing of brandy, requires several saturations while cold, each followed by the air being given up below the ordinary summer tem- perature, that the presence of wood extract is essential to the formation of the complex ethers, aldehydes and acetones which characterize old brandies; and they have also confirmed the fact that saturation with air at the ordinary temperature does not cause wines to mature appreciably, while it detracts from the flavour of fine and highly flavoured wines such as Johannes- berg, which served for the experiments. The experiments carried out at Geisenheim have also confirmed the fact that all fruit juices are matured by this process, as well as grape juice. These experiments were carried out with the support of and under the control of the Minister of Agriculture, the French Refrigeration Association, and the general syndicate of the Refrigerating Industry, under the able direction of M. Mathieu, upon a number of fine French wines and brandies as well as upon ordinary red and white wines of good quality and largely consumed, and I hope to present before a subsequent congress the results of fresh experiments, uncompleted at present, upon the precipitation and clarification of extracts made from the juice of the sugar beet, and a number of vegetable extracts, which I have presented to the exhibition of bye products of the vine, at Rome, also the results of researches upon the composition of must, concentrated and oxydised by cold, and its effects on the human organism. Chemical Table for the concentration of 13.478 hectolitres of wine and must carried out at the Kriosa factory at Pescara, Italy, by freezing, and the systematic displacement of the soluble substances by the interposition of crystals of ice (Monti's patent). Quantities and analysis of mixtures undergoing concentration. Alcohol 9/o Alcohol in litres Extract "lo Extract in kg Hectolitres 7930 × 8.89 = 70497.70 Hectolitres 7930 × 6.46 = 51227.80 1220)× 6.20 = 756400 1220 × 6.49 = 7917.8O 610 × 6.51 = 3971.10 1220 X 6.19 = 7551.80 1220)× 6.15 = 7503,00 58 × 3.95 = 229.10 85964.60 Extract recovered in the concentrated product . . 81882.10 4082.50 Weight of tartar separated 2020.12 Extract remaining in the ice 2062.38 1220×9.23 = 11260.60 1220× 8.98 = 10955,60 610 × 9.32 = 5685.20 1220 × 9.23 = 11260.60 1220 × 9.06 = 11253.20 58 × 3.64 = 211.12 13478 120924.02 Alcohol recovered in the concentrated product . . 117423.71 Alcohol evaporated and remaining in the ice . . 3500.31 800 Quantities and Analysis of Extract obtained. Alcohol "ſo Alcohol litres * Extract "ſo Extract kg Hectol. 1462.50 × 15.85 = 23180.60 | Hectol. 1462.5 × 11.08 = 1620400 1452.50 × 17.84 = 25912.60 1452.5 × 11.39 = 16542.90 1457.50 × 16.24 = 53669.80 - 1457.5 × 12.05 = 18218.70 910,00X 17.54 = 15961.40 910.0 × 12.26 = 11156.60 1452.50X 17.04 = 24750.60 1452.5 × 12.50 = 18156.20 200.00 × 17.32 = 346451 200.0 × 6.45 = 1290.50 6000 X 8.07 = 484.20 60.0 × 5.22 = 313.20 117423.71 81882.10 The loss in 100 litres of alcohol is 2.89 litres, in one hectolitre of the mixture concentrated it is 0.267 litres. The loss in extract in 100 kilogrammes is 2.39 kilogrammes, in 100 litres of the mixture it is 0.153 litres.) The analyses were made on the concentrated extract ready for sale. The loss also includes the waste caused by drawing off and filtering. From the 1st of March to the 1st of August 1908 there were concentrated in the factory of the Krios Company at Pescara, 22,864.56 hectolitres of a mixture of Sweet filtrate and dry wine containing 62.5 grams of dry extract per litre and 72 centilitres of alcohol per litre. Thus these wines contained 73,491 kilogrammes of extract and 92,523 litres of alcohol. - From this 527,416 litres of concentrated filtrate were obtained and clarified by cold, from which 924.5 kilogrammes of practically dry tartar were separated. This essence had an average composition of 136.5 grammes of extract, and 17.5 centilitres of alcohol per litre. It therefore contained 72,031 kilogrammes of extract and 91,850 litres of alcohol. Hence the loss was 144,006 kilogrammes of extract and 1674 litres of alcohol, that is to say 1.96% extract and 1.81% alcohol. The loss in 1 hectolitre of the mixture concentrated was 0.22 litres of alcohol and 1.80 grammes of Sugar and extract. - As it is impossible to examine or taste the numerous samples which I have brought now that the sections are assembled to discuss the conclusions and resolutions to be put before the general meeting ; or to examine the numerous reports on the results of experiments in concentration, clarification and oxydation of a number of other solutions such as beetroot juice, coffee, tea, perfumes and vegetable extracts in general; also by concentration, under the influence of cold, of substances insoluble in alcohol, gelatine and albumen contained in meat extract; the influence of temperature upon the ferments 1) The actual loss is only 1.81 per cent of alcohol and 1.96 per cent of extract, or 0.22 litres alcohol and 0.18 of extract per hectolitre of wine concentrated. 801. ...' etc.; also reports on the chemical composition of the products derived at … high and low temperatures from natural must, and must concentrated by cold and by heat, and especially the proportion of acetic acid which is formed by fermenting must at different temperatures in the absence of the mycoderma aceti. Lastly to refer to the results of a number of other researches which I have been unable to complete and which, as they are in skilled and experienced hands, will without doubt add new and important chapters to physical chemistry and the different branches of applied chemistry. I propose, Sir, to communicate to the International Commission that you have drawn up the fellowing resolution. Whereas the saturation of wine, must, fruit juices and vegetable extracts in general with air at a temperature as near as possible to their freezing point, and the giving up of this air at the ordinary temperature, has the effect of clarifying, improving and maturing them and of intensifying their flavour. And whereas by the combination of this process with concentration at a low temperature it is possible to condense into products which may be easily stored and transported the flavour and very perishable components to which grapes and ripe fruit owe their alimentary and therapeutic value the Congress passes the following Resolution. *That Refrigeration Associations study and encourage the application of Oxydation at a low temperature to the maturing of wines and to the refining, clarification and improvement of must, juices and extracts, calling the attention of medical associations to the properties of the products thus prepared and their alimentary and therapeutical applications. Report on a Liquid Oxygen Life-saving Appliance and on Apparatus for the Production of Liquid Oxygen. By M. Georges Claude, Laureate of the Institute. Principle. That liquid air has already been proposed for and applied to life Saving apparatuses, is not surprising, as its extreme density gives it inestimable advantages for this purpose. Because of the inconvenient nature of the apparatus required and especially, because of the difficulty of having large quantities of this powerful liquid ready for use at any moment, the use of these apparatuses has not become general. - The life saving apparatus made by the 'l'Air Liquides Company the design of which we owe Dr. Stassen, Manager of the Esperance Dispensary at Montegnée-lez-Liège, is based upon the phenomenon of the spontaneous evaporation of liquid oxygen by heat. The life saver is furnished with purc oxygen, and the point should be specially noted, that a popular belief attri- butes supernatural properties to oxygen, which it does not possess. The use of liquid oxygen instead of liquid air avoids the disadvantage of supplying the life saver with air whose composition varies continually, and for the same reason, it avoids the necessity of regulating evaporation, as in the case of liquid air, so as to fournish too much oxygen at first, when the air is enriched therewith. An idea of the importance of these facts may be obtained by taking into account that the amount of liquid air proposed to be carried is no less than 5 litres, while by the method mentioned above the charges of liquid oxygen do not exceed 1.5 litres. It is evident that this fact alone lessens the objections which have been made to this kind of apparatus. De Scription of the app a r a tu S. In the apparatus made by the »l'Air Liquide & Company, the oxygen is contained in a metal reservoir. A (fig. 1), and protected by a heatproof material which surrounds it, so that the user can assume the unusual positions which are often forced upon him by circumstances. This reservoir is enclosed in an insulator C, also heatproof, which is made of mineral wool. This insulator is placed in a second metal vessel B, which is very strongly made, as are the other parts of the apparatus, so as to resist, without injury, the violent shocks to 803 which it is often subjected while in use; this is an important condition which the new apparatus seems to fulfil in a more satisfactory way than other existing apparatuses. - By the above means, an insulating effect is obtained which limits the amount of heat from outside, and which prolongs evaporation over any period desired, say, two hours to two and a half hours. . . . . . . - A very simple calculation shows the abundance of the supply which is thus assured to the life saver. A man who is working very hard requires 120 litres of oxygen per hour. Now, the litre and a half of liquid oxygen contained in the apparatus, evaporates in two hours into 1:200 litres of gaseous oxygen, at a rate of 600 litres per hour. This is five times as much as is required by the user. * - ... • * * * * * * : * * * - - * . . g§- š- *~ t flººr; hºx- 2-- *|† JS ~T- * * ~ * * -- *| off- .* * * ~s ~~~~ S-r *A. ‘o º - - £2-- . ... --> ... ---- * / . * *. 2-2 o H_ºt- * 2 / ~~ *… . . . . . .” - K. S 2 - 2 of 2. ~ *- : * - 2 3 • -- 2 : J " * - 22 -, o –- . ~ ~ J ſ--> *-* /*-2 o!--ſº *...e -* < 2/ -* . . , --. 2- vº 21, 2- - ** -- . ~ ~~~~ * .*__. . * rº- ...— ... -- 3 zº.º. .* -jºº" es 4 _** ** * • - "T"--, - . . .” ** -- - " " " " - - - - - - - - - - - - - "" " --- *** * * * * * * * = . . . . * * * * * *** * ~ * * Åservoir 2 oxyséve ſizvios Farez; o'aajaa’re ſecſeiswr . /sowawr. AAims as vºws **w cazurrºove eavy oxygena gazezar ſºcieżar 72&f 25 ørazzazzazaar Aſasque . Soº'eeee of ozcaazcz LEssayas | Fig. 1. Sketch of liquid oxygen apparatus for life saving. But this abundant supply is not extravagant as one might think; in fact a great advantage is derived from it. In an appliance which works entirely on present methods, and which is based upon the use of compressed oxygen, only a very small amount of the gas can be carried, because of the excessive weight of the bottles needed to hold it, and it must be used to the last particle. Care must be taken not to reject the products of respiration which still contain large quantities of oxygen, and they are made to pass through cartridges of special substances, which ab- sorb water and carbon dioxide, the oxygen used up being replaced with new. Now these complicated and costly regenerators and encumbrances are unknown in the apparatus described. Here, as we shall see, it is, sufficient to get rid of the most impoverished gas, that which comes at the end of 51% each exhalation; so that that part of the exhaled gas, which is not got rid of, still containing large quantities of oxygen, can be flooded with a large amount of fresh oxygen, and used again without inconvenience. The vaporised oxygen does not come directly to the mask; evapora- tion being a continuous and relatively slow process, inhalation being, on the contrary, an almost instantaneous act requiring a considerable volume of oxygen, an intermediate process is required. For this purpose the Fig. 2. Life saver provided with the ºl'Air Liquideº Company's Apparatus. Exhibited at Brussels at the Stand of the Ministry of Public Works. - | vaporized oxygen is first sent to a rubber bag D, having a capacity of 5 to 6 litres, enclosed in a metallic case E for resisting pressure. From thence it comes to the mask M by means of the tube T which is of the required cross-section. The mask is affixed to the face, in the apparatus as at present arranged, by a device which is quite air-tight, no matter - what the shape of the face. A small valve S, in the tube where it enters the mouth of the user, closes automatically on inhalation; on exhalation, however, it allows the 805 expelled air to escape, while before the end of the exhalation the rubber bag is filled with the first of the exhaled air, and at the same time with the oxygen vaporized between two successive respirations. It is, therefore, the most vitiated gas which is automatically rejected, and it is because of this that the proportion of exhaled gas in the bag is not such as to be harmful, in spite of the absence of regenerators and the use of a very small amount of liquid oxygen. The extreme simplicity of this apparatus is obvious, and it can be seen that all the causes of irregular and uncertain operation in present day apparatuses, such as gauges, valves, injectors, regenerators etc., are reduced to a minimum. Outside heat is all that is required to vaporize the liquid oxygen, and it is always available. The following figures will show that the efficiency of the new appara- tus is beyond comparison. Compressed oxygen appliances, which as we have said are undoubtedly in favour at present, carry 300 litres of oxygen for a weight of 15 kilo- grammes. The apparatus described, for a weight of 8 kilogrammes, or half as much, carries 1200 litres of oxygen or four times as much. It allows of a man remaining for two hours in an unbreathable atmosphere. When it is remembered what unlikely positions the rescuers may have to assume in narrow galleries, where they have to crawl along, and Sometimes to climb steep slopes, and that they accomplish all this at a temperature which may reach 35 to 40°, as at the Belgian State Stations, where tests have been commenced with the appliance made by the ºl’Air Liquide & Company, we can appreciate the advantage of reducing the weight which the rescuer must carry from 15 to 8 kilogrammes, and of making the appliance very strong, Simple and unlikely to catch against obstacles. Lastly the rescuer is furnished with a gas of agreeable freshness, and which is conveyed to him by means of a mask, avoiding the unpleasantness of bathing the face in the warm damp products of respiration, an incon- venience which might almost cause serious accidents with certain present day appliances. Compared with the liquid air appliances already mentioned, the above apparatus weighs 8 kilogrammes loaded, instead of 11 and only requires 1:5 litres of liquid instead of 5. Now, a large quantity of liquid is not only inconvenient from the point of view of weight and cost but it produces an enormous amount of cold by its evaporation which it is difficult to militate against. The production of liquid oxygen. It might be thought from the above that the appliance described is an ideal one. We must however yet provide liquid oxygen ready to hand, and this is a delicate point. Objections which have been raised against this kind of apparatus apply more to the liquid used than to the appliances themselves, as this volatile 806 liquid can only be kept in the excellent but fragile vessels of d'Arsonval and Dewar. With the enormous quantities of liquid air required by the appliances of that type, with the complication and limited output of liquid air machinery, the trouble is always to have in reserve the quantity of liquid air necessary in case of accidents, which would necessitate a veritable store-house of vessels always being filled. In a very exhaustive pamphlet published by Messrs. Stassart & Bolle, of the Belgian State Mine Service, Fig. 3. Another view of the ol'Air Liquideº company's appliance. - this reserve is calculated to be 420 litres of liquid air per station, in 80 d'Arsonval receptacles. This would obviously be impracticable, and it follows that the reception accorded to these arrangements has often been – cold! Undoubtedly reducing the charge of liquid necessary greatly minimizes this objection; we have, however, often thought how advantageous it would be if improvements in the method of manufacturing liquid oxygen were devised. The ordinary liquefying apparatuses as a matter of fact only produce liquid air, which is only converted into oxygen after a considerable waste. The rectifying apparatuses for separating the oxygen and nitrogen, moreover, require a long time, about four or five hours to perform their functions; and if their production of gaseous oxygen is great, that of liquid oxygen, which completely upsets the frigorific balance of the plant, is rather small. A plant intended for life saving appliances should produce liquid oxygen almost immediately and abundantly, when required. After many attempts, M. G. Claude and M. Le Rouge have discovered a very simple solution. This solution is to take the compressed oxygen as - Fig. 4. Back view of the ºl'Air Liquideº Company's Apparatus. supplied commercially in cylinders, and to liquefy it by compression aided by air expanded by external work (see figure 5). Since this gas is specially suitable for liquefaction, its critical temperature being only –118° C. as against –140° C. for air, the process is very short, and liquefaction begins to take place after about 20 minutes. Moreover, because of this high criti- cal temperature, the thermodynamic yield of expansion is excellent, and the production of liquid oxygen reaches twelve litres for 20 horsepower, nothwithstanding the small size of the plant. 808 Lastly, the plant is reduced down to a simple liquefaction machine, and is much less complicated, and less costly, than the apparatus required for separating the oxygen and nitrogen. º But though this plant can furnish liquid oxygen rapidly and abun- dantly whenever required, it would be too expensive, in view of the price of oxygen, to use it in this way for the periodical practices in life saving, which are necessary in this, as in other cases, to keep the staff, and appa- ratus efficient. - It will be sufficient for these practices, to make liquid air, and to trans- form it into oxygen by suitable vaporization at a rate of 3 or 4 litres per sº | i | i r Fig. 5. Diagram of plant for producing liquid oxygen. A. Compressor; B. Dryer; C. Temperature interchanger; D. Vacuum Pump; E. Liquefier, provided with oxygen from the battery of cylinders F. hour. It is also in this way that the 5 or 6 silver bulbs, which form a small reserve, are filled once or twice in a week, to provide for immediate need in case of accident. t This is evidently a long way off from having eighty receptacles full all the time. A better solution, from an economical point of view, would be to thus equip a central station serving several mines, as are often found within a radius of a few kilometres. In this station, four squads of 4 or 5 rescuers being assigned to each mine, according to the Belgian regulations, the prac- tices would be so frequent, that a litre of liquid oxygen would come to 809 about 1:2 francs, storage included, and the price of each practice would come to 3 francs per man. Thus, we arrive at the conclusion that, in the case of a central station, this system would not only provide the most per- fect solution of the question, which seems beyond doubt, but the most eco- nomical one, other systems involving outlays of 3.5 to 12 francs per practice. (See the work of Messrs. Stassart and Bolle, Report on Belgian Mines for 1909.) * The initial outlay itself, about 25,000 francs for the liquid air plant, would be partly balanced, at least to an amount of 10,000 francs, by the greatly reduced cost of the life Saving appliances. For a single establishment the price of the liquefying machinery might be reduced to twenty thousand francs. S to ring and Carriage of liquid oxygen. There is one more objection made against liquid oxygen life Saving apparatuses and which M. G. Claude has endeavoured to eliminate. The apparatus working on this system always begins to act the moment it is charged, and as a considerable time may elapse before the user gets to the locality where the appliance begins to be useful to him, the useful duration of the charge might be thus reduced to almost nothing. It is, however, out of the question to carry d'Arsonval-Dewar receptacles into the pit, they are far too fragile. The objection seems to be a serious one. Considering with the abundance of liquid oxygen which can be pro- vided by our plants in case of accident, the liquid can be stored in simple iron cylinders, insulated with mineral wool. The experiment has been made, and it has been shown that the evaporation from a 20 litre receptacle does not exceed 0.7 litres per hour. This is negligible, so that the oxygen can be taken to the bottom without difficulty, where the appliance can be recharged by means of simple ladles. Thus the last objection against the use of this apparatus, which seems destined to revolutionise present methods of life saving, is disposed of, just when they are becoming compulsory in the different European nations. 810. Report on the Recovery of the Vapours of Volatile Liquids by Refrigeration. By M. Georges Claude, Professor, Paris. As you are aware, gentlemen, the exigencies of manufacture in Several important industries, such as the artificial silk from Chardonnet, Smokeless powder, celluloid, etc., necessitate the loss of the costly liquids used, especially alcohol and ether, under the form of vapour diluted in large quantities of air. -- Numerous efforts have been made, to regain these valuable vapours and the patented inventions for this purpose can be counted in hundreds. And this is not to be wondered at, when it is known that the losses suffered by the industries amount to several tens of millions francs yearly. I would cite the case of a single industry where the loss of vapours, in spite of an already important process of recovery, exceeds the surprising figure of two million francs a year. We are dealing, therefore with a question of great importance. The processes of recovery which are now beginning to be employed. are generally derived from the sphere of chemistry. Absorption of vapours by sulphuric acid in towers, similar to those of Gay Lussac, distillation, and concentration of the sulphuric acid, are the usual characteristics of these processes. At first sight the scheme of these operations is very attrac- tive. In reality, however, these processes are not very economical, and involve disadvantages of all kinds; and moreover they are incomplete by reason of the small proportion of the vapours treated, which naturally constitutes the great difficulty of the whole matter. Is it also to be considered a good result when at the present time 50 to 60°/, of the vapours are recovered? A great deal of trouble and expense is involved to produce so small a result, and we can understand that many important works prefer simply to lose the vapours. I have often referred to this question, and I believe that the solution at which I have arrived, presents advantages of simplicity and efficiency which have not hitherto been attained. I have already had occasion to explain this method, especially before the Academy of Science in Paris, but I am now able to describe an 811 interesting application thereof, already carried out. You will therefore excuse me, gentlemen, for reverting to a matter, the importance of which I have endeavoured to show you, and in which we shall find a new example of the services that can be rendered by refrigerating processes. The first principle of the new method consists simply in submitting the air charged with the vapours to a temperature sufficiently low to reduce their tension to a negligible quantity. In order to obtain this it is necessary to go down to about — 100" C. We shall see presently that, in spite of the extreme poverty of the matter treated, the difficulty does not lie in the economical refrigeration at such a low temperature of the large masses employed, for the special apparatus which the liquid air industry has necessitated has solved this question in advance. The following is a greater difficulty: the air to be treated contains not only the vapours we wish to recover, but also moisture. Therefore, if the air is not dried before it enters the apparatus, constant obstructions are caused by the freezing of water, and the advantages of the non freezing qualities of alcohol and ether can not be expected. But if, on the other hand, these large masses of air are to be chemically dried an apparatus and handling is required which does not possess the desired simplicity, and we revert to the inconveniences of the chemical processes. I have, however, succeeded in avoiding all preliminary dessication with my apparatus, when treating the moist air as it comes from the works. In a word, I have succeeded in extracting in liquid form, and continuously, all the vapours without being hindered in the least by any kind of freezing, in spite of the very low temperatures obtained. For this purpose, the air charged with vapours is compressed to a pressure of about 4 Atm. This has a twofold object. It increases in the first place the tendency to condensation on the part of the vapours, to become, by its expansion, the refrigerating agent necessary for the completion of the process. t After compression the air passes to a refrigerator, a considerable amonut of moisture and a small quantity of alcohol having already been extracted due to the Super-saturation caused by compression. The compressed air then passes to the so called recovery apparatus and rises through a battery of tubes acted on by a simple countercurrent, in which it is subjected to lower and lower temperatures as already explained. Water already mixed with much alchobol is at once condensed at the bottom, the alcohol preventing it from freezing until considerably below 0° C. The air may thus be cooled considerably lower than 0° in the tubular battery without the condensed fluid ceasing to remain in the liquid state, and hence to flow to the bottom. As the condensation proceeds the proportion of water, and the liability to freezing, diminishes, and this goes on indefinitely, so that, as the air ascends into lower temperatures, no inconvenience is experienced because 812 the liquid formed is more and more non freezable, and can easily flow to the warmer parts at the bottom. When the air arrives at the top of the interchanger, it is submitted to a temperature of — 90° C., at wich the tension of ether itself is less than 1/2 m. m., but which is insufficient to freeze it, so that all the vapours are gathered in the liquid state in the bottom receptacle while the com- pressed air rises to the top completely deprived of vapours. This air, compressed, drained and cold, is then conveyed to a suitable machine where it, following my usual process, is expanded while performing exterior work, which again cools it to a great extent, and when at — 120° to — 130° C. it flows from the top to the bottom of the apparatus against the current of compressed air, communicating to it the series of temperatures . whose effects we have just analysed. | H= F- i } | } | | | i } | t ! & | % } | . # % | % } | - % 3× % ! - 6% t % | () % ! - - - - - - - * .* % * É j e %—is à % S * *_* -- T. {2. % Ro! § - | 2. % || ". †† : % || | i–l, iſ % } | {Q9. ###| | # } | | % | | |U|U || || | | Sº % | TET: jºist S. % I - Z, ! | ** i 2 2. | | § {{\ |\ \ . # % | t; | $ I | : : | % % | ; RA - -- *\}: * | | % Ar- * * * * sº | e % | §ºlº) Ø % | * | * FSF === +-----> * ſº º £% % | -: 8 tº | || §: º/, - ź s & ‘2’ º * & s - * * - g * tºº, **** , S3 -“º 2 ~ * . . ., " . " - . . . . • . . " . v.--, 's '... ', ºr ‘s . . . S.-3 (." , -, “‘ r- s^* * Fig. 1. The Arrangement of Plant. The process is indeed so efficient that after the lapse of half an hour, condensation has already begun; in the course of about an hour the air which has passed through the apparatus has but a very faint odour and retains less than 1 gr. ether per cu. m. If we assume an initial proportion of 20 gr. per cu. m., we see that no less than 95% has yielded to the treatment"), let us say 90%, including losses. Moreover, the working of the apparatus is extremely simple. It is not necessary to attend to the greasing of the expander, which takes place automatically by means of the last traces of ether. - 1) There is however, nothing to prevent returning this air, which is quite fit for breathing, to the workshop by a closed conduit and recovering the small quantity of ether. --- 8] 3 The work necessary is thus much reduced, and consists in periodically observing and removing from the gathering vessel the very pure liquid condensed therein. The expense is reduced to the power necessary for compression, and the simplicity of the apparatus is seen by the illustration Fig. 2. • In order to appreciate the economical side of the process, it must be noted that an important part of the energy expended in compression, is regained by expansion. It may be seen in the illustration how the expansion machine returns to the compresser the energy due to expansion. In taking account of this, and noting that for a large apparatus it is sufficient to compress to 4 Atm., we find that it is possible to treat up to Ş NSNSN § NF-7*E* * * * * * ----4--- f H----929 ---- N Nº. d’ory.gene | AAgare/ | APéſºzoº/r Æenvoy/re” | s * T N #% LS - Peters | § § = z =::::::::::--------------------------------------------2' . N !- 73%3a aº aſs/r/ða/º/ §H féserved oxygène comprimé ; | Cozzarasseur § Mo/eur e/ec/r/gue aezo/P ſ --/* * * * * * * * = ! I | | § zººs | ; : §. —w | | +|- N-- - H(--)H- § - - - - - - - !-------------- l : § • l s: §. _{_*za 3” 50 s § N---4----------------, :----------------------------------- - § féserve d'oxygène saär/guide * : N NSN Fig. 2. arº General View. 16 cu. m of air per H. P. hour. If we assume 20 gr. ether per cu. m. we obtain a recovery of 300 gr. ether per H. P. hour. The ordinary cost of one H. P. hour being 0.05 francs, we see what an important margin of gain there is. At present, I believe that I can affirm, after an examination of several cases, that it will almost always be possible, after some trials, to arrive at suitable arrangements without inconvenience to the workmen, for regaining 30 to 35 gr. per cu. m. There should be no other limit to the concentration than the question of safety, and we shall see that this is not affected by the proportions involved. One may thus arrive at the splendid result of regaining 500 gr. ether, say at least 0.35 francs, per H.P. hour. 814 It is, Gentlemen, more than a year since I have published this method, but it seems that simple matters often have difficulty in making their way. My experience with the matter enables me to affirm that with this process the recovery of diluted vapours is quite a simple matter, but until recently I have been unable to prevent a single one of the interested industries to throw away its money, if not at the gates, at any rate through the chimneys, wich is hardly any better. - --- However, this wrong state of affairs is due to a strange legend that has been put into circulation, the author of which is, I think, no one less than M. de Chardonnet himself. I have, to be sure a great admiration for M. de Chardonnet, who places every year 50,000,000 francs worth of artificial silk on the markets of the world; he will, however, allow me to inform him that under the circumstances he is serving his own invention badly, when a good process of recovery applied to it could bring certain victory over all competitors. M. de Chardonnet has experienced a terrible accident in the Hungarian silk works, due to the explosion of a mixture of ether and air at high pressure, and from this reason he will not listen to any proposition involving the compression of mixtures of air and ether. I have explained to M. de Chardonnet, at the French Physical Society, that there could not be the slightest connection between that case and mine, for in that case there were large masses of air saturated with warm ether, suddenly compressed to the enormous pressure of 30 atm., and one could not conceive of a more perfect infernal machine. In my case, however, nothing is involved but proportions of 30 to 35 gr, and modest compressions of 4 to 5 atm. Moreover, I have considered this question of explosiveness, before it has been suggested by M. de Chardonnet, for I have made very numerous experiments, and have determined that proportions of 50 gr. ether per cu.m. are below the explosive limit and quite safe. A slight inflamability does not begin to appear before at 60 gr., and with a warm mixture, that is to say under the most favourable circumstances; with moist air the limit is still higher. To sum up, as high as 70 grams, the over pressure caused by an ignition, for which however we see no reason, would be very slight, and incapable of causing the rupture of a well constructed apparatus. At any rate up to 50 or 60 gr. there is absolutely no danger. However, it is certainly not necessary to go so far, for I have just referred to only 20 gr. as being very advantageous for treatment. The fears of M. de Chardonnet are therefore unfounded, and the new process can be applied with perfect Safety. I have just said, Gentlemen, that I could describe an interesting appli- cation of my process, and as a matter of fact the Société Lyonnaise de Celluloid, convinced by my experiments, has instructed the Société de l'air Liquide to install at its Oyonnax works an apparatus for treating 200 cu. m. air per hour, charged with alcohol emanating from the working room. A specially interesting feature of this case should be noted. The Celluloid loses when worked, besides alcohol, also an appreciable proportion 815 of camphor, which is a valuable product; and it has been arranged to recover this camphor with the alcohol, and the camphorated alcohol which is very pure is regained by the apparatus to great advantage. The Oyonnax installation is worked by a three-phase motor of 25 H. P. The working pressure is somewhat high, about 5 atm., which accounts for the small popularity of the apparatus, and the relatively large losses of cold. The working temperatures are 60° C. at admission, and –110° C. at exit, which is quite sufficient in the case of alcohol. The working of the apparatus has not, it should be noted, presented any difficulties, but some miscalculations were made at the start regarding the recovery of the vapours. To begin with, the proportion of vapour did not exceed 5 or 6 grammes per cu. m. Little by little the results have been improved, and finally proportions of 50 grammes have been obtained. I have mentioned similar difficulties with experiments made at the Sevran Livry national powder factory, and there we have been able to increase the pro- portion to 40 gr. per cu. m. It is from these two test cases that I have formed the conviction that very rich vapours can always be obtained. It should be noted, also, that while the proportion of 50 gr. obtained at Oyonnax was very high in the case of ether, it is quite admissible, here, due to the slight volatility of alcohol. Compression takes place, in fact, in two stages, and a considerable part of the alcohol is already condensed with water by the cooling that follows the first compression; the parts of the apparatus under high pressure receive therefore only vapours contining at least 50 gr., which is the initial proportion. The average of alcohol obtained is 80%, and the liquid is quite clear. At present only the air in the working rooms is treated; it contains a relatively small amount of camphor, and in an average of only 30 to 40 gr. per litre. It is estimated that in time 80 gr. per litre will be recovered With normal and continuous working, the daily recovery by means of this installation will ultimately reach 150 Kg. Alcohol at 90°, and 12 Kg. Camphor, in 24 hours. - 816 Note on the preservation of dead bodies. By M. Charles Jacquin, Paris. Every one knows how troublesome, and at times how little hygienic, is the watching over a dead body from the time decomposition sets in, often very rapidly especially in summer. The remedy which has been proposed, and which consists in sending the body a few hours after death to the municipal mortuary, provided with arrangements under suitable hygienic conditions (for instance refrige- rated in Summer), while allowing the watching, is very rational, but it is a shock to the relations, who desire to keep the body, until it is to be laid on the bier, in the family home where the deceased has lived and expired. M. Ch. Jacquin, an Engineer of Paris, known through Electrical and Mechanical Works, has found the means of reconciling a very legitimate piety with the most exacting hygienic requirements. The process devised by M. Jacquin is simple and practical in application, at any rate in large cities where there are well organised funeral arrangements. When the burial permit has been given by the official physician (which in Paris is done within 24 hours), or as soon as decomposition is noticeable, (owing to fear Of suspended animation), the body stretched out in the bed is placed in a »refrigerating mortuary cases. This apparatus, which has been patented, consists of a wooden box A, at the foot end of which is a receptacle B made of zinc, with an opening b, through which ice can be inserted. The part D covering the head and shoulders, is fitted with glass windows through which the features may be observed until the last moment Finally, in order to avoid the condensation on the inside of this glass of the humid air en- closed in the case, chloride of calcium is placed in the basket P through the opening p, before the ice is put into the receptacle, and in sufficient quantity to absorb all the water vapor in the air. By renewing the ice after it has melted (the water being let out by the cook) one can easily maintain a cold atmosphere within the case, whatever the exterior temperature may be, which will arrest decomposition and the resulting odours, during the whole time of watching, and up to the time of placing the body on the bier. 817 At any rate as the case is entirely closed, but can even be put in communication with the outside air by a simple rubber tube (although this precaution is probably unnecessary), the slight emanations which may arise would not be noticeable in the room. Thus the keeping of the body for several days in the home presents no longer any objection from a hy. gienic point of view, and the relations may be free from the present trouble- some experiences of their watching. This is the humanitarian side of M. Jacquin's idea, and the realisation thereof, which can only be obtained after preliminary trials, is very much to be desired. I therefore propose the following resolution to the Section: In the Sense of this Section, Administrations of funerals (municipal or private), should, in the interest of hygiene and humanity, undertake experiments with the refrigerated casket invented by M. Jacquin, of Paris, with a view to placing apparatus of this kind at the disposal of families. { Bes g D , Verre b t Bois Zirac LD 2 | P l——-l c *s f / 2. i ſ J- & – tact. B *--~ 2/ - S- A —T-- || —TT — T- ~ - – T | – || -- — -* TNS= − - – - -=== aſ / > 2 / 2 × 2 / / / 2 × 2– 2 2 × - I t | | | |vºrrº | TTTTTE=|| – g D T-2′- ====T | No ^ I S s * #i ... " Tº —car \ º * * FS | | | | Will || || Bºul III IT 818 Cooling of Dwelling Apartments. By Mr. Bourgoin, Naval Artillery Engineer. Let us suppose the intention is to cool the atmosphere of premises situated in a country with a high average temperature and low hygrometric pressure. In the Soudan we have a climate of this kind during the period from the 15th March to the 15th June when the measurements of the thermo- meter are known to rise above 40 degrees. If we simply wish to shelter the European from heat it will suffice to obtain a cooling of 6 to 8 degrees centigrade, as, at rest or in the shade, action is only necessary when the temperature is above 37 degrees. On the other hand, as we have assumed a low hygrometric state we need not trouble about the removal of the water-vapour. Within these limits the problem stated may be simply and economically solved by using the evaporation of the water in order to obtain the cooling desired. Indeed, practically by the evaporation of one litre of water an amount of cold may be produced equal to that resulting from the melting of 7 to 8 Kgs, of ice. As to the quality and degree of cold thus produced, they are the result of the following various factors: 3. 1. Temperature of the outward air. 2. Temperature of the water. 3. Hygrometric degree of the air. 4. Rapidity of the circulation of the air. Their influence is such that during the dry season, with a suitable apparatus the surrounding temperature may be lowered by 8 degrees. Plants for cooling premises based on this principle are already in pretty general use in countries within the temperate zone: (The Court Theatre, Vienna, in Spinning Factories, etc.) It must be remarked, in the cases referred to, air is driven directly into the premises at a maximum temperature of 25 degrees and moistened to 50 or 60 deg, whereas, in the tropics, on account of the high tem- perature of the air when driven into the apartments, great care must be taken not to increase the quantity of water vapour originally contained in the air. 819 - In order to attain this desideratum the aircooling apparatus must be fitted up in the following manner (Fig. 1). The air to be cooled drawn in by a ventilator is forced through a thin galvanised iron pipe; this pipe curved several times on the same vertical plane is surrounded by spiky shavings or a mass of crushed coke the pieces of which are held in a metal grating with large meshes. The water to be evaporated is placed in a reservoir above the shavings upon which it trickles through a tube pierced with very fine holes and runs into a cement basin from whence it is driven back into the reservoir by means of an electric pump. On leaving the basin, the pipe, which has a covering to keep off the heat, conducts the air into the building to be cooled and there it is distri- buted amongst the upperparts of the various premises. º Vezzº (a &ecor- 3ozcá e cezzó-dºza's Zeca'-cycze * * <2%-4g.e ; : —- Par-3 &s & co. *m-. --> -- * |- - * - - aer Zazzazzzzz | - ,5c séezzº. - | , ºzº, | | - ! | T- - + T-r |º] 4% woºzas vers Ac/zzzzy t ~2%/zzazza Złºw W2%izzº ------ azz ZA1/A1/62///Z2//4.s. - AZ º Z - Zoo. - . * | e :. 2 --~zizızz's 2x. zzazºº. * - E.J. 2 ZvZvrrxAxizz | \ Zazzzzzzzzz Azzzazz Zazz 44x22:22.7// § s i § s r B . 22.22%22z44? -Zarzzzzºz. - - –4 –’ Żºłszzzz Ż-Z Ž zzrºwzz. * . Z. ("zz/A22:35 sº. 4374-52:/zzz — — — — — — — 835 International Cold Congress in Paris in 1908), were situated within the *- tropics. In the meantime only a few such plants have been put up, but among these one is within the tropics, it being in the theatre at Rio de Janeiro.”) As regards the cooling of dwelling houses in warm zones, we stand to-day on the same level as at the time in which the physicists Sir William Thompson, Rankine and Smyth occupied themselves with refrigeration experiments and with the solution of this problem *) especially. This is due to many causes. The chief one is that cooling with machines, in my opinion the only perfect method, is too expensive for private houses, offices, hospitals and other public buildings in those districts. The expenses of the Andiffren machine are the lowest, yet this machine must, for the present, remain out of consideration, because it is not yet built in such sizes as make it suitable for the cooling of buildings. Where ice and salt are cheaply obtainable, the apparatus by Ingenieur Otto Sterkel, of Ravensburg can be used. Unfortunately ice is so expensive in the tropics, as a rule, that cooling with ice, as described, for instance, by Karl Heimpel, in Vienna," must be considered too prodigal. Where water power is available the expenses of working ordinary cooling machines will be greatly reduced. Now > white coals occurs as a rule only in mountain districts, and in the tropics there is in such districts so mild a climate that the cooling of rooms is unnecessary. Our worthy pioneer in refrigeration, Ingenieur Charles Tellier, Paris, proposed somewhere that well water be used for cooling dwelling rooms. This means is but seldom available in tropical lands, as, cold springs often failing, one is driven for larger quantities of water to the rivers, and such water is objectionable both hygienically and on account of its temperature. For a long time I lived in the tropics (at Batavia ard Sverabaia), and the average annual temperature in the houses I occupied was 80° F (26.7° C), in one even 82° F (27.8° C.) The whole year round the temperature only varied about 2" F. below and about 3° F. above this average, so that it is evident that any reduction of this temperature would be very welcome. This is secured by building houses of stone with a good insulating sºcovering outside and an insulated thick broad roof. Further the ventilation should not be effected by doors and windows but by wall openings at the bottom and at the top of the rooms. This causes a stronger air circulation during the night through the whole house, than do the doors and windows which must be closed to prevent the entrance of persons and animals. 4) Report of the Congress. Vol. I, p. 142. --- *) Described by Oberingenieur Karl Pfeiffer, in nEis- und Kälteindustrie“ for this year. *) See a Kühlmaschinen für Wohnräume", by E. Brückner, in n.2eitschrift für die ge- samte Kälteindustrie“, Nos. 6 and 7, 1899. *) Report of First Congress. Vol. 2, p. 154. 53% 836 A better cooling of the stonework of which the house is built is ef- fected during the night, and this leads to a reduction of the temperature during the day. This stonework is protected against the heat outside and the absorption of warmth from the inside proceeds normally. A ventilation plant to work the airing process during the night would be still better. k From this proposal it is evident that in my opinion the solution of the problem, as said at the beginning, must be sought in another direction to that hitherto followed. - The valuable work by Regierungsbaumeister H. Griesshaber, 2 Moderne Bauten in warmen Zonen < (published: Oldenbourg, 1907) and the interesting article by Ingenieur Max Hottinger on "Die Kühlung menschlicher Aufenthalts- räumes in der Ges. Ing. ‘of 30° July of this year, are in my opinion impor- tant references. In two plans, one for a tropical hospital and one for a tropical dwelling house, Herr Griesshaber makes use of a so-called cold accumulator additional to the refrigerating machine to solve the problem of cooling tro- pical houses in special cases. This idea, which Friedrich Siemens embodied with success in 1856, in his regenerating furnace to secure very high temperatures is here I think proposed for the first time for cooling”) and in a somewhat similar manner, so-to-say, for storing the cold of the night air. The same idea was described by Ingenieur Hottinger among the various means applied for cooling rooms. I do not however know where such applications were made. Both authors describe the effect of the accumulator in the following Iſlaſh 1161 . a. By means of a ventilator fan the cold night-air is drawn through so- called storage ducts cooled by this air through conduction and radiation. Herr Griesshaber makes use of water evaporation to withdraw still more warmth from the canals. By day a fan drives the warm air through the ducts, and it is thus cooled and passed into the rooms. These publications have led me to the following reflections: In general, in tropical buildings, is sufficient cooling possible simply through storing the cold; and is this cooling possible without mechanical assistance! * For the solution of these questions the meteorological statistics pertai- ning to the temperature of the air and earth, the humidity of the air and the force of the wind in the tropical region under consideration are essential to be known for every hour of the year. 1) The application of the so-called regenerator spirals and counter-current apparatus in the gas liquefaction machines of Kamerlingh-Onnes, Linde, Hampson and Claude refer more to the idea of recuperation than to the idea of regeneration. 837. In the short time that I have so far studied this problem, I have succeeded in obtaining such detailed particulars from one tropical place only, namely from Batavia, the capital of Java.") These data, as also those of other tropical places that I have so far been able to consult, lead me to the conclusion that question a) may be answered generally in the affirmative, if one is satisfied with a reduction of the average temperature in tropical buildings of 2° C., which I consider very salutary and which avoids damping the air. In localities with fairly low night temperature a still greater day cooling is possible. The second question can only be answered in the affirmative in special cases. In general, however, it is taken that the airing by day can be effected without mechanical aid, by making use of wind. For moving the large quantities of night air, which will generally be necessary for the storing of the cold, it will be possible only on rare occasions to make use of wind pressure. º I draw the following conclusions that may be considered generally valid for the tropics: - 1. The wind pressure is greatest in the warmest hours of the day. 2. The differences between the maximum day temperature and the minimum night temperature are greater in the warm months than in the cold months. ~ 3. The relative humidity of the air is least during the warmest hours of the day. - - I believe that a sufficient and economical cooling of tropical buildings may be attained by attention to the following conditions: a) The building must be faultlessly insulated in all respects and provided with well closing double windows and doors (the latter with so-called air vents). b) With the exception of the air inlets and outlets the house must be quite closed. Thereby human health and the durability of furnishings will be safeguarded. c) Walls, floors, ceilings, as also ducts, should be of stone of the greatest capacity for absorbing heat º This material must not pollute the air. d) The storage ducts are placed on the ground floor, or if there is not enough room there, or other reasons make it necessary, in the attic. e) The airing during the day is aided by the wind, the in-flow openings being provided with pressure heads and the out-flow with suction heads. 1) Year book: , Observations at the Royal Magnetical and meteorological Observatory, at Batavia. “ - *) The use of water in the canals would be very ſavourable, from this point of view because of all matter it has the greatest specific heat. The use of water in the cold storing ducts has disadvantages, however, and I consider the use of lime-stone best for this purpose. $38 f) The ventilating plant should be so designed and operated that there is a g) slight superpressure in the rooms during the day so that no warm outer air can enter. Care must also be taken that the air introduced into the rooms does not deposit moisture. During the night the air is for the most part circulated through the storer, and a small percentage only goes through the building so that not only cooling of rooms but also of walls is achieved, so that this second storing assists the day cooling. - - The circulation of the night air is done by a fan, but in special cases it can also be done by deflectors if there be sufficient wind. -- The quantity of air passing through a bed-room in one hour should not be more than six times the content of such room, to avoid unpleasant draughts. A) Where dry night air and clean water are available, evaporation of water should be employed in the ducts to increase the storage. Here care must be taken that all water sprayed in the ducts evaporates during the night, so that moistening of the day air may be avoided. For the same reason the use of water during the day is objectionable. 7) If one has cool, clean water, but not in sufficient quantities for com- pletely effecting the air cooling, such cooling can be used additionally. A moistening of the air will only take place if the air be exceedingly dry, otherwise the cooling of the air will generally be combined with a decrease of its moisture. >k >k >k The accompanying figure (Insert Figure) referred to shows a scheme of a tropical dwelling house, which is supposed to be in Batavia, and cooled according to these principles. The arrangment will probably be easily recognisable, without further description, after what has been said above. 839 REFRIGERATION AND VENTILATION OF INHABITED PLACES By HENRY TORRANCE, JR., M. E. Vice-Pres. Carbondale Machine Co., Carbondale, Pa., U. S. A. The object of this paper is to show what has been done in a prac- tical way cooling the large board room of the New York Stock Ex- change in summer for purposes of personal comfort and health. The - -: º --- º Eº. - - - - Fig. No. 1–New York Stock Exchange. air figures are not exact as it is almost impossible to make exact determinations of flow, humidity and temperature. Fig. 1 shows the front elevation of the building on Broad St. almost the entire (east) side being covered with heavy plate glass and since the sun shines in during some morning hours, light curtains are hung which can be raised or lowered. º __ - º - - - - º - º -- *- ºf º -- - º: - - - - - - - - - -- - º - --- - - - - - - - -- i . - - - - __ __ Fig. No. 2–Interior of the Board Room, New York Stock Exchange. Fig 2 shows the interior view of the board room which is 110'x 140'x80' high, aggregating 1,246,000 cu. ft. and there are generally about 1200 people on the floor. New York City Weather. From the U. S. Weather Bureau reports we find that the highest summer temperature is about 90°F. in the day time, the hottest time __ 84.1 being about 2:30 in the afternoon; on such occasions the humidity is usually fairly low, say 60%. In August there is much weather about : 80°F with 80 to 90% humidity, making a slight fog morning and night, and this is the most uncomfortable period of the year on account of the dampness. In the entire summer there are usually about 30 days at various times in which the temperature is 85° or higher and prob- ably 60 days above 78°F. In winter there is considerable weather around 20° and a few days approaching zero. : The humidity is rather high the city being close to the ocean. Following table gives average conditions for the year 1909: Temperatures Maximum Minimum January 51° 5° February • 5S° - 5° March 66° 21° April . . . 80° 24° May . . S3° 40°. June 92° - 53° July - - 92° 58° August r 93° 5S° . . . . September - 79° o October 75° 35° November 74° 30° December 54° 6° •. Equipment of Building. . The building is 140x150, 8 stories above ground and 4 stories (40 ft.) below ground (the building is built on rock and hence the entire excavation was utilized.) The entire building is heated, but only the board room and safe deposit vaults are cooled. - The cellar contains the boilers, (800 horse power,) electric engines and dynamos, elevator pumps, air compressors, pneumatic tubes, telegraph apparatus, refrigerating machinery, etc., in fact it is aston- ishing how much machinery is required to properly operate the building. - f - - General Heating and Cooling System. In cool weather exhaust steam from the engines is used to heat the air blown by the fans, and in warm weather it is used to operate the refrigerating machines which cool the brine which is pumped through the cooling coils. Refrigerating Machines. There are three 100 ton Carbondale absorption exhaust steam refrigerating machines connected to the main exhaust of the heating 842 system by an 8” pipe. When running full capacity these machines require 9000 lbs. exhaust steam per hour at 3 lbs. pressure with 70° cooling water. Each machine has an ammonia pump 16”x?”x16”. There are two duplex steam brine pumps 14”x12”x12” for the main bunker service, one small drinking water pump and one brine pump for the restaurant. All the apparatus is located in the engine room 40' below ground. and during the five years of operation has given no trouble. These three IOO ton machines are started and stopped every day, never run nights, one man takes entire charge of them and no other labor is required. There are no bearings to get hot and no fly wheels to start. Distribution of Brine in Building. The total work comprises: Cooling board room bunker, Cooling safe deposit room bunker, Cooling 12 refrigerators in luncheon club, Cooling drinking water. The figures mentioned in this paper are those which apply to the board room only. No attempt has been made to determine the cool- ing effect used for the other three services. Ventilation. Air is drawn from the roof, about 170 feet above the sidewalk in a brick shaft about 10'x15" and passes through cheesecloth filters, then through cooling coils for summer use, then through heating coils for winter use to the suction of the fans. These filters become coated with dust and are taken out and cleaned once every 10 days by laying them against the suction of a special blower to draw off the dirt. Bunker Coils. The board room bunker, as the plan shows, contains about 20,000 lineal feet of 11/4" galvanized bent pipe with brine headers arranged about 3" centers so brine flows horizontally through coils the opposite way the air flows. Underneath is a copper drip pan. These coils are connected in two sets, but in practice they never get filled with frost and so all are used together. Temperature of Brine and Air. Brine enters the coils at from Io" to 20°F. and leaves about 40°F. One half of the coils are usually frosted, the other half condense moisture which runs off into the pan. At night when the plant is shut down the frosted pipes melt off. Air enters at say 85°F. and is sº Temperature of Room. tained at about 75° to 77°F., say Io” lower than In very muggy 80°F. weather the room Dºrºtºtº-IJº º º ſº *= -- ~ * ./ - - -3- Z 2 / A, / / z -->;-- ŽT Xºs Z./ * X Ö/ ¥ SE- U.S.- Jºliº- 3. yet twentismo scoºp § W t Fig. No. 3. Humidity. 1S 1113,111 : , ~//wºſ ,Èå w、 |H_PĒ - Main Floor Plan of the soard Room showing Air Exhaust System. cooled to 60°F, and is then heated by the fan and radiation of ducts to about 65°F. by the time it enters the top of the board room. The room the outside atmosphere. -r-, ſillſ|| |-||-||||||||||||×]><ſ EË - - ~*~FĒ） || || L.__ kept only about 4°F. cooler than the outside air, though much 1S drier. In extreme hot weather, say 95°F., the room is fully 15° cooler. The humidity of the air leaving the bunker coils is about satu- rated at 60°F. as it has been cooled to the dew point, and contains about 5.7 grains of moisture per cu. ft. 844 Volume of Air. The space in board room is about 1,246,000 cubic feet. The fan when run at 110 r. p. m. delivers about 50,000 cu. ft. of air per minute which enters at the ceiling, and a slightly smaller amount is ex- hausted at the floor by a separate fan. The air is thus maintained at about the same temperature all over the room and the vitiated air containing an excess of carbonic acid is thus removed at the floor where it naturally collects. - ~. Power to Drive Fan. . The fans are electric driven and the board room fan takes about 25 H. P. for delivering 50,000 cu. ft. air per minute and reducing this to heat units and allowing 15% frictional loss we get 1000 B. T. U. or 5 tons cooling effect lost by the fan which never gets to the room, this being about 2% of the total capacity. Brine Tank. % This is 40' long, 8' wide, Io' high, which serves to steady the load, which is very heavy at noon time and light in the morning. Hours of Operation. The machines are usually started at 7 A. M. and at 9 A. M. fan is started and cold air is blown into the room. The fan is stopped at 3 P. M., and the machines are run till 4 P. M. cooling the brine down to Io"F., ready for next day's work. & Heat of the Room. The following figures give the calculations of the flow of heat to the room per hour:- * - B. T. U. Window surface 98.55 sq. ft. (3) 1.25 B. T. U. × 10 = 122,200 Doors º 168 sq. ft. (3) 1.45 B. T. U. x 10 = 2,440 Outside Wall 7369 sq. ft. (3) .07 B. T. U. x 10 = 5,270 Skylight 1024 sq. ft. (3) 1.1 B. T. U. x 10 = 11,264 Allowance for heat of sun through window (estimated)= 32,826 Total transmission . & --. 175,000. Animal heat from 1200 people at 400 B. T. U. per hour 480,000 - Total British Thermal Units 655,000 Tonnage 54. The transmission is based on 85° outside and 75°F. in the room and the radiation constant used is the same as that used for heating buildings in New York City. Air Required to Cool Room. When one cu. ft. of air enters the room at 60°F. and is raised to the room temperature of 75°F. it will take up heat equal to o.238 (spe- 845 cific heat)x0.075 (1bs. per cu. ft.)x15°–.267 B. T. U., hence a cool- ing effect of 655,00 B. T. U. requires 655,000–267=2,452,800 cu. ft. of air per hour = 40,880 cu. ft. per minute, say 40,000 cu. ft. The following calculation shows the cooling capacity of the refrigerating plant for cooling this 40,000 cu. ft. from the outside Fig. 4.—Exhauster for Cleaning Air Filter Frames. temperature 85° and 85% humidity to 60°, Iooºº humidity (the air leaving the bunker coils is about saturated). To cool air:- B.T.U. 40000 cu. ft. (85°-60°F.) x. 23.8 s. h. x. .075 lbs. per cu. ft –17840 Air at 85’, 8.5% humidity contains .00154 lbs. per cu. ft. -- at 60°, 100% -- -- 000S -- -- -- Difference condensed out 0007.4 40000 cu. ft. x. .0007.4x966 (latent heat condensation)– 2859 This moisture must also be cooled to 60°F, and some is frozen on the pipes requiring a cooling effect of about 40000 cu. ft. x. ()007.4x30 88.80 Total B. T. U. to cool air 55312 Equivalent in tons of ice cooling effect in 24 hours 276 846 Summary. This figure of 276 tons ice melting effect required to cool the room to 75°F. is the theoretical result, and it is interesting to note that in practice this is just about the tonnage required. There is a ;: Cº'Cº'Cº'Cº'Cºfiñº-F- * * * ſ - tº 34 º: s nº. º º s-wºº. . ;:S - º º > º --- º *º *Rº º º ºrs º - #Hººtºrºtºrsº (A pººr *: ===#: a-ºº: ===####; - Hº-ºr-º-º: |S.; ; – o O O. #: o 'o "oº-ºº! & i são ; : §§ {|| Si→o O O ! ! 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L. ..J.J.- -1.1. ..J.J. if r- - - - - - - - - - - - - -, º;247 or * - - - - - - - ----- -l *—º -h -> ſº- fºliº Callery Plan of the Board Room Showing Air Supply System. - Fig. No. 5. - radiation loss in the bunker and ducts not shown, but on the other hand the atmospheric conditions are generally not as bad as shown and the following figures form a pretty close estimate of what should be provided for a building of this character. . - 847 Size of room 1,240,000 cu. ft. Temperature of room - 75° to 78°F. Outside conditions 85° 85% humidity Cu. ft. fresh air blown in per minute.-------------........ 40000 to 50000 cu. ft. Maximum tonnage required to handle this work 276 Usual tonnage 200 to 220 Cu. ft. in building per maximum ton -4500 Sq. ft. exposed area in building per maximum ton 670 Moisture Removed. The humidity of the room runs 65% to 70% and by actual test it was found that the condensed water from the board room bunker coils running off from the pan underneath was 2,000 lbs. per hour, showing that at the time the water was weighed the above theoreti- cal figures were slightly exceeded. Coal Consumption. In April and May there are many days when there is no cooling and no heating, which enables the coal consumption of the refrige- rating plant to be determined, and it is found that the coal consump- tion of the building is then only 1% tons of coal less per day than in summer when the plant is run at full capacity for 10 hours daily, thus this 300 ton refrigerating plant is shown to require only 1% tons of coal in addition to the exhaust steam otherwise wasted, and is probably the most economical refrigerating plant ever installed. This coal consumption corresponds almost exactly with the coal that we would expect the brine and ammonia pumps to use when doing this work. * Cooling Effect Calculated by Brine. The brine pumps delivered 280 gallons of chloride of calcium brine per minute at 20°F. to bunker coils; leaving at 40°, range 20°, total tonnage about 250, which agrees with the theoretical figures above. * Comparison Between Total Tonnage Delivered and that Required to Overcome Heat in Room. From the above we observe the heat in the room takes about 54 tons and cooling the incoming fresh air takes 276 tons. When we close the windows the room will naturally rise in temperature due to the occupants radiation and sun, hence consider- able cooling must be done to bring in air for ventilation and take care of this heat without cooling the room at all, this might be termed the fixed expense which we have to endure before realizing again. 848 { This figure could be obtained practically by raising the inlet air temperature till the room remained at the same temperature as the outside air. This test was never made as, medless to say, it would cause too many complaints but it can be figured as follows: The heat entering room in B. T. U., assuming the temperature in room was 85°F. (the same as outside) would be as follows: } Radiation ; 0 Assumed sun’s rays (see above) 32826 Animal heat 1200 people 480000 * 512826 When I cu.ft. of air enters the room at 60°F. and is raised to the room temperature of 85°F, it will take up heat equal to .238 (specific heat) x .075 (lbs. per cu. ft.) x 25° = .446 B. T. U. hence a cooling ef- fect of 512826 B. T. U. would require 512826 = 1150000 cu. ft. per 446 ^ hour = 19200.0 cu. ft. per minute. -- Requiring a cooling effect of 19200.0 x 55312 = 26550 B. T. U. 4.0000 per minute = 133 tons. (See above.) This would mean that 133 tons are needed to keep the room as cool as if all the windows were open, and would really do no good whatever and less than 133 tons would give poorer results than open windows. ~ This point has frequently been overlooked, plants too small have been installed, and when the windows were closed and the machirie started the room became hotter instead of cooler, and machinery, had to be shut down, being a total failure. - Future. In very hot weather it is customary for restaurants to have elec- tric fans all over the room, which cause draughts and also cool the food, in fact such fans are worse than useless, but the restaurant keepers feel they have to provide them. Such dining rooms should have ventilating and cooling plants, and since by improvements in machinery and methods the price of such machinery is constantly be- ing reduced, the day will soon come when all first class restaurants will be so equipped. 849 THE APPLICATION OF REFRIGERATION TO THE RETARDING OF PLANTS AND THE PERSERVATION OF FLOWERS By PROF. L. C. CORBETT, United States Department of Agriculture, Washington, D. C. The modern commercial nursery handles such an immense vo- lume of stock, of such a varied nature, and possesses a patronage scattered through so wide a territory, that in order to successfully han- dle and pack the product and deliver it for spring planting, the old prac- tice of heeling in the stock has been abandoned to give place to the modern system of storing in retarding houses. The season for handl- ing the stock is so short because the plants start so quickly in the spring, even when dug in the fall and heeled in according to the old practice, that it is practically impossible to operate extensive nurseries on such a basis. Small nurseries and plant gardens, designed to meet the requirements of local purchasers only, can be successfully operated without retarding buildings or the intervention of cold storage. In extensive enterprises, however, where the sales lists reach thousands of people, and where the distribution is made through a number of states possessing a variety of Soil and climatic conditions, the dis- tribution must extend over a very considerable period of time, a period of time much greater than is allowed by the normal behavior of the plant; therefore artificial means must be resorted to in order to hold the nursery stock in suitable condition for shipment, to pro- vide for this wide distribution. Types of Structure Used for Retarding Purposes. The type of structure best suited for the work of storing nursery stock is determined by the amount of stock to be handled and the location of the nursery. In those sections where long, uniformly cold winters prevail, the cellar or half underground structure is very satisfactory. Further south, where conditions are less severe, and where there is greater variation in temperature within short per- iods of time, the aboveground type of structure, insulated by pro- viding multiple partitions of boards and paper in the outside walls, gives better satisfaction than any other type of structure. In these 54 Southern territories cellars become too damp and are influenced by soil temperature during the late spring months to such an extent as to greatly lessen their usefulness as retarding houses. The above- ground structure, with walls packed with sawdust, is not satisfact- ory because the humid condition which must be maintained within the structure, in order to successfully preserve the nursery stock, greatly lessens the life of the structure. At the same time a moist wall packing is a less efficient insulator than a dry one. Air spaces are, therefore, most satisfactory, particularly if the spaces are made horizontal, rather than perpendicular, so as to prevent rapid circu- lation of air. It is necessary that these buildings be frost-proof, as well as capable of holding or retaining cold temperatures for a long period. Large structures, designed for this purpose, are built on a unit Scheme. There are different storage rooms provided, each room being stored with material for a given geographical area. Those containing stock to be planted first are emptied quickest, and those which contain stock to go to most northern localities are not opened after the temperature has been one reduced, more than is absolutely necessary, until time for packing out arrives. Besides being built on the unit or room plan, these buildings are provided with ventilating appa- ratus which can be controlled to regulate the circulation of air in the rooms as much as possible. While circulation of air is desirable, great caution is necessary in ventilating the rooms to so manipulate it as to allow the entrance of air only at times when the temperature of the room will not be raised above the desired point, or lowered beyond the Safe limit for the stock in storage. Deterioration in stored stock is largely due to changes in humidity within the storage house, brought about by fluctuations in temperature. Uniformity of temperature is of greater importance than low temperatures. Besides the value of the retarding house as a means of facilitating the work of the nursery during the digging and packing season, the re- tarding house is a great safeguard to the nurseryman. Little stock is injured from storage in buildings with a uniform temperature, as com- pared with the loss of stock which is dug and “heeled in.”. Much stock was lost under the old system from severe winter conditions, but be- cause the temperature is never allowed to reach the danger point in the retarding house, this is not possible. Storage houses are, therefore, a great safeguard to the business. In addition to the storage house or retarding house, a number of American nurserymen have provided an additional precaution for the purpose of maintaining a low temperature in the storage rooms much later in the season than would be possible 851 under ordinary warehouse conditions by the installation of artificial re- frigeration, consisting usually of a brine circulating system with ice or with ammonia coils as the cooling medium. It has been demonstrated that if stock can be maintained at a temperature of 43°F. in the storage room throughout the storage period, it can be kept fully twelve months without severe injury or great loss. It is a very easy matter to hold stock six or eight months under this temperature without marked dete- rioration. Some extensive operators who do not possess cold storage facilities of their own have devised a system by which they utilize commercial cold storage to a large extent, to facilitate the handling of their business. The plan of procedure is to harvest the stock dur- ing the months of November and December, immediately pack the trees and shrubbery in paper-lined packing cases, providing proper packing material in the shape of sphagnum, rather than straw, and immediately place the cases so packed in cold storage, allowing them to remain until required for immediate planting. This practice is chiefly confined to nurseries operating in the extreme southern por- tions of the United States, who have a large patronage at the North. The early germination of the stock at the South would prohibit the delivery of the trees in satisfactory condition at the North at the proper planting season. To overcome this difficulty the above prac- tice has been inaugurated with very excellent results. Under this System the packed stock is held in cold storage for a period of three or four months, but practices at the North require that the stock re- main in the retarding house from six to seven months. Holding Nursery Stock From One Season to Another. Attempts have been made to hold nursery stock over a season in cold storage. The experiment was only moderately successful; in fact, not considered sufficiently successful to warrant the plan as a commercial practice. The practicability of such a procedure, when necessary in moving plants from one quarter of the world to another is demonstrated, but the commercial value of such a procedure on an extensive scale is quite out of reason, from the fact that cold stor- age space is expensive; nursery stock is bulky and the value of the stock will seldom justify the outlay necessary for holding it through a long period in cold storage. Short storage periods, however, can be justified for the reasons above stated. Classes of Nursery Stock Which Will Permit of Storage in Retarding Houses: All classes of nursery stock are handled in retarding houses but the whole practice is based on empirical rules. No carefully planned 852 tests have been carried out to determine the conditions best suited to any particular class of stock, or for the general purpose house. Modern practices have developed to meet the requirements of the trade and have been quite as much influenced by economic condi- tions as by the actual requirements of the stock. The whole field of storage, as applied to the nursery business, is a virgin one for the investigator. The necessity for retarding houses requires no argu- ment. Their economic value is demonstrated, but the details of handling various kinds of stock, the benefit or injury to the stock, as well as the effect of fluctuating temperatures and humidities on the vitality of the plants held in storage, are questions which our present knowledge fails to answer. Cold Storage in Floriculture: Low temperatures have long been an important factor in vari- ous departments of Floriculture. In fact, a number of the most im- portant commercial industries connected with floriculture are based upon the use of cold storage as a factor in their development. The forcing of many plants both woody and herbaceous, is made more certain and more remunerative through the use of cold storage. The forcing of polyantha roses, of hydrangeas, lilacs, spireas and the like for the Christmas trade are all more certain if the plants have been placed in cold storage for a short period. True it is, that the gas treatment now promises to provide another means of accom- plishing like results, but the field is yet a new one and full of un- certainty. The forcing of several of the herbaceous plants, such as the lily-of-the-valley, Lilium longiflorum and Lilium Harrisii, are expedited by cold storage, although it is not an absolute necessity to success. The modern handling of lily-of-the-valley is almost entirely based on the successful treatment of the pips in cold storage. In fact, many plants and seeds which require low temperatures in order that they may make satisfactory growths, can be handled in cold storage to advantage. The success of the modern cut flower trade is due largely to the fact that the standard flowers of the trade, such as roses and carnations, lend themselves to storage. While we have no accurate information, based on careful tests, ex- cept that provided by Mr. J. Vercier, Professor of Horticulture in the Cote-d'Or, on The Utilization of Artificial Cold in Floriculture, which is published in the L’Industrie Frigorifique, florists all well know that the value of both carnations and roses is greatly enhanced by subjecting them as soon as cut to a chill, which is just sufficient to check the normal vegetative functions without destroying them. ^. 853 The check should be severe enough to cause the flowers to rest for a period, but the rest should not be a permanent one from which they cannot be roused. Experience has demonstrated that the condition obtaining in the ice-box or refrigerator where the atmosphere is highly charged with moisture is better suited to the purpose of the florist than the same temperature maintained artificially when the air is dry. Usually the chilling is not long continued but it is generally believed that a few hours exposure to a low temperature greatly 1engthens the period of beauty and usefulness of roses and carna- tions. While these practices are of great economic value, even at the present time, there is no reason to doubt that through careful investigation their value might be greatly enhanced. The wholesale flower trade of the great cities of the United States is now greatly facilitated by the use of modern cold storage appliances. While low temperatures are not desirable, a constant tempeature of 40° for carnations and roses is absolutely essential. Fluctuations in temperature and humidity produce great injury, while a constant temperature at a moderate degree is the only means of holding delicate flowers over a long period. Such delicate blos- soms as orchids cannot be held in storage at all. They are very sen- sitive to low temperature and cannot be successfully stored. What we at present need, are carefully conducted cold Storage tests with each of the important commercial cut flowers, coupled with pains- taking physiological researches to determine the exact temperature and its duration, in order that the stability of the flowers may be preserved to the greatest extent and that their duration in an ordi- nary living room after their withdrawal from cold storage shall be greatest. Without these painstaking researches we can never arrive at satisfactory commercial practices. The empirical rules which are followed today serve a very useful and valuable purpose. . The value of the cut flower trade in any European country or in America is sufficient to justify most painstaking and careful research along this line. It is to be regretted that more positive information cannot be given upon these important phases of the cold storage business at this time, but my studies have thoroughly convinced me of the necessity for careful and extended research into these most important commercial fields for cold storage. 854 Application of Artificial Cold in Plant Cul- tivation. By P. de Vries, Reichsgartenbaulehrer at Aalsmeer (Holland). In that great flower district, Aalsmeer, near Amsterdam the cultivation of plants during the winter months has in the last few years attained a great importance, and has led to a large inland and foreign trade in cut flowers. The principal forcing plants are: lilac, guelder-rose, roses, Prunus triloba, Malus Scheideckerei, rhododendron, Deutzia Lemoinei and Gracilis Magnolia, Convallaria, etc. Experience has taught that the plants may be better and more easily brought to blossom if they have been previously subjected to a considerable degree of cold. Winter frosts being often late in making their appearance, fifteen flower cultivators at Aalsmeer made trials, under the direction of the government gardening expert, in order to ascertain whether artificial cold would give results as good as were obtained with natural cold. A freezing room of the Cold Installation Vriesseveem in Amsterdam was rented for the whole of November 1907 so that during four weeks sendings could take place consecutively. Next a minimum temperature of — 67° C (200 F) was taken. The first time, on 31 October, 457 lilac plants, 31 guelder roses, 28 Prunus triloba, 20 Malus Scheideckerei, 7 Rhododendrons, 1 Magnolia and 22 small boxes of Convallaria were sent. This quantity was far too large for the freezing room which was 9 metres long, 3 m broad, and 3 m high. After three days the thermometer stood at — 17.2° C (10 F). - * The ammonia pipes of the cold room were covered with a thick ice- crust, which could not be removed because the whole space was filled with plants. - * Some were then removed to a large department where the thermometer averaged — 67° C (200 F). Five days later, when the plants were taken out, it was already evident that various specimens had suffered through the severe cold, and later on, during forcing, it was also ascertained that those plants had suffered severely 855 which, before being subjected to this cold, had not had completely ripe branches. Most of the Convallarias placed in this room were frozen. In the rented room the temperature, which was regularly taken note of, varied between — 289 and — 4.4° C (27 and 249 F). • Those plants which were subjected to this degree of cold looked very well so that it was determined in further trials not to allow the temperature to sink below — 4.4° C (24° F). In order that the cold might penetrate well and quickly to the plants care was afterwards taken that the plants, both branches and roots, should be brought into the room as dry as possible. Further not more than three layers were placed lying loosely one upon the other, and sufficient room was left free that the ice might be removed from the pipes, if necessary. - A few hours before the plants were taken out the temperature was gradually raised in order that the plants be slowly thawed, as there was otherwise danger of the buds bursting, especially in the case of lilac. The whole four sendings consisted of 1386 lilac bushes, 181 guelder roses, 125 Prunus triloba, 46 Rhododendron in var., 25 Malus Scheideckerei, 26 Deutzia, 10 Golden rain, 5 double almond blossom, 5 Robinia Hispida, and various other plants, with 54 boxes Convallarias, 2 boxes ranunculus and 1 box Spiraea Floribunda. The transport, the placing in the cold room and removal from the Same were attended to solely and entirely by the cultivators, so that they were effected with the greatest care possible. The lilac, which is the best plant for cultivation, and which, too, received most attention in the trials, was variously prepared. Each grower in Aalsmeer received back his own plants and brought them to flower together with other plants of the same sort, which had been similarly treated though not with artificial cold. During the growing the trials were controlled by a special commission chosen by the cultivators. & In general the results with lilac were very good, since the plants blossomed excellently and at a somewhat lower temperature. Some trials showed that it was of advantage to remove the foliage in advance and to keep the plants dark for some weeks, other trials showed such procedure to be not absolutely necessary. It was generally evident that the plants with good and ripe branches gave the best results. Lilac treated similarly but not subjected to artificial cold gave bad results. The result with guelder roses was, unfavorable, not surpassing those which hod not been exposed to the cold. - 856 The fact that the branches of these plants were not yet ripe is probably due to their slow growth. It is, indeed, possible to get ripe branches from pot plants, but these branches are much shorter and are of little value in the flower-cutting business. *- - , , , ; In the cases of other flowering bushes little or no noticeable difference was apparent between those which had been in the cold rooms and those which had not received any cold treatment. Helleborus also gave little satisfaction; the Spiraeas on the other hand bloomed well. - - . . . Booth German Dutch Convallarias gave excellent results. The bulbs developed very regularly and gave blossoms of excellent quality. Other Convallarias, which had not been in a cold room, gave very bad results under the same treatment. • X The Convallarias were put up in little boxes, dry Sphagnum or dry pot earth being used in packing. - Both stuffs were excellently suitable and as regards results do not show any difference in the cultivation. Retarding. The trials were made with the object of finding out how far it was possible to delay the development of various plants by means of artificial Cold and to make them blossom later than usual. Among the plants set apart for the trials were besides the plants ordinarily cultivated, also some kinds that so far have been but little forced. * * At the end of January 1908, before the plants began to develop, 5 baskets with similar contents were carefully packed and sent to the cold room *Vriesseveems in Amsterdam. Each basket had the following contents: 6 Lilac Mary Legraye with pot earth 2 Malus Scheideckerei o 33 3) 3 Deutzia gracilis 35 33 93. 2 Prunus triloba 33 33 39 Further, from the « full soils : 50 Convallaria majalis (Dutch extract) 25 35 , (German , ) Prunus triloba Azalea mollis Rhododendron (Prince Camille de Rohan) Diclytra spectabilis ... " Astible (Spiraea) floribunda Paeonia officinalis Paeonia chinensis 857 1. Pyrethrum hybridum 1 Iris laevigata 1 Iris florentina. On the first day of each of the months July, August, September, October, and November a basket was sent to the experimental garden at Aalsmeer, in order to be brought to flower in the hot-house there. At that time the plants were subjected, in a freezing room of the Vrieseveem, to a temperature of from — 0.6° C to — 17° C (31 to 29°F). The leaves of Rhododendrons in the first sending, which had been five months in the cold rooms, looked a dull green on arrival and the buds were soft. In the hot-house the leaves turned brown and died; such was the case also with Pyrethrum. The lilac developed splendidly, and gave, without exception, beautiful flowers, equal to those brought to flower in winter under ordinary circum- stances. On 21 July they were in full flower. The Prunus triloba blossomed in 14 days, i. e. On 15 July, and although the branches were not so thickly covered with flowers, as had been desired, yet this must not be ascribed to the trials, but must rather be put down to the bad summer of 1907. The Malus Scheideckerei and the Convallarias also developed favourably and, like the lilac, were in full bloom in three weeks. The Iris leavigata gave leaves but no flowers; the Iris florentina flowered on 27 July (i. e. after four weeks), with various stalks. The Deutzias developed badly and gave few flowers. Perhaps this too must be attributed to the previous unfavourable summer. Of the Azalea mollis one specimen gave only shoots, while the other was covered with flowers. The Paeonia chinensis buds shrivelled up, while the Paeonia officinalis at first developed well but afterwards rotted, evidently also Owing to the warmth of the hot-house. The Astilbe floribundi developed well and normally. The plants stood at a temperature of 16–22°C, and even then seven weeks were necessary to bring the blossom fully out. Of the following sendings it may be generally stated that the longer the plants were left in a frozen state the more they suffered and the worse were the results. --- *- It is true the second and third sendings of lilac still gave good re- sults, but each later sending showed more unfavourable results. With the exception of the Rhododendrons and Pyrethrum, which never gave a sign of life, the holding back by frost did not seem to be in any way bad for the plants. The specimens of the first three Sendings grew well in full soil with hardly a single exception. The fine late summer was very favourable to this growing. The trials were repeated and continued during the following winter. $58 In mid-January two large baskets were carefully packed, each with the following contents, and made use of for trials: 4 Lilac Marie Legraye, heavy bushes. 4 Prunus triloba 2 Malus Scheideckerei o 33 5 Paeonia chinensis l’Incroyable. 5 Paeonia officinalis rubra plena. 50 Convallaria majalis (German bulbs). 50 Convallaria majalis (Dutch bulbs). 5 Astilbe (Spiraea) floribunda. Whereas the Paeonies of the previous trials had been taken from full soil shortly before being sent, the Paeonies of this sending had been potted in August and had in consequence formed good masses of root. The plants were kept in the baskets in the cold room at a tempera- ture of — 1" C. On 21 July, i. e. 61/2 months later, the first basket was fetched back. Just as in the former trials the plants were unpacked im- mediately and put into a hot-house. None of the plants died; the Malus Scheideckerei, alone, had dead branches and later on gave base shoots. The Prunus triloba grew well and even the tips of the branches were healthy; but the plants gave few flowers. The Lilac developed fairly well; on 24” August, i. e. after full three weeks, 20 branches from these plants, covered with beautiful flower, were sent to the horticultural exhibition at Zeist. The pot Lilac, however, of the previous year flowered still more beautifully. }} , 33 The fact of the panicles being thinner, however, may very well have been due to the warm weather in the middle of August, whereby, in spite of thorough airing and uncovering, the temperature of the hot-house was higher than was desirable for growing strong flower panicles. -- Events showed that the Spiraeas had gone through their cure ex- cellently. They developed normally and flowered again very well (after about seven weeks). - The Paeonies, now prepared in pots, were distinctly better than in the previous year. Probably this must be ascribed to better preparation. The Paeonias chinensis grew well, but did not blossom. The Paeonias officinalis blossomed after about nine weeks with some- what weak flowers. The second basket was fetched on October 15* . The results of this sending were much worse. The Dutch bulbs of the Conwallarias were good, though not so good as those of the previous sending. The German bulbs did not flower. 859 The Astilbe (Spiraea) flowered again just as beautifully as before and also after seven weeks. -- +} Of the Paeonias officinalis, two plants had beautiful, healthy buds, but they gave rather small flowers. The Prunus triloba and Malus Scheideckerei were dead. The Lilac had brown buds which did not develop, though otherwise the plants were healthy. - On the basis of these delaying trials the following concluding senten- ces may be drawn up; 1. For these trials use first quality plants and bushes with well ripened wood; 2. Send them early, e. g. beginning of January, that the plants may be as much as possible at rest; 3. Care for a small loss of sap during the “freezing” and employ a temperature of — "/" to — 19 C; 4. Protect the plants, in frozen” state, against injury. 860 The Application of Refrigeration to Silk- Worm Culture. By S. Primo Favero, Director of the 2 Instituto Bacologico del Consiglio Provinciale d'Agri- - coltura & at Trento. 1. There are now no limits to the industrial utilization of refrigeration; its employment has created nothing less than a revolution in the commercial and industrial world, increasing immensely the ease of production, preser- vation and handling of many products. We cannot yet estimate at anything like their proper value the enor- mous benefits which the utilisation of refrigeration has conferred on many industries, since we are still in the initial stages of a considerable number of the applications. It is certain that when familiarity with the method of producing cold artificially is more general, the advantages obtained will vastly exceed those already enjoyed. .* One of the first industries to profit extensively by the artificial pro- duction of cold was the cultivation of silk-worms. Subsequently silk pro- duction — an industry closely allied — made efforts to avail itself of this means for killing and drying the chrysalides. The experiment did not, however, turn out successful, although conducted on the most approved practical lines, since it was not merely a question of killing the chrysalis, but also of drying the coccoon, i.e. of extracting in a very short time all the moisture therein contained, which, as is well known, amounts to about */s of its, own weight. Had only the death of the chrysalis by means of cold been desired, sufficiently good results could have been obtained, although the time re- quired was long in comparison with that required by other methods in use. But with regard to the seasoning of the coccoons, it will at once be apparent that in view of the enormous quantity of moisture to be eliminated from the coccoon, cold air does not reccommend itself, being itself almost at the point of saturation and, therefore, unable to absorb in the shortest possible time all the moisture to be withdrawn from the coccoon. On the other hand, in the cultivation of the silk-worms, cold is to day. the most active aid at the disposal of the keen silk producer, who is not 861 slow to appreciate the fact, and obtains it by artificial means when it is not available naturally. - It is well known that while the worm is in the germ state, after having been exposed to a low temperature for a certain period (about 40 days), i. e. near freezing point, the activity of the embryo begins, and that after some time proportionate to the duration and increase of the temperature, the birth of the worms begins. As this must coincide with the development of the mulberry leaf which serves to nourish the worm, naturally the birth of the worm must be retarded until the leaf is matured. And it is just by means of cold that one can retard birth so that it shall tuke place at the proper time. It is also well known that the embryonic activity of the germ-grub is sus- pended about a week after the laying of the egg by the moth; and this activity is confined to the formation inside the egg of the so-called ger- minal protoplasm, which is the rudimentary stage of the future silk-worm ; while the greater part of the interior of the egg is composed of the nutri- tive elements which go to nourish the embryo, and to complete it later on, for the formation of the silk-worm, when the so-called hibe r n a ti on is over. - It is by means of artificial cold that embryonic activity is suspen- ded until the eve of incubation of the seed itself. If not so suspended it would commence with the first temperate days of early spring, which are not always precursors of normal spring weather and temperature, the season being so variable. In this way the embryo develops activity under favorable conditions, deriving the greatest possible benefit from the nutritive matter contained in the egg, which contributes to its vigor and consequently to its regular and satisfactory birth. - In this way it is also possible to foretell the time of birth with more or less certainty, which is very useful knowledge and which it is important should be as exact as possible, the calculations being based on the period of the proper and actual gestation of the seed, and on the necessary degree of heat required, according to the variety of the seed, to force the birth of the worm. - Cold was also used to preserve yearly breeding seed for summer and autumn rearings; that is to say, seed which should have opened in Spring was preserved by cold until the beginning or end of Summer, and then made to open in order to serve for the summer or autumn broods. People who cultivate on a large scale, however, prefer to procure the birth of the annual spawn by other means, such as electricity, immersion in acids, and the like, treating newly-deposited eggs, as I maintain, with better results, since the seed preserved in cold longer, than normally is bound to suffer to a certain extent, since the germ to keep alive must consume. the reserve of nourishment contained in the egg without profiting by it to 862 the full extent, in consequence of which the said nourishment will be found to be inadequate for the longer period when the embryo has attained maturity, and this will probably make the silkworm less healthy and robust than would have been the case had birth taken place within the normal period. Also, cold is utilised by the silk cultivator for retarding the birth of those moths which are intended for the production of eggs. In the modern rearing of cross-breeds it is not always possible to have at disposal in equal proportions the quantity of chrysalides requisite to produce the number of moths necessary to procure the hybrids; it is, therefore, necessary to force or delay the birth of certain lots of chrysalides. For the latter pur- pose cold chambers are specially adapted, frequently artificially cooled, and by this means the birth of the moths can be delayed some days which is nearly always sufficient to attain the desired result. No damage has actually been observed to result from this process, even when the cold applied was somewhat intense. It is also important to note the intimate effect of transit on the hibernation of the spawn, and on this account transit should be effected in Spring before the slightest move- ment has begun in the embryo, thus the seed should be preserved in the refrigerator until the day of shipment, so that the fluctuations in temperature to which the seed itself may be exposed during the journey can have no disastrous effects, and so that whatever activity may be induced in the embryo during transit, owing to its having been brought into contact with higher temperatures, will be only in its first stages, and can then be conti- nued by means of regular incubation. As can be readily understood, one of the most critical periods for the preservation of the spawn is the spring, and it is not too much to say that many of the failures in the rearing of silk-worms are due to the faulty preservations of the spawn at the beginning of this season, that is to say, when the germ begins to develop, and to enter upon that marvellous vitality within the egg, in which the precious silk-worm has its origin, In the past, it was the custom to send the egg-worms for early spring preservation to Alpine districts; but the system was attended by numerous risks in the shipment of the goods, and in having to leave them in the hands of people who could not be relied upon to give due care to their precious charge. On the other hand it was not always possible to maintain the desired temperature in the manner demanded by the exigencies of systematic pre- servation. Nowadays the silk-rearers who have recourse to this method are very few, except in those very rare cases where their vicinity to especially suitable spots, coupled with special facilities for transport, make it practicable. To obviate the difficulties mentioned and gain the required advantages it was proposed that refrigerators should be constructed on the premises of the cultivators themselves, and some firms constructed and had installed complete refrigerating apparatuses. 863 . It was seen at once, however, that on account of the costliness of these immense devices, the expenses of installation, and working charges, they were not adapted to the needs of the silk breeders. And seeing that the temperature to be maintained around the spawn had always to stand between 0° and +2° Centigrade, small refrigerators operating simply with ice would evidently have served the purpose better. The principle on which such appliances are based is the possibility of introducing into them air previously cooled and dried, the drying being principally achieved in the cooling process; the effect aimed at is to surround the spawn with the fresh dry air necessary for the respiration of the spawn, keeping the temperature as even as possible. For this purpose small chambers well insulated from external influences have been found very useful, in which one or more metal tanks containing ice are place through which pass spiralpipes for conducting external and previously cooled air into the interior of the apparatus, which air then finds exit through other apertures suitably arranged. The silk rearing establishments nowadays that have not one of these devices are very few ; they usually work very satisfactorily being of simple construction. In northern Italy they sometimes make use of natural grottoes conti- nually traversed by a current of cold air which issues from underground and which is always of a mean temperature in the near neighbourhood of zero, and which is very dry. These grottoes suitably preserve the spawn for the various growers of the neighbouring districts, who find it more convenient than preserving the seed on their own premises. Also in Japan this system is much in vogue, and a recent work pu- blished by Professor Hirose of the Silk Institute of Tokyo, states that in Japan the spawn is preserved in natural grottoes by means of natural cold. These grottoes are neither more nor less than small caves hollowed out in the mountain, and in spring and summer there penetrates a current of cold air trough the fissures in the rock from underground. They construct in these grottoes the store-houses for the reception of the spawn to be preserved. In this way it is also defended from the evil effects of the dampness of the climate during the period of hibernation. This applies not only to the two-season varieties which are cultivated in March for the first rearings, and in July for the second, but also to the annual stock cultivated respec- tively in Spring, Summer, and autumn. - * Sometimes, instead of in a grotto, the current of cold air is found at the surface on a mountain side and in this case an enclosure is built with double walls to insure its protection from solar heat. Over this the store-room is situated; it consists of a single chamber where the spawn in suitable boxes is placed on gratings. - It is stored with safety in such premises until towards the middle of August, as there the temperature in summer does not exceed 8 degrees centigrade. 864 The only thing to guard against is excessive humidity which is injurious to the spawn even when this is enclosed in boxes. At the present day there exist in Japan at least 120 of these store houses, built either in grottoes or over wells. From all the foregoing particulars it is evident that: The application of cold in the culture of silk has not yet found prac- tical scope, while in the rearing of silk-worms it has been of great use, especially in the preservation of spawn in winter and spring, as by its means the development of the embryo can be regulated as desired, and consequently that of the silk-worms, without their suffering injury during the period of vitality within the egg; and anyone who is familiar with the industry of silk-worm, rearing will at once recognise that this application alone is sufficient to render valuable the principle of refrigeration. Cold has been rightly called 'the mighty checks. * 865 The Application of Mechanical Refrigeration $. to Blast Furnaces. By Oberingenieur R. C. A. Banfield, Wiesbaden. On the occasion of the annual meeting of the American Iron and Steel Institute in New York in October 1904, the American engineer James Gayley delivered his now famous dissertation on the advantages of dry blast, which he had applied to a blast furnace of the Carnegie Steel Company, at Pittsburg. Naturally the publication attracted very great attention, for it was claimed that the new process produced 25°io more pig iron and at the same time consumed 20°lo less coke, and the uniform quality of the product was also highly praised. It is a remarkable fact that even to-day, the views of experts as to the advantages of this process vary very greatly, and there are but few furnaces that have installed this very expensive air drying apparatus. This can only be explained by the fact that the problem is by no means a simple one, but is influenced by a number of factors; clear explanations of which following the manifold endeavours of practical experienced and scientifically instructed technicians are still wanting. The author cannot enter into these differences of opinion, since they embrace foundry technics; the following deals with the cold-technical side of blast air drying. The fairly large quantity of literature enables anyone interested in the matter to study the question more deeply. I. Means for drying the air. The question of the most advantageous means for drying such large quantities of air — 50,000 to 100,000 cu. m. of air per hour for one blast furnace — leads to the examination of two long known methods: the extraction of the moisture by absorption and the precipitation of the water content by cooling the air to below its dew point. - For drying the quantities of air just mentioned, which may have an initial temperature of 25°C and 80% saturation, down to about 3.4 kg water per cubic metre, 750 to 1500 kg. of water must be extracted per hour, so that we have to deal with very considerable quantities of water. 55 866 a) Sep a r a ting the mo is tu re by me a ns of a b so rp ti on. From somewhat scarce data in the technical literature it appears that the firm Daubiné and Roy in Lorraine made considerable use of chloride of calcium, which when freed from water through evaporation by heat was rendered suitable for being used afresh. Unfortunately there are no data as to the extent of the water absorption before reconcentration became necessary, nor is it stated whether the absorption was continued only until monohydrates were formed, or also until the formation of byhydrates. The cost of the process is stated at 65 pfennig per ton of pig iron, as compared with 1:50 marks for the Gayley process. The author knows of no further particulars, and it is very probable that the application of the process on a large scale did not prove satisfactory. - à) Pre c ip it a ti on of the mo is tur e by co o 1 in g the air. This method has long been well known to refrigerating engineers, for it is used in the preservation of food to a very great extent and in the most various ways. In a suitable cooler the air is reduced below the dew-point; the superfluous moisture is deposited on the surfaces and the air leaves the cooling machine at a low temperature almost completely dried. As long as the air keeps the temperature it had on leaving the cooler its humidity remains constant, which is a matter of considerable importance for the uniformity of its condition; variations of the condition may therefore be easily avoided. If we use 2 dry & coolers and do not work with too low back pressures, a part of the separated moisture is deposited as such on the cold surfaces and can be drained off without difficulty, while the rest turns to snow and must be specially removed from time to time, in order that the heat transmission may not be too much decreased. In wet & coolers the separated moisture is taken up by the non congealable solution; this is thereby diluted and must be brought up to the requisite degree of concentration either through evaporation or by adding more salt. I do not discuss the advantages and disadvantages of the 'dryx and ºwetº coolers here; dry blast installations have without exception been on the former plan from fear lest in making use of 2 wet coolers, salt water in the form of fine mist might be carried along with the air and thereby completely defeat the whole object of the cooling. The quantity of heat that must be removed from it in drying the air by cooling it from 25°C initial temperature and 80°ſo saturation to 5" is: 1. actual temperature decrease: 30° X 0.31 Cal. . = 9.3 Cal. 2. drying: (0.8 × 22:9 – 3:4) × 0.6 . . . . . . . . . . = 9.0 × 3. ice formation, supposing half the deposit to be ice, - 15 × 0.1 × 0.5 . . . . . . . . . . . . . . . . . = 0.75 × Total per cubic metre . . 19:05 Cal. or in round numbers 19 calories, which have actually to be extracted from the air. 867 To this must be added the following losses, calculated per cub. metre hour: Radiation into the cooling chamber . . . . . . . . 03 Cal. Heat equivalent of blower work . . . . . . . . 03 * Losses through imperfect insulation of apparatus and Conduits . . . . . sº . . . . . 0-1 > Total heat removed . . . 19.7 Cal.-cub. m. For every 100,000 cubic metres therefore in all about 2 million calories must be extracted. l In Fig. 1 the ordinates show the amounts of heat that must be extracted from a cubic metre of air of any degree of humility if cooled to — 5° C. At this temperature the moisture content only amounts to 34 grammes per cubic metre so that further cooling would but slightly lower the humidity and therefore to undertake it is not practicable. &iq. M. Y - (5 Getº. (by Q º ſº tº soilſeoia Qtowawa § "U &ſºſanq. *; ; tº .# -5 . s: -5 30° * -5 : .40&?. It is necessary in the initial plans for large cooling and drying plants of this kind to decide first whether the cost of an installation of large capacity shall be kept low, or whether on the contrary economy in its operation shall be provided for in ample cooling surfaces. In this respect an American and a German equipment will be hereafter compared. II. Air drying by direct use of waste heat. The considerable amount of waste heat from most blast furnaces leads to the idea of directly applying the same in a refrigeration machine for air drying, say in an ammonia absorption machine. This idea may be justi- fiable to a certain extent where according to the old method of procedure the top gases are not completely utilized. It might be found that works 55 % 868 conducted on modern lines (and only such will consider the advantages of blast drying) are also careful to make use of all gas produced, in motor driving, be it in steam or in large gas engines. Exhaust steam leaving the cylinders at or above the atmospheric pressure as well as the gases exhausted from gas engines afford a regular source of heat, which if of a sufficiently high temperature will readily justify calculations as to their use in absorption machines. In each individual case, a careful test must be made. Regarding the waste heat from gas engines, however, one soon finds, even in the largest plants, that the heat of the exhaust gases is far too little for the production of the large amount of refrigeration required for air drying, and that on closer examination various difficulties in construction arise which can hardly be overcome otherwise than by erecting a number of comparatively small absorption machines. For an examination concerning the heating of steam or ammonia boilers by means of exhaust gases from gas engines let us suppose: Volumes of the waste gases from the cylinders of a gas engine: 11,000 m3; specific heat of the waste gases 0.3 Cal.; temperature of the waste gases on leaving boilers 110° C. The mean difference of temperature for the waste gases in the boilers will then be, Supposing the gas to cool off about 425° between gas cylinder and boiler, (425–110) -- 2 = 157°; the heat given off hourly by the waste gases, 11.000X03 X 157=520,000 Calories, must be conducted through the heating surface of the boiler. If for the latter we take a coefficient of heat transmission of 23 Cal./hour/m”/1 °; then we get, as necessary boiler heating surface 520.000: (157X23)==about 150 m”. Of these 520,000 Cal. transferred to the strong ammonia solution, at most the half, i. e. 260,000 cal. hrs., can be effectively utilized in the brine cooler, for continuous working hardly more than 230,000 cal. hrs., so that, to attain two million cal. hrs. in the brine the waste gases of nine gas engines would be needed. So far as our knowledge goes, ammonia distillation through so great an amount of heating surface has never yet been undertaken. For safe, continuous operation it would be better to lead the waste gases through a clean steam boiler and to utilize the heat of the steam from this in a row of ammonia distillers; of course the refrigerating plant will be dearer in this case by the cost of the 1400 m” steam boiler and the piping and chimney. III. Air drying by mechanically actuated refrigerating machines. These may be actuated by steam or gas, and, inasmuch as the air is cooled through a considerable temperature range, the refrigerant is circulated through separate coils arranged one above another, which in turn serve separate. compressors, or opposite ends of the same compressors. The employement of four consecutive brine coolers admits of using a number of smaller com- pressors and motors, as against effecting the entire refrigeration with a single large cooler operated under the back pressure due to the lowest temperature employed. - -- 869 Examples of me th o ds for a i r dry i ng with co 1 d. Gewerkschaft Illinois Steel Co., g r South Chicago, -ºº: Povº orks, Illinois aiser", Cardiff Bruckhausen Cubic metres air cooled per hour 153,000 90.000 102.000 Number of Ammonia compressors 4 2 4 Compressor dimensions, diameter of cy- linder X piston stroke 570 × 914 mm 560 × 920 mm 558 × 915 mm - - g Gesellsch. Linde, Sterne & Co., Makers of the compressors Wilter Company Wiesbaden Glasgow Rev. per minute. 60 85 55 Piston displacement of a cylinder cubic metre hours 1,620 2,200 1,420 - e - * * - – 2:29 – 10.80 Evaporating temperature in refrigerator . (–200) — 15'50 – 18-60 — 250 Liquefying temperature in condenser . (+25°) + 32-20 + 24*70 Compressor h. p. ca. 283 450 ca. 248 Temperature of the returning brine | — 6'79 + 11.8% — 15'50 x. i Temperature of the brine on leaving . : — 14:00 — 13:30 – 20:00 Quantity of brine circulating litre hours 522.000 94.600 --- Specific heat of the brine per litre 0-84 0-94 - Calories extracted from the brine per hour . . . . (3,200,000?) 2,232.00 - Cubic metres of air passing cooler per hour . . sºmsºmº. 175.000 tº- Temperature of the air entering + 23:20 + 1870 + 6'70 Moisture in air entering. Gramme-cub. metres 19-4 9:6 7:0 Temperature of the air leaving . . . . — 2'80 – 6:20 – 6:00 Calories taken from the air per cubic - metre . tº g º a 16-9 12' 16 º Calories taken from the blast ** 2,130,000 * Supplementary water for ammonia con- denser, cubic metre hours wº 30 *º Temperature of water circulating to the condenser . . . . . . tº ſº tº * 27-10 * Temperature of the cool (supplementary) --- Water . . . . . . . . . . * 16' 6 sº 870 The following comparison affords an insight into the dry blast plants of the Illinois Steel Company at South Chicago, Ill., and that recently put into operation at the extensive central gas plant of the Thyssen 2 Gewerk- schaft Deutscher Kaisers at Bruckhausen near Duisburg (Niederrhein). Re- frigerating engineers can readily distinguish the difference between American and German methods in the data given. Some data are also given on blast- drying at Dowlais Steel Works, Cardiff, Wales. If one forms the theoretical working effect for the circular process of the ammonia Tu : (To–Tu) for the three plants, one finds (with Bruck- hausen the average of the four evaporating temperatures at –11-89), at the liquefying temperatures given: Illinois Bruckhausen Cardiff Tu: (To-Tu) . . . . . . . 562 6'11 4-96 And for 25” liquefying in all - CaSeS . . . . 5-62 7:32 4-96 Even theoretically the amounts of work necessary for the same refrigerating effect stand in this proportion to one another and under the supposition (unfavourable for the Linde plant) that the mechanical effect is the same for all three plants (this is not actually the case, because the low evapora- tion temperatures have an unfavourable effect upon it), then at 25° liquefying temperature the amount of work expended is about: Illinois Bruckhausen Cardiff (Vilter) (ſ_inde) (Sterne) 500 h. p. 385 h. p. 562 h. p. Then for 1 million cal. hours at the evaporation temperatures menti- oned and for +25° C liquefying temperature, the driving power to be employed for the compressors is about: Illinois Bruckhausen Cardiff (Vilter) (Linde) (Sterne & Co.) & 450 h. p. 345 h. p. 505 h. p. A comparison of these data for power expenditure leaves the American results far behind economically. The difference of temperature between evaporating ammonia (medium) and cooled air, amounts at Bruckhausen to 5.69 and at So. Chicago to about 19%; it will be remembered that over there they took pains to reduce the cost of the cooling plant and could not have been taken by surprise by the large temperature range. Erection of the air cooler. As already stated only tubular coolers of the 2 dry system « with Salt brine circulation are used here. In America and at Cardiff these consist of a number of stands of 2 inch wrought iron gas pipes; each group is erected in a high room, and the air to be dried passes upwards over the tubes. Simultaneously the thawing of the deposited snow takes place on one or two groups; the salt brine is drawn off into a cistern and the air cooler is then irrigated with warm water. When the thawing is complete the conduits are again filled with the cold brine and reconnected with the refrigerator. Such thawing process lasts about three hours; the cold stored up in the snow is lost so far as concerns the cooling of the air. At Bruckhausen the air cooler is arranged in another manner. The necessary refrigerating surface is contained in a four storied building, and consists of rib-tubing through which the cold brine flows. The air passes, in the opposite direction to the brine along the tubing and passes all four stories in succession. It is thus made to pass over a great distance – about 100 m. – and at the same time the quantity of circulating air and salt water is reduced to the smallest possible. This also becomes noticeable in measuring the brine pumped, the air circulated and the pressure necessary for driving the brine and air. Thus, for example, the power used at So. Chicago for circulating the brine (272 cub. m. hours against 77 atmosph. pressure) is about 95 h.p., but at Bruckhausen (94.6 cub. m. hours against 1 atmosph. pressure) it is only about 5 h. p. At Cardiff the blast pressure behind the fan amounts to 88 mm. water column, while at Bruckhausen, with a circulation of 90,000 cub. m. hours, it only amounts to 18 mm, and for 180,000 cub. m. hours 32 mm. water column. At the latter installation the thawing is effected in the most simple and effective manner, by simultaneous reversing of the direction of wind and brine, so that the whole heat of fusion of the snow is made use of for the cooling of the air and no part of air cooler is put out of action. At a trial for the simultaneous thawing of the entire cooler when coated with a five days accumulation of ", of ice two hours were required for its removal and the temperature of the out-flowing cold air did not rise above freezing point. Usually, however, only 's of the rib-tubing is thawed at a time, in which case the temperature of the out-flowing air rises about 1°/sº above that in ordinary working. The foregoing information has no claim to be considered an exhaustive treatment of this interesting application of refrigeration, it rather forms an addition to the detailed and meritorious articles by J. Bartel, James Gayley, Ch. Tellier and M. Boudouard published by the First International Congress of Refrigeration, Paris (vol. 3, pp. 190, 199, 223 and 237). The practical results of the operation of the Thyssen plant at Bruckhausen are not yet safely determined, as the plant was but lately started. The great double ammonia compressor at Bruckhausen is shown below. -87.2 Shaft Sinking by freezing process. By Engineer Franz Drobniak, Mine Director. The opening up of a new terrain, and the sinking of shafts are among the most difficult tasks of a miner. The obstacles he has to overcome are manifold, and the presence of water and quicksand which in earlier ages often made the work quite impossible, still necessitate much labour and expense. The upper strata found in the mountains of the later geological period, which cover the mineral deposits (coal, ore or salt) are mostly aquiferous and loose. The minerals are rarely discovered near the surface, and the in- creasing demands of the industries for these minerals necessitate their being brought up from considerable depths under great difficulties and at enor- mous cost. The cover generally contains larger or smaller quantities of ground water which often is so plentiful that, to sink a shaft without special appliances seems utterly impossible. Before shaft-sinking had attained its present state of perfection it was often impossible to mine the treasures of the earth, and the most promising territories had to be abandoned. This has happened in Germany, particularly in Aix-la-Chapelle, and the territory of the Ruhr, North of France, Belgium, England and also in Austria. Hand in hand with the development of mining technic, in the 19th cen- tury in particular, the shaft-sinking technic has become more and more per- fect. The inventions by K in d & Ch a u d r on, Thom so n, Triger and Hermann Friedrich Poets ch especially have reached such perfection. that the miner of to-day can, without boasting, say that nothing whatever can prevent him from successfully forcing his way into the treasure laden king- dom of the gnomes. Poet sch's ingenious discovery, the freezing process, treated in this paper is indisputably the pioneer of all modern methods. Before proceeding to the real nature of this process I will describe in a few words the difficulties met with when sinking a shaft in the ordinary way, in loose aquiferous strata: The alluvial and diluvial strata which as rule form the older cover mostly consist of humus, fine grained sand, poor clay S73 and broken stone mixed with grey, often fine grained sand the so-called quicksand. These loose strata and the ground-water form a semi-liquid mass, exercise such pressure on the timbering of the shaft as to imperil the work, or even make it quite impossible. This is particularly where quicksand is found. Prior to 1849, when K in d and Ch a u d r on introduced their system, and 1883, when Poets ch brought out his invention, the miner had but two methods of mastering quicksand viz: piling and shaft-sinking, both costly, protracted, and, what is more important, unreliable methods. The piling process requires the water being constantly pumped out during the work. The walls are secured with the requisite timbering hung to a crib by cramps and poles (prop-crib timbring). To keep out the semi-liquid mass props are driven into the sole and secured by timber as the earth is discharged. If the depth of the shaft is moderate, and the water not too powerful the shafting may be successful, but then only if the work is done very conscientiously and with the greatest care. On the other hand if the pressure of the sur- rounding earth is too great, if the pumps do not act properly, or the tim- bered cuttings give way, a catastrophe follows and the labour of months or even years is destroyed at one blow. The "sinking& process (walled or iron shafts) is connected, with just as much danger. The work is this process is begun above ground with discharging the water. The lining of masonry or iron erected on a care- fully anchored and Secured shoe at the pit-head is sunk, or forced down gradually as the earth is discharged by means of a borer with sack attached. As the shaft sinks the walling at the upper crib is continually supplemented till the shoe touches solid rock; in this manner the loose ground is supported. This work is by no means simple and often incurs the risk of all the work being destroyed. If, for example, during the shafting a hollow space forms on one side and increases with the excavating to such an extent that the overhanging mass suddenly collapses, the fall can be of such force as to destroy the walling no matter whether it be of iron or masonry. On the other hand, if the shaft be sunk without any mishap, yet the shoe can get set fast lopsided on a boulder or heap of fallen-in rock and necessitate con- tinuous boring which may cause the walling to warp or even split. Such an accident happened to the Hugo shaft near Holten. The shaft had been sunk 175 metres, was 6 metre in diameter and fitted with the best quality tubbings. Quite unexpectedly one Sunday a collapse took place, wrecked the tubbings, and destroyed the shaft. The above described methods are difficult and insecure yet neverthe- less adaptable, and hundreds of shafs sunk, often under the greatest diffi- culties, offer a splendid example of a miner's preseverance and energy. The failures are unfortunately also numerous, and Only too often a promi- sing and growing mining enterprise is ruined. Interesting examples of both perseverance and the constant improve- ment in mining technic may be found in the three shafts of the Rhenish- Prussian mines near Homberg on the left bank of the Rhine. The first shaft — inside diameter 7.75 metres — was commenced in 1857 yet, only after twenty years laborious work were the coal layers struck with a diameter of 2.68 metres. This work consumed millions of marks. The second shaft — diameter 989 metres — was begun in 1878 and finished seven years later, whereas the third commenced in 1891 took but three years to com- plete thanks to the experience gained but unfortunately very dearly paid for in the first two shafts. The top layers in this case were only 103 metres thick. It is obvious that after such experience the most daring speculator would shrink back from the dangers that may await him in new, unexplored and unwatered terrains. The inventions, in mining technic during the last few decades, which enabled a successful struggle against natural obstacles have called forth an unprecedented progress in mining during the last few years, in Westphalia, France and Belgium particularly. One of the latest and most important inventions is Friedrich Hermann Poetsch's freezing process which he successfully employed for the first time in 1883 when sinking the pumping shaft of the brown-coal pit Archibald & in the mining districts Aschersleben. Poets ch's process is, strictly speaking, not a new invention for the use of cold in mining was known long before his time; in Siberia, for in- stance, shafts have been sunk is this manner for years. The miners take advantage of the naturally cold climate, excavate to the water level, leave the sole to freeze, then excavate farther leaving each cutting to freeze, thus being able to sink shafts up to 24 metres deep. As early as 1862 an English contractor sunk a small shaft in Wales by means of artificial freezing, he used worm pipes and did the work piece by piece. This was, however, as a last resource and done by way of trial. Mining engineer Poetsch really was the first to employ the freezing process rationally and correctly in mining. His name therefore, is justly applied to this invention. Although this process has scarcely been known a quarter of a century, yet it has already gained a well deserved place of honour in mining technic. The great number of shafts successfully sunk in Germany, France, Belgium, - England and America, despite serious difficulties in the conditions of the ground, offer indisputable proof of the great practical value the invention. Owing to the extremely favourable condition of the mineral deposits in Austria this process was employed but once many years ago when the Venus shaft at Brüx was sunk, and then more recently, for two shafts in 875 Galicia, by the Brzeszcze coal mining company. The result in this latter case was particularly successful. The above company is working the seams of the southern wing of the great Moravian-Silesian-Polish coal field close to the borders of Upper Silesia on the banks of the Vistula in the parish of Brzeszcze 9 km south of Oświęcim. - The borings show not only rich veins of coal but also the presence of large layers of quick-sand which in the alluvial cap-rocks is as much as 30 metres thick and immediately above the green Sandy tertiary marl. The powerfull water-feeders that were almost sure to be met with, the unusual thickness of the quick-sand lode and large boulders besides soft sandy marl led to the adoption of the freezing process. The work has been entrusted to the well-known firm »Eismaschinen- und internationale Tiefbaugesellschaft von Gebhardt und Ko engº. Poet sch's freezing process, as is doubtless well known, consists of transforming the aquiferous loose ground temporarily into a firm mass by means of artificial refrigeration and enable the sole, protected by the frozen wall, to be mined without first pumping the water. This is done by a number of holes bored concentrically round the saft to be sunk, but beyond the intended diameter, until solid rock is struck. Conduit and freezing pipes are placed in the holes, and an incongealable Solution of salt, cooled in a refrigerating plant, continnously passed through them. By this circulation the ground around the bore-hole is cooled to such an extent that a frozen mass extending to the solid rock is formed round each hole. The distance between the holes being so chosen that the frozen mass around each meets, a compact wall surrounds the shaft strong enough to resist the pressure of the water and the overlapping rock. Thus protected, the work proceeds in the usual manner with the help of spiles, pickaxes, and blasting without pumping out water. This hard frozen wall is like concrete; it affords abso- lute safety for frozen sand has an enormous force of resistance. Trials show the force of resistance of the frozen sand at 12% below freezing point to be about 140 kilograms, at 15° some 160–170, and at 20° even 190–200 kilograms per square metre, considerably surpassing the compactness of sand stone. The air-shaft was first taken in hand with an inner diameter of 4 metres. The walls 90 centimetres thick and the isolating bed between the wall and the face 10 centimetres thick gave the shaft a diameter of 6 metres. The 24 bore-holes were 80–90 centimetres apart and in a circle of 7 metres in diameter. For mounting the refrigerating plant a pit 8 metres in diameter and 5.5 metres deep, was sunk to the surface of the water, and lined with a wall of 60 centimetres. An engine house and a derrick were elected over the pit in such a manner that all the holes could be bored from it. The holes were made by water flush drilling partly by hand and partly by machine. The boring was carried out without any particular inter- ruption, only the large boulders in the quicksand caused some difficulty. Each hole was carefully tested to make sure of its verticality. As the firm coal stratum was found at about 40 metres below the surface, the holes were sunk 42 metres, and pipes 120 millimetres in diameter and 9 millimetres thick; the lowest pipes were provided with end plates. Conduit pipes 26 millimetres in diameter were set into the freezing pipes with the bottom end open and allowed to project 4–5 centimetres beyond the freezing pipes. The collecting pipe and the feeding ring were now placed on wooden trestles in the pit and connected with the pipes in the holes by joints in such a manner as to enable a sure and regular circulation of the solution of Salt in each hole. Valves were attached to each joint and the circulation could be cut off from any of the holes if necessary. During the progress of the work that took about 18 weeks altogether, the freezing-plant was constructed and mounted in sheds built close to the shaft. * Ammonia was used for the refrigerator, and a solution of chloride of magnesium (25–30%) as a medium. The freezing-plant consisted of a 70 HP driving engine, 2 compressors, 1 plunger condenser, 1 irregation condenser, 3 refrigerators, 1 cooling water pump, 1 lye-pump, and the necessary pipes, lubricators, oil-cups etc. The rings of the pit were connected with the freezing-plant by wroughtiron pipes of 81 mm diameter. The pipes and the refrigerators were carefully protected by insulators to prevent the cold from escaping. The course of the freezing process was as follows: The solution of chloride of magnesium, for simplicity sake called lye, cooled in the re- frigerator as much as from 18–229 becomes slightly warmer in the course of circulation and rises to 14–189, thus about 49 of cold is passed into the surrounding ground; this escape of cold is replaced in the refrigerators. The lye flows from the collecting pipe in the pit through the exhaust pipes into the freezing plant and runs into the first refrigerator where the first Cooling stage is passed through, it then passes into the Second and third refrigerators; now sufficiently cooled the lye passes through the pipes to the feeding-rings which force it into the holes. The lye is cooled in the refrigerators from 18–22°C by flowing over the worm-pipes filled with ammoniac gas. The pump, already referred to keeps the circulation upright. The ammoniac gas is condensed from 8 to 10 atmospheres in the two machines; the gas heated by the condensing passes an oil-separator and is then conducted to the irrigation condenser where it is slightly cooled by ſlowing water. The gas now flows through the winding-pipes of the plunger- 877 conderser where, under a pressure of 8–10 atmospherees it is cooled by the flowing water, from 12–18°C and is transformed into a liquid state. The liquified ammonia now flows through a condensing-tube 25 millimetres in diameter, passes a second oil-separator where any escaped refuse is depo- sited, and after passing through a regulating expansion valve enters the worm-pipes of the refrigerator. Owing to the sudden increase in volume the pressure sinks to 0.7–0.9 atmospheres the liquified ammonia resuming its gaseous state. Through this expansion there is so much latent heat that the tempe- rature of the ammoniac gas sinks to — 18 to 22°C. This cold now passes over to the lye flowing through the refrigerators. Aftor passing through the worm-pipes in all the refrigerators the ammoniac gas returns to the con- densers when the above described process is repeated. The refrigerators were started on July 2" 1904 and worked conti- nuously with only one or two short interruptions, for the purpose of changing small parts or packing the stuffing-boxes, till the 24* February 1905, the contract term for sinking the refrigerating section. During this work the loss of ammonia, owing to a leak in the stuffing- box, was replaced by one bottle of 27 litres, whereas 5150 kilo chloride of magnesium were necessary to replace the loss in the solution. Tho fill the machines and to start refrigerating 10 bottles each 27 litres compressed fluid ammonia at 7 atmospheres, and 18.786 kilos chloride of magnesium were used. The formation of a regular and thick coating of ice on the water in the pit and on the conduit pipes and joints showing that the ground was frozen and the frozen mass was complete, mining was commenced on the 21st September 1904. 80 days had, therefore, been required to congeale the aquiferous mass. To judge from the hardness of the ground too much precaution had been taken and the work could well have been begun without any difficulty at least two weeks sooner. Consequently under similar conditions the freezing period can be fixed at eight, or at the most nine weeks. To cool the condensed ammoniac gas about 400 litres of water per minute, at a temperature of from 12–14° were used. At the outsed the work was pushed forward the gelidity of the lye gradually increasing till about the 21* day after the commencement of the refrigeration-process the full temperature of 21° C was reached. During the whole period two con- densers were working. The ammonia and lye pipes, and the collecting and feeder rings gradually became covered with a crust of ice to such an extent that the pipes of 110 mm diameter at last measured 350 mm round the outside. The ice formed a good insulator against any escape of cold. - Shaft-sinking was begun on the morning of September 21st 1904. The water on the sole of the pit was frozen hard to the middle where the crust 878 * of ice was thin. First the ice, water and mud were removed and the sin- king then begun. The first strata of yellow sand of about 4 metres were not frezen, and the work merely consisted of digging. The lower the sin- sink got the sand was frozen harder and the soft core in the centre became smaller. Owing to the trestles for the feeding and collecting rings about 4 metres were first mined and enlarged downwards so that at about 6 metres the inside diameter measured 6 metres. This width was kept to the bottom. The yellow fine-grained sand was frozen hard, and formed firm but thin sheets of conchoidal fracture under the pick-axe. The white arenaceous quartz was frozen very hard indeed, owing to the great percentage of water, and was as hard as graywacke, and the pick-axes, irons and Sledgehammers had but little effect on it. The loamy layers were frozen hard, but offered less resistance, and broke off in large lumps of conchoidal fracture. The layers of broken stone were struck at 17 metres below the surface; the soft core which got smaller as the work proceeded disappeared entirely here. The broken stone was frozen into a gray, concrete-like mass and pick-axes and wedges were quite useless so that blasting had to be resorted to. For blasting uncongealable dynamite No. II and No. III were used ; the latter quality has been given up as it proved too weak. Pitching borers and hammers were used for boring; borers 3 metres long and weighing 10 kilos were used later. A concentrated solution of chloride of magnesium was poured into the blast hole, which considerably facilitated the boring. . At first the blasting was done only in the centre and 50 centimetres from the sides owing to the refrigerator pipes, but later the shot was placed close to the side thus Saving the proping of the sides; during this work it was seen that the frost prevented the sides from renting. At a depth of 28 metres gray, fatty marl was struck; here the ground was also frozen hard, and the water, in the numerous clefts that divided the marl into small cubes, was frozen to a white chalk-like ice. Here, although the work was a trifle easier, it was very slow, and blasting had to be resorted to. Forty and a half metres were sunk without intermission, and the base of the wall built in Sandy hard frozen marl. These 40.5 metres were com- pleted on the 28th November 1904. The sinking of 35 metres (the pit was 5.5 metres) took 62 days. If we calculate 27 shifts for Sundays, holidays and various interrup- tions when no work was done in the shaft, the work actually required 53 days, or 159 eight hour shifts, making a day's work O'66 metre — very little indeed considering that neither timbering nor pumping was ne- cessary. * During the sinking, the sides of the shafts were not timbered at all: every six metres holes were bored on the northern side and props were wegded in for the Sollar. Iron ladders, seven metres long, were used for the guide. Simple temporary woodwork was fastened along the ladders to prevent the miners from falling. The facings held extremely well and there 879 was absolutely no fear of a collapse. The large drift-blocks in the layers of broken stones were frozen to such an extent that a part of the wedged drift-block broke off during the blasting and wedging, the rest, however, remained in the wall-face. The ventilation consisting of wooden air-pipes fastened at the top of the boiler flue was extremely good ; it must be remarked here, that before the air-pipes were arranged, ... no ventilation whatever existed and even at a depth of ten metres the lamps would not burn and breathing was impossible. The temperature in the shaft was very agreeable; through the lamps and the human breath it rose, in the centre of the shaft from one to two degrees, and at the sides, about 5 to 6 de- grees below freezing point. When work was suspended, the temperature fell from 10 to 12 degrees C. The lower the work was brought, the sides, ladders and sollars became covered with snowy - white rime caused by the breath of the workers. The rime formed all sorts of fantastic figures on the wood-work and air-pipes. The snowy-white sides with the sparkling crystals, the fresh- air, the bright light of the open oil-lamps, the absolute dryness and safety of the place, gave the shaft a peculiar appearance. When the work was at rest the absolute silence reminded one more of a fairy grotto than the gloomy abode of miners where, behind the wall of scarcely a few metres thick, the deadliest enemy of the miner — the destructive water treache- rously lay in wait. During the whole of the time taken in sinking no di- sturbance of any importance took place. The material was raised by means of a steam windlass, in cask-shaped buckets holding 03 cubic metres. No guides were erected and the bucket hung quite free; the free and fairly smoth sides of the shafts made this possible. As a rule, eight sinkers and four truck-men worked on the sole, and four men were employed at the mouth. The work was done in 8 hours shifts. The wages per shift were: sinkers K 450, truck-men K 280, draw-men K 280–K 2–. Further each pair of workmen in the shift received about 6 litres of hot black coffee. The men worked exclusively in master-shifts, no agreement for piece-work was made. This must be considered a great mistake and one of the reasons of the tardiness of the work. The dynamite used was: No. I: 145 kilos; No. II: 400 kilos; No. III: 50 kilos, making a total of 595 kilos or 20.5 kilos per metre run of 29 metres in depth. For blasting, uncongealable dynamite from Nobel was used and for the fuse Bickford’s safety fuse with caps of 8 grammes. Bickford's fuse was used in preference to the electric as it allowed the firing of the shots to be regulated by using fuses of different lengths. The shots could be let off singly and thus reduce the shock te the sides and pipes. A point that caused a fair amount of trouble in the preliminary arrangements, was, if cement would bind firm enough for an absolutely water-tight wall at such a low temperate. Very little information could 880 be gained from similar work, as in the majority of cases tubbings were . preferred. In this piece of work it was decided to adopt masonry as tubbings are very expensive. The work, therefore, had to be done with the greatest precaution. First of all, a firm foundation to the wall had to be provided. This was done by digging into the grey fatty hard frozen marl at a depth of 4022 metres. At the foot the wall was 105 centimetres and in the middle 135 cms. After the foundation had been hewn out, the projecting end of the bore pipe was chiseled off, the pipe plugged and a layer of concrete, 30 centimetres thick, stamped on the bottom of the shaft at 40.5 metres. This was to prevent the lower lying ground from thawing or becoming Soft should the shaft be placed under water to warm it. As soon as this piece of work was finished the masonry work was begun. A wooden Crib 10 centimetres thick was lodged and the wall built udon it; the base of the wall was built on the bare rock, and between the wall and the face of the shaft 10 centimetres of water-tight clay was rammed in. For the masonry work Oppelner-Grundmann's rapid-setting cement was used. The cement which set in 30 minutes was mixed with well-dried sifted sola Sand in proportion 1:3. The bricks made of good ceinker were also thoroughly dried. The sand and the bricks were used when still slightly warm. For mixing the cement a solution of salt of from 10–12% Bé, about 300 grammes salt to 1 Litre of water. For the lower part of the wall, Tonit, a mixture of CaCl, was used for salt and in the upper part calcined soda. The sand and cement were well mixed dry with shovels and lowered in buckets in a dry and luke-warm condition. They were mixed with a tepid Tonit solution immediately before use. As the wall got higher, an isolating bed of warm, thoroughly dried coal cinders and ashes 10 centi- metres thick, was stamped between the wall and the sides of the shafts. This was done every half metre. The wall was kept free from frost by usig warm cement, mortar, warm bricks, dipped into a tepid Tonit Solution just before use, and further by adding Tonit or soda. The temperature of the shaft while the masonry work was going on, was 1 to 2" C, 1 metre above the top of the wall 3–4° below freezing point, whereas in the centre of the shaft the temperature rose to 4° above freezing point. As soon as the base of the wall was completed and the guide bars set the wall plat- form was laid. The temperature taken beneath the platform gave the following results: Immediately after the bricklaying it was about 30 C, in 25 hours it rose to 70 and in another 24 hours to 12°C above freezing point. Only on the third day did the temperature begin to sink after the warmth developed during the setting process had expanded itself. To keep the new wall from freezing it was decided to constantly heat the space beneath the platform. This was done by filling the shaft 1.30 metres with water, and warming it from 20–25° C by steam pipes. As the wall incrensed a regular temperature of from 12–15°C was registered beneath 881 the platform. Further the steam rising from the water considerably aided the setting-process as it kept the walls damp. The guide and partition beams, and the iron Sollars were walled in as the work proceeded. At 30 metres a second wall foundation of 12 centimetres thick was hewn in the marl and lined like the lower one. To control the exactness of the wall a level, and a very practical invention, a spindle and a lath were employed. A wrought iron rod, 40 millimetre in diameter, pointed at the top end, was mounted on the platform, exactly in the centre of the shaft and vertical with the spindle, in such a manner that the point was exactly opposite the point of the plummet which was suspended on a wire rope from the crib by means of a trommel. On the spindle there was a slide- index moved by an adjusting screw. A wood lath weighted at one end and grooved to correspond to the spindle and provided with a clamp served as a control. The distance of the lath from the centre of the spindle corresponded exactly to the radius of the shaft, viz: 2 metres. The slide- index was always so placed that it stood exactly horizontal to a lath resting at one end on the index and the other on the top of the wall. The accuracy was always tested by a water-level. With the help of this lath the verticality of the wall could be easily and quickly controlled and the antefix always set with accuracy. The verticality and central point were tested twice during each shift, consequently the plummet was not lowered oftener, and the disagreeable and unreliable control by means of plumb-line, which wasted much time, was avoided. The bottom end of the spindle was fastened to the platform while the upper part was fastened by two nails driven into a prop let into the sides of the shaft. This arrangement proved a great success. The bricklaying was very agreeable and exact because the work procceded slowly and cautiously but without any interruption and unmolested by dripping water. The walling was commenced on the evening of the 29th November 1904 at the depth of 40.22 metres and finished at a depth of 4.5 metres on the 14th January 1905, 43 days all together; the hewing out of the centre base and the breaking off of the breast-work in the upper shaft is included. The slow progress of 0.8 metres in 24 hours may be explained, on the one hand, by the perfect accuracy with which the work was done, and on the other hand, the drying of the material and the mixing of the Tonit solution. The insulating with dry ashes took very much time which was lengthened by the severe winter. The wall throughout was two bricks thick and the isolating bed 10–20 centi- metres. As the walling proceeded the joints were flushed, the traverses, ladders and Sollars were set. The finished wall makes a very good impres- sion, it is perfectly water-tight, clean and faultlessly constructed. In the course of the masonry work the following surprising event took place: On the morning of the 18th December when the platform was about 11 metres above the sole, the water beneath the platform began to rise at the rate of 6 mm per minute which equalled a flow of 75 litres per 56 882 minute. This unexpected incident led to the surmise of an irruption behind the frozen shaft and caused great anxiety. Arrangements were made at once to bale out the water by means of buckets. After 24 hours of indefatigable and exciting work the shaft was emptied and the sole examined. It was discoved that the water rose from a disused bore in the middle of the Shaft through the layer of concrete. & In reality the water flowed through the cracks in the wooden plugs and round the pipe of the middle bore. The cause of the irruption was clearly the thawing of the ice in the bore-pipe which acted as a good con- ductor. The great pressure forced the water through the concrete-layer and filled the shaft. There being no vital danger two small pipes were cemented to the bore in order to give the water uniterrupted flow. A pulsometer was hung on a level with the head of the wall, and the shaft was flooded up to the platform; as the work propressed the water also increased. On the 14th January 1905 the headstone was laid, and a sinking-pump (Schwade's system) working 750 litres a minute was lowered to pump out the water. Early on the 23rd January, the last 10 metres beneath the frozen mass could already be sunk. After removing the layer of concrete 2 metres were sunk; the gray sandy marl was still frozen hard, and the work had to be done with a sledge-hammer, iron and pick axe. Owing to the danger of an irruption and a warping of the shaft, the cuttings were supported by pillars every two to three metres and underpinned 60 centimetres. The whole 10 metres were sunk in four divisions without timbering and at the depth of 51.40 metres the base proper of the large wall was started and the whole shaft provided with bricks and traverses. On the 16" March 1905 the completed shaft 514 metres deep was taken over and the further working conducted by the owners. The refrige- rators were stopped working and the pipes could be removed and the bores plugged with clay pellets and concrete. The pipes were removed by tha- wing each bore with steam; this work lasted from the 2* April till the 22nd April 1905. Although the ground was thoroughly thawed, the wall remained perfectly dry and firm and not a drop of water was noticed the whole depth. - The further sinking of the saft proceeded in the usual manner without timbering and was walled in cuttings of 5 to 7 metres in height. The one difficulty was the water flowing under great pressure from the centre bore; as the work increased a quantity of water gradually rose to 900 litres per minute. The sinking of the pump and the pulsometer greatly impeded the work, nevertheless the shaft was sunk 110 metres — at which depth the air shaft was started — without any accident. The facings consisting mostly of moderately firm sandstone were lined with a wall 60 centimetres thick. . The winding-shaft constructed at a running distance of 58 metres from the air-shaft has also been sunk by the freezing process, because the testing 883 bore showed the same stratification as the air-shaft. The experience gained, when sinking this latter shaft was made use of. The sinking and walling of the shaft was carried out by the owners themselves, and the firm, before mentioned, only sunk the refrigerating plant 36 metres. Thé freezing plant was left in its original position and only the lye pipes lengthened. The shaft was to have an inner width of 5 metres, the diameter of the ground to be frozen correspondingly enlarged to 83 metres, and the number of bores increased to 28. In general the work was analagous to that of the air-shaft but on grounds of the experience gained, far better results were obtained. The erection of the pit 9.8 metres wide, and 5 metres in depth and the considerably larger derrick and drawing frame lasted from 15th May till 26* June 1905 (40 days). The bores were commenced on 27th June with a punch-borer and already finished on the 24th July; consequently the 27 bores (the test-bore above referred to could be used as a freezing bore) together 837 metres required scarcely 22 days; this equals a work of 38 metres daily. The mounting of the collecting ring and the feeder and the connecting of them with the plant lasted from the 25th July to the 10” August – scarcely two weeks so that the refrigerators could start working on the latter date. * . . . . . . The freezing process suffered no interruption whatever, but on the con- trary, time was saved. Whereas 80 days were required for congealing the air-shaft, the hoisting-shaft, in spite of the greater diameter, was commenced on the 2* October, that is after 52 days. Seven metres were sunk imme- diately in profile and at 10 metres blasting was resorted to. The centre of the shaft was not frozen and thm soft core varied in diameter from 4 to 6 metres; this considerably facilitated the sinking as only the sides required blasting. Even the layers of broken stone showed a soft core of 2 to 3 metres thick and this was easily removed by shovelling. Thirty-six metres were sunk in one run and the base of the wall laid. The sinking of 31 metres (excluding the 5 metres of the pit) lasted from the 2" October to 4th November, no work was done on Sundays and holidays, which equals 1-11 metres sunk in 24 hours. The workmen were engaged by piece work which amounted to K 150 – per metre-run of shaft sunk including the erection of the soilar. The hewing for the base of the wall took 4 days and the masonry- work was begun without loss of time. The same precautionary measures as adopted in the air-shaft were taken in this case. Calcined soda was used instead of Tonit as it is considerably cheaper and answers the purpose equally well. Jº The bricklayers were also engaged by piece-work and paid Kr. 110– • per metre run of buil wall including the trimming of the platform and 56% 884 setting the temporary shaft-timbers. Not to delay the masonry work and to set the traverses as exact as possible shaft-timbers were temporarily placed in the open holes. The shaft was only fitted out and flushed as soon as the refrigerating process was finished. For blasting uncongealable dynamite N* I and II were employed with an electric time-fuse which could be regulated by placing pieces of Bickford's match-cord of various length. This kind of fuse is preferable to Bickford's as it not only saves time but is safer. As only the facings were blasted 86.11 kg of dynamite was used, this equals 57 kg per metre run. No accident nor interruption whatevcr took place the whole time. The walling of the shaft 5 metres wide, 31 metres deep lasted till the 7" of December, that is 23 days and equaled 1:34 metres daily. The further sinking was done in breaks of 1.5 to 2 metres; as carbonated sand-stone was struck at 36 metres the refrigerators were stopped on the 17* December, the ground thawed and the freezing pipes removed. The second wall foundations was laid at 35.80 metres in the carbonated sand- stone, the section of the shaft fiushed, cleaned and fitted with traverses, sollars and ladders. The sinking proceeded normally in breaks of from 5 to 7 metres without timbering. The water which rose at about 250 litres a minute was raised by a sinking pump (Schwade system). The amount of work done in month varied between 10 and 14 metres of shaft sunk, walled and fitted out. The debris was raised by means of a small winch and buckets. The frozen walls of the shaft were at first perfectly dry and water was nowhere visible. But two months later however, after the frozen mass had thoroughly thawed thin sprays of water suddenly appeared in various parts of the wall which showed no breaches whatever and the cement in perfect order and firmly set. The water rose from the joints which in all probability had not been sufficiently cemented. The water gradually decreased and very little trickled through one or two places and the sweat formed crusts and stalactites on the wall. The same observation had been made in the first shaft, but on a smaller scale, where the water left off entirely and the walls of the shaft are at present watertight. f The work can be looked upon as a great succes in every respect, considering the character of the ground and the great flow of water refri- gerating was the only suitable process, the more so as the work and the cost were satisfactory. As to the expenditure, experience showed, it was not much greater than by a successful sinking or piling process. On an average the cost per metre run including material and all the preliminary work, amounted to about Kr. 3600– for the air-shaft and about Kr. 3400– for the hoisting-shaft. The great advantage derived from this process is, that the shafts are substantially and safely built, 885 further, the surrounding terrain did not subside as was unavoidably the case with other sinking processes, and finally the fairly exact time can be determined for the completion of the work, this latter is of great importance for new undertakings. The principle which always had to be observed for mining unexplored terrain and under difficult conditions was always to give preference to such methods as offered the greatest assurance of success; in the foregoing example this principle has proved true. A difficult but profitable problem was happily solved thanks to the correct application of a suitable process which, it is to be hoped, will be the foundation stone of a flourishing and beneficial mining enterprise. - 886 Arrangement and Management of Open Air Artificial Ice Rinks. By Oberbaurat Ingenieur Eduard Engelmann. Artificial Ice Rinks. Through the advance in the development of skating which took place during the last third of the last century, and through the ever decreasing possibility of exercising this sport, so closely connected with social enter- tainment in town districts, the idea arose of producing cold by machinery and, placing this at the service of skating, of creating artificial ice rinks. In many large towns in every part of the world artificial ice-rinks were made; all, however — as enlargements of laboratory trials — in closed rooms, with artificially warmed air in the enclosed space (to avoid the formation of mists). The inventive activity of the constructors of these rinks aimed chiefly at the development of machine cold production and at the formation of the freezing plate. t The various known systems of cold production were applied with the best results; a large field of play for the inventive mind was offered by the problem of making an ice surface. Two types of plant for the production of the ice surface formed themselves, which had one requisite in common: a flat pan, in which the water was frozen. According to one type freezing pipes were laid over the floor of the pan at suitable distances apart; in the other, the cold production was laid beneath the floor of the pan, as a double floor, or as "man against man. laid Square pipes. Ice Making. In all artificial ice rinks a suitably high sheet of water was let into the pan and then frozen between and over the freezing pipes or the freezing floor. - The building up of the ice-surface by layer production — sprinkling in thin layers — contrary to the very common practice on natural rinks — , is not followed on artificial rinks. 887 Consumption of Cold. From a table given in part 5 of the year 1898 of the periodical for the whole cold industry the consumption of cold necessary for the production of one square metre per hour was, on the rink in Size in -- Sq. metres Calories Frankfurt am Main Exhibition put up in 1881 . . . 533 130 Munich 1892 . . . . . . . . . . . . . . . . . 640 110 Paris Póle Nord 1892 . . . . . . . . . . . . . 625 175 Paris Palais de glace 1893 . tº ºn a . . . . . . 900 180 Washington 1896 . . ſº g º a tº “. . . . . . 2200 115 direct evaporisation in * - cold basin Nürnberg 1896 . . . . . . . . . . . . . . . . 612 Summer 200 Nürnberg 1896 . . . . . . . . . . . . . . . . 612 winter 130 Brooklyn 1896 . . . . . . . . . . . . . . . . 1420 winter 100 Thus the average consumption of cold lies somewhere between 110 and 130 calories per square metre and hour. The time of using the ice rink lasted generally from October to April. Summer rinks — as was the case for instance in Paris – do not pay, as the number of visitors decreases in summer, while the caloric requirement and so, too, the working expenses rise to almost double. The cost of plant of the artificial rinks reaches very considerable sums, owing to the necessity of erecting luxuriously fitted halls, so that a profit can only be obtained with continual and large visitation, and by making use of the hall for other purposes, such as exhibitions, etc. Out of the skating Season. The sphere of use of hall rinks is limited to chief towns with large numbers of foreign visitors. Provincial towns can only take steps for building hall rinks, if such are connected with artificial ice making plants so that a complete use of the cold plant may be secured throughout the whole year. Open Air Artificial Ice Rinks. The great pleasure of movement in the open air, and further the consideration that with lower outside temperature and the ceasing of all necessity of warming the air of a room great saving of working costs was ensured led to the idea of making open air artificial ice rinks. Here the period of use is limited to the winter months — to periods of low day temperatures — so that a substitute for natural ice rinks is aimed at, a period of use of about 100 to 110 days being required. Consumption of Cold on Natural Ice Rinks. In the nineties preparatory work commenced at the Engelmann sport place, and first the consumption of cold in ice production and the preser- vation were subjected to examination. - . 888 The indifferent behaviour of the ice surface and the variously progressive process of freezing when water was sprinkled on to the ice surface, at the same outside temperatures, but with changed weather conditions, led to the recognition that the cause of this factor was the warmth streaming out of the room and warmth streaming on to the ice surface; exact experiments were, however, not carried out. The well known fact that on open flat vessels ice forms already at 3° C. — on clear nights, with decreasing temperature – further, that with clouded sky and thick mists, in spite of sinking temperature ice only forms at from —1"/," C. to —2° C., led to the recognition of the already evident fact that the moisture contained in the air was of great influence; for this, however, no regular laws could be distinguished. The number of calories used on the upper surface of the ice was therefore experimented on by melting trials with and without application of warmth protecting covers. Repeated experiments were also made on the thawing of the ice surface with strong warm draughts of air (Föhnwind). - With the patent wooden covers the calories required could be brought to 10 calories per square metre, with a medium day temperature of 40 C. Warm Föhn on unprotected ice surfaces at 10° C. required 40 to 60 calories. - w Rain, if the water was diligently removed from the upper ice surface, did not act more harmfully than Föhnwind. Further data concerning the caloric requirements were obtained during the ice production attained with different temperatures and weather conditions. On clear nights at — 4° C. a thickness of ice of 8 to 10 millimetres was obtained in six hours (theoretical caloric requirement per square metre about 125 to 155 per hour), while this result at the same outside temperature on cloudy nights sank to 2 to 3 millimetres (per square metre 30 to 50 calories per hour). The above observations as also finally the circumstance that with higher day temperatures (10°C. in the shade), clear sky and sinking tempe- rature the thawed ice water on the upper surface began to freeze (lively formation of ice crystals) at 6' C. even, led to the conclusion that with artificially cooled under surface the once formed open air -ice surface could be kept in condition with a far smaller caloric requirement than could ice surfaces in closed rooms. - Practical Freezing Trials. In order to obtain concrete data as to the caloric requirements of open air ice rinks, practical freezing trials were undertaken. Since the early nineties the Vienna representative of the firm L. A. Riedinger, at Augsburg, has been endeavouring, in a most thankworthy and self-sacrificing manner, and assisted by the author, to ascertain the cold requirements of open air ºwwow.yoßwę tę ºſówę pozwoqºqººccº wypºwą wowo wo 9 v.v og dan wongongood øog'24'oyd ſo ſwąwozºg ∞ √•�:øuțI ȚIN y (36;pøsn pio O 'canoſy 2 wą ewew eyoo ºſovooo—— '^^oy2ød.Cºcº eyooļo'yooop 6yo ezwopo2~ ·ſwyddwc224 oov ſyocſówyſwoºp wąſyoneøa22c9oqwa ſep2%ºyoo ow!? "poo º/,6v qwoyo ºyooļoccoyyoſoſ| (yoo96*Jyooºoºooºy!)«øya oyooZį, į,:gøçwø24„wę2c} øył wo eøen egoo ļo coyºoyoo oo6 gweº ww.z = yw ewo anoſ 22d woqongozd øog。 „w 2ød coyºoyoo offz�Ab§§ „w #ļoøywydyoyºq ºqoºyov: •- - -）sæ • -→ = --•– ·– pump $–$ $ ſ | | | | | | | | | Saſt watov OH−\---------- –- –|-• • OH- ----→ • → • • • • • • •--------------------- o-№----------------- „ſ“-TOE-- - - - - -------- ---- ol-1）----------T-T-T-T- ~º OH−ł!--- – –, –––---→ ---- ĒĢ ÈR) 2- | | | | | 4& j t iſ | | | | | | | Ścich cooſing towev |×|- *N----** --> • → • ） --- « : Sieve pot s m me • * * * * * * * * * * * * * * * * * * * * * * *.* * * * * * * * * * ‘….Tº…~~~~ it t it iſ ſiſ | | | | || | || ||| | | | | | ||||| ||||| ||||| * → • • •==<！--- •* ****** • *= * =：= * === ~ ~- - - - -） . ___ . ILLUSTRATION V. Consumption of cold at the Open Air Artificial Ice Rink. S-. " t .* Day: 12. - - "... - - 16. 17. 18. & Weather: º * - dull rain dull wind dull rain g & 8 } f 7 2.3.4tSG 4 O Zero line: - - - - Hour: JAL * * * G $ 40 JNſ 7. A * . . 4; & | H * it JV" it. (? vº. t{ * 8 ~44. 44 JAf *i G 47 t - f f * * * * * * Y-> / Comp, stopped , - ſ C. st. Comp. st. | & St. C. st. | - º St. - Comp. st. - C. * , | Comp. st. § **-----" * * ~ — H– *======= I I Compressor stopped 46000 182000'Cal. fºr- - *...*. - 142000 Cal. 38000 f A 228000 Cal. * 10000 Cal. s 152000 Cal. - º, 28000 114000 Cal. | | ---. rom Acc. rom Acc. ; — " . . . . - tºº-º-º-º-º-º-º-º-º-º-º: ººº- | | from Accum. from Acc. from Acc. from Acc. . ." • . from Accum. z \ . -- º * - - t- Day temperature { #iºd * === average temperature * - 10cold gradient ſ 46000 Cal. cold used over whole surface * -- * , - assrººm- . . . . ~ uals: * ... Oberbaurat Ing. E. Engelmann. IQIO. w \ ; : --------> & equals: 42, calories per m”, -------- Calories used cold gradient read off --- a Verage ºl. in 24 hºurs ever * - - - t the freezing bottom \ completed the whole freezing bottom of 1080 m2, - - sº - . . . . . g • .* .-- 889 rinks. Like the author, too, but separately und independently, he has also been conducting practical trials which dealt especially with the cold trans- mission of freezing pipes of various width, and laid at varying distances apart in a freezing plate constructed according to data furnished by the author. As at the time a rink of only 600 square metres was intended, an element of the distribution tube system — 160 such elements of 40 metres simple tube lengths were projected – was inserted in a freezing plate of about four square metres. * The plate was similarly formed and provided with the same kind of bed as was planned for the future open air ice rink. - The first illustration gives explanations of the trial. The chief result was the discovery that in the formation of the ice surface there was only a slight loss of cold. The Vienna Open Air Artificial Ice Rink. As a result of the experiments it was necessary to reckon with a cold consumption of from 120 to 150 calories per square metre, in order that within reasonable time, and at an outside temperature of 5" C., the ice surface might be made sufficiently thick. As it was clear, however, from the above mentioned melting experiments, that for the preservation of the ice surface a fraction (1/10 to */1s) of this value would suffice, the author decided upon a rink of 1080 square metres (30×35 metres), whose freezing system consisted of two independent halves. One half was to be filled and then this finished ice surface covered with the warmth protection covers while the second half of the rink was made. For economy in working the cold machine plant was SO chosen that it could preserve the whole 1080 square metres of ice surface when the average outside temperature was 5° C. At higher outside temperatures a part of the ice surface had to be covered with protecting covering, thus decreasing the free ice surface, that the increased requirements of this part might be met. As working reserve —- in case of temporary interruption, or Small repairs — an enlarged refrigerator reservoir was provided as cold accumulator. This accumulator with 50 m3 of brine at —100 C. to —12" C. will, if raised to 1" C., furnish the rink with about 500,000 calories, that is it will either completely replace the machine for several hours or increase its effect during higher outside temperature. With the working power in view (electric on account of the position of the rink amidst houses), economical reasons made it necessary to shut off the machine during hours when the price of the current was at its highest (between 4 and 7 p. m., when the greatest demands were made upon the electrical company's store). During these hours only the circulation pumps remained in Operation and the necessary cold was taken from the accumulator. 890 Financing the Vienna Open Air Rink. ~. * At last, in 1909, the plan that had been considered for the Vienna Open Air Rink since 1896, could be put into effect, since through the years of observation and experiment the conviction had been gained that the suppositions of the authorities on the subject of artificial ice rinks, as also of cold technicists regarding the consumption of cold, were not applicable to open air rinks, and that a suitably large ice rink could be worked with comparatively slight expence of power, and consequently, that the financial means at disposal would suffice for such a rink. The capital of 85.000 Kronen put in for the arrangement of the rink could, according to careful calculation, not only be paid interest on, with an annual turnover of 36,000 to 40,000 Kronen, but could also be amorti- sized in from 10 to 12 years, whereby the further circumstance that a well arranged natural ice rink was available and could be procured for a very moderate rent also told in favour of the undertaking. The starting capital of 85.000 Kronen was obtained by the issue of 350 share certificates at 200 Kronen and by the taking up of a cash advance of 10.000 Kronen. The publication tables (see illustration II) proved very effective in the financing action. These showed the number of days that could have been gained for skating during the foregoing winter, had a cold plant been available similar to that projected. - Great care was taken in drawing of these tables and only those day were reckoned, on which the noon temperature was but little above 59 C., whilst an average daily temperature of +5° C., was made the basis of the artificial ice rink project. Details of the Open Air Rink Plant. The general arrangement may be seen from illustrations III and IV. The machine plant executed by the Austrian representative of the firm L. A. Riedinger, Augsburg comprised: - I. The cold producing plant (carbonic acid compression system): a) the carbonic acid compressor, ô) the drizzle condenser with the plant for making use of the Snow, c) the cold water back cooling plant, d) the refrigerator. II. The cold distributing plant: a) the salt water circulation, b) the freezing bottom. The compressor produces 90,000 calories and is driven by a 30/45 H. P. electric motor by means of gearing. The drizzle condenser is of large dimensions, and has a second carbonic acid pre-cooler, which is built into a sunk concrete vessel; there the fresh brine is let in and the snow put in that has been cut up during 891 the skating. This making use of the snow (patent applied for) offers the great advantages that not only is the carrying away of the snow to a depôt, or to canals, avoided, but also that a very low carbonic acid tem- perature, and consequent increase of the effect of the machine, are obtained. The cool-water back cooling plant is formed above the drizzle con- denser as graduation work, with large cool-surface for the sake of saving cool-water. Part of the back cooled cool-water is conducted to the Snowpit, in order to melt the snow sufficiently rapidly. In this manner the whole water supply can be saved during skating. The graduation work works with water temperatures of from 70 to 90, the back cooling obtained amounts to from 2 to 3". In the snow-pit the water temperature is always a little above zero. The cool-water is led over the graduation work and the drizzle condenser by means of a circu- lation pump effecting 30,000 litres per hour. - The cool-water circulation pump is driven by gearing of the compressor. A second driving power for the pump is not provided as the circulation of the cool-water is stopped at the same time as the compressor. With suitably frost-proof placing of the circulation piping it becomes unnecessary to empty the piping every time the compressor is stopped. In long working pauses, especially when such are caused by the entry of severe and lasting frost weather, the piping is emptied. The refrigerator has an unusually large upper surface. It is built into the concrete cold accumulator vessel and provided with stirring works. The stirrers are driven by the gearing of the compressor, and thus stopped at the same time. A separate gear is not necessary for these stirrers because when the cold production ceases, and the cold is taken from the accumulator, the effect of the brine circulation is sufficiently powerful to replace that of the stirrers. The salt water distributing plant consists of the chief distributors, situated at the head of the rink to which 150 U-shaped bent cold tube systems are parallelly joined, and of the pumping plant with the circuit switch and the cold regulation apparatus within the machine house. The salt water pump, with effective 50,000 litres per hour, is double driven : normally it is driven by the compressor gearing; when the compressor is not working the pump is driven by a small 2"/3 h. p. electric motor in order to be able to draw the cold from the accumulator, even when the compressor is still. A circuit switch arrangement for the salt water circulation proved to be impossible according to the experiences made during the working of the artificial ice rink, as a means of preventing an uneven formation of ice close to the inflow and outflow of the refrigerant in the freezing bottom. This switch arrangement becomes useful when the previously determined cold gradient at the inflow and outflow of the salt water piping has taken place. The Switch arrangement is arranged as a by-pass. The practical application can be conducted by hand or automatically without disturbing the works. (Patent applied for.) If the switching is not effected an uneven formation of ice results near to the inflow of the refri- gerant, especially during higher outside temperature and the use of larger cold gradients. In spite of this turning of the direction of circulation a greater ice formation at the points of inflow and outflow, and so a higher effect of the cold on the ice surface is still noticeable. - This phenomenon may be counteracted by suitable procedure during renewal of the upper surface, but it is better counteracted by laying the distribution tubes deeper in the freezing bottom at the points of inflow and outflow than in their further course. - Then the greater thickness of material over the pipes offers greater resistance to the cold passing, the refrigerant has a weaker cooling effect On the upper Surface of the ice and the formation of ice made slower. (Patent applied for.) Measurement of the thickness of the ice which forms over the freezing bottom show, as in the sketch, that curve at which the cold tubes should be laid in order that evenness may be attained in the ice formation without special treatment of the points of inflow when the upper ice surface is renewed. The regulation of the cold gradient is effected by suitable adjustment of a valve which is built into the connecting tube of the main pipe for the cold conduction. The function of this valve makes it possible to partially or entirely shut off the cold reservoir from the circuit of the salt water, therefore any desired cold supply from the reservoir can be conducted into the salt water circulation, so that a definite cold gradient can be set. The Freezing Bottom. Following the experiences gained by practical freezing trials, and in working the local natural ice rinks, it was projected to form the ice surface by means of spray ice, contrary to the generally followed process of ice making at artificial ice rinks. The freezing of larger quantities of water, which exist between the pipes, is here avoided, and the passing of the cold to the upper surface of the ice is made more easy. - The freezing pipes were therefore embedded in ferro-concrete plates which rested free on the asphalt bed for the sake of easier expansion. This bed is of layers of material impervious to water, such as concrete and congerial bricks, which hinder the increasing floor moisture and also the penetration of the cold into the floor, and so lessen the loss of cold. The distribution of cold in such a freezing bottom is very even, the penetration of the cold to a certain depth in the bed produces greater stability of the 893 cold consumption in quick changes of the outside temperature — in a similar manner to lined clay ovens. w Power requirements for the whole plant. This amounts, inclusive of all pumps and stirrer driving ſmachinery, transmission losses, etc., to about 32 h.p. Cold Consumption of the Open Air Artificial Ice Rinks. Table V furnishes particulars on this matter. It gives a survey of the course of the curves of cold consumption as compared with those of the outside temperature. Further and more thorough observations are being made and will be separately explained. An experimental plant just made in Budapest for the purpose of making a large open air rink will also be made use of for these observations. This experimental plant will also serve to decide what losses of cold take place in the floor with various (moist or dry) flooring. The cost of working amounted in the first year, with about 119 days of working and an average of ten hours daily, 3500 Kronen at 16 Kronen per kilo-watt-hour of current and inclusive of cooling objects, oil, glycerine, and carbonic acid. - Experiences During Working. As is evident from the curve in illustration V, the changes in outside temperature must be followed in the production of cold, and in the setting of the cold gradient, only so far that during increasing tendency the cold transport be forced into the freezing bottom to create a store of cold, while during decreasing tendency — rapidly advancing — this cold transport be diminished, whereby the use of large cold gradients otherwise necessary is avoided, and an economical working and an ice surface that is always good are achieved. The existing cold machine plant suffices to overcome a maximum day temperature of 12", to maintain absolutely the ice surface during Föhnwind and rain weather, and after cessation of 'the rain to make it possible to re-open the rink in one or one and a half hours time. Powerful Sun rays could not be overcome by the cold circulation alone; the available Sun boards had to be resorted to for assistance. It seems doubtful, too, even when specially strong sources of cold are available, if such open air place could be kept in an evenly good condition when part of the rink is in the shade and part in the sun and strong cold transport is made use of. Advantages and Disadvantages of Open Air Artificial Ice Rinks. As advantages may be mentioned the cheapening of the plant and working expenses. Larger ice surfaces can be made and worked. The use of open air rinks offers the heightened pleasure of movement in the open air. S9 | Through the fine precipitations of moisture, that only form and freeze gradually, on account of the relatively slight difference between the temperatures of the outside air and the ice surfaces (59 outside air — 3" ice surface), the top surface of the ice is brought to that condition which may be observed on natural ice places after a sudden warm wind, and which is specially liked by skaters as, through the thin layer of frozen water, the ease of skating is increased. On artificial ice rinks in halls, the precipitation and freezing take place very quickly, in consequence of the great differences of temperature (15" in the hall, -8 to —10" on the ice surface) the ice surface gets a velvet-like covering of snow, which offers greater resistance to the skater than the water like coating on open air rinks. The disadvantages of the open air rink are: Non availability during rain ; necessity of warding off direct Sun-rays, or separate cold conduction for the sunny and shady parts — to admit of unequal cold supply. This increases the cost of open air rinks. Province of Application of the two Systems of Artificial Ice Rinks. Hall-rinks as ball and entertainment halls, in which skating can also be carried on, are suitable for large towns or for southern districts, where low temperatures for longer periods fail, or where rain periods set in at these times. Open air rinks as sport places, are suitable also for smaller towns and for districts with periods of low temperatures and little rain. The present publication of the development, arrangement, and working experiences since gained of open air artificial ice rinks, the completion of which provides a new field of action for the cold industry, may be a spur to lead the newly opened field to scientific and industrial elaboration, for the benefit of industry and as a blessing to those who need a recruiting of spent nerves by means of sensible sport and movement in the open air. The use of cold in the Manufacture of Explosives. By M. Ottendahl, Ingénieur, E. C. P. Paris. The use of cold in the manufacture of explosives is limited at present to the refrigeration of the acid mixture used in the manufacture of nitro- glycerine. As is well known, whatever the process used, the acid mixture is cooled during nitration by 3 coils for circulating water, and the temperature in the apparatus cannot exceed 27 to 30° C without danger. However, it happens quite often, in summer, that, the water used being already of a temperature of 17 or 20°C, Refrigeration becomes difficult, nitration conse- quently lasting a long time. This not only causes bad production, but also increases the danger. Factories situated in hot countries have therefore had to resort to artifical refrigeration of the water : but this simple means has been slow of adoption. The advantage to be derived from circulating a colder liquid in the coils than the water, taken directly from the river or the wells of the factory, is clear, making it possible, firstly, to increase the active capacity of the apparafus and omitting one or two of the three coils immersed in the acid mixture, the three refrigerating coils usually occupying about one third of the available space; and, Secondly, nitration would take place more rapidly and with less danger, because refrigeration could be accomplished more energetically in case of a rise in the temperature of the apparatus; finally, of course, less liquid is required at, say, 4 or 5° C, than water at 15 or 179 to obtain the same result. Another manufacture requiring the use of energetic refrigeration is that of dinitroglycerine, such as is prepared by Dr. Mikoloyack. This substance has the curious property of gelatinizing the gun cotton when cold, and up to 50% of its weight, without any intermediate solvent. Dinitro- glycerine may be prepared by pouring glycerine into nitric acid, free from nitrous vapours, and contained in a vessel Surrounded by a mixture of ice and salt, the acid being at the same time agitated by a brisk current of air. When this manufacture is further developed, there will certainly be oppor- tunities for perfecting the system of refrigeration. 896 We will give yet another instance where refrigeration will be applied, namely in the recovery of vapours of ether and alcohol in factories for smokeless powder or for celuloid, a process indicated by M. Georges Claude. Finally, we think that cold can be usefully applied in all recovery of acid vapours, in factories for nitrocellulose. In such manufacture acid vapours are given off during both soaking and drying, and these vapours, which would render the atmosphere of the workshops unendurable, and which represent a loss of acid, are removed by drawing them through draft funnels, or trough ducts to fans conveying them to the condensing towers. At the top of these towers water is distributed, which absorbes the acid vapours. It is necessary to circulate this water methodically over and over again, in order to finally obtain an acid registering at most 36° to 40° Beaumé, when condensing nitrous and nitric vapours, as in this case. In summer time ab- Sorbtion is very difficult, and it is necessary to increase the flow in the towers, involving a great deal of manipulation of the liquid, and giving a less concentrated acid. A better result could, we think, be obtained by refri- gerating these acid vapours in the towers, and thereby perhaps condensing a good quantity of the nitric acid which they contain, the rest of the vapours passing to sprinkling towers, where they are absorbed. In this way a more concentrated nitric acid would be obtainable at first hand, the value of which would be very much greater than that at 36°, usually obtained, and much less liquid would be required to circulate in the towers, in order to obtain the complete condensation of these acid vapours. 897 On Refrigerating Plants on Ships. By Heinrich Wagner, Professor at the Technical University of Vienna, Chief Engineer fo Naval Constructions. Keeping pace with the prodigious progreſs which has taken place in the field of naval constructions within the last few decenniums, it is also the interior organisation of ships which, thanks to the improvements made in technical science has been able to adopt itself more and more to the increasing exigencies of practical life. The results achieved by the refrigerating industry have enabled us to satisfy a number of requirements many of which have long been keenly felt, while others have but recently arisen. Thus, for instance, it has long been a long-cherished wish that the ship's company should have refreshing beverages and, in the case of long sea passages, also fresh provisions served to them in the place of the artificially preserved meat, vegetables etc. without having to take live stock on board which led to all sorts of nuisances. The refrigerating plants of to-day enable us not only to keep fresh the provisions Supplied for daily consumption, which cannot be otherwise kept fresh for any length of time, but they also enable us to render whole cargoes of fresh meat suitable for a transport of many months and thus to adapt the wealth of foreign cattle to the needs of the great centres of consumption. On ships of war in which it is unavoidable to accommodate the stores of ammunition near the always very hot engine and boiler rooms, it has been found indispensably necessary to place refrigerating plants inside the ammunition stores in order to prevent a decomposition of the powder and destructive vitiation of the ammunition. Temperatures of upwards of 25° C are no longer considered desiderable for the durability of the modern smokeless powders to avoid coming too near the limit of temperature at which decomposition is liable to take place. It will be easy to appreciate the significance of refrigerating plants for ammunition stores when I say by way of example that modern large battle-ships often carry for more than 200,000 kilograms of powder on board. The catastrophe on the armour-plated ship Jéna, which was attributed to the decomposition of the powder and which destroyed that powerful unit of the French fleet to such extent that it hat to be withdrawn from operative service, a vessel of a value of about 30,000,000 of Kronen, may be adduced as a further example. 57 898 The first refrigerating plants on ships scrved in the most primitive way to keep beverages and fresh provisions cool for the staff and the more distinguished passengers on board ship. They consisted of ice-boxes of comparatively modest dimensions and, if needed, of isolated rooms in which a certain quantity of ice could be stored. The high costs of this procedure and the necessity it involved of running into harbours with resources of ice, rendered very welcome the adoption of means which the progress made in refrigerating technics, placed at our disposal, of being able tho produce ice on board, even though in restricted quantities. From these little ice-producing machines a short step to the modern refrigerating plants in which the production of ice plays only a subordinate role the object of which being rather to reduce the temperature in the entire ship's hold, to the extent required by the exigency of the time being. Far be it from me to give a description of the different systems of refrigerating apparatuses with all the improvements they have undergone up to the present. This I must leave to more competent experts. I will merely point out such features as are peculiar to plants on board ships, as appear to be desirable and should be taken into consideration. As self-understood conditions we mey regard greatest efficacy together with least weight, least requirement of space and power, safety in working simplicity of construction, absence of pernicious influences on the air in the working-room through the escape of noxious gases (even though unintentional) such as ammonia, carbonic acid etc. The condensation of aqueous vapours ir the air of the ship's hold, which invariably contains a high degree of moisture shall not be performed in a manner injurious to health. - The refrigerators shall, if possible, be placed in rooms that do not require a special staff of attendants, but where the working can be attended to along with the other duties of the service. Long steam-conduits to the refrigerators, tending to heat the rooms they pass through, should be avoided as much as possible In the fulfilment of these chief conditions it is not only the construction of the refrigerators, but also the manner of isolating the refrigerating chambers that plays a great part. In the choice of the system of refrigerators regard must be had to the ship's not being, as a rule, of quite rigid Systems, as is the case with plants on land. The walls of normal screw-steamers are always in a state of vibration, besides which the ship always undergoes deformation in a high sea and this naturally re-acts prejudicially on the tightness of the conduits and escapes. The result of this is a certain difficulty in such systems as operate with gases injurious to respiration. We therefore find on ships, provided the size of the plant allows it, that such systems of refrigerators are preferred, which work only with com- pressed air, And the process will be found to be more advantageous in which the expanding air circulates in refrigerating tubes in a closed rotation, as compared with those systems in which the expanding air escapes freely 899 into the refrigerating chambers where it is sucked in again by the same chambers and compressed. The moisture of the air attaches itself, in the first-named system, in the form of snow to the refrigerating tubes and not to the walls and the objects deposited in the refrigerating chambers. With this system it is moreover possible to let the refrigerating con- duits travel a longer distance, thereby enabling the refrigerators to be placed at suitable distances away from the refrigerating chambers, whereas with the systems having a direkt expansion of air into the refrigerating chambers the machines must be established as near to them as possible. The disadvantage of long steam conduits the refrigerators, whereby the ship's hold becomes heated to an unpleasant degree, is obviated either by a superior isolation of such conduits or, in the most radical manner, by working the refrigerators by electricity. For larger plants the preference is given to those systems in which an independent cooling liquid, a solution of chloride of sodium, is cooled by means of the refrigerators and driven by the force of pumps through systems of circular closed tubes which in serpentine windings in the refri- gerating chambers present the necessary surface for cooling the interior air. - An important question is the manner of renewing the air inside the refrigerating chambers for the storage of provisions, which has of course to take place from time to time. As the temperatures in the provision stores should invariably be maintained somewhat below freezing-point, the renewing of the air by means of fresh outer air can usually be effected only periodically, when the stores are empty. The vitiated air must then be sucked up by means of ventilators and air from outboard introduced by means of special conduits. It is self-understood that such air conduits must be made capable of being shut off. The process of cooling the ammunition stores in modern plants is to affect a circulation of air by means of ventilators only inside the storage rooms and an air-cooling apparatus placed outside the storage room, or also in the normal way by fixing refrigerating serpentine tubes to the walls of the storage rooms. The air-coolers consist of an isolated box containing serpentine tubes within which the cooling fluid circulates. Over these serpentine tubes the air sucked up by the ventilators out of the ammunition stores is left to Sweep and is then again pressed into the storage rooms. The advantage of this arrangement is a good circulation of air in the storage rooms, moreover, the air being kept dry, none but the air lost trough the permeableness of the conduits having to be replaced, so that very little moist air can enter. As the temperatures in the ammu- nition stores have not to be kept lower then 25° C, it will be sufficient, when the temperature of the outher air is lower, to introduce it direct into the storage rooms by means of ventilators without the employment of re- frigerating apparatuses, for which reason the air coolers should be made capable of being put out of circuit. 5 7 ׺ 900 To avoid the frequent opening of the refrigerating chambers, an ice generator is usually connected with the refrigerating plant in order to produce the artificial ice needful for the requirements of the ice-boxes in the pan- tries of the cook. Refrigerating serpentine tubes are moreover regulary inserted in the drinking-water tanks of the crew on board ship to enable the drinking water to be cooled to a temperature of about 9°C. The idea has moreover been repeatedly considered, whether it would not be possible so to combine the steam-heating plants of vessels with the cooling plants, as to enable the same conduit to effect, according to requirement, either the heating or the cooling of the living-rooms. No intimation of a satisfactory solution of this question has reached me as yet. There is something ex- tremely attractive in this question, seeing that there already exists a widely ramified net of tubing for heating by steam on board ships. On passenger ships this question seems to be solved by the adoption of the so-called thermotanks for the ventilation of the living-rooms, in which the fresh air is heated by passing over caloriferes, the heating coils being filled according to requirement with the cooling fluid by which means the air becomes cooled instead of heated. However, the adoption of this system of thermotanks on ships is by no means universal. As before mentioned, the manner of isolating the conduits and walls is of the utmost importance. The modern iron-built ships are such good conductors of heat that the heat of the constructive portions in the naturally hot engine and boiler rooms makes itself felt almost throughout the whole vessel. The best isolation proves to be a complete lining of all the iron parts of the walls in the rooms to be cooled with cork-stone combined with wains coting. Loose isolating materials, such as Sawdust, charcoal powder, cork powder etc. as fillings between wooden partitions have not answered on board ships be- cause owing to the vessel's vibrations they sinter together whereby the upper portions of the isolating layers become emptied. Inside the storage rooms particular attention must also be given to lining the partitions with zink sheeting soldered perfectly water-tight to prevent the isolating partitions from rotting. Although these brief explanations can lay no claim whatever to being a complete treatment of all the questions to be considered in the refrigerating plants in ships, still I believe to have mentioned the chief points on the subject and must leave it to professional refrigeration technicians to decide to what extent they may be suggestive of further improvements in the plants. 901 The Ice Manufacture. By M. Sandras, Member of the French Association of Refrigeration. Director of La Com- pagnie Parisienne de Glace Transparente. (Evans, Sandras & Co.) General Considerations. The trade in artificial ice, quite wrongly called artificial in our opinion, has made considerable progress in France during the last few years. It was not very long ago that the City of Paris drew the greater part of its supplies from the Lakes and Reservoirs of the Seine District; to-day the uncertainty of the harvest of natural ice, the growing needs of customers, and the very exaggerated precautions of the public Health Officers have caused the consumption of natural ice to disappear almost completely from Paris. The various plants which have been created by various needs, can actually make about 1000 tons per day. The supply of Paris, whose con- Sumption reaches an average of 150,000 tons per year, is thus largely assured. & The Provinces have followed in the path of the Capital, and, although there exists no possible comparison or similarity between the purposes for which the Ice is used, or the net prices of practical delivery in Paris and in the most important provincial towns, it may, nevertheless, be confidently asserted that ice factories are being extended or built, and, that a large number of seaports, where the only ice employed before for the needs of the fishing industry was natural ice from the Lakes of Norway of high price, and uncertain in arrival, have become important centres of pro- duction. Modern Manufacture, Cost and Sales Prices. A function gives rise to an organ, necessity gives birth to, developcs, and perfects production. The old air machines and oldfashioned apparatus have been superceded by modern compressors, with which are used all known means of economising fuel, Steam superheaters and feed water heaters, the use of engines using gas of low thermal value, etc. This best and most economical product has permeated the industry of France, lowering the price of ice considerably, even in the face of the numerous regulations which have been imposed upon it by the new Labour Legislation. In Paris, 902 for instance where the charges for delivery are considerable, and beyond Comparison with those of the other towns of France, ice, which was sold at one time at 50 francs per ton, is actually delivered to large customers for the avarage price of 40 francs. - In the Provinces the prices vary very much according to the locality. At Boulogne-sur-Mer, one of the most important fishing ports of France, the ice is delivered upon the boats, ready crushed, at a price of from 18 to 20 francs per ton. Our particular experience permits us to add that these prices in Boulogne give a better result to those interested than that of 40 francs in Paris. This statement is made simply to show the considerable differences which exist between the prices of manufacture and delivery in Paris and the Provinces, differences which it is not the object of this paper to discuss, but which render all comparison impossible from the start. It is, moreover, very difficult to establish a standard net price for manufactured ice, because too many variable factors enter into the compo- sition of this price, so that it is only when everything is finished that it is possible to determine it with certainty. There are, in fact, contingencies in the manufacture, storing, and sale of the product; also considerable variation because the sale is subject to so . great an extent to the influences of temperature, that an investigation of the account books can give as certain an indication of the temperature as the best of thermometers. - --> In Summer it only needs stormy weather to diminish the demand by 100 per cent, but since all the expenses remain the same, the impossibility of a constant price is obvious. * If, for instance, one year is hot and all the factories of one company, or ail the machinery of one factory are active during four or five months of the year, if the reserves are broken into during the selling season, the result will be altogether different from that of a cold year which makes it necessary to suspend the manufacture of a part of the product, and which does not allow of drawing from stock. This difference affects, above all, the cost of delivery; in Paris this delivery is made in districts. The same carriers go the same rounds, and to the same customers each day, and at the same times of the day. The result of this is, that the charges of delivery are proportional, not to the distance carried, but to the quantity of ice delivered per wagon; and a decrease in temperature immediately produces a decrease in the quantity to be delivered, which increases the charges of delivery to so great an extent that these charges far exceed the value of the product delivered. Besides, the necessity of delivering in the mornings makes it necessary to load the wagons during the night; and, during the hot season, to commence loading at 7 o'clock in the evening, in order that all the wagons may be ready to set out in the morning at 5 o'clock; and, besides the increase in labour charges which this night work involves, a wagon loaded 903 on a warm night at 7 p. m., and which is not unloaded until the next morning, loses, during 5 to 7 hours, almost 10 per cent of its contents. We thought it best to give all these details in order to bring home the conditions upon which the net cost of delivery of ice generally depend, and the dislocation of business which is suffered by manufacturers who blindly accept certain valuations. f We have before us a scheme published by a refrigeration journal for a factory intended to produce 50 tons of ice per day, and the net cost per ton of ice, not including rent of ground, accidents to machinery and un- foreseen circumstances, is estimated at Seven francs thirty centimes. - Assuming all the expenses correct, there is a fundamental error in cstimating the price, and that is that the price is reckoned upon a basis of a constant daily production of 50 tons, but that as it stands, leaves many things out of account, the cost being subject, not only to accidents which may crop up, but the impossibility of manufacturing when the stores are full and there being no sale for it when made. The latter eventuality always asserts itself in winter, often in spring and autumn, and may even, in certain years, crop up in Summer. It is probably this difference between the real cost of delivery, and the theoretical estimates, which, from 1875 to 1903, has caused the dis- appearance from Paris of about 15 companies formed for the manufacture of ice, and certain of which, namely La Société Générale de Glace Pure and La Société de Glace hygiènique, had 3,200,000 and 4,250,000 francs capital respectively. * - * * Nevertheless it is only fair to say that the above serious inconveniences are especially peculiar to the Metropolis, and that in the Provinces it is quite different. There the short length of the rounds which allows of the delivery wagons returning to the factories for reloading; and the sale of ice for the fising industry, which is the principal work connected with ice in the Provinces, is quite another matter. This ice is sold crushed, and customers are quite indifferent as to its clearness; delivery is made from the factory to the quays where the boats land, generally a very short distance; there is not the least necessity to load the wagons in advance, and hence the night work of the loaders is obviated; delivery is made in large quantities, the wagons go to and fro from the factory to the quay completely filled, facts which considerably diminish the delivery charges. Finally the use of ice for the preservation of fish is influenced much less by temperature than that sold daily to provision dealers, and the principal fishing season is in the autumn, which from the manufacturers point of view minimises inconveniences of all sorts, created by high temperatures. Opaque ice. — Transparent ice. Ice may be made opaque or transparent, it assumes both these aspects often at the same time and in the same block. - 904 Which is preferable? For refrigeration where there is no contact with the foodstuff, the question seems an unimportant one. From a theoretical standpoint it may be claimed that the salts in opaque ice hasten melting, but then the quicker the melting, the more intense is the cold produced; but, if it is required to use the ice in direct contact with the food stuffs, as, for example, the pre- servation of fish, the use of clear ice is greatly to be preferred, because opaque ice, when melted, leaves a deposit upon the surface of the food- stuffs, submitted to its action, a covering of calcium salts, which, if they are not particularly undesirable from a hygienic point of view spoil the appearance of the goods. Lastly, if the ice is intended to be put into drinks or to be directly absorbed, clear ice is far more desirable in addition to its more attractive appearance. The work of the eminent head of the chemical laboratory of the Ministry of Finance has shown that the transparent parts of a block of ice are generally free from bacteria, and impurities. We will speak of this very remarkable discovery further, when we discuss ice from the point of view of hygiene. Manufacture of transparent ice. There exists numerous ways of making transparent ice, those generally employed are: 1. The use of water more or less distilled obtained by the condensation of the exhaust steam from engines. . The agitation of the water while freezing. 3. Charging of compressed air into the ice cans. 4. Slow freezing by sufficiently enlarged freezing surfaces. 2 Employment of condensed exhaust steam. The employment of condensed exhaust steam from engines has given rise to many misconceptions. Numerous manufacturers imagine, all in good faith, that the water produced by the exhaust steam from their engines can produce ice not only transparent but also very pure. Unfortunately, whate- ver means are used to separate the steam from the escaped oil, which has been used for the lubrication of the cylinders of the engines, this separa- tion can never be complete, and the water of condensation still retains not only an appreciable quantity of oil in Suspension, but the odour of these mineral oils communicates too often a suspicious colour and odour to the ice obtained from the water. It is enough to place the ends of the fingers into a receptacle con- taining ice made thus, to ascertain immediately by the sensation of the melted ice, how this ice has been obtained. Again, the condensed engine steam is never obtainable in sufficient quantity to supply all the ice turned out by the ice machines. 905 -- There is another and far preferable process, which consists in making the ice from the town supply water; to remove by suction before it is fro- zen, the water remaining in the central portion of the block, and to replace it by distilled water. This mode of operation, as it considerably reduces the amount of distilled water necessary, permits of water being specially obtained and con- sequently with all the qualities desirable for the use for which it is inten- ded; the opaque part is always the core of the block, this core being re- moved and replaced by distilled water, the ice is transparent in all parts. The disadvantage of this system is that it requires a special installation and manipulations which retard the freezing process. It requires a special coil of piping to pump out the water from the central parts of the moulds, apparatus for distilling the water to refil these, and lastly special apparatus to replace the distilled water in the moulds. All these operations complicate quite considerably the filling and turning out of the moulds; and it is from this reason that we are not very partial to them. The manufacture of transparent ice by the Agitation of the water. The process which consists in agitating the water to expel the air, pro- duces remarkable results in the manufacture of ice in large blocks, but is far from being so effectual with moulds of 25, 30 or 40 kilogram. We make part of our manufactures in blocks of 300 kilogram, this is made in fixed tanks divided into compartments by hollow plates through which circulates the refrigerating liquid, conveying the cold; these tanks are fitted with double bottoms, upon which rest the plates separating the blocks (figs. 1 and 2); each compartment communicates with the double bottom by means of holes drilled for this purpose. The agitation is effected by means of large wooden blades mechanically actuated, which move up and down in a lateral space provided in the tank and separated from the moulds by a water-tight partition, but communicating with the double bottom, so that the motion of the blade moves the whole mass of the liquid. The position of this blade admits of its fulfilling its function until complete freezing takes place in the tank (fig. 3). The result of this is that blocks thus made are very remarkably trans- parent throughout, and it is not necessary to remove the agitating blade at any time, it is enough to disconnect the mechanism when freezing is complete. - Agitation in the moulds presents many more difficulties and gives much lcss good results. Each mould must be provided with an agitating blade so that care must be taken to remove it before freezing is finished, to keep the blade from becoming ſixed in the block of ice; from the time that the blade is removed agitation ceases, and since the block is not completely solidified, 06 there necessarily remains an opaque part in the centre when freezing is entirely finished. In addition since modern installations have a pushing gear which always allow the finished ice to be removed from one end of the tank, and the cans to be frozen to be plunged into the other end; this system is ab- solutely inapplicable. The Manufacture of Transparent ice by Compressed air. Another process consists in admitting compressed air into the moulds, it requires a special installation of pipes to deliver the air, an air compressor and a special arrangement of the part below the moulds. Fig. 1. * -s Ground-plan. Tank, blocks of 300 kilogrammes. 1 metre. We admit that we have not been able to obtain very precise information, as to tho results obtained by this system, as not yet extensively in use, but the complications which its employment gives rise to do not enable us to recommend it. The Manufacture of transparent ice by slow Freezing. This last process is, in our opinion, the simplest, the most effective, and yields at the same time absolutely transparent ice, and the best use of the apparatus. The real inconvenience is that it is necessary with slow freezing to have the refrigerating surfaces greatly enlarged, which increases the first cost, because, for given production, a much larger tank and a larger number - - . | | _ |× si.---+------- ––––––––––––––––––––––––––––––––- ---- |- （~~~~ -.-.-.-.-.- |- l)ouble-bottom. Refrigerating liquid. Passage of the refrigerating liquid in the plates of the tank. 908. of moulds in consequence, and what is more, a larger site, and plant are required. But if these necessary conditions are numerous, the advantages derived from its use are considerable. Ice manufactured at a maximum of 3" below zero centigrade would be of perfect clearness. If care be taken to have the moulds at such a height that a part (about one tenth of their volume) is not immersed in the freezing liquid, all the impurities rise to the unfrozen tap part, and are got rid of the moment the moulds are inverted; lastly, as freezing takes place slowly, but over a large surface, the cold is much better utilized, and a plant with a normal output of , 30 tons in 24 hours can easily give more. The results of our practical experience entitles us to say, that a com- pressor making 30 tons of ice per 24 hours in moulds of an average cross section of 0.20 x 0.15 metres and a capacity 40 kilogrammes, may easily produce 35 to 36 tons of transparent ice, reckoning upon a capacity of 80 tons, given by two thousand 40 kilogramme moulds. These figures may serve to determine the sizes necessary for a pro- duction of blocks of other weights and Sections. Ice making from the point of view of public hygiene. In treating this question we must avoid all exaggeration, and bear in mind that the use of ice is infinitesimal compared to that of water. In Paris there is distributed an average of five hundred thousand tons of water per day to the population, more for domestic use than for drinking, while the amount of ice consumed only reaches one hundred and fifty thousand tons in a year. -- te Comparison of these two figures suffices immediately to show the small risk which the use of ice, even impure ice, would cause to public health. In spite of this, there was a time when the public health department generally composed of eminent men, learned in their specialities, but un- fortunately not very competent from a practical point of view, gave out . drastic regulations for the ice traffic, the smallest defect of which was that they were incffectual and inapplicable. This kind of spirit, is happily disappearing, and now the police regu- lations in France simply require, in accordance with common sense, that the wather intended to make ice for consumption shall be that distributcd by the corporations for public consumption. This is however the same as the resolution adopted by the International Congress recently assembled if, Paris. The results of the very conclusive experiments by Dr. Bordas, the eminent head of the Chemical Laboratory of the Minister of Finance, do not go against this happy modification. # Having always made our ice with water from the mains of the City of Paris, we have very often been surprised, to find that pieces of ice of our manufacture analysed by the Municipal Laboratory of the City of Paris, 909 gave results having no relation with the analysis of the water used to make them; moreover, pieces taken from the same block gave absolutely different results; and under the regulation concerning the sale of ice, brought into force on December 13", 1899, which require that only ice which gave on melting drinkable water should be on sale for consumption, it happened very Fig 3 - Blade of the stirring contrivance = Double bottom. Tank, blocks of 300 kilogrammes. frequently that one piece was judged good and another bad, in the ice taken, according to what part of the block it had been broken from. The explanation of this phenomenon, which greatly astonished the manufacturers was finally given in the memorandum which Dr. Bordas sub- - mitted to L'Academie des Sciences, through Dr. Brouardel. We cannot do better than reproduce this memorandum: 910 “When the water contained in a cylindrical vessel is subjected to the action of a temperature of say 10° C to 15° C below zero centigrade, in- vestigation shows that the solidification of the liquid proceeds from the walls to the centre of the vessel. In repeating the above experiment with water containing matter in Suspensions, such as organic substances, a solution of carmine, micro- organisms, or Substances in solution such as salts of potassium, glucose, aniline dyes, sulphate of Strychnine, rennet, etc., since the solidification of water takes place from the wall of the vessel to the centre, there is ob- tained in the latter part a liquid containing all these bodies in suspension and all these salts in solution. » Further, at the time of the first International Refrigeration Congress, the author of this paper gave a report on ice used for consumption which reaffirms in a most complete manner, all that it is necessary to know on this subject. We allow ourselves in all modesty to recall, that when Dr. Bordas was conducting his researches upon the effects of freezing, he was good enough to honour us greatly by allowing us to help him in as far as we were able in his interesting experiments. We have mentioned above that part of our product is made in blocks of 300 kilogram each, the dimensions of which are 120 × 1.10 × 0.25 metres. Dr. Bordas sent us a small quantity of carmine, which we dissolved in the freezing water, and which made it resemble wine of a most beautiful red. When freezing was finished the outer parts of the block were absolutely transparent and all the carmine was concentrated in the central part. . The result of these facts is that a block of ice having its central core removed, would be absolutely pure. It is always very difficult to get custo- mers to accept unfinished blocks, but in the cases with very few exceptions, where the ice is used directly for consumption, it is enough for consumers to choose ice transparent on the outside of the block, to be certain of having pure ice. And we will conclude by proposing the resolution that: In all hygiene boards and labour boards, parliamentary, municipal or other commissions, whose duty it is to make rules which impose decrees and legislation on all that concerns the regulation of commerce and industry, the greatest scope should be given to the dealers and manufacturers so as to allow them to make known their desiderata, to submit their observations, and, lastly, to give that information which their competence in their own affairs allows them only to possess. The great Colbert did not take any action affecting commerce or industry without previously consulting the experienced men in the industries or corporations. f We think that his successors could do this much without compromising themselves. 911 Report of Proceedings of Commission IV. I* Sitting, 6* October, 1910. . The Sitting began at 2 p.m., and ended at 4:45 p. m. Honorary President: Theo Ko 1 is cher (U. S. A.); President: Ing. Phillip P or ges, General-Director of the Maschinen- und Waggonbau- fabriks-A-G, Simmering, and the Machine factory at Brünn-Königsfeld; Vice-President: Ing. Karl He impel, Director of the Wiener Krystalleisfabrik. President Generaldirektor Porges took the chair giving the following address: - As president of Commission IV I offer a hearty welcome to all of you who, from far and near, have come to take part in Our Congress, and I trust you will take an active interest in the work and discussions of Commission IV. Our Commission has been given the following tasks: 1. Question: -Ice manufacture and artificial ice-rinks. You will hear - interesting papers on both themes and will also have opportunity to inspect both an ice factory and an artificial ice-rink. t 2. Question: The use of refrigeration in the tobacco trade. There are two interesting papers on this theme also. 3. Question: Use of refrigeration in other and in chemical industries: a) Petroleum and paraffin production; a series of papers has been notified on this subject for Friday; 6) Tanning and the extraction of tannin; on this subject a paper is notified for Saturday; c) Colour manufacture, dye-works and printing works are represented by several interesting papers; d) Fat goods; a paper will be read on this subject on Saturday. 4. Question: The cooling and airing of dwellings, work-rooms, and meeting-rooms; three interesting papers are notified on this subject for Saturday. 5. Question: The use of refrigeration in gardening and in silk farming; here too there will be two papers. 6. Question: The use of refrigeration in mining and smelting; there will be a paper on the first subject on Thursday, and on the second sub- ject on Friday. º 7. Question: Inventions and application in the arrangements and appli- cation to powder and ammunition magazines; this subject is only partially dealt with in an interesting paper on the cooling of ships. You see that the questions laid before us are answered from many quarters, and we hope by our work at the Congress to assist in the solution of the questions, and by the information given concerning the progress in this sphere to stimulate to further work. We have endeavoured so to arrange the papers that those on similar or related subjects shall be taken on the same day. You will, however, find printed lists giving the order of the papers. º My task of introducing the discussions of the Commission being now fulfilled, I request that the Honorary Presidents be elected. I beg to propose the following gentlemen and request that they be elected with acclamation. For France: Prince Roland B on a part e, Ing. Gu is e1 in and Emil B a r be t, president of the Society of Civil Engineers; for Germany: Geheimrat Prof. v. L in d e, Prof. Hans L or en z and Obering. B an field; - for England: Director J. de Saugy, Engineer R. M. Le on a r d: for Italy: Prof. Men o z zi; - for Hungary: Julius v. Rub in e k, J. v. Serb a n; for Holland: Privatdozent J. F. H. Ko op m a n; United States: President Theo Ko 1 is c her ; Argentina: Prof. Engineer Emilio P a 1 a c io. President Porges greeted those present, also in the French and English languages. Obering. R. Banfield (Germany) gives his paper on 2The use of a r tificial cold in s m el ting works «. (See p. 865.) I will take the liberty, for the sake of explanation, to show some diagrams. (Demonstration.) President Porges: I put the question whether the Gentlemen wish to discuss this subject. I call upon * Obering. A Tegetmayer (Germany): In order that those gentlemen who are interested in the practical side of this question may have some idea of the dimensions, I would like to remark that this air cooling plant has the small surface of 36,000 sqare metres. The filling and starting are effected without the least difficulty. The building is 20 metres high, 40 metres broad and 46 metres long. Thus these are quite enormous dimensions. Delegate Kolischer (Philadelphia): I happen to be fairly experienced in the mechanical side of this question. The Pittsburg Works, the Isabella, was one of the first in which this process was employed. The costs of the plant are very considerable, the machines are driven by steam. 40,000 cubic 913 foot of cooled air were guranteed per minute. The degree of moisture was 8.5 grammes per cubic metre. This process has proved itself advantageous with us in the United States. I have spoken with Geidey myself, he was rather vexed that he should have been attacked at the first Congress and that foreign inventors had no confidence in his process. The reason why no more such plants are erected in the United States is simply that we are awaiting the lapse of the G e i le y patent, which will be in about one year's time. That is, in order to save the high costs of the patent, gentlemen prefer to wait one more year and after that to order the plant. In general t this process is looked upon as very advantageous in the United States, so far as concerns economy and quality of the iron. Obering. R. Banfield (Germany): I would merely like to explain why we in Germany distrust the process. It is affirmed, I do not know whether justly or unjustly, that the pre-warming of the blast, in Germany and probably in Austria also, takes place much more completely than in the United States, and it is said that the advantage of air drying consists in the first place in the raising of the temperature in certain regions of the furnace. And those gentlemen with whom I have spoken have told me that they attain a temperature almost as high as Geiley does with his process. President Porges: It was pointed out in Austria that if this drying of the air were really so advantageous, it must be particularly noticeable in the winter months. It has been found that work can be more advantageously effected with cold dry air, it is true, but the advantages do not seem to be so great as to justify the enormous outlay. This objection it has never been possible to overcome. There are also other and smaller circumstances which come into consideration, so that there always remains the question whether the advantages, especially as they have been viewed in America, are really to be maintained for our Austrian conditions too, taking the more temperate climate into consideration. Prof. Dr. Josef v. Ehrenwerth (Austria): Experience shows that the saving in fuel for furnaces was the higher, the worse were the results formerly worked with, the lower the blast temperature employed. The first statements from America sounded so favourable principally on account of the fact that over there only moderate blast temperatures were employed (slightly over 400). Theoretical calculations on this subject, however, show the Geiley in- formation to be absolutely trustworthy. That so little confidence is exhibited towards blast drying in Europe, and especially on the continent, is the result, in the first place, of the fact that primarily only that expenditure of heat is taken into consideration which effects the destruction of the moisture in the air, and which is saved by the drying. As a result of saving in fuel there arise fewer gases which consequently flow more slowly through the furnace and SO part with more of their heat and pass out of the furnace cooler. A further result is that the greatest part of the furnace is cooler, that is, less heat is lost by radiation. The saving on this last account exceeds 5S 914 that first mentioned, and under otherwise equal conditions will show a higher percentage the worse the furnace is insulated. r President Porges: I call on Dozent J. F. H. Koopman to give his paper on >The cooling of houses and buildings in tropical countries.<. (See p. 834.) . *** * President Porges: I call on Professor Wagner. Prof. Heinrich Wagner (Austria) gives his paper on "Refrigeration plants on ships. (See p. 897). - Delegate Kolischer (taking over the chair): Does anyone desire to raise a question ? President Porges: I would like to ask what the size is of refrigeration plants on ships, how many calories, etc. * Prof. H. Wagner (Austria): I am not able to give exact data, but experts will be able to gauge the size if I mention that to drive the engines about 70 horse power are requisite. Chairman Kolischer: When you speak of refrigeration machines on steamers, do you refer to ammonia or to air engines? 4. Prof. H. Wagner (Austria): The smaller engines are almost exclusively air engines. On the newest ships and in larger plants carbonic acid engines are also in use. Chairman Kolischer: Do you speak of war vessels or of merchantmen? Prof. H. Wagner (Austria): Especially for war ships. Ammonia engines have been used on the ships of the Austrian merchant service, and carbonic acid engines, too, on the newest ships. The use of ammonia is disagreable on account of the fact that through the vibration leaks occur allowing the ammonia to flow out. * President Porges: It would interest us to learn how the arrangements under discussion are carried out on English war-ships. Delegate de Saugy (England): Air cooling is also employed on English ships. We have three or four groups of magazines and in each group is a refrigeration unit. Generally the same machines are used for all refrigeration units and connected together so that if one unit in front or at the back cannot run any longer the work is done with another unit. It is the tendency to make use more and more of electrical power. The same machines are now used in a few other navies too for cooling hospitals or the cabins of the commanders. (A voice: How?) With Thermo-tanks. Prof. H. Wagner (Austria: Some gentlemen will be interested to learn why these Thermo-tanks, which as stated are used on English ships, are not employed generally on war-ships. It is because these war-ships are incomparably more subdivided — by water proof walls — than all other vessels. Consequently very many rooms would have to be provided with out-flow and in-flow conduits which must always be water-tight. The execution would become much more complicated than would be justified by the gain. In the case of large rooms, however, this can be very simply done. There are large conduits 915 from thermo-tanks which pass a whole row of cabins and consequently. represent a very simple plant. t --- President Porges: I now close the Sitting and request the Gentlemen to meet here again to-morrow as punctually as possible at 10 o'clock. a.-s-s-s-s-s-s-s-s-s--" 2*Sitting, 7” October, 1910. The Sitting began at 10.30 a. m. and ended at 12:45 p. m. Honorary President: Theo Kolischer, United States; President: Ing. Philipp Porges, General-Director of the Maschinen- und Waggonfabriks-A-G., Simmering, and the Machine factory at Brünn-Königsfeld; Vice-President: Ing. Karl Heimpel, Director of the Vienna Crystal Ice Factory. Chairman Kolischer: To-day's programme comprises the application of cold in the petroleum and paraffin industries. We have the good fortune to welcome recognised authorities in this branch, among them President Generaldirektor Porges who has gained great reputation in the branch mentioned. He will give a paper on >The application of artificial cold in the paraffin industry of Austria-Hungary.<. I would like to make a remark regarding the settlement of the papers on the petroleum and paraffin industry. As you know, we have not very much time for our papers and must reproduce them in the most concise form possible. It is therefore to be recommended that we do not take up the discussion after each separate paper, but first hear all the papers and then enter into a general discussion. I beg to ask the Gentlemen if they are in agreement with this proposal. (Agreement.) I call on Generaldirektor Porges to open the series of papers. Generaldirektor Porges (Austria): 'On the application of arti- ficial cold in the petro 1 eu m a n d p a raffin in dustry of Austria-Hungary. (See p. 685.) Generaldirektor Porges showed lime-light views. Obering. R. Banfield (Germany), taking over the chair: In agreement with the proposal previously made and accepted the discussion of this paper will take place later on. I now call on Engineer A. Guiselin to give his paper on "The use of cold in the pet roleum in dustry. (See p. 677.) * President Porges: Direktor E. S. Kerkhoven, Holland, wo has been prevented from attending the Congress, has requested that his paper may be read. This paper is very short but very interesting and I will read it myself. (Reads.) > Refrige ration technics in connection with the p a raffin in dustry in Ho 11 and a n d the Dutch Colonies. (See p. 683.) Chairman Banfield (Germany): The next paper is that of Engineer Jos. Weiser, Austria, on > M an u facturing processes which serve ^ 58% 916 for the ob tention of p a raffin with the application of a r ti- ficial cold». (See p. 691.) Mr. Weiser is not present, I therefore open the discussion on the papers read. Does any Gentleman wish to speak? Director I. de Saugy (England): I would like to point out something. So far we have only spoken of ammonia refrigerating machines for the cooling of paraffin. My firm J. & E. Hall, Dartford, has made a large number of installations with carbonic acid machines, and that in quite tropical districts. The last two machines delivered were each for 100 tons of ice. These machines are only for the refrigeration of mineral petroleum and give very good results. Otherwise however, there are in this district not many carbonic acid machines. * Chairman R. Banfield (Germany): May I ask with what temperature you work there 2 Director I. de Saugy (England): We cool at 32–34° Celsius. The lowest margin is — 5° salt-water. Chairman R. Banfield (Germany): How is the purity of the separated paraffin Are there still traces of the oil? *. º President Porges: If you look at the bottle I have had put up here you will notice that the separated paraffin is completely black and mixed with oil. It must be put through another cleaning process. It is first pressed and the Scales present extracted from the paraffin. The paraffin is purified by cleaning. There still remains 30–40 per cent of the oil, and this must be removed by a further process. Kommerzialrat David Fanto (Austria): I am very much surprised by the Statements of the previous speaker to the effect that he has had good experiences with carbonic acid machines. In my factory I had such machines of 150.000 calories per hour but had very sad experiences with them. Their effectiveness in summer with warm cooling water, was practi- cally nil. In fact these machines had to be removed and made use of for other purposes because they were not suitable for the intended object. In any case it is very interesting that in the home of the previous speaker with SO high a temperature carbonic acid should yet be used. - Chairman R. Banfield (Germany). It is perhaps better that we do not go into the system question known to all of us. ^. * President Porges: I would like to point out that from experience with the carbonic acid machines we know that at very low temperatures the effectiveness decreases enormously especially if no cold cooling water is available. Since carbonic acid has a high specific heat of the liquid, it is evident that the carbonic acid machine did not satisfy the object as soon as the temperature of the cooling water was high and at the same time very low temperatures were demanded. In our paraffin factory we reach —189. We are poor people here, we have only 51/2 per cent paraffin content in Austria, but I know of a paraffin oil in Borneo which has from 12–15 per cent paraffin content. There, however, they do not desire to extract 917 the whole of the paraffin from the oil, as a rule, but only the high paraffin, for which a low temperature is not necessary. We know that the critical point of carbonic acid is about 31.5°. Beyond that there is practically no further proper liquefaction. For a long time it was believed in consequence that a cooling by carbonic acid was no longer possible above this temperature. This, then, is not quite correct. The effect of the machine decreases, it is true, and cold that is obtained is then purely an expansion phenomenon during the passage of the gases. Indeed, the process in the liquefaction of air by the Linde method rests upon this fact, that the permanent gases do not behave like permanent gases. In spite of this, however, a certain cooling effect takes place Solely on account of the turning off of these compressed steams which are above the critical point, but the effect is very slight when great power is employed. We started, however, from another question, the system question, which is of fairly considerable interest to all those who are closely connected with the manufacture of paraffin. Even if this question was not the subject of a paper yet it is interesting. It was much discussed and it is very inter- esting to hear the opinions of various industrialists on the sphere of the manufacture of paraffin, because this leads to an explanation. Theo Kolischer (United States): The company I represent has put up very many installations in Pensylvania in paraffin factories but so far as I know none with carbonic acid. I must beg Mr. de S a u gy to excuse me, that he may not think that I make advertisement here, but I can assure you that we have always returned again to ammonia machines. President N. N. Hiller (United States): The Carbondale Machine Co. at Carbondale, whom I represent, builds refrigerating machines of 10 to 15 tons effect and delivers almost all the machines for the Standard Oil Co. yet almost exclusively absorption machines; and those compression machines that are still at the Standard Works will also be replaced by absorption machines. ---- Chairman R. Banfield (Germany): Does anyone else desire to speak (No one replies). I therefore consider the discussion on this subject closed and call on Professor C la u de. Prof. Claude (France) gives his paper on 2 T he r e o b ten ti on of the vap ours from v o 1 a tile liquids b y colds. (See p. 810.) Prof. Hans Lorenz (Germany) taking the Chair: This paper will be distributed in print. Has any gentleman any remark to make? Such is not the case, I call on Mr. Engineer D rob n i a k, Austria, for his paper on shaft deepening by means of a freezing process. Engineer Franz Drobniak, director of mines (Austria) gives his paper »The free Z in g pro c e s s in the de e pen in g o f s h a ft sº. (See p. 872.) Chairman Prof. Lorenz: I open the discussion on this subject. Does anyone wish to make any statement? 918 President Porges: I should like to ask how large such a refrigerating machine really is, how many calories it has, etc.? Franz Drobniak, mine director (Austria): I have given exact data in the printed paper, though I did not read them in order not to weary. In the plant described a machine of 70 horse powers was used, which drove two compressors. The one compressor was worked, the other was kept in reserve. Besides the two compressors there were three refrigerators, One Submersion condenser, one spraying condenser, one cooling water pump, one bucking pump and the requisite conduits. For exact data I refer to my printed paper. Theo Kolischer (United States): This process has not, properly speaking, acclimatised itself in the United States. I can remember that one firm entered a contract according to which it obtained the sole right of manufacture in the United States. This firm made a beginning, about 25 years ago, with a bridge in the neighbourhood of Philadelphia. Unfortunately the trials do not appear to have given any favourable result. In the last 15 years this process has been entirely given up, and according to all I hear from engineers, the Poetsch process is not thought to be advantageous in the United States. I should therefore like to ask if the process proves to be a practical one in Europe. - Engineer Franz Drobniak, mine director (Austria): The first experiences were rather unhappy ones; for what reason I do not know. Six years ago, however, I went on a journey for study to France and Belgium and saw a whole series of shafts which were deepened by the Poetsch method. The process has not yet been made use of in Austria, because it has not been necessary to work in quick sand. In the new district in Galicia, however, quick Sand is putting in a rather dangerous appearance. I sunk One shaft which had to be abandoned after 80 metres. I then applied the freezing process which answered very well. In Russian Poland as well the sunk shaft process has been applied at Niemce but it was afterwards given up for the freezing process by which very good results were attained. Theo Kolischer (United States): Perhaps the cause of the failure in the United States is to be sought in the fact that the demands are much higher there. The American is a man who rushes at everything and does it hastily, he will execute everything in the shortest time possible. In America large machine plants are often used merely in order to make a shaft in one tenth of the time that it took to make it in France. The American wants to be done with it in about six weeks, otherwise he says the pro- cess is no good. I am interested in the matter because we have the largest ice machines in the whole world. The process might indeed be successful on a small scale, but one has to reckon with American conditions, too, where everything is executed on a large scale and where it is necessary to make rapid progress. 919 Engineer Franz Drobniak, mine director (Austria): The shafts were fairly large in the cases mentioned: one measured four and the other five metres a CTOSS. & Director J. de Saugy (England): I remember a case many years ago in England in which a Belgian firm made use of this process and in which it was entirely successful. *. Theo Kolischer (United States): I know of a case at the Hekla Mine in Michigan, one of the richest copper mines of the world. The Poetsch method was used there, true not with success, and it is just from there that the opinion spread that the process was not successful as a general rule. In one such case I was myself the engineer, at the erection of a bridge at Philadelphia. The process was made use of, finally however the pipes were drawn out again and the old system was resorted to. Director J. de Saugy (England): Perhaps the shaft was not very deep? Chairman Prof. Lorenz (Germany): Does anyone else desire to speak 2 (No one answers). I then close the discussion and to-day's sitting, and thank the gentlemen for their attention. Engineer Franz Drobniak wishes to show a few further pictures. * Engineer Franz Drobniak, mine director, Austria, explains a series of lime light views. 3* Sitting, 8* October, 1910. The sitting began at 10 a. m. and ended at 12:45 p. m. Honorary President: Geheimrat Prof. v. Lind e, Germany President: Ing. Philipp Porges, Generaldirector of the Maschinen und Waggonbau- fabrik A.-G., at Simmering, and the machine factory at Brünn-Königsfeld; Vice-President: Ing. Karl Heim pel, director of the Vienna Crystal Ice Factory. President Porges : I open to-day's sitting and first call on Mister B out a ri c for his paper on >The use of refrige ration in the ca out ch u c in dustry K. Ing. Boutaric (France) gives his paper. (See p. 750.) President Porges: For the next point of the day's programme I call on Mr. Engineer Guise lin. Gentlemen, we have here to deal with a whole series of papers, namely those of Messrs. C a v a 1 i e r, O t t e n d a h 1, D up on t, Je a n ca t d and S a tie, T as sily and B O n to u x, which refer to the use of refrigeration in various branches of industry. Mr. G u is e1 in will therefore have the goodnes to give all these papers in One Series. * A. Guiselin (Frances): (See p. 738, 895, 741, 742, 745 and 703.) President Porges: I call on Mr. Professor C1 a u de. Prof. Georges Claude (France): Gentlemen, I am happy to be able to agree with the opinion of Mr. Gu is e1 in, that the use of refrigeration 920 in the chemical industry has a great future reserved for it. I may say that this question has long occupied my attention and I hope that I have succeeded in convincing those gentlemen who listened to my paper yester- day as to how easy it is, with the aid of artificial cold, to recover the gases which develop from volatile liquids during the manufacture of imitation silk, smokeless powder, celluloid, etc. Dr. Alfred Kraus (France) : It is important that the necessary attention be paid also to the question of the recovery and the separation of the naphthalene from coal gas, and this, too, is a province in which cold can be made use of. A. Guiselin (France): A report has been published by a prominent engineer under the pseudonym 2 Reidrers. In this may be read concerning the manner in which the naphtaline may be caught by means of cooling. The particular apparatus is called spiège à naphtaline « (Naphthaline trap). The process is too simple, and its use did not become general. President Porges: Does anyone desire to speak 2 (No one answers.) This not being the case I close the discussion. I think we all know well enough how important it is that the use of cold be introduced into various branches of industry; we have, however, always the question of cost to consider. Even when we know how the cold is to be applied there still remains the question whether the expense of using it stands in the right proportion to the result attained. It is certain, however, that with the progress of experiments both the expense of fittings and the cost of working will sink, and that we must strive to make a universal application possible. I believe that we all, chemists and machine engineers alike, must consider this problem and that it is also part of the work of the Congress to encourage the use of cold in various ways. In this sense we are grateful to Mr. G u is e1 in for his exhortations, although we must first seek ways in which the application is to be effected. I now call on Dr. K a v a n for his paper on 2 T he r a ti on a 1 a pp 1 ic at i on of a b so rp ti on re friger a ti O n e n g in e s in the c he m i ca 1 in d us try &. * Dr. J. Kavan, unversity lecturer, Austria, gives his paper. (See p. 735). President Porges: Professor C1 a u d e who read a very interesting paper yesterday on the recovery of the gases from volatile liquids, has announced a demonstration of a new life saving apparatus. I therefore beg that this demonstration be now rendered. Prof. Claude (France) demonstrates a new life Saving apparatus. (Applause). t - President Porges: I now call on Oberbaurat Eduard Enge 1 m a n n for his paper on 2 O p en a i r a r tific a l ice r in k sº. Ing. Oberbaurat Eduard Engelmann (Austria) gives his paper (See p. 886.) 921 President Porges: It was formerly very difficult to erect artificial ice rinks because the expense for fittings and working were altogether too high for societies recruited from the middle classes of the population. Through the present day arrangement it has now become much easier, and it is a thankworthy part of the work of our Congress to carry these ideas into the widest circles of the people. I think that where a part of the available ice machines are not required during the whole of winter this part should be made use of as basis for the production of ice rinks. I believe that this would be a method that might find imitation. Does anyone desire to speak respecting this paper? Obering. Giusepppe Cattaneo (Germany): In connection with the statements made in the last paper I should like to point out that extremely divergent views are expressed in the literature on the subject of the amount of cold required by artifical ice rinks. No great faith can be atta- ched to them. So far we have only data regarding artificial ice rinks in closed rooms. In such cases the influence of the changing temperature and weather are negligible. We found in Berlin, however, that the amount of cold required varied between 120 and 180 calories per square metre, but that this variation was almost entirely dependent upon the number of visitors. This may arise from the fact that in case of a large number of visitors to the hall there is a larger deposit of moisture, and perhaps the movement of the skaters over the ice also assists the development of warmth on the surface of the ice. On the strength of observations made we may say that in the morning a mist lies evenly over the surface of the ice but that this is scattered as Soon as skating begins. Unfortunately, as already said, we have a very sparse literuture. Whe should therefore be grateful for the information given to us which makes it possible to institute exact calculations. Oberbaurat Eduard Engelmann (Austria): I can confirm the sup- position put forward by my colleague from the ice rink in Berlin. I think that on the one hand the breathing of a large number of visitors must certainly be considered as a heat producer. This fails, however, in the case of an open air ice rink, and consequently observations can be made more exactly. We find in Vienna that when the music begins and the number of skaters is greatest — and this is between 6 and 7 p. m. — that just where the mist is shifted a visible thaw sets in, which, in spite of the work of the machines, may become so sharp that the surface actually sweats. The moisture from the air settles down in the form of water, and a higher machine effect is necessary to overcome this, that is to turn it to ice. Hence arise the variations from 120 to 180 calories with you in Berlin. I have also noticed that in artificial rinks one decreases the cold pro- duction. In Paris where they at first went up to —15°, they afterwards went down to 12°, and I think even to 8° now. On open air rinks we have to 922, remain within even smaller boundaries. On an average, 6" may be looked upon as a maximum, and success will be obtained with between 3 and 49 minus. President Porges: There is still one more paper on the day's pro- gramme namely one by Mr. Huize r > On drinking glasses of ice <. (See p. 590). Mr. Huizer not being present and time being already fairly advanced, I close the sitting and request the gentlemen to come here again on Mondy at 10 a. m. 4* Sitting, Io" October, 1910. The sitting began at 10 a. m., and ended at 12.45 p. m. President: Ing. Phillip Porges, General-Director of the Maschinen- und Waggonbaufabrik A.-G., at Simmering, and the machine factory at Brünn-Königsfeld; Vice-President: Ing. Karl Heim pel, Director of the Vienna Crystal Ice Factory. Generaldirektor Porges: I am instructed to state that the intended excursion to the oxygen works at Gumpoldskirchen will take place on Wednesday the 12th inst. Before we begin our programme to-day I beg to say that Mr. Hiller has given me a paper printed in English written by Mr. Henry T or ran ce, machine engineer at Carbondale, U. S. A., which paper will interest all of us. I will have the paper translated into German and added to the reports of the Congress. Those gentlemen, who take an interest in the paper may give me their adresses in order that the paper may be sent to them. I will now give you the main contents: It is a description of the cooling of the Exchange buildings in New York, a building of enormous dimensions. The content is 1,246,000 cubic foot, the building is 140 foot long, 80 foot high and 110 foot broad. This room is cooled against the outside temperature. The cooling process is such that at various points at the top of the room cooled air is introduced against which the warm air strikes and thereby the bad air below is cooled. A few smaller rooms are cooled by means of cold conduits. The whole plant has about 100,000 tons daily effect, that is, according to our reckoning, 12,000 kilogrammes per hour, or 1,400,000 calories. The plant is reported to work perfectly. I now request Dr. Erb a n to give his paper on >The import an ce and a pp 1 i cation of low temperatures for obtain in g, working, and improving textile thread sº. Dozent Dr. Franz Erban (Austria), gives his paper. (See p. 774), and continues: • As Dr. Kirch acker is hindered from attending I will also read his papers: "The influence and application of cold mer- ce rising”. (See p. 696). - President Porges: I call on Director Ritterm a n n for his paper and will then open the discussion for all three papers which bear upon the textile industry. - \ 923 Director Daniel Rittermann (Austria) gives his paper on "The application of cold in the manufacture of azote dye stuffs.<. (See p. 699.) President Porges: I now open the discussion and call on Dr. Schwarz. Dr. Richard Schwarz (Austria): Mr. Kirch acker says that the mercerisation effect is all the better if the tempperature is lower, this, however, only applies to lyes under 30% Beaumé. As in practice, however, the concentration is always between 30 and 35 degrees, therefore about 33 degrees, cold does not come into consideration at all. If, however, I reduce the concentration I must make use of cold in order to obtain the same effect. Expressed in money the use of cold effects no saving. One kilo of ice costs more than one kilo of lye. The amortisation of the machines must also be taken into account. Then, there is the further matter to be noticed (I do not know whether there is anything in literature about it) that the mercerisation effects are considerably higher if alcohol is added to the lye bath. We mercerise cotton that has been previously bleached, so that, practically there can be no mention of a fat content. In this case we have probably to deal with the introduction of the lye into the inner part of the thread, which is effected better at a higher temperature than at a lower one. Dr. Erban (Austria), university lecturer: I would like to make the following reply: It is pointed out in the paper that the cooling is particu- larly necessary, in the first case, when mixed fibres are mercerised, that is, those stuffs which are made from various kinds of thread, and in which a part of the material, the animal thread, must not be attacked, and in the second place, when with bright colours care has to be taken that the shades are preserved, and when by making use of cooled lyes less danger is incurred of altering the colours than would be if warmer lyes were employed. In these cases the question of cost comes less into consideration. Cooling would be resorted to in these cases even though the process were thereby made more expensive, because the point of first importance is the preser- vation of the material. In other cases I am of the opinion that there would be no great Saving achieved by making use of cold. Director Rittermann (Austria): The cooling is of value chiefly with goods that are mercerised in a raw state. The effect of the warmth upon the weaver's glue is fairly considerable, the cooling is necessary. Dr. Richard Schwarz (Austria): Cooling is probably of far greater importance for the sake of preserving the colour, for there are various operations in which the weaver's glue is extracted. Director Rittermann (Austria): Nowadays the goods are mercerised in a raw state; there cooling is necessary; the mercerisation is greatly improved thereby; I know that from experience and practice. President Porges: This afternoon there will be a sitting of the dele- gates before which the proposals put forward by Commission IV must be *~, 924 placed. I should therefore like now to break off with the reading of the papers, in order that the proposals may be discussed, which are to be placed before the delegates this afternoon. We have discussed the possibilities of the use of refrigeration in the chemical industry for a considerable length of time. As we have seen we are as yet but at the beginning of the application of cold. Just as in many cases of progress the beginning is slow, so here in the chemical industry there has been a slow progress at the commencement. We are proceeding to popularise the matter, to make or continue experiments, and we hope that at the next Congress there will be a far greater application of refri- geration to report. In order now to give the next Congress more basis for discussion than is possible for us to-day, the following proposal has been put forward by Dr. Kavan. (Reads). » In the course of the discussions of Commission IV it was urged that the use of cold be studied and furthered in those industries in which. hitherto, it has been applied to but a slight extent, or even not at all This question is of far reaching importance from two points of view; on the one hand many industries will be given the possibility of improving their methods of working, on the other hand a new market will be created for the machine industry. It is therefore advisable to discuss this question systematically. I accordingly put the proposal: It is desirable that a permanent, international commission be chosen for the purpose of studying this question, which shall take over the ini- tiative in this direction and which shall spread the results gained among various chemical industries, so that it may be possible to lay before the III" International Congress of Refrigeration the whole material systematically worked out and developed, that is, a report as to how far and in what manner a rational use of cold is possible in various chemical industriés.< President Porges: It is a remarkable coincidence that a proposal whose object is almost identical with that of the proposal just read has also been brought in by Mr. Guise 1 in in the name of the French members of the Congress. Translated it reads: » Considering the very limited application of refrigeration in the chemical and physical industries, in which, moreover, the primary condi- tions for an extensive application of cold in the future are satisfied, Mr. Gu is e1 in proposes: That previous to the holding of the III* Inter- national Congress of Refrigeration an international organisation may be created whose task it shall be to bring about much closer, relations bet- ween manufacturers of refrigerating machines and directors of chemical factories.< President Porges: These proposals run for the most part parallel. I beg you to express yourselves with regard to these proposals. I think, it is 925 of importance that by the next Congress we shall have made more pre- parations than hitherto. I say this in consideration of the slight use made of cold although the papers furnished very much inducement to its use. Mr. J. F. Nickerson (United States) speaks in English. Mr. Theo Kolischer (United States): At the wish of the President I will translate the remarks of Mr. Nickers on into German as well as I can. He is of the opinion that the Association Internationale is sufficiently provided with commissions, so that the creation of a further commission would only complicate the matter. There exists Commission III which also considers the application of refrigeration to industry, and Mr. Nickerson is of the opinion that it might perhaps be more to the purpose to draft the proposal to the effect that a sub-commission of Commission III be made, since otherwise a question of precedent would be raised. It might then happen that a proposal with similar purpose might be put forward by Commission III as well, and then, there would arise a number of commissions all having the same object. President Porges: In the work of preparation we saw that it was absolutely necessary to divide the work. It is quite impossible for Comis- sion III to take the chemical industry into consideration, seeing that it only deals with the provision branch. We have made the arrangement of com- missions, and each commission has an enormous field for its action. In general it would be quite right to choose such an international committee out of each commission, which committee should be as small as possible and should have to take the necessary preparations for the next Congress. It is absolutely impossible that machine engineers who occupy themselves with the construction of machines, should also spread the use of refrigeration in chemistry. For that the help of chemists is necessary, who may learn from the machine engineers what may be done, how much the matter will cost and what means are to be applied. Our Commission has the greatest need of such an international committee, because it has to deal with a sphere as yet unexplored. The matter is fairly complete as regards the manufacture of ice or the application of cold in meat halls etc.; there can only be improvements in these cases. We, however, are still at the commen- cement. Many chemical industries make no use whatever of refrigeration as yet, as its application is too little known, because the chemists are not in a position to make relative experiments at the universities and politechnics. Such experiments, however, certainly ought to be made. Therefore I believe that a commission would be useful for us. We have here to deal with the proposal of our Commission, which must then still be first discussed in the senate. If our Commission receives no special committee for itself, consisting of chemists and machine engineers, then the Commission will be unable to effect any work, seeing that this technical branch requires chemists and also machine builders, whereas other branches need only machine builders. Mr. J. F. Nickerson (United States) speaks in English. 926 Mr. Theo Kolischer United States [repeating the remarks of Mr. Nickers on in German]): Although Mr. Nick ers on fully appreciates the remarks of the President, yet he is of the opinion that a case of pre- cedent would be created by the acceptance of the proposal, as then other commissions would come forward with similar proposals and the creation of new commissions, so to speak, might be carried on indefinitely. He is of the opinion that it might be more advantageous merely to arrange a sub- committee. Prof. Eudo Monti (Italy) also expresses his opinion that the formation of a sub-committee would suffice, but pleads that such sub-committee must be international and consist of chemists and machine builders. Mr. J. F. Nickerson (United States) remarks that he will not hinder or combat the formation of a commission, but he would like to see a case of precedent for the formation of similar committees in the other commis- sions avoided. President Porges: It is all the same whether a commission or a com- mittee is arranged, the name is of no significance, but it is necessary to develop a fruitful agent and to arrive at a clear understanding as to the applicability of refrigeration to the chemical industry. I beg those gentleman who are in favour of such a commission being formed to raise their hands. (Done). I call for the counter test. (After a pause). The proposal is unanimously accepted. The committee is to be as international as possible. The committee shall make proposals in future, and that nation which has the management of the Congress from time to time shall undertake the task of making the report. I propose that the following gentlemen be elected in the committee: For America President Theo Ko 1 is cher, for Germany Obering. R. B a n field, for Austria Honorardozent Dr. K a v an and Generaldirektor P or ges, for France A. Gu is e lin, for England Director de S a u gy, for Italy Prof. Eudo M on ti. - (This proposal was accepted with acclamation). Austria would undertake the task of making the report for the next Congress. The committee is to have the right to complete itself by the addition of further members. - President Theo Kolischer (United States): I express my best thanks for the honour which the Chairman has shown to us Americans by nomi- nating me; but I think that there should be more chemists chosen in the commission, as the principal point is the application of refrigeration to the chemical industry. - President Porges: We must elect machine builders to the commission in order that they may make proposals and be able to enter into discussion with the chemists. - 927 Honorardozent Dr. Kavan (Austria): The commission ought not to be too numerous, it is to have the initiative. I and Mr. Gu is e1 in will take the chemical side in hand. It will be very agreeable to us if the other members of the committee are all machine builders. It is to only be a beginning, the rest must be accomplished by experts from the various branches. The smaller the commission the better. -- President Porges: I had thought that the commission would elect reporters, who, though they would not belong to the commission, would yet work with it. There is only the one question: how to arrange that It is important for all of us that we encourage the use of refrigeration and try to introduce it wherever possible. This does not arise merely out of ego- istical interests of machine manufacturers. It is only possible that engineers give the initial impulse. Each one in his own country is to make enquiries through the chemists of the various industries, to confer directly with the chemist, and all that the commission shall learn during the next three years in this sphere it must lay before the next congress. The commission will enter into connection with industrialists and from these obtain the necessary information. - * Messrs. de Vr i e s and C or be t t also had to read papers on * T he application of a r tific i a 1 c old in p 1 a n tº culture <, and on 2The application of cold in keep in g plan tS back and in the preservation of flowers.” (See p. 854 and 849.) As these gentlemen are not present the printed papers will be distributed. . President Porges: We will now pass to the section for tobacco. I call on Finanzrat Dr. Preisse c ker, official representative of the General Direction of the K. K. Austrian Tabakregie, - for his paper on >The application of low temperatures in the to b acco in dustry K. Finanzrat Dr. Preissecker (Austria) gives his paper. (See p. 665.) President Porges: Is there any question? I thank Dr. Preisse c ker for his interesting paper and now call on Dr. Gustav Poock to report on >The application of cold for destroying to b a c co W O r In S < . Gustav Poock (Brazil) gives his paper. (See p. 673.) Chairman: We thank Mr. Poo cle for his valuable paper. Mr. Ignaz Tel 1 er, director of the chemical laboratory at the Austrian Tabakregie desires to speak. Direktor Ignaz Teller (Austria): In conjunction with the remarks of Mr. Poo c k I will say something regarding another tobacco pest of the same species, which for preference attacks Turkish leaves, and, as I will soon show, is able to effect very great damage. This is a small brown beet e, only a few millimetres long, Lasioderma testacea, which deposits its eggs on Turkish tobacco leaves. The grubs which develop from these eggs go through their cycle of development on this subatratum, and effect enor- 928 mous damage, as you can see from the material I have brought. In many of these leaves there is only the skeleton left in consequence of this eating away. The whole covering of the leaf fails. But it is not only the eating by the grubs that renders the tobacco leaves valueless but also the ex- crement that these animals leave. The following case which occurred some years ago may serve to illustrate how greatly the pests named may embarras cigarette manufac- turers, at times. - * The Austrian Tabakregie at that time drew a large sending of cigarettes from Cairo. The cigarettes, packed in tin boxes arrived here in an apparently perfect condition, and were accepted without demur. Soon after they had been sent out to the trade, complaints began to come in from consumers, to the effect that these cigarettes contained worms. The matter was looked into, and it was found that no inconsiderable number of cigarettes had holes eaten in their cases. A closer examination brought to light grubs of the above mentioned beetle. The cigarrettes were of course withdrawn from the government sel- ling establishments and destroyed. - This case can evidently only be explained by the fact that the eggs of the insects were already on the leaves of the tobacco at the time when it was manufactured into cigarettes, but in consequence of their minutenes escaped the observation of the manufacturers in Cairo; during transport to Europe, or in the magazines of the Regie, the grubs crept out and commenced their work of destruction. The use of chemical means for destroying insects is not to be recom- mended on account of the danger for the quality of the tobacco; here, indeed, nothing else than artificial cold can do good service. (The speaker shows tobacco that has been eaten by Lasioderma.) • President Porges: I now call on Mr. Charles Spier er, representative of the Commercial Company of Salonica Ltd., to speak on 2 Col d a n d m o is tur e a s m e a n s for p r es e r v i ng the to b a c co 1 e a ves in a st a t e Suit a ble for w or king.< Charles Spierer (Turkey): Owing to want of exercise it is difficult for me to speak in German; I therefore withdraw in favour of Dr. Pre is S- ecker who will have the kindness to read my paper. President Porges (Austria): I call on Dr. Pre is secker to read Mr. Spier er's paper. (See p. 676.) - Finanzrat Dr. Preissecker (Austria): Allow me a few words more: With reference to the paper of Mr. Spier er just read, I should like to add that even now — although, it is true, in only a very primitive manner -- at the despatching localities of the tobacco factory at Ottakring, Vienna, in order to keep cigar cases and cigar covers in a fit state for working, they are preserved in specially constructed cases, in which the temperature is lowered by means of moistening the air. 929 Mssrs. He impe 1 and Be sle r of Liesing, near Vienna, have planned an air cooling and moistening plant in connection with an arrangement for dust extraction, for the tobacco factory at Hainburg, but for the present this is not being executed. A Congress Member: Surely we have long since reached the point where cold air can be used in store and work rooms! Gustav Poock (Brazil): But it is too dear, especially in the tropics. A Congress Member: Would Mr. Poo c k be good enough to tell me what quantity of tobacco we are considering in the case of the cooling process mentioned 2 # Gustav Poock (Brazil): It is not a matter of freezing my whole stock, but only of moderate quantities, which I freeze part at a time, namely, only such parts of the stock as show traces of worm; thus only that part enters the freezing chamber which it is absolutely necessary should do so. President Porges: I call on Direktor Karl He impe 1. Director Ing. Heimpel (Austria): The temperatures which we have to maintain in the work rooms are as a rule attainable, without making use of refrigerating machines, merely by using cooling water. In the tropics, it is true, this offers difficulties, because the temperature of the cooling water must not rise above 15" or 16", in Europe, however, such water is t everywhere obtainable. There are no technical difficulties in the way of producing the right temperatures and the right degrees of moisture in the air in the work rooms. I thank you for the suggestion to introduce such apparatuses into the tobacco branch too. President Porges: The following has most attracted my attention. It is certain that cold is made use of, and also that it offers many advan- tages; it is equally certain that the industry has, hitherto, approached this task in a very faint-hearted manner, because the refrigeration industry is in reality a new thing, and the expense appears far greater than it really is. When Mr. P o o c k states that in Brazil the application of cold is impossible on account of the cost, I remark that it would yet be possible to reduce the temperature of the water that was to be used for cooling the rooms, at but slight cost, and a reduction of this temperature, however slight, is of great importance. I should like to urge tobacco industrialist, if they should have any problem to solve, to apply with perfect confidence to the machine manufacturers who will study the matter and make propo- sals. There will be many studies and calculations necessary before we really achieve a result. Many tasks in the cooling of rooms, which offered great difficulties years ago, are now solved. The industry takes subjects into consideration in order to effect business. Tobacco is so expensive an article that refrigeration plants would certainly prove worth their cost, if they enabled us to avoid such pests as have been mentioned. Obering. R. Banfield (Germany): Is it possible to state what 'expenditure of money is necessary in order to preserve a given quantity 59 930 of tobacco, say for instance, 1000 kilogrammes, or what is the cost of a cooling plant or other method for the elimination of the dangers described, with good driving power and including amortisation? Against the cost of preservation we can put the value that is gained by the preservation of the tobacco. It therefore seems of interest to secure exact data on these matters, as to what kind of freezing chambers were used by Mr. Poo clº, and what are the expenses of the plant and working. Gustav Poock (Brazil); I have only employed relatively small freezing chambers (about 45:6 metres by 4.5 metres high); they are lined with zinc on well calked wooden insulation walls which, about 40 centimetres thick, are filled with sawdust and lime solution and have a hollow space of 20 centimetres between them and the outer walls; cold serpentines inside, below the insulating floor; below these zinc gutters, obliquely placed as protection against thaw-water, leading off to the outside of the building by means of syphon. The cold serpentines are filled with cooling water which circulates from the ice generator, or in part with ammonia, direct from the compressor. There are no windows, door very close, insulated, before it an ante-room, lighting electric. Such chambers hold from 8000 to 10,000 kilogrammes of tobacco in balls tightly compressed. There is a narrow passage through the centre; this is used to observe how far the cold has penetrated, which can be done by reading off the thermometers and also by feeling the tobacco. The costs were very various. At first I had to pay very much for experience. Yet I would rather not speak about the cost at present, for I am about to arrange the matter more cheaply. Hitherto, as far as I have been able to find out, no one else has made use of such chambers. Mine are connected with an ice factory. All further matters I would rather leave for the expert judgment of refrigeration technicists. The progress that has been made in the branch of refrigeration, and is daily made, is very pleasing. I am very pleased to have made the acquaintance of eminent technical experts at the Congress. From them and the previous speaker I have learned many things. Therefore my best thanks to you and also to our honoured president for his words. President Porges: I call on Oberfinanzrat Dr. Freiherr v. N at or p, official representative of the chief management of the Royal Hungarian Tabakregie. Oberfinanzrat Dr. v. Natorp (Hungary): At a special conference the Section for tobacco formulated the following resolution as the outcome of all the urgings of their members: »I. The Section for tobacco considers that the application of low tem- peratures in the tobacco industry is of advantage: a) as a means of preventing undesired after-fermentation during the preservation of raw tobacco, half and whole manufactures; 931 b) as a means for destroying or preventing the development of tobacco pests in fermented or manufactured tobacco. The Section recommends that the newest means of assis- tance of modern refrigeration technics be resorted to for the further development of this application of cold. II. The Section for tobacco draws the attention of tobacco industrialists to the following problems: - - a) In what way may refrigeration be applied to assist in preserving the dried or fermented tobacco leaves in a state fit for working, without injury to their quality? - b) Can the danger of the tobacco becoming mouldy be effectually avoided by the use of cold? c) Can the fermentation process be advantageously modified by a suitable application of cold? The Section recommends larger tobacco businesses to institute experiments in these directions.< In the name of the Section for tobacco I now beg to propose this text for acceptance as draft for an expression of the Congress. President Porges: Does anyone desire to make any remark I then put the resolution formulated by the Section for tobacco. It is unanimously accepted. I call on Dr. Stajit sch, chief of the Section for tobacco culture and official representative of the Servian x Administration Autonome des Monopoles.<. Dr. Urasch Stajitsch (Servia): As has already been said here, refri-, geration can have a very great influence upon the preservation of tobacco. We have annually about two million kilos of tobacco in our stores. The arrangement of a refrigeration plant for this quantity would certainly be very expensive. Can one of the previous speaker say how much, roughly speaking, a cold plant for the preservation of the quantity mentioned would cost? Would not the expense for such an extensive cold plant be so enormous that in consideration of the purpose to be served the arrangement would appear to be unlucrative for the particular tobacco company Gustav Poock (Brazil): I have not the data necessary for answering these questions at hand. For exact information, however, our experience up to the present does not seem to provide sufficient basis for calculation. President Porges: I should now like to express thanks to all the gentlemen who have taken part in the work of this Commission. In many respects it has not been an ungrateful task, because we have been able to find out much that had not been known to exist before. We were not in the position of a commission in which individual constructions or impro- vements of machines are proposed. Our Commission covers so enormous a sphere that we have to work many years in order to succeed in introducing refrigeration into the various industries. 59% As we have had so large a task before us we must really wonder that so much has been effected as is shown by the various papers. I request the gentlemen zealously to continue their labours. The commission proposed by us is practically only to have the object that before the next Congress there may be a centre to which one may refer if one has any new idea for a new application of refrigeration. The gentlemen of the tobacco industry might well apply to the commission also, if in the coming months they discover a new method of applying cold. It is often the case that a matter fails merely on account of the fact that a person is not able to see clearly the proper way to carry it through. We need only consider the development of the store-house. Twenty years ago we engineers were terrified. We thought that the cold plants for store-houses would be enormous and the costs in- superable. The whole question, however, is merely one of the cost, and it is a matter of great importance whether these goods are preserved or spoilt. If we have a permanent commission which receives information and deals with general questions which cannot be solved by one individual factory, then there will certainly be progress made in the sphere of the chemical industry, too. I hope that at the next congress we shall be able to effect more than has been possible at this one. (Applause.) There are still papers to be read by Professor Eudo M on ti on » Cooling processes for clearing and aging wine etc.<, and by Regierungsrat Eitner > On the application of cold in the leather industry . I now close this morning's Sitting and call the next Sitting for this afternoon at 4 p. m. 5* Sitting, Io" October, 1910. The Sitting began at 4 p. m. and ended at 5.15 p. m. Honorary President: Director de Saugy, England; President: Engineer Philipp Porges, general director of the Maschinen- und Waggonbaufabrik A.-G., at Simmering and the machine factory at Brünn-Königsfeld; Vice- President: Ing. Karl Heim pel, director of the Vienna Crystal Ice Factory. Chairmann Ing. Heimpel (Austria): I beg to open the Sitting and request Regierungsrat Eitner to give his paper. Regierungsrat Wilhelm Eitner (Austria) speaks on >The use of cold in the 1e a the r in dustry. (See p. 766.) Vice-President Heimpel (Austria): I thank the speaker in the name of those present for his interesting paper. I call on Director de Saugy who wishes to put a question. Director de Saugy (England): The speaker said that fresh skins must not freeze. Can one cool them if they are salted? I should like to ask at what temperature the skins can be stored after they have once been salted P Regierungsrat Wilhelm Eitner (Austria): If the skins still contain wet they must not freeze, especially if they have been salted, for then the salt 933 crystallizes, and the texture tears still more. Whether the skins have been Salted or not they must not freeze under any consideration whatever. H they have been salted they can stand a temperature even less than 10 degrees above zero. Do you mean when the dangerous fermentation sets in which is named fouling? - Director de Saugy (England): I am interested to know at what tem- perature one should store the skins. Regierungsrat Wilhelm Eitner (Austria): At about 10 degrees. If the lime is decreasing this temperature suffices entirely, both for the storing of Salted skins and also for dried skins, against moth. Vice-President Heimpel (Austria): I now call on Professor Monti for his paper. Prof. Dr. Eudo Monti (Italy) speaks in French on a "Cooling pro- cess for clearing and aging wines etc. (See p. 796.) Director de-Saugy (England): The paper of Professor Monti deserves the fullest recognition. The concentration of wines and other liquids is certainly most interesting. I have had opportunity to see the products which Professor Monti has prepared. In every country there are certainly products that might be preserved in this manner and then exported, which would lead to great saving in the cost of transport. There is certainly much to be done in this sphere. - - Director de Saugy (taking the Chair): Does anyone wish to raise a question? (After a pause.) Professor Monti has a further remark to make. Prof. Dr. Eudo Monti (Italy) speaks on the sicknesses of metals. Director de Saugy (interrupting): This paper does not belong to our Commission. As there is no further matter to deal with I close the Sitting. COMMISSION V. Transportation. 937 Statistics of Refrigerated Transportation. Report by M. Alfred de Wendrich. Official Delegate from the Russian Empire, vice-President of the International Association of Refrigeration, Senator of the Russian Empire, Lieutenant-General Engineer, Vice-President of the International Transport Comittee. Late Assistant Minister of the lines of communicafion of the Russian Empire etc. etc. The export of perishable foodstuffs is continually developing, and plays a considerable part in the material progress of a country. It is sure to increase considerably, especially if a good organization of cold storage trans- portation comes to the aid of the manufacturers of the country. The development of international commerce has good results on the finance of a producing country, and allows of paying off foreign loans more quickly. -*. In the case of countries which are consumers, or which are destined to become consumers, the usefulness of this kind of transportation is not less evident. Thus it is that the density of the population, in the large German towns, for instance, makes the study of transportation and the improvement of its facilities so important. It should be borne in mind, in fact, that Germany finds it actually necessary to import annually (1908) from abroad: 325 million francs worth of meat and animals. 287 } X) X » fowls and eggs. 125 X) > > * vegetables and fruits. 950 X X) X * grain and cereals. Or a total of one thousand six hundred and eighty seven millions of francs worth of perishable products, the great majority of which would derive great advantage from cold storage transportation. And these figures are sure to be increased by the excess of the birth rate over the death rate (Essen 23.6 per 1000 inhabitants, Berlin 8-6, Vienna 75; in comparison with St. Petersburg's 57 and Paris' 1-8). It is evident that countries having large birthrates, in order to safe- guard their financial prosperity, are obliged, not only to create new industries, but to solve the very complicated problem of providing for heir inhabitants, by means which bring the places of production nearer the places of consumption, in order to diminish the cost of transport and to assure the good preservation and the delivery of perishable products in good condition at the most favourable rates. Thus for instance, Germany imports large quantities of eggs from Russia, and Berlin merchants insist on their being carried in special vehicles (Umsetzwagen) without changing on the way. By means of these vehicles the great traffic which traverses Central Europe may be better organized, .938 and fresh fish eggs, vegetables and butter from the north of the Continent and game, meat, milk, etc. may be delivered to the populations in the South and South West of Europe. The International Refrigeration Association, with the moral and material support of the countries, will inaugurate a new era in present day Euro- ºpean economics, and will contribute in a special way to the prosperity of agriculture and agricultural industries. • The prosperity of new industries, as it concerns the application of cold in the provisioning of nations and large armies'), depends principally upon the land (railways, automobiles, etc.) river and sea transportation service, which makes it possible to have rapid carriage of perishable foodstuffs, and advantageous circulation of the capital and of the vehicles etc. engaged in these industries and in transportation work. According to Dr. H. Viry, psysician-major of Class 2, the transportation of chilled meat in times of peace, and of frozen meat for the army in war time offers the following advantages: *) According to the new regulations for the provisioning of the army in time of war in France, February 15the 1909, and in Austria Hungary (Verpflegsvorschrift) the conditions under which both men and horses may be placed in time of war are so variable, that it has been found impossible to draw up fixed rules, or to give formal orders. Also, the commanding staff apa the administrative service should determine the measures to be taken, by being completely informed on the state of affairs at the time, and judiciously availing themselves of the different means to which they can resort (refrigerated transportation among others). It is indispensable that the officers and officials of all degrees in the state should be well acquainted with the principles and practice of the running and service of all the railway and navigation lines, and the applications of motor traction (refrigerated vehicles) to the provi- sioning of the forces. For instance, in the course of the recent French manoeuvres in 1909, the motor vehicles borrowed from the omnibus company of the City of Paris, conveniently arranged for carrying fresh meat, showed themselves capable of rendering very great service. Their conveying capacity when they are altered may be 1500, 2000 or even 2500 kilo- grammes, their rate of travel being reduced from 18 to 14 or 12 kilom. per hour. From the favourable results given by this experiment, there are measures under discussion, in the next transaction about to be concluded between the City of Paris and the Omnibus Company, for the 800 motor buses which the company is about to dispose of, and which will be required in case of mobilization, to be built so that when the carriage body and accessories have been removed, these vehicles may have built upon their chassis a body of the desired capacity, for the carriage of fresh meat. º The bodies will be built at the expense of the military authorities. On mobilization, 15 motor buses would be required for each corps, or 3 per division, and three for the undi- vided parts. The use of these vehicles would allow the regimental meat wagons to be dispensed with, and the inconvenience of their large numbers has often been spoken of. In Tunis, long automobile roads (the remarkable work of the French protectorate) such, for instance, as the Souse-Sfax Road, 128 kilometres in length, are available for the defence of the country, and as feeders for the great railway lines. - The regulation of relief services requires the greatest amount of initiative, a spirit of foresight always on the alert, and a full sense of responsibility. The new regulations of Austria Hungary deal in the same way with modern means of transportation, the railways of the country and motor conveyance. It provides for the exten- sive use, no doubt in the near future, of the latter, which will evidently offer the most satis- factory solution of the problem of provisioning in time of war; as the French manoeuvres have demonstrated. •S In order to effectively carry out all the technical and administrative orders relating to the revictualling service in time of war, it is necessary to be acquainted with, and to make good use in times of peace of the documents relating to the traffic in, and concerning the control pſ, the use of rolling stock travelling along the lines of home or foreign systems. 939 1. The disappearance of herds following the troups on the march, that is to say, the disapearance of distemper, the risk of infection from the ground at the halting or meeting places, of the encumbrance on the road and railway, of forage and dead weight, or an economy in money, trains , and men. . -- - * 2. The facility of rapid revictualling by rail or road transportation, and the certainty of arrival, in time and in regular quantities. - * 3. The reliability of the quality of the meat, provided by healthy animals, carefully slaughtered instead of the tired, ill, badly nourished, hastily killed, which are inevitably provided by the army herds in war. To assure a regular supply of meat to an army of four corps (say for six days rations), 440 carts would be necessary to carry live animals, and 43 would be required to carry frozen meat. The goods wagon (carrying 10,000 kilogrammes or 33.000 rations), acts as a reserve in time of war. The International Refrigeration Association has as its object the collecting of all the results and information tending towards improvement in the existing rules and regulations relating to international commerce in refrigerated products, and the feeding of nations and large armies. For this reason the third question of section five, & Application of Cold to Transportation, enquires as to the practical means of refrigerated wagons passing frontiers where the railways are interrupted by a difference in gauge. - Actually, in order to avoid changing the goods from one wagon to another, necessitated by the difference in gauge of the railways at several frontier stations in the west of Russia, (Prussia and Austria-Hungary), special wagons are being tried, whose axles may be converted, that is to say, a truck having a Russian body is fitted with Prussian axles, and the body of a Prussian truck is fitted with Russian axles, and they continue their journey without transferring the goods. This change of axles is effected in a few minutes and with the greatest safety to the running of the trains. This system of axles may without doubt be applied to the special refrigerated wagons intended for international commerce in perishable foodstuffs, on the international rail transportation routes of Europe and Asia, without the necessity of changing wagons'). It has been stated that cold, by its applications, has brought great changes in the economic conditions of Russia, thanks to the combi- nation of the cooperative Societies of peasant producers of butter exported abroad from Siberia, to the control of the running of special wagons on the fast trains, and to the sailing of ships and boats in the Baltic Sea. In view of question 2 of section five of the Vienna Congress 1910, “Necessity of uniform regulations to facilitate the running of special *) The advantages accruing from this system to commerce, and the administration of transportation work are pointed out in the journal ,,2eitung des Vereines Deutscher Eisen- bahnverwaltungen" Nr. 73. September 29th 1909, ,Verkehrsfrage der Güterbeförderung in Umsetzwagen,“ vom Regierungsasessor Dr. Rehs, Posen. 940. wagons,” Russia finds it advisable, in national and international traffic, to introduce a list of statistics based upon the journey form (bulletin de par- cours), which accompanies each vehicle'). - These journey forms used in Russia since 1907, give a complete summary of the data necessary for reckoning up the work of the wagons, thus considerably simplifying the work (writing) of the stations, and counting offices, and lessen the cost of enquiry into the work done by the rolling stock. The control of these vehicles may be centralized by the office of the International Refrigeration Association, or by controlling offiices and train despatchers of the transportation companies, after receiving the vehicles at their destinations. These controlling offices could then draw up tables of statistics from the journey forms by means of an adding machine”) and give them in to the International Refrigeration Association, which would then draw up a table (inclusive) of statistics for the whole system. º This complete table makes it possible to compare the business of different lines over land (mechanical traction, automobiles etc.), river and ocean lines, serving the same markets of production and consumption, and in national and international traffic, also to compare accounts of perishable merchandise carried, the quantities of rolling stock (with or without refri- gerating apparatus) used by these lines, the distances travelled and the times of these special vehicles, their speed, the regularity of transportation the time of idleness of the vehicles and steam boats, delays in delivery, the loads, the gross receipts and the statistics of the transport companies, upon which commerce in perishable merchandise and the revictualling of large armies depend. w - The advantages of the new process”), which, besides being approved of in Russia, has been approved of in France and in Austria-Hungary by Regierungsrat R. v. Loehr in the “Österreichische Eisenbahn-Zeitung, No. 6, February 20th 1905, where among other things, M. R. von Loehr says: *I have repeated the contents of the article as completely as possible, because the importance and necessity of the soonest possible introduction of the system into general international traffic can not be too often in- sisted on for all those concerned therein. » The General Office of the Hungarian State Railways now publishes, in accordance with an international agreement, a special pamphlet,”) furnishing 1) See the annexed tables and regulations Nos. 1, 2, 3, 4, 5 & 6. *) For instance the Burrough system of automatic writing in a table of 6 columns, each running to nine figures. * 3) See the General Review of French Railways (Revue Generale des chemins de fer francais) December number 1904 and March 1905 a Statistics of International Transportation", by General A. de Wendrich. 4) Orientierende Úbersicht direkter Güterbefórderungskurse für Eilgüter, Viehtransporte und dringliche Wagenladungen von Ungarn nach Österreich, Deutschland, Belgien, den Nieder- landen, nach der Schweiz und nach Frankreich, ferner für gewöhnliche direkte Wagenladungen von Ungarn nach den oben angeführten Ländern, und umgekehrt, gültig vom 1. Mai 1909. 941 detailed information upon the methods of communication employed to eſfect the despatch of goods as quickly as possible, also as to the relations of foreign countries holding to the same agreement, the stations of destination and the merchandise sent into and out of the country. - In order that it may be brought about in practice, that transportation, especially that of goods subject to deterioration, may be really carried out according to the orders published in the pamphlet mentioned above, the Hungarian State Railways and the foreign railway companies send out *) Dann können die Wagenverwaltungen leicht ein gewisses aktives Kontrollrecht tiber die Benūtzung ihrer Wagen auf fremden Bahnen ausūben und Wagenablenkungen feststellen, was jetzt kaum ausführbar ist. - 942 These statistics *Statistik des Verkehrs auf den deutschen Binnen- wasserstraſsen» are intended to ascertain: «To what extent the transfer of goods from rail to water, and vice ºversa takes place.> This could be obtained by our table No. 2 appended hereto, based upon journey form No. 1. • The statistics drawn up in Hungary do not include the direct transshipment to navigation traffic. From this it may be gathered that the journey form has not been introduced in the case of boats sailing on the waters of the interior. During the session at Copenhagen in 1907 of the International Institute of Statistics, the Danish shipping companies approved the journey form for steamboats, and the inspectors of bridges and roads in Belgium and in France, have also approved the form proposed by M. A. de Wendrich'). Con clusion. * Considering the necessity of contributing to the progress of refrigera- tion and of protecting the refrigerating industry to facilitate providing of food for nations and large armies it is desirable: 1. That the Second Refrigeration Congress at Vienna 1910 should under- take the formation of a statistical committee under the council of the International Refrigeration Association. * 2. (a) To elect members of this committee from among the members of the-council of the Association, with the approval of the administrators of transportation companies and refrigerating industries, which would keep up with all the progress made in these directions, (b) to elect a Paris secretary of the committee. 3. To adopt a system of statistics based upon the journey form which accompanies each vehicle, as recommended by the International Institute of Statistics. º 4. To collect from governments and administrations information concer- ning the running of the rolling stock conforming with international conventions and concerning the through trains, used to enable the vehicles to travel quickly. 5. To collect the reports of this committee together with those of the transportation companies and the publications made, which would be in charge of the council of the Association. 6. To give information, by means of the journey forms and tables annexed hereto,”) on: * a) The business transacted by the different lines (land, river and sea) serving the same markets of production and consumption, in national and international commerce. 1) See the report presented by M. A. de Wendrich in Paris 1909 to the International Institute of Statistics. 2) Nos. 1, 2, 3 and 4. (These tables appear on pages 8, 9, 10 and 11 in the french paper, and should be inserted here.) - * º g 943 b) The loads in tons 6f perishable products. - * * - * c) The distances travelled by wagons full of merchandise and empty, in national and international commerce. d) The amounts carried by the transportation companies and their record. f) The time spent by each vehicle. g) The net speed in kilometres per hour of each vehicle (including stoppages). h) The use of special vehicles with convertible axles, necessitated by differences in gauge. ... • i) The influence, if any, of syndicates and trusts on the transportation of these goods. 7. To assure a rational use of all the means of transportation, and an advantageous circulation of the capital invested in refrigeration and transportation companies by suggesting improvements in the rules and regulations relating to international commerce in perishable products. Regulations on the keeping of journey forms in Russia. 1. For each vehicle, loaded or empty, to whatever train it is attached, a journey form is drawn up at the station of departure which accompanies the vehicle to its destination. This form should be sent by the station master of the station of departure to the chief guard of the train. 2. The station agents of the stations. a) of departure, b) of destination, 3) of call, d) of changing the train (caused by damage or loading etc.) and of changing the numbers of the trains fill in the form with the required information. 3. For loaded vehicles — the station of destination indicated on the journey form is the station for which the goods are destined. If the goods contained in the vehicles are addressed to several stations, only the last station is to be put down. For empty vehicles the station of destination is that to which the vehicle has been ordered to be sent. If the vehicle is addressed to a railway line, the station of destination is the connecting station. At this last, after the reception of the vehicle, new forms are not made out, but the definite destination is indicated upon the old one, after having filled up the right columns. w - 4. The journey form is divided by black lines into several horizontal sections. The first division is intended for notes at the station of expe- dition, the remainder for those at the stations along the line, and the last, for those at the station of destination. 5. The time of arrival of the empty or loaded vehicle at its desti- nation is marked upon the journey form, which is then considered completed At the same time a new journey form should be prepared for this vehicle in which columns Nos. and 12 and especially No. 3 (time of 944 arrival of the vehicle at the given station) are filled up. This new form is kept at the station until the vehicle leaves this station. # 6. The journey form is not finished at the station of destination except in the case when the goods, from damage or any other cause, have to be changed from one vehicle to another. In this case, the time of detaching the vehicle is indicated in the journey form accompanying this vehicle, and the reason of this is indicated in column 9, after which the form is considered as completed. A new journey form is immediately made out according to the directions in para- graph No 5, and waits at the station office until the vehicle is sent off after being repaired. The vehicle into which the goods are changed, is accompanied by its journey form, delivered at the changing station and having in its top left hand corner the following: «goods transferred from vehicle No. . . . » 7. The vehicles sent to the workshops to be repaired have their journey forms completed at the station adjoining the workshops by a note in column 9 showing that the vehicle was sent to the workshops. A new journey form is then immediately made out for this vehicle; this is kept at the station office until the vehicle is repaired and sent away again to a new destination; in this case the time of arrival of the vehicle at the workshops is noted in colums 3 and when the vehicle leaves the workshop column 9 is filled in to this effect. "Nº. 8. The chief guard of the train is obliged to conform with the follo- wing regulations. --- a) When the train arrives he must ascertain that, for each vehicle, a journey form has been sent whose number corresponds to that of the vehicle. b) In case the station insists on receiving the train without the forms, or these are lost by the guard himself, the guard must immediately advise the Superintendent of the line by an official report, and send a copy of this report to the head office of the General Ad- ministration of the Empire. This report should contain information as to the numbers of the vehicles, the stations of expedition and destination. Besides the guard of the train must demand at the first stopping station new forms to be drawn up for the rest of the route giving information to this effect in column 9. 9. The stationmaster of the station where the form is completed immediately sends this in a separate envelope to the head office of the General Administration of Railways of the empire. 945 Second International Refrigeration Congress Vienna * (6th to 11th of October 1910). PROGRAMME of the Commission on Transportation by . M” Richard Bloch Chief-Engineer of the Orléans-Railway Co. given in the name of the International Commission of Transportation of the International Association of Refrigeration º VIENNA 1910. 60 947 Second International Refrigeration Congress, Vienna. w (6th to 11th of October 1910). -* Programme of the Commission of Transportation. 1st Question: The present system of running refrige- rated wagons on the various European and American lines. 2nd Question: The necessity of uniform regulations, to - -- facilitate the running of special wagons. 3rd Question: Practical means of running refrigerated wagons over frontiers where the railway line is interrupted by difference in gauge. Being entrusted with reporting on the 3 first questions of the programme of the 4th commission of the 2d International Refrigeration Congress, it seemed to us that these three questions are too intimately connected with each other for it to be advisable to make 3 distinct reports; we leave there- fore combined all these questions in the single report which follows. Perishable foodstuffs naturally suffer from staying in wagons of the ordinary type, when these prolonged periods leave the meat exposed, in summer to the heat which concentrates in the vehicles; in winter, to the frost which penetrates the walls in spite of all openings being closed. The heat is especially formidable, and for several years attempts have been made to minimize its effects. Thus one has been constructing more and more special bodies for wagons intended to carry this kind of goods, having double walls and double roofs, aired by means of ventilators consisting of shutters provided with longi- tudinal and lateral faces. The wagons are often painted white so as to increase their resistance to outside heat. - This type of wagon is most common in France, especially upon the P. L. M. and P. O. railway systems, and in Italy upon the Italian State Railways. Moreover, on these last, which serve particularly warm districts, the ventilation of the wagons is completed by special ventilators called torpe- does placed on the roofs of the wagons, which allow of the air in the 60% 948 interior of the wagons being changed in 100 seconds, when the wagon is travelling at 60 kilometres per hour. - But in the transportation of these products, the distance of which is extending more and more, these various methods are insufficient remedies; there is, besides, the traffic in particularly delicate goods, such as fowls and small dead animals, which cannot be practically carried out with ordinary rolling stock, and for which the transportation of live animals must be substituted, in spite of its great inconvenience. This is why, if one may judge from the attempts which are being made everywhere, the ideas of the administrations of railways seem to tend more and more towards the adoption of refrigerated wagons for these long journeys. They are moreover encouraged in these views by the remarkable results obtained with this special rolling stock upon the railroads of the United States, where more than 60,000 of these wagons are running, and nearer at hand, on the Russian and Siberian railways, where this traffic has recently made the most astonishing progress. Nevertheless in this country and in other European countries, a too hasty adoption of these methods must be guarded against. The United States and Russia with Siberia occupy portions of conti- nents much larger than Europe. The United States in particularly have a large population unequally distributed over very dissimilar districts, from tropical Florida to the frozen lakes on the Canadian frontier; from California, where the climate is particularly suitable for the cultivation of early vegetables and fruits, to New York where extremely severe winters succeed tropical summers. In districts which differ so greatly changes must take place, and, because of the long distances over which goods are distri- buted to the populous centres, the refrigerated wagon has been, and still is, a necessary and indispensable accessory with which to deal with these changes. * In Europe the difference between the climates of the various countries, for instance between those of Naples or Seville and St. Petersburg, of Hyères or Nice and Berlin, certainly shew variations comparable to those mentioned above; but it must be remembered that the United States are inhabited by a homogeneous population having the same language, customs and laws, and that there no customs barrier whatever hampers the circula- tion of people and goods; Europe on the other hand, is divided into a large number of different countries, where this circulation is hindered by the differences in languages and customs, by the variety, or the absence, of regulations, by protective barriers, and even by differences in the gauges of the railways as in the cases of Spain and Russia. It is undoubtedly for this reason that the use of refrigerated wagons has, up to the present, only been attempted in a half-hearted way, attempts being limited and kept to the interior of the different countries, , and gene- rally giving very little encouragement. * 949 Temp é 1 , ture 33o 432o 31° 3 Oo 29o 289 27o 269 25o 24º WAGoNS RÉFRIGÉRANT S. Mois de Juillet et d'Aoüt 1906. éennes 15 —* août A V.- Juiiiet 2 3 4 5 S 7 8 S t 5 6 7 8 s 1ou 12 15 laisiens s2oz1z22szazszszſzszsoo3u2 5 4 5 6 7 8 9 10 11 l2 ls 14 15t6 tr 18 19202uzz2334252627282930 23 Y -- 950 On the other hand the use of these vehicles has succeeded in Russia and Siberia, where the same favourable conditions of space and homo- geneousness of population and administrations are found as in the United States. * • * - Besides the restraints existing in each of , the European countries, it may easily be seen that there is not much scope for transportation by re- frigerated wagons. The relative shortness of the distances, the smaller dif- ferences and irregularities in temperature, the distribution of traffic resulting from the density of the population, are so many influences limiting the development of this new method of transportation. It is, in fact, evident that commerce has little wish to undergo the expense necessary for the use of refrigerated wagons for journeys which take place for the most part in one night, and in the coolness of the night. On the other hand a very appropropriate example goes to show the very real seriousness of the difficulties resulting from variations in temperature. The graph, on page 5, in fact, represents the daily variations in the height of the thermometer at Paris for the period from the 1st of July to the 31st of August 1908, and the variations during the same period, in the tonnage of meat carried to the Paris station of the Paris—Orléans Railway, by a daily service of refrigerated wagons arriving at that station. . The fact that these two lines are almost parallel is very significant; it shows that the consigners, before sending out each daily batch, carefully consult their thermometers, and, according to the results of this consultation, they either despatch their goods in refrigerated wagons or in ordinary wagons, that is to say, they either undergo or do not undergo the expenses of refrigeration. s - It is evident, that, with such irregularity in their daily work, such daily services can hardly be successful, even if they continue to exist. - Besides, this irregularity also results in the scattering of the traffic; the small consigners who act as we have just seen can not do so from day to day, without losing sight of the general interest which they would have in sustaining, by the permanence of their custom, a system which is very advantageous in the hot season. Also the results obtained are very mediocre, and the tonnage of meat carried in refrigerated wagons to the Paris Orléans station although it is of some importance only represents a very small fraction of the total tonnage of the whole traffic. t In spite of a reduction of 5"/o in these transportation rates, the Com- pagnie du Nord français has also had but insignificant results in the carriage of fish over the short distance separating Boulogne from Paris. With the similar results which are reproduced in a small way, near by in other countries, we can not be surprised if the railway systems of Europe, with the exception of Russia, can only show the small numbers of wagons in the following table, as against the 60,000 of the United States. 951 Refrigerated Wagons Railway belonging to Observations and notes on Rail- Private * | the goods carried ***- ways Owners Total Alsace-Loraine . 12 13 || Meat carried between - Holland and Switzer- - - land Wurtemberg . 7 7 || Two milk wagons and i five butter wagons Baden . g 10 || 10 Vegetable fats Prusssian 113 114 227 63 milk wagons, 146 butter wagons, 16 | fish wagons, 2 meat wagons Oldenburg . 12 12 || Fish Bavarian . 152 152 || 2 butter wagons Belgian 20 20 || Ice and eventually fish Austrian'. 156 156 || Meat, excluding 857 beer wagons of which ~ 781 are private South Austrian' . º 2 2 || Fish Hungarian . 148 65 213 Meat South East Russia . 10 10 || Meat | | Moscow-Brest. 17 17 Warmed in winter | South Russian 27 27 19 for fruit, 5 for beer, 2 for creamery pro- ducts, 1 for dead fowls Moscow - Nijnyi- Novgorod 18 18 || Warmed in winter Trans-Caucasian 23 23 Milk and fruit Egyptian - A few Milk and fruit Norwegian A few º Milk and fruit Dutch . 8 * ... 8 Butter Italian . . 69 69 47 for butter and - cheese, 9 for meat, 13 for beer French State Rail- ways . . . || 13 x || 17 xx 30 || x butter and meat, xx butter French Railway Com- - panies . • . Îl 72 72 Meat, fowls, butter, || fruit and fish Total (excepting Si- | . . . beria) . . . . . || 712 || 373 1085 952 This table immediately shows up an interesting fact; this is that the railways undertook the providing of these wagons specially in the countries where they were best' armed, by regulations and the general public attitude, . against the claims which would undoubtedly arise from refusal caused by a numerical insufficiency of special rolling stock. Besides, a useful conclusion may be drawn from the interesting fact that in the various countries refrigerated wagons are especially employed for the carriage of meat, butter and fish, permantly and almost constantly produced, and which may be relied upon for the regular employment of the T 60 000 1300 Wagons i anoco" As º en9 y Ra 1990 of veos t- elascº º or \scwº cºi ‘o cº cº * #_* f t- ; 3 * T tº- º: A 20,000 5 gy, '506) cº _* s º g º * 400 T A Tº 000 *2.f º 300 grº - § tº 8,000' p- y ‘e 3 & à 200 T {- {- C. ur .." s # 000 tº .* 's º § § – * * * : - 390 * CE *— _-T . . . . .” U O } ~ * | Q \894. 95 90 g’, 98. 99 1800 01 62. 03 O4– O5 06 U7 service of refrigerated wagons, more than fruits and vegetables, the traffic in which is irregular and periodical. The above statement does not include the Siberian rolling stock, because the progress of this special means of transportation on the railway systems of that country is very instructive, and for this reason deserves special explanation.*) & It was in about 1894, after the construction of the Trans-Siberian Railway, that butter began to be exported from that district, but it did not assume any real importance until the Russian Government wisely undertook to come to the aid of this new industry by a whole series of special *) The statements which follow here are extracts from the transactions of the Russian Committee at the International Refrigeration Congress at Paris in October 1908. 953 measures favouring the establishment of cold stores, and the organization of transportation in refrigerated wagons. ‘s. Of recent years, for instance, it has authorized the importation free of duty of about 7000 tons of refrigerating machinery. At the same time the stock of refrigerating wagons for the butter export traffic alone has, from the care taken by the Government, increased in effective number to the following figures: 1898 . . . . . . . . . . . . . . . . . . . 0 1899 . . . . . . . . . . . . . . . . . 50 1900 . . . . . . . . . . . . . . . . . . . . 100 1901 . . . . . . . . . . . . . . . . . . . 370 1902 . . . . . . . . . . . . . . . . . . 866 1906 . . . . . . . . . . . . . . . . . 1050 1907 . . . . . . . . . . . . . . . . . . . 1292 of the 1862 refrigerated wagons existing in Russia. To supply these wagons, along the lines, ice depots are set up, the number of which has increased from 18 in 1898 to 42 in 1900, and to 77 in 1907, having a total capacity of 150621 cubic metres, and so arranged that their distances apart do not exceed a maximum of 264 kilometres; the reduction of this maximum to 170 kilometres on the Trans-Siberian Railway allows the ice to be renewed twice a day. This system is completed by ice stores built at the principal despat- ching stations, viz: Ob, Kainsk, Omsk, Petropavlovsk and Kourgane, intended to hold the butter awaiting despatch. Lastly cold stores constructed by the State, or by private companies, at the principal ports on the Baltic store the butter awaiting shipment. Without entering into the technical details of the construction of these wagons and stores, it is interesting to note that the net cost of refrigeration by means of ice wagons including all the expenses of wagons and depots, and the interest and amortisation of first cost of establishment, reaches de- finitely 0.81 kop. per poud (1661 kilogrammes) for each day's refrigeration, that is to say, 0.91 francs per ton per day, or 1258 francs per ton for the whole journey to the Baltic ports. This plan taken altogether, so generously conceived and rapidly carried out in spite of the trouble caused by the Russo Japanese War, has had decisive results, as is shown on the accompanying graph. where the progress of the export of Siberian butter is plotted against the increase in the effec- tive number of refrigerated wagons during the same time. This result, which does great credit to the Russian Administrations, conclusively shews that, for these long distances, the employment of refri- gerated wagons is necessary to the progress and even to the existence of a traffic in perishable products. 954. Admitting this conclusion, and recognising the advantage of this progress to the well being of the inhabitants and the railways, it will be as well to investigate all the means which may facilitate the running of this kind of stock. - - This investigation evidently need not be made in the case of the United States, where under the pressure of necessity, because of the long distances over which foodstuff must be carried, and thanks to the uni- formity of customs, language and laws prevailing over an immense territory, this kind of transportation in refrigerated wagons has made remarkable progress, and now only requires care in arrangement and detail. The attention of Europe should be called to this point of view. Now Europe, divided, as it is, into nationalities, is very far from offering condi- tions as favourable as those of the United States or of Russia and Siberia. We have just seen that the future of transportation in refrigerated wagons is on international ground; it would appear very difficult, in this state of things, for international services to be inaugurated by the uncombined efforts of the various railways. - It should rather be hoped that its coming will bring about the for- mation of an international society which would be to this mode of trans- portation what la Société Internationale des Wagons-Lits (The International Sleeping Car Company) is to the carriage of passengers. * Besides, it seems generally recognised that the providing and the exploi- tation of these special wagons should not be done by the railways themselves. Thus in the Administrations of the Prussian State Railways, the Hun- garian State Railways, of the Trans-Caucasian, which do possess refrigerated wagons, in the Italian State Railways, and the French Railway Companies it is thought that private owners are better than public administrations for choosing appropriate rolling stock, for the superintendence and the special care which is necessitated for instance by the variety of temperatures under- gone by the different products, and for finding and keeping the scattered agricultural customers who are naturally prejudiced against novelties. Besides, an inference singularly conclusive, from the double point of view of the greater success of private enterprise and the advantage to the public, may be drawn from the simultaneous services of refrigerated wagons which serve districts on the French State Railways and the French Paris Orléans Company, practically alike and situated along two lines very close together each of which go from Paris to Bordeaux. In fact, although the official service of the state only requires an extra 10% on its rates, while the private company requires 15"/o according to the statements made in July 1907, the wagons running on the Paris Orléans travelled to Paris with an average load of more than double that of the State Railway Wagons, * The railway administrations shoulſ, then be asked, not to make any immediate intervention in the refrigerated wagon services, but to limit them- 955 selves to facilitating the formation of special societies, especially an Inter- national society, and this not only by offering their good will, but especially, -and this is very important, by preparing the ground beforehand for the working of these societies by the establishment of uniform regulations, favourable to the international running of these wagons. As a matter of fact their present regulations for the interior are very different; to give a very impartial example, and also to establish a basis for the eventual revision work, we are adding in an appendix to this report, a synoptic comparison of the conditions enforced by express tariff No. 121, recently drawn up for these special wagons after an exhaustive study of the subject by the French administrations, with par 35 of the German tariff, and lastly with the regulations of the Italian State made on the fourth of April 1908, both of which are applicable to privately owned wagons. It is, unhappily, found from this comparison, and from information gathered from neighbouring administrations, that the ground is at present very badly prepared for any future refrigerated wagon companies. It is evident from the very first that they can only exist by means of charging their customers rates specially increased above the ordinary railway rates; but almost everywhere the competition of the railways makes the establishment of these rates, and hence that of the services themselves, almost impossible. In fact in Germany, in Belgium, in Hungary, in Russia and in Norway, refrigerated wagons, worked in a limited number by the administrations more experimentally than otherwise, are placed at the dis- posal of the public without any extra rate. Moreover in Austria, where the Austrian State only requires the public to furnish the ice, in Holland where the Dutch State requires an extra rate of 4 francs per ton, in France, where the French State requires a rate of 10°/o, and lastly in Siberia, where the extra rate for the entire journey to the Baltic is only 1 Kop. per poud, while the actual cost is 7-12 Kop., everywhere the rates are obviously below the actual expenses. All service deserves payment, and these concessions can only be satis- factorily explained as being of an experimental character, which seems to be the case almost everywhere on these services up to the present. Doubtless the losses occasioned by these modest attempts are of little importance, insignificant as they are in the general mass of the work of the railway; but while their unimportance often renders them useless from the point of view of the general advantage, they may perhaps be detrimen- tal to the general interest, because their competition hinders the establish- ment of the private services, which are best suited to the various exigencies of the different railway companies, and which seem in fact to be more appre- ciated by the public, as in the case of the French State Railways. To provide for the future from this point of view, and to allow of the establishment and success of international services, it would seem oppor- tune to ask the railway administrations to cease giving these abnormal 956 favours, and to require fair remuneration from the public for this special work. - Or even if it appears impossible to retract from their present position the railways might then deduct from their receipts the amounts necessary to properly remunerate the private services, who in place of the railways undertake transportation in refrigerated wagons, which everyone recognizes as particularly expensive. - But in the present state of the regulations this solution appears equally difficult of realization. - In a general way, when the railway deems it expedient to allow the running of privately owned wagons, and if these wagons take the place of their own rolling stock, and allow them to economize therein, it would seem very fair to take account of this economy, and allow some payment to the proprietors of these private wagons. * But the German regulations do not allow any payment of this nature, and the Italian regulations only contain a rather uncertain provision relating to this matter. Moreover the Austrian State imposes on these wagons a minimum journey of 5000 kilometres per year, and the wagons must be loaded on the Austrian railway system, and requires from the owner a compensation of 2 heller per kilometre wanting. Allowances are only made on the following systems: The South Austrian, which grants an allowance of 200 crowns per wagon per year. The Hungarian State, which allows 1.8 heller per kilometre for wagons which may be generally used, loaded or empty, when the distance travelled annually exceeds 10,000 kilometres and does not exceed 20,000 kilogrammes. Lastly, the French administration which allows 0.03 francs per kilo- metre for refrigerated wagons on express goods trains loaded or returning empty; and an allowance of 0.045 francs is made (temporarily) by the Orleans Company. --- Keeping these two very important points in view, without going into a detailed analysis of the other questions, it can be seen that the desired agreement could not be realized without difficulty. It is, however, an in- dispensable agreement and the proceedings of the International Association of Refrigeration should be followed with this end in view, if any appre- ciable result is to be obtained, and if any progress is to be made in a direction which may be rich in new traffic. It is only after having settled these two fundamental questions, and having thus made it profitable to study the great international transportation, that the detailed examination of the regulation of these may be usefully approached working together with the railway administrations. For this examination and these negotiations, the special express tariff of the French railways No. 121, which we append hereto, appears to form 957 an excellent basis. In fact we believe it is the only tariff which exists on European railways, for special transportation in refrigerated wagons; it is in every way a very complete document, whose well thought out provisions have the sanction of several years of practice. Concluding, the special attention of the administrations involved must be called to measures to be taken to facilitate the transit of refrigerated wagons over the frontiers of Russia and Spain, where the difference in gauge creates a special and serious difficulty. § Already methods of effecting a change of axles, allow of the transit of numerous slow goods wagons over the Russian frontier without disturbing their loads. In Spain the royal orders have just authorized the application of these systems to the Franco-Spanish stations of Irun and Cerbère. It is to be hoped that, with the active assistance of the administrations of the railways interested, these applications may be soon extended to the transit of express goods wagons carrying foodstuffs, and especially to that of refri- gerated wagons. Rich a r d B 1 O ch Chief Engineer of the Orléans Railway Company. APPENDIX. * * 960 A Synoptic Table of the Provisions Regulating the Running - - - ; by FRANCE Special tariff for the general express service No. 121 The Railway Administration admits for transportation on its own service and on the general service, under the conditions set forth in express tariff No. 121 mentioned above, the products named in art. 15 on the conditions of application of the general express tariff. Refrigerated wagons must be admitted one of the six great French railway companies, by the administration of the State Railways or by the administration mitted on to the French the whose stock is ad- these or companies of a foreign Railway system ; entries render the persons in whose name they are obtained respon- sible to the railway administrations for the empty, the upkeep, and siding etc. of refri- gerated wagons. Plans of the vehicles and their wor- king conditions should be submitted for approbation to the administration on whose admission, running loaded or France G E R MA NY Regulation of railway traffic (Pard 35) Def #2 The following only shall be ac- cepted for transportation in privately owned wagons (such wagons): as reservoir . . . merchandise which, by reason of its nature, requires a wagon specially constructed or specially fitted up. Entering Wagons – Conditions - the system entry is desired. Refrigerated wagons should carry, side, inscriptions indicating the of the persons or companies who have obtained their entry, which has on each Il:ll IſleS the name of railway accepted them, the name of the station at which they Privately owned wagons are wagons specially ſitted up for the transportation of certain goods, the use of which is reserved to the owners designated by inscriptions on the wagons. The establishment of these wagons should be authorized by the administra- tion which accepts them rolling stock. among their .961 of Refrigerated Wagons Belonging to the Public, in Germany, and Italy. . & - *mmss-mm IT A L Y & - | Regulations for privately owned wagons R E M A R K S running on the State Railway Lines *. -*- - - n it i on s. Privately owned wagons can only be. used for the goods marked on the outside; except by the special permission of the admi- nistration. Owners may use their wagons, while running empty, for the transportation of empty boxes and receptacles, on payment of the rates set out in the tariff in force, without applying the minimum quantities set out for them when full. But privately owned wagons used for this purpose would be considered as running empty for the discount for running empty which is indicated below. of Establisment — Reception. Privately owned wagons are those which, belong exclusively to the public; they are, i however, considered as such when they are hired from the railway administration, or from . other owners, and the owner of which may dispose of them without any restrictions. Hence, as far as this regulation is con- cerned, the hirer is always considered as the owner of the wagon. Privately owned wagons are distinguished from those belonging to the railway by carrying, besides the name of the railway, that . * - of the owner and that of the station to t which they belong. Those admitted to the State * Railway yards carry besides a number between 900,000 and 989.999 followed by the letter P in brackets thus P. * As a rule the State Administration only admits on its sidings privately owned wagons specially constructed for the kind - | 61 962 F R A N C E GERMANY Regulation of Railway traffic (Para 35) Special tariff for the general express service No. 121 are kept, their tare weight, maximum loads, a number and, if necessary, the kind of transport for which they intended. are specially Refrigerated wagons, whose tare ex- ceeds 12.500 kilogrammes, are subject to an extra rate as indicated below. Refrigerated wagons are only enrolled and allowed to run after their acceptance by the contracting administration to which they are presented. The right of refusal is given, in case of dispute, to the latter. Empty wagons are run on slow goods trains and charged on the outward and return journeys according to the following table: the rates in Up to 200 km 0-10 francs per km 200 m 300 a 0.06 a 7, 20 300 m 400 , 0.05 m 5, 7, Above 400 m 0.02 , y; 7) The loading and unloading of refrige- rated wagons is done by the consigners and the consignees on station platforms specially set apart for this purpose hy the station- masters. Therefore there is deducted, from the cost of transportation, which includes extra charges, a sum of 0.30 francs per ton for each time a wagon is loaded or un- loaded. 1. For the express service the charges are made according to the following table : T r a n s p or t a ti on N e- Empty private wagons are charged when they go to the workshops or sheds: (0.07 marks per kilometre per axle plus a fixed charge of 2 marks.) Up- According to the arrangements in the tariff, the upkeep of the entire wa- gons rests with the consigners and the consignees. The R at in g of Empty privately owned wagons are transported free of charge. 963 Regulations for privately owned wagons running on the State Railway Lines R E M A R K S of goods and the manner of transportation for which they are intended; however, under excep- tional circumstances, wagons may be admitted which do not answer to the above description. c e s s a r y for Rep a ir s. Empty wagons are run free of charge over an annual distance equal to that over || which they run loaded. For any distance run empty in excess of this (which is the case here), 0.075 francs are charged per kilometre for each wagon. ‘. kee p. The upkeep of privately owned wagons rests with the owners of these wagons, except at those stations or ports where this upkeep is left to the railway, as in the case of customs stations. f No reduction of the tariffs is made. E m p t y W a g on s. 1. For slow trains the wagons are run free of charge over an annual distance equal to that over which they are run when loaded. | 61% 964 - *- F- FRANCE Specialtariff for the general express service No. 121 *- -------aw-s-sessºrsº--º-º-º-º-º-º-º-º-º-º-º-º-º- G. ERM A NY Regulations of Railway traffic (Par 35) * Up to 200 km . 0.20 francs per km 200 }} 300 a . 0°12 }) }} 35 300 x 400 a . 0-10 a }} }} Above 400 7) - 0.04 }} }} 37 2. For slow running no charge is made. Foodstuffs carried in refrigerated wagons are charged according to the express tariffs, or the slow service the refrigerated wagon TUIDS OI]. The charge is based upon the weight of the goods, the minimum weight being 4000 kgs. For refrigerated wagons whose weight when empty is above 12.500 kgs., the excess of dead weight is charged at a rate of 0-10 franc per ton for each kilometre traversed, in addition to the charge made for the goods. 15.000 kilogrammes, and if the weight The Rating The charge is calculated on the con- signmeut note for the goods transported, the minimum being 2000 kilogrammes per wagon. If the tare of the wagon exceeds of the load is below this figure, one third of the difference between 15.000 kilo- grammes and the tare weight is added to the chargeable weight. If the weight of the load exceeds 15.000 kilogrammes without reaching the tare weight, one third of the difference between the weight of the load and the tare weight is simply added to the char- geable weight. * The weight of all fittings is included in the tare weight of the wagons. {: 2. Carriage of Ice and of Appliances for Main- Transportation free of charge, but the consignee cannot take the ice remaining in the receptacles and the refrigerating appa- ratus on arrivals. Transportation free of charge. 965 -x. **.*. - - • * | IT AL Y # Regulations for privately owned wagons REM A R K S running on the State Railway Lines Any distance travelled empty, excluding this is charged at 0.075 francs per kilometre. 2. For express running the ordinary charges are made as for wagons running on their lines (about 0.20 francs per kilometre for each wagon). of Loaded Wagons. | Goods carried in special wagons are char- On the Western Railway of France ged according to the ordinary railway tariff, the minimum tonnage is from 1700 kgs. with or without reckoning by tonnage, the total || in the express service, to 2500 kgs. charge per wagon and km not exceeding that | on the slow service. On the Paris set out in articles 56 and 57 of the Italian || Orleans Railway the minimum ton- tariff. nage, up to the first of November 4 1909, was fixed at 2000 kilogrammes *. for the express service. In express tariff No. 121 the af | minimum tonnage was lowered up to July 10th 1910: to 3000 kilogrammes for butter transportation, to 2000 kgs. for the carriage of fresh shell fish and crustaceans (Crabs, prawns, cray- fish, and lobsters), oysters and fish. # On the Eastern Railway of France, provided the tare weight of the wagons does not exceed: 10.000 kgs. for four wheeled Wagons, 14.000 kgs. for sixwheeled wagons. taining a Constant Temperature and Stowage of Stock. Transportation free of charge, but a charge is made for the ice which the consignee takes away on arrival. ** | FRANCE F R A N C E age { t * | | t Special tariff for the general express service No. 121 There is allowed, as rent, a deduction from the transportation charge of 0.02 francs per kilometre for each refrigerated wagon, for a distance corresponding to the rate applied to refrigerated wagons, loaded or empty when returning or going to be loaded. Each of the operations of loading and unloading should be effected within a time of six hours. A charge of five francs for each of the three following periods of 24 hours then is made. * 10 francs is charged for every 24 hours after this. The charge made for waiting vehicles is 0.25 francs per day for each vehicle. * G E R MA NY Regulations of Railway traffic (Par 35) Re- No rent is proposed to be paid to the owners of private wagons. St op- There are no restrictive regulations for ordinary periods. Wa i tº Determined by special arrangements. - --- -- -* I TALY Regulations for privately owned wagons running on the State Railway Lines In tS. The principle is admitted of a rent to be paid to private owners of wagons allowed to run on the system, but this rent is left to the discretion of the railway administration, accor- ding to the type of vehicle, its value, its special purpose, the kind of transportation for which it is intended, and the facilities to be obtained from its use. Rent is fixed according to the number of km. charged, and only for the transport of goods affected by the wagons. p in g. Charges for stopping are made after a day of 24 hours, succeeding the arrival of the loaded wagon. This charge for stopping is fixed at L 0:50 for each whole day, or part thereof. in g. RE M A R K S The charge for waiting is fixed L 0.25 per day or part thereof, when the vehicle is standing at the station to which it be- longs, L 0-50 when standing in station. any other On the interior service of the Northern Railway of France, 5 francs is charged for each day of 24 hours or part thereof. The Eastern Railway of France charges: 1 franc for the 1st period of 24 hours. 2 francs for the 2nd period of 24 hours. 3 francs for period of 24 hours. each succeeding PARIS-ORLEANS RAILWAY - G. v. No. 121. Paris, Jan. 10th 1910. EXPRESS GOODS TRANSPORTATION Controller General M. DE LA BORDE Spåtial tariff fºr the GBIOral Express SBTVict, MD, 121. FASTERN, STATE, MIDI, NORTHERN, ORLEANS, WESTERN AND PARIS-LYONS— T-----—- MEDITERRANEAN RAILWAY DISTRICTS. CHAPTER I. EASTERN, STATE, MIDI, NORTHERN, ORLEANS, WESTERN AND PARIS- LY ONS-MEDITERRANEAN RAILWAY DISTRICTS. - The transportation of foodstuffs in refrigerated wagons provided by consigners and consignees or in wagons let on hire by a railway admini- stration and then fitfed up. The Railway Administrations admit for transport, on their own and on through services, under the conditions of the present tariff, the articles named in article 15 of the general express tariff. The transportation of these wagons is subject to the general and special conditions of the tariffs applicable to them, except where these differ from the follo- wing arrangements. Par I. Admission of refrigerated wagons. Art. 1. Entry. Refrigerated wagons should be admitted on any one of the six large railways in France by the State Railway Administration or by the foreign railway whose stock is admitted on the French system; this entry renders the persons or concern, in whose names they are obtained, responsible to the railway administrations for the admission, running loaded or empty, maintenance, siding etc. . . . of refrigerated wagons, under the conditions set forth in this tariff. A r t. 2. Conditions of Establishment. Plans and descriptions of the vehicles should be submitted to the approval of the administration on whose system entry is desired. Applicants must ſurnish the railway with the means of seeing that this descrip- tion is adhered to, especially where the quality of the materials used in the con- struction of the wagon is concerned; the expenses of this inspection are borne by the applicants. - In case the refrigerated wagons are intended to run on several French railway lines, they must be within the minimum loading gauge of the large French systems, and they must, in every case, fulfil the conditions imposed by the Berne Convention for promoting Uniformity in Rolling Stock. Refrigerated wagons must conform to all the conditions set forth by the ordinances of the railway whose lines they are to traverse, for the admission of these 969 G. V. No. 121. vehicles on express trains, and must be provided with all the appliances necessary for them to run in these trains (continuous brakes, hand brakes, heating pipe, electrical communication etc.) For wagons furnished with a hand screw brake, the applying apparatus must be in a box accessible from both sides of the line, and in which the brakesman may either stand or sit. The axles, , wheels, oil boxes, couplings, springs, brakes etc. must have all the guarantees of safety exacted by the railway for its latest rolling stock. The railway reserves the right to refuse, or to have replaced at any time, such wagons as do not possess sufficient guarantees of safety. A refrigerated, wagon must carry inscriptions, on each side, indicating the name of the person or concern who has obtained its entry, the name of the railway which has admitted it, and the name of the station to which it belongs, the tare, the maxi- mum load, its number, and if necesary the kind of transportation for which it is specially intended. Refrigerated wagons whose tare exceeds 12.5000 kilogrammes are subject to an extra rate as stated in article 11 of this tariff. A r t.3. Reception. Refrigerated wagons are only to be entered and allowed to run after their acceptance by the contracting administration on whose lines they are to be entered. * * In case of dispute the railway has the right of refusal. The persons or concerns, who seek to enter their vehicles, must inform this ad- ministration of all the French and foreign systems on which they wish the wagon to be admitted and allowed to run; this administration, after an examination of the wagon | and the appliances with which it is furnished, must inform those concerned as to which, among the railways indicated, the vehicle may be allowed to run, and the following is inscribed on the vehicle in conspicuous letters: , Admitted to run upon the following railway systems. . . ." In case of an alteration in the conditions required for the admission of express vehicles upon the railways stated, the persons or concerns which are entering their vehicles, must carry out, at their own expense the alterations or additions which are required by the railway on which they are to be entered. In case the person or persons interested refuse to undertake this work, the inscription mentioning the railways upon which the wagon is allowed to run, shall be changed by the said railway. Par 2. Running and maintenance of refrigerated wagons. § t A r t. 4. Running: Refrigerated wagons must be sent to the railway completely | ready to run, and with their oil boxes filled. The consigner and the consignee must inform the agents at the stations of depar- ture and arrival, as to the state in which the refrigerated wagons were received and despatched by the railway, and unless it is stated to the contrary, they must abide by the decision of these agents. The railway agents have the right to refuse to allow refrigerated wagons to run which do not appear entirely safe. 970 G. V. No. 121. The refrigerated wagons are inspected en route by the agents as is the railway's own rolling stock. Additional oiling while on the journey is done by the railway. * A r t. 5. Maintenance. The maintenance of refrigerated wagons is left to the persons or concerns who have entered them, these must keep them in a good condition. The oil boxes are subject to a periodical inspection by the railway on which the vehi- cles are entered, as is the practice with their own wagons, at the expense of the per- sons or concerns who have entered them. & The maintenance of the parts ensuring safety, such as the wheel flanges, the buffer, suspension, and traction springs, the oil boxes, the framework, steps, guard plates, buffers, couplings, brakes etc. . . is to be attended to exclusively by the railway which has admitted the vehicle, and under the same conditions and times as in the case of their own rolling stock. If, while on a journey the vehicles have to undergo urgent repairs, such as the replacement of guard plates, axle boxes, buffers etc. (repairs which are usually carried out when necessary by railways upon the rolling stock of other railways), these repairs shall be carried out by the railway on which the damage has occured. The work of maintenance is carried out at the expense of the persons or concerns in whose names the vehicles were entered, and they are charged according to the net cost (general in- clusive cost.), plus the cost of extra transportation from the place at which the damage occurs to the repair shop, and hence to the station where the vehicles are put back 1 In Serv 1C e. For those parts of refrigerated wagons which are not similar to those of the wagons of the railway which has admitted them, the persons in whose names they have been entered are expected to have a certain number of spare parts ready to be put at the disposal of the Railway; this should always be the case with axles, even when the axles of the vehicles belonging to the persons concerned, correspond to one of the types fitted to the vehicles belonging to the railway which has admitted them. The carriage of these parts is charged for at the ordinary commercial rate. * If it is necessary to transfer the goods, the cost of this operation is added to the cost of transportation. The persons or concerns wich have entered wagons, cannot change in any way any inscriptions whatever, and when a wagon has been stopped running, the admission mark cannot be replaced by an agent of the railway which has admitted this vehicle, instructed to this effect. No change of any kind whatsoever may be made in the wagons admitted, with- out written permission from the aministration which has admitted the vehicle. Art. 6. Stopping or transportation necessary for repairs. There is no compensation due from the railway for the stoppage of refrigerated wagons for repairs, effected with all possible despatch. Empty refrigerated wagons sent to the workshops of the railway, either for repairs or to undergo the periodical visits of inspection to which the railway submits its own wagons, are transported on slow trains and charged on the outward and return journeys according to the following table. * mºmºmºmºmº-mº-º-º-mº ſº 971 - * - G. V. No. 121. S-me-mm-mm- | For distance up to 200 km. . . . . . . . . . 0-10 francs per km. per wagon 3) T 57 from 200 to 300 km. . . . . . . . 0-06 , 33 n 77 3) $7 57 a 300 m, 400 , . . . . . . 0°05 m jº º ży º, above 400 km. sº tº ºr a s gº tº ſº 0°02 y) 37 33 ºn r; jj 33 without subtraction of the allowance as in article 12, to the persons or companies in whose names they are entered. This charge is not made, however, when the repairs are made necessary by damage for which the railway is responsible. * - i This transportation is subject to the general conditions set forth in the slow service tariff. Par 3. Handling and transportation. A r t. 7. Handling. The goods to be sent off are only allowed to enter the station where refrigerated wagons have been brought to the place assigned for loading them. The loading and unloading of refrigerated wagons are carried out by the consigners and consignees on station platforms specially designated by the station- masters. In consequence of this a reduction of 0-30 francs per ton for each operation of loading and unloading, is made from the charge for transportation, which includes all extras. Each of the operations of loading and unloading must be carried out within a time of 6 hours. This time, for loading is reckoned from the time when the consigner is advised that the wagon has been placed at his disposal in the departure station; for unloading it is reckoned from the time the consignee is advised of the arrival of the wagon. This advice may be given by telegraph, telephone, a telephonic or express message, the average charge for this being 0 francs 15 centimes. In case of advice by telephone, the communications made by the company are stated in an entry in a special register kept by them. This register gives the name of the subscriber called up and that of the person answering this call, as well as the day, time and the subject of communication. It is marked and initialled by the administrative superintendent of the railway and checked. If the consigner or consignee or their representative is present at the arrival of the empty or loaded wagon on the train to which it is attached, or if they have ex- pressed in writing once for all their wish not to be advised, the advice is not given, and the time is counted from the time the wagon is placed at their disposal at the place for loading or unloading as the case may be. A r t. 8. Despatch. The transportation of loadcd refrigerated wagons is only undertaken to a single consignee, and to a single destination. A r t. 9. Sealing. Consigners must always lock, seal or padlock the outside doors of refrigerated wagons, and the trap doors or openings which give access to the : inside. If there are any boxes on the outside of the wagon, they must be closed, sealed * or padlocked in the same way. A r t. 10. Charges made for empty refrigerated wagons. Empty refrigerated wagons, returning empty or going to be loaded, are transported: smºsºm-ºsmº- - ºf ºn *. 972 G. V. Nr. 121. "---------------------------º-º-º-º-º-º-º-º-º-º-º: 1. By express at the rates in the following table: For distances up to 200 km. . . . . . . . 0°20 francs per km. per wagon }) 3: from 200 km. to 300 km. . . . . . 0°12 , 1) ºn 3) in . }} (K , 300 m n 400 , . . . . . 0-10 ?? 7, 5) 7) }} }; (K above 400 km. e e o o & is g º tº 0'04 7) $) }} m 75 2. By slow train, free charge being made for registration and the receipt stamp. Refrigerated wagons sent by slow trains from the factory at which they are constructed to be placed where they are to be entered, are charged for transportation at the ordinary slow train rates. The prices in the above table, reduced by 50% (without making the allowance as in article 12) reapplied to them, on production: | 1. Of a receipt relating to the transportation (receipt to the consignee or con- signer, according as it has been sent carriage pail or postage forward). 2. A paper from the railway which has admitted the wagon, stating that it has admitted the wagon. - The application for this reduction should be made within a time of four months at the most from the day of entry of the wagon. Empty refrigerated wagons sent by slow trains are subject to the general con- ditions as set forth in the special tariff for slow traffic. r A r t. 11. Charges made for loaded refrigerated wagons. Foodstuffs carried by refrigerated wagons are charged according to the rates of the express or fast ser- vices as well as the slow traffic rates, according to which of these the wagon is to run On. The charge is based upon the weight of the goods with a minimum of 4000 kilogrammes for each refrigerated wagon*) with the exceptions stated in the rates for transportation in refrigerated wagons. For refrigerated wagons whose weight when empty exceeds the maximum fixed by article 2, the excess weight is charged for at 0 francs 10 centimes per ton for each kilometre, in addition to the charge made for the goods. A r t. 11 a. Carriage of ice and apparatus for maintaining a constant temperature and of material for storing the goods. The ice contained in the ice boxes, the refrigerators, the boilers and other heating appliances, as well as all the mäterial excepting the packing, used to assure the good preservation of foodstuffs, are carried free in the wagons on the outward and return journeys, provided that the consignee does not remove any ice or appliances or any removeable material. A r t. 12. Allowance. An allowance of 0 francs 2 centimes per kilometre for each wagon is made from the charge for transportation (for wagons provided by con- signers or consignees, or for wagons let on hire by one of the French railways and then filled up), for a distance corresponding to that for which the charge is made fo loaded or empty wagons, returning or going to be loaded. *) This minimum is lowered - to 3000 kilogrammes for the carriage of butter. a 2000 7) Yº Yº 33 , fresh shell fish (crabs, crustaceans, prawns, crayfish and lobsters) oysters and fish. ' ' ' These arrangements are temporary. They expire on July 10th 1910, unless an extension is announced to the public. ... * 973 G. V. No. 121. This allowance goes to the consigners or consignees who have entered the refrigerated wagons in their own names, and who are responsible to the railways for the admission, running, upkeep, transportation, loaded or empty, siding etc. under the terms set forth in this tariff; it goes to the companies letting refrigerated wagons who take the place of consigners and consignees in fitting up the wagons, and who have entered the refrigerated wagons in their own names under the same conditions as the consigners and consignees. This allowance is not made however: 1. in the case of empty wagons trans- ported free, 2. in the case of wagons entered on foreign railways. Art. 13. Stopping. When the time fixed by article 7 of this tariff for loading and unloading wagons is exceeded the following charges are made for stopping by the railways: 5 francs per wagon for each of the first 3 periods of 24 hours 6 , , , , , period of 24 hours after the first 3. Par 4. Siding of empty wagons, A r t. 14. Charges for standing wagons. When empty refrigerated wagons are standing in a station the persons or concerns in whose names they are entered become chargeable at a rate of 25 centimes per day for each wagon. The railway has the right to send these refrigerated wagons to a neighbouring station which is convenient to them as a standing place. Their transportation to this station is not charged for, and no allowance is made. CHAPTER II. STATE, MIDI, ORLEANS and PARIS-LY ONS-MEDITERRANEAN RAILWAYS. Fresh Shell Fish, Crustaceans (Crabs, Prawns, Crayfish and Lobsters), Oysters and fish. Carried in the refrigerated wagons furnished by the consigners or consignees, or in | wagons let on hire by the raiſways and then fitted up. A r t. 1. The carriage of fresh shell fish, Crustaceans (Crabs, Prawns, Crayfish and Lobsters), Oysters and fish in refrigerated wagons, the running and upkeep of the refrigerated wagons carrying the said goods, as well as the siding of empty refrigerated wagons, are subject to the general conditions of Chapter I of this tarif, except where | they differ in the following special conditions: The despatch of goods is charged according to the general or special express tariffs by weight, the minimum being 3000 kilogrammes%) for each refrigerated wagon. To the principal consignment the owner of the wagon can add other consignments, alter loading, at intermediate stations, whether these intermediate stations are destinations or junctions of branch lines leading to the destinations. 974 G. V. Nr. 121. A r t. 2. Special rules for several consignments. The principal consignment and additional consignments are made by a single consigner. A rebate of 0:02 francs per kilometre, if it is due, is allowed to the consigner who sends the first con- signment, or the consignee to whom this is sent, on productiou of the consignment note of the vehicle. * Additional consignments can only be accepted, if the stations where they are to be unloaded are among those where the train to which the wagon is attached is carrying foodstuffs. The charges for handling are collected by the railway which does the loading and unloading at the departure and arrival stations and intermediate stations, in the presence of the consigner or his representative, if this is thought necessary. The consigner, or his representatives are expected to open and close the doors of the refrigerated wagons on arrival, or departure, or at intermediate stations. In their absence, their place is taken by agents of the railway. The consigner is not obliged to seal, or padlock the wagons. --- If the weight of the Wagon when empty exceeds 12.500 kilogrammes, the charge for the excess of dead weight, as fixed in Chapter 1 of this tariff, is added to the charge for the principal consignment. When a refrigerated wagon is to be used under the conditions mentioned in this chapter, the owner of the wagon must give advice 6 hours before the departure of the train to which it is to be attached; this wagon is to be sent to the station, and charges are made as in article 13 of Chapter 1 of this tariff, if, for any reason other than the fault of the railway, it cannot be sent off by the train intended. When the wagon is unloaded at its destination, it is to be sent to sidings, unless the owner requires it to be in waiting or to be sent to another station to be used for another consignment. *) This minimum is lowered to 2000 kilogrammes for transportations over the State and Midi Railway systems only. It is also lowered to 2000 kilogrammes, but only temporarily, for transportation over the State, Midi, Orleans and P. L. M. systems. This last arrangement ceases to be applicable on Jume 15th 1910 unless an extension of the period is announced to the public. | 975 Refrigeration by Means of Ice without Machinery. By Mr. P. Fleury, Marseille. Our paper on a method of obtaining reliable refrigeration by means of ice without machinery, was received with interest at the first congress, by those members who sought the most simple, and hence the most practical solution of this problem. R A year afterwards we sent a car to Lyons on the occasion of the k congress there, which was fitted up according to this system, and loaded with produce, the most perishable being purposely chosen. J We would inform those members who inquired as to the temperature attained, that temperature was not the most important consideration, but that the recording thermometers indicated 3° to 5° C. We would like to refute the common fallacy which assigns the most important part in this method of preservation to cold, while our object has been to keep the preserving medium dry, in contact with ice only. - Experience in preservation undoubtedly shows that this is the prac- tical solution. Moreover practice agrees perfectly with the latest data given by Science. We should cite a work of authority on this matter: * General Physio- logy, by Mr. Max Verworn, a German professor at the University of Jena. Studying the part played by water in the functions of life, and basing his work upon famous contemporary investigators, the author arrives at this conclusion: namely, that germs cannot develop in the absence of water, and that water is absolutely necessary to the existence of life. But studying the part played by the temperature, he points out that learned men, like Lueger, Raoul Pictet etc: have been able to steadily extend the limits both of very low and very high temperatures beyond which living matter ceases to thrive. They merely conclude that certain points in the scale of temperature are most favourable to the development of germs. But life exists in some intensity in the presence of moisture at tempe- ratures in the neighbourhood of the freezing point. 976 Moreover experience shews that mould, and certain kinds of gelatinous organisms, develop rapidly in the presence of moisture at this temperature. Therefore it is easy to give a reply to the question: How should ice be arranged so as to effect preservation? It should be arranged in such a way as to keep the preserving medium in a dry state. What is a medium in a dry state It is a medium in which the hygrometer indicates a state under the saturation point, in any portion of the medium. That is to say, a medium in which the vapours emitted by the products are instantly absorbed. It is a medium which is a perfect evaporator of moisture. The question being put thus, we can only think of one arrangement which satisfies the necessary conditions theoretically and practically. We have photographed the car and obtained hygrometric records of it. The ice reservoir, or refrigerator, should not only be vertical, but it should be placed in the centre for various reasons, among others not to hinder the warming action from outside. This warming action is in fact what keeps the pointer of the hygrometer in the desired position, and causing as it does interior evaporation, it gives rise to an important distri- bution of cold. -- For instance, we have observed, in the case of a load of 105 sheep carcases, a loss of 300 grammes of water per sheep by evaporation, which means a total of 31.5 kilogrammes of water. We know that the evaporation of 1 kilogramm of water produces as much cold as the melting of about 7 kilogrammes of ice. Hence the extra cold produced by evaporation is equivalent to that which would be produced by the fusion of 220.5 kilo- grammes of ice. We have noticed the small amount of ice melting which takes place, and which is explained by the additional cold produced by the evaporation from the meat. The heating action from outside, which, in spite of the insulation and complete closing of the wagon keeps the temperature a little above 0° C., has another and equally necessary effect, which is to cause the air in the chamber to undergo continual washing. Indeed this is no other than the phénomenon which cleanses atmo- spheric air of all its inpurities, and, in spite of constant pollution by the earth, air is constantly brought back to its normal and pure condition by the phenomena of rain and dew. This is the theoretical explanation of the absence of all odors inside a closed car, which has for several days contained perishable produce giving off odors. - * * The law of this kind of preservation is that the articles should be con- stantly cleansed in pure dry air, by slow currents rising over them, so that whenever they are approaching a state of Saturation a slight rise of tempera- ture raises the dew point, which would otherwise already have been reached. 977 The articles may be wrapped up and packed to a certain extent; air is a subtle substance, and penetrating like water, can reach everywhere as long as the wrappings are not air-tight. The drying effect from the point of view of loss in weight is not so important as it might seem. It is the real function of the low temperature to reduce this loss to a minimum. 4. In the second place, products are naturally formed in such a way, as to keep their natural water. Under the action of drying the surface be- comes less permeable. Certain fruits are curiously formed for this retention of their natural water, and their skin becomes so hardened, that even a hot dry atmosphere leaves their pulp moist for several months. Loss in weight is, especially no- ticeable during the early part of their preservation. It is not proportional to the surface exposed. The effect of dry preservation is favourable for different groups of perishable products. - Meat. The protection of meat against contamination immediately after slaughter, cannot be too strongly recommended. The life of germs which have already been evolved during this very favourable period, depends on the natural water inside the meat. Cold can only make the action slower and control it. It only causes a retardation of the process of decomposition. When meat is well prepared it can be hung up in cars and travel over long distances; a few days of this kind of short preservation without freezing brings meat into the best conditions for consumption. Fruit. A dry cold atmosphere hardens the skin and retards evaporation. The fruit becomes firmer and keeps longer for transport. Flowers. A temperature which does not exceed 6° C in a dry atmosphere and a method of packing which allows of the air slowly filtering through are the conditions demanded by experts. Flowers seem to keep as long as their stems are not deprived of water. The rising of the sap and slow evaporation by the leaves seems necessary to keep them alive. Arrested evaporation causes the leaves to wither and decay. Cold and slightly close packing by experienced men retard this evaporation and thus prolongs their life. Roses, cut flowers etc. have been kept as long as 18 days. Six or eight days preservation is enough for their transport; this is the opinion of the Paris commissioners. 62 978 Butter. Butter merchants have assured us that a. dry cold atmosphere is desir- able for the preservation of all its qualities. * Previous cooling of products appears to us to involve waste of time and tedious and useless processes. Heat entering products causes more rapid absorption of traces of moisture from outside, and favors the development of germs on the surface. We are convinced that it would be practical to revise the details in connection with each product, and that good implements would give ex- cellent results in experienced hands. Supple men tary note. The theory which we presented at the last meeting does not disagree with previous theories on refrigeration. The two systems are based on preservation in a dry atmosphere. Under the ordinary system which only involves previous refrigeration the products are still at a comparatively high temperature and large quantities of vapour are given off which condense on cooling. Previous refrigeration has the effect of previously absorbing the vapours by energetic ventilation. Products thus cooled only emit small amounts of vapour, which may either be absorbed by the wrappings (wood fibre, cotton, etc.) which are absorbent materials, or be held in suspension by the slight rise in temperature after the initial refrigeration. A system which establishes a dry condition at first and maintains it does not necessitate previous refrigeration. Instead of the vapours being previously absorbed, as in the one case, in the other case they are absorbed as fast as they are produced, as the products travel and are kept cold. In our system, the initial high temperature of the products gives rise to a more energetic circulation and by lowering the hygrometric state produces a draining of the vapours which is the more active as the tempe- rature is higher and the emission of vapour greater. Preservation is perfectly attained in the two systems, by the absorption of the vapours which are continually given off by the products. 9 79 Railway Refrigeration Cars. By Lauritz Nilsson, Christiania, Sweden. What are the requirements of a good refrigeration car? * A railway car is a very transient object. One day it is among the mountains of the north, with its cold climate, the next day on the hot plains of southern Sweden; one hour in the glow of the mid-day sun, an other in the cool of the night. It has to carry very different kinds of goods which require various temperatures and degrees of humidity. It is therefore not possible to satisfy, in it, all the demands for fixed, well insulated refrigerating rooms, that are comparatively indifferent to outside temperature changes, and which can be usually constructed each for a particular variety of goods. The space at disposal in a car is very limited and costly, and too complicated or bulky apparatuses cannot be employed. The weight is also of great importance, and as opportunity for examination en route is rather Scarce, this must be taken into consideration if a satisfactory result is to be attained. Starting from this point of view, we can assemble all these require- ments as follows: 1. A d a pt a bility for r a di ca 1 a n d e f fect i v e refriger a ti on. Whatever the outside temperature may be, approximately that tenn- perature must be maintained within the car which is most suitable for the various kinds of goods it contains. In Sweden the temperature seldom exceeds +25° C., and then only for a few hours at mid-day. In general, therefore a low outside maximum temperature may be assumed. The temperatures that best suit various goods differ very greatly. They are, moreover, not so well defined but that differences of opinion arise among experts. According to the claims of some very eminent experts of our own and several other countries the temperatures for the goods most generally transported are as follows in degrees C. 62% 98O Meat . . . . . . . —H 3 to + 5° Cheese . . . . . . -- 4 to +12" Fish . . . . . . . — 3 > O0 Fruit . . . . . . . — 1 x + 2* Butter . . . . . . . 0 x + 5° Eggs . . . . . . . — 1 » -- 1" Milk . . . . . . . . 0 x + 2* Beer . . . . . . —H 4 » -H 69 It must therefore be possible to maintain a temperature of at least 0°C. within the car, in order that it may be suitable for various kinds of trans- port. We can therefore determine that for our conditions it is a satisfactory cooling effect if, even at 25" outside temperature, the car temperature can be brought to 0° C. The requirements of the Royal Railways management, 0° at +20% C., are therefore not extreme, and it is not advisable to deviate from them, especially when we consider the large quantities of fresh fish, both from the west coast and from Norway, that our railways transport at present and will have to transport in the future in still larger quantities. 2. The re friger a ti on of the car must a d m i t of be in g r e g u1 a t e d. As mentioned, different goods require different temperatures. The out- side temperature, too, may vary between very broad limits during a journey. It is not at all unusual that the temperature having risen during the day above 250 falls during the night to + 10° C., or that the car that was subjected in the northern districts to a temperature below the freezing point is subjected further south to a temperature of +20%. It is therefore not enough to fix the refrigerating effect before the commencement of the journey by the use of more or less salt, but it must be possible to regulate the temperature during the journey; disastrous consequences may follow, if the temperature within the car falls too low. 3. The car must be cold a n d dry. The latter within certain limits. The kind of goods most sensitive to moisture is meat, which becomes soft in a room with too moist air. On the other hand it becomes hard and dry on the outside, and loses weight if it hangs in a room whose air is too dry. The relative moisture content that is most suitable for meat is between 70 and 75°/o; through tests conducted during recent years it has been ascertained that if properly chilled the moisture content may rise to, but must not exceed 85%. Fish on the other hand require a fairly moist air; other goods are relatively indifferent, so long as the air is not impure or stagnant. It is therefore very difficult to determine the limits for the degree of humidity permissible in a refrigerator car employed for various purposes; practically speaking it may be put at between 70 and 80, sometimes at 85%. The requirement of the Royal Railways management that meat that has not been previously refrigerated must be transported without deterioration seems to be very fortunately made. 981 s These are the chief demands made on the effect of the car. To these must be added purely practical conditions, for example that the minimum amount of refrigeration should be required, hence the insulation of the car is of the greatest importance; that the charging with ice may be accomplished as speedily as possible and that the dead weight may not be too great; that the loading space be not too limited, that the manipulation be as simple, as possible, that safety of working be ensured and that the cost of construction be not too high comparatively. Fundamental principle of the cooling of the car. The cooling of a room consists in combatting by artificial means the increase of warmth that unavoidably arises in a space in which it is desired to maintain a temperature lower than that of the surroundings. One must then first find out how great is the transmission of heat. These losses of heat arise in three ways, just as in ordinary refrigerating rooms: 1. By heat conduction by the walls, floor and ceiling; 2. by introduction of air; 3. by warm goods. To these must be added those arising from radiation, workmen, light, etc., but these are comparatively insignificant. Against the loss through radiation it is usual to make use of the protection of coating the car with a bright colour. -* The losses through conduction which are the greatest and most im– portant for the refrigerator car cannot be entirely avoided. It is necessary, however, to reduce them as much as possible by means of suitable insulation, if cooling is to be at all practicable. Particularly in refrigerator cars where the transmission of heat is considerably increased by the rapid movement of the car and the friction of the air caused therely, and where the dead weight may not be further increased by the excessive thickness and weight of insulation, special consideration must be given the insulation. It seems that in this respect an unhappy choice has been made in the cars that the Royal Railways management has placed at our disposal. The walls consist of 20 mm. thickness of boards, 20 mm. of hair-felt, 15 mm. boards, 20 mm. air space and 15 mm. boards, or a total of 90 mm. Besides this the floors receive a combination layer of wood-material and the roofs a woven covering and wooden Strips. Hair-felt is a very good insulating material but much too thin, and the air layer is of no particular value. The ice consumption for a car having 91 mº outside surface was about 25 kg. for every degree of difference between the outer and inner temperatures; somewhat less for freight trains, and somewhat more in express trains. This corresponds to a coefficient of heat transmission of somewhat above 2, which represents at least double that necessary for refrigerator cars. Whatever insulating material is made use of, it must not 982 be of less thickness than 12 to 15 cm., and for walls and ceiling cork dust or well dried sawdust, most carefully protected against moisture by perfectly airtight insulating strawboard and under this also sheet metal, for the floors 10–12 cm. of impregnated cork in two layers are recommended. Partition walls are not necessary. Such an insulation carefully executed gives during rest a thermal coefficient of '4; for the increased transmission of heat through movement and for unforeseen imperfections in the insulation it must be calculated at double the size. This would give an ice consump- tion for this car of 1 kg. instead of 2.5 kg. for each degree of temperature variation, or a saving of at least one half. It is surely not necessary to emphasize the fact that the loss of heat and the consequent ice consumption are in direct proportion to the temperature in the car, so that if the latter stands at + 1° 1 kg., at +10° 10 kg., at +20° 20 kg. etc. are necessary. Losses in cooling new air arise in the refrigerator car only through leakage and the opening of the doors. For many reasons a direct supply of air to the refrigerator car must not take place. It is of course impossible to accurately estimate these losses because one does not know the quantity of fresh air admitted. If care is taken, however, that doors and openings fit tightly and that the cracks are covered with felt or still better with rubber, and that the doors be not too frequently opened, these losses will not be very great. Warm air brings in moisture, which must be removed that it may not be deposited on the goods. Losses for cooling the goods should not occur, as the shipper should properly precool his goods before dispatching them, and the railway is required only to deliver the goods in the same condition in which they were received. The conditions, however, are such that a proper cooling before despatch seldom takes place, and the sender naturally finds it easier and more to his advantage to leave this cooling to the railway and to blame the latter afterward if they have not performed this properly. This is, however, of the greatest interest for the consumption of refrigerant and the working expenses, as also for construction, for if the cooling effect of the car is satisfactory, the goods are cooled if the transport lasts but long enough; this has great influence upon the consumption of refrigerant. If for example a car load of meat is loaded in Malmö at + 12° C. and on the way to Stockholm cooled to + 4° C., it has been necessary to use 840 kg. of ice, whilst for the car if it is well insulated probably only about 400 kg. would have had to be employed, in order to maintain the temperature. The replacement of the thermal loss is effected by melting ice, the effect being transmitted to the air in the car. This transmission is caused either by direct contact of the air with the ice or with the cold surface of metal, itself cooled by direct contact with the ice or with a liquid cooled by the immersion of ice, or, finally, as in the Frigator system by cooling a liquid as low as possible in a special apparatus and then pumping it through a metal refrigerating system that is suitably located for cooling the air in the car. f - 983 The first way (cooling the air by direct contact with the ice) is very much employed and is carried out in various ways. The best way is to pass the air over a bulk head from the roof downwards, a fairly long route, through broken up ice. It is thus always cooled and the moisture is taken up by the ice, owing to the cooling. This method of cooling, however, is very imperfect, and it is impossible to avoid its defects. The ice does not melt below 0° C., and therefore there exists no special difference in tem- perature between the air and the ice. The ice also absorbs its heat of fusion very slowly. For this reason very low temperatures cannot be attained. The drying effect is also deficient. When the air leaves the ice it is saturated with vapour which has proved harmful. The air becomes raw and humid and quickly injures sensitive goods, with which it comes into contact. It causes mould and other bacterial growths the effects of which have been frequently observed. This cooling system can therefore only be used to advan- tage when less sensitive goods which do not require so low a temperature are to be transported e. g. beer, cheese, milk, etc. The cooling by refrigerated metal surfaces has the advantage that the drying process is considerably more effective because a strong contest against the vapour in the air can be maintained. Undesirable emanations such as arise from ice do not occur. The heat transmission is much more effec- tive, and if it is possible to provide sufficient surface and to keep such as is provided sufficiently cold a very good cooling of the car is possible. To attain the best effect with this system it is of importance to maintain the greatest possible difference of temperature between the air in the car and the refrigerating surfaces. This is partly achieved by locating the cooling Surfaces in the warmest part of the car and partly by cooling the surfaces to the utmost. If ice alone is used for this purpose it is im- possible to get a temperature below its melting point or 0° C. For this reason the melting point is lowered by the addition of salt, a lower tem- perature being thereby insured. The temperature of a salt solution sinks about *ſ,"/, for each 1% of salt contained in the solution, down to -18°C. The temperature of a solution containing 10"/o of salt is, for example, —74° C., one with 20°/o — 14:49 etc. The more salt added, the lower the temperature and the better the effect attained. The maximum cooling effect is attained with 25°/o of salt. It is also necessary to maintain the upper surface as nearly as possible at the temperature of the solution. By the direct contact of the ice with the metal, which takes place if one places tanks filled with ice and salt in the car and if the thaw water is periodi- cally drawn off, this cooling becomes very imperfect, the ice touches the surface only in places, the more chopped the better, and when the ice melts a large portion of the refrigerating system is out of service. A more thorough and more even cooling takes place when the cisterns are filled with water or freezing mixture into which the ice is placed. In such cases the whole upper surface is in contact with the cold liquid independently of { 984 the presence of more or less ice, and if it be but possible to keep the liquid at its freezing point, the best possible result is attained. Experience, however, has shown that such is not the case by a long way. The powerful transmission of heat through the metal walls, the slowness of the ice in absorbing its heat of fusion, which being augmented by the lack of circu- lation of the solution, causes the temperature at the metal wall to remain several degrees higher than the temperature of the solution. It would be somewhat better if conducts were connected with the tanks which should assist the circulation of the solution. To this must be added that the tanks become heavy and ill formed and also cannot be placed where might be best; that the cooling effect is decreased by the dilution of the solution through the melting ice, that with them it is not possible to obtain such an upper surface as is necessary for effective cooling, and that, even if a sufficient effect could be attained, it would be impossible to regulate it When the cars have once received their charge of ice and salt they cool irrespective of changes in the outside temperature, and irrespective of whether cooling is needed or not. For this reason serious complaints have been made in countries where these cars are most used, namely, in America, although they are far superior to direct cooling. The refrigerating arran- gement is generally placed behind a wall whereby the air through its own increase of weight in being cooled is forced to pass from top to bottom. Hereby there arises a fairly considerable difference of temperature, often as much as 89, between floor and roof, which is not particularly favourable. The transmission of heat itself from the air is to an important degree, increased, or diminished with the velocity at which it passes the cooling surface. The well known formula for this is 2 × 10 Wv, that is the transmission of heat rises almost with the square root of the velocity of the air in metre-seconds. The greater the difference of temperature between air and the cooling surface, the more active is the circulation and the greater the cooling of the air; it stops almost entirely if the difference has sunk to a few degrees. * -- - As it was impossible to obtain suitably placed cooling surfaces in this manner it was tried to increase the effect by - fans driven from the axles of the trucks. The air was thus forced round the room, in order to increase the transmission of heat to the tanks; no practical result however was achieved. The speed of the cars is very irregular, and the maximum speed of the air must not exceed 4 metre-seconds, whereby the effect is only doubled, if all air passages around the tanks are well proportioned. The slower the car travels, the less will be the effect until it ceases when the car stops. The mechanism is easily disarranged and is also difficult to regu- late; it has been condemned for this reason. Almost everywhere where trials have been made with it. - This summer a car was tested with 8 dry tanks, but with the change that the thaw-water was not allowed to flow off, but was stored to be used 985 on recharging. It seems that the transmission of heat was so insignificant that it only amounted to 6 units of heat per hour per sq. m. and degree difference of temperature of the air and the solution, when this difference was 22:50 and the velocity of the air the greatest possible. As previously mentioned this results from the fact that a great part of the refrigerating surface remains uncooled through the shrinkage of the ice, and the refri- gerating surface itself is never cooled to the temperature of the solution. Knowing these particulars it is easy to understand wherein lies the superiority of the Frigators system. Just as in the brine tank system the refrigerating surface is cooled by a solution, which itself is cooled by a specially constructed apparatus as near to freezing point as possible, at least to one degree above it. Thus cooled the brine is led to the refrigerating zas aewºche oes Wagens /4 ſoa : A C///Z/42767//y/y/7///ZA/7/77/67/77OAP.5. V57A/7. Aoo'ee: /9}oo. • . Afs/aduazº (26 Zoo. . - //A 55-57A 6 /:20 Zºsverðrºzcº //gar.5/vade ſºr/eden grad Vemaera/orseokanz Zer/evcº &Aerºsze/a/ aerzo& 70% - - 2/ezrösse Zemoerz/orseokoog 0°ée’.35/?osseo/en/2c/a/. ,-- The new 2Prigators Car, as it runs on the Swedish state railways, and its practical results. System by a pump arrangement which is driven by the car axle, and from here it returns again to be re-cooled. - As the refrigerating system is separate from the ice contained it can be placed in the most suitable location in the car and can be made in any form, size and construction best suited for the purpose. Through the velo- city with which the solution flows through the refrigerating system the - transmission of heat is considerably augmented, and no superfluous liquid to add to the weight of the car is used. - The refrigeration is regulated at any time by stopping or starting the pump by hand or by means of an automatic arrangement. The cooling surfaces in the 2Frigators car consist of 2" refrigerating pipes which are hung along the middle of the ceiling of the car. The air 986 is warmest here and when cooled gradually sinks, through which operation the temperature in various parts of the car is kept very even. To assist the drying of the air the pipes are arranged zig-zag in several rows, so that the air, every time it passes the cooling surfaces, must come in contact with several pipes, and its moisture must thereby be thoroughly extracted. In order further to direct the air currents the pipe system has a slanting drip floor on each side; these are highest at the sides of the car and form guides for the air, catching the air on each side of the car. The air circu- lation is therefore a natural one; the air which rises through warming against the walls is led at the roof to the refrigerating pipes; it is here cooled and sinks again in the centre of the car to be afterwards distributed to the sides. In this manner the circulation necessary for the dryness and freshness of the air is distributed in the whole car. The more the pipes are clustered at the centre and below one another, the drier will the car be. Experience has shown that if there are 6 pipes one over an-other the humidity is about 60–65% ; if only 4, as in the Swedish cars, it is 65–70%, at + 2° to + 4°, in an empty car. To catch the drip from the pipes in the car a system of gutters is so hung under them that it allows the cold current of air to pass through, but catches the thaw-water. The ice container in which the brine is cooled is placed at one end of the car. After being cooled the brine is collected in a tank on the floor from which it flows through a pipe that leads to the pump en route to which it is filtered through a double filter arrangement in order that no dirt may get into the refrigerating pipes. These filter arrangements are outside the car, to be easily accessible for cleaning. The thaw-water is periodically drawn off but is previously warmed in a special system of ribbed pipes located below the ice container. The salt is not mixed with the ice, but in order . that the salt content of the solution can be controlled it is introduced at a particular location of the ice container; this is made large enough to contain sufficiently large quantities of ice. It is placed behind a bulk head, just as a refrigerating tank, and like such it forms a special value when the car is stationary on a ferry or at a station, and cooled brine is consequently not being circulated. The ice container and the solution stored in the pipe system as well as the ice accumulated thereon permit the temperature in the car to increase but inconsiderably even if it remains standing for several hours. . . 987 How does the ,Frigator“ system fulfil the above mentioned requirements of a good refrigeration car? 1. The cool in g of the car to 0° C. when the outside tempe- r a tur e i s -H 259 C. No hindrance being present to placing a sufficiently large refrigeration system of powerful effect in the car, it is clear that with this construction a good effect can be attained. It is only necessary to explain the conditions under which this result is to be reached; i. e. at what salt content of the solution and temperature thereby produced it is desired that it be attained. It was seen that the coefficient of heat transmission of this system was about 12 at 8 to 12° C. difference in temperature between the temperature in the car and that of the brine, figured for the same difference. If one thus knows the heat absorption for each degree difference of temperature, it is very easy to calculate how large a refrigerating system must be in- troduced in order that at a brine temperature of for instance — 10° C., Corresponding to a 14% salt solution at an outside temperature of 25° C., 0° C. may be maintained. This done we have the proportion of the cooling effect of the car = 10:25 or 1:25, i. e. with every degree of difference between the temperature of the solution and the temperature of the car one reckons 2.5 degrees difference between the temperature of the car and the outside temperature. This figure expresses the cooling effect of the car. very exactly, and, if one knows it, it is a very simple matter to cal- culate how the car will work under various conditions, and how much salt must be used to attain a certain result. It is surely not necessary to say that at such refrigerating proportion a still lower temperature at +25° C. or 0° C. at a still higher outside temperature can be maintained, by lowering the temperature of the solution through the use of a greater percentage of salt. With 20% of salt and – 14° C. brine temperature the car temperature becomes — 3° C. at +25° C. outside and keeps the car at 0° C. at +35° C. outside tem- perature. With larger refrigerating systems the difference can be increased at will. It becomes a purely practical matter for calculation to what extent it is advantageous to decrease the consumption of salt by means of a larger refrigerating system and greater cost of construction, or the reverse. It is impossible to approach these results with an ordinary ice tank system, either with or without fans and still less possible to do so with direct ice cooling. *"… 2. Regulation of the co o 1 in g. This is in the first place effected by decreasing or increasing the amount of Salt used for various seasons and kinds of goods. The further regulation which is mentioned as being necessary, is effected by stopping or starting the brine pump. This is effected by means of a ventilating ar- 988 rangement which is operated by an apparatus, sensitive to heat, which opens the ventilator when the temperature in the car has fallen to a certain point and closes it when the temperature rises above it. This apparatus can be adjusted so that it can be set in advance for the temperature required in the car. - Special attention to it is therefore not necessary. Besides this the cooling can be stopped by simply turning a handle, if this is necessary, for example if the car is moved before or after being loaded. By means of this arrangement one ensures partly a very sensitive regulation and partly that only the necessary quantity of ice is consumed. 3. D e g re e s of t e m per a tur e a n d humid it y in the car. As before mentioned the system can be so arranged that the desired degree of humidity of the car can be maintained. It is unfortunately im- possible to change this for different kinds of goods. If water is spilled on the floor so that the air can absorb it the humidity will be considerably increased if necessary. The moisture content, attained by four pipes one over the other, has proved the most advantageous. If the car is at rest the moisture content rises somewhat after the ice on the pipes has commenced to thaw. The loading of the car is accomplished in the simplest and most ex- peditious manner, because the ice is only placed in one spot, as it is of no importance that it be well chopped, and no time loss through mixing the salt occurs. If the ice can be quickly obtained, the whole charging only occupies 2 minutes. The management is the most simple imaginable. The cleaning of the filters and the ice reservoir must be effected now and again just as in the case of the ice tanks. If before departure of the car the adjustment is made for the desired temperature, it works without further attention just like any ordinary car. - The weight of the refrigerating apparatus comes to about 40 to 50 kg. per m” of cooling surface including the brine, and this is considerably less than that of the brine tank system. The useful space that it takes up is much less than in another arran- gement because the pipes are placed below the ceiling above the loading space, and the ice container is put in some corner. Even this summer it was found that the available floor surface was 1.57 m” larger and the cubic content 2 mº more in a > Frigators car than in the same car fitted with the ice tank system or direct ice cooling. As the available space directly repre- sents capital this is closely related to the price of the car. Considering the avai- lable space in the car, which is the only calculable factor, the cost of a »Frigator& car is but insignificantly higher than that of another car, and one has a car that is far superior to all others. If on the other hand the useful effect is taken as the starting point the x Frigator & car is far cheaper. 989 Practical results with refrigerating cars of the ,Frigator“ system ac- cording to official data on trial journeys, which were conducted in the summer of 1909 by the Swedish state railways. ~. * An offer to test the direct ice cooling system against the , Frigators in two old refrigeration cars of the Swedish state railways, the same to be taken over by the Royal Railways management for a definite sum if they Satisfied conditions made in advance for a good refrigeration car, was accep- ted, and the following conditions made. The cars were to be used throughout the Summer, and during this time must satisfy the following requirements: 8 - Why: Gr o, 9% ag. 7 of Zarz – Z27a Zzzz 6. Azzºzer 1. the temperature of the empty car, even at 20° C. outside tem- perature, should be able to be reduced to 0° C.; 2. Such degress of the air should be able to be attained that meat that had not been previously chilled could be transported without im– pairment. 3. important offences against the reliability of working should not OCCUIT. If these conditions could not be fulfilled the arrangement should be again replaced by the former equipment without cost to the railways. The diagrams sent of the cars showed the previously mentioned very meagre insulation, which resulted in a comparatively large refrigeration system, 31 m3, 990 being installed. As it was proved in advance that in a car delivered to the Norwegian state Railways the superimposed brine pipes gave a moisture content of between 60 and 65%, which was thought too low, only four tubes were put in. s Afterwards an offer was made by two other parties to install an im- proved American ice tank system with eight cooling tanks, four at each end of the car. This offer was also accepted, so that the Frigator, system was on several trial journeys in direct competition with the tank system. Before the cars were delivered one made a journey with butter from Tollarp to Malmö, 83 km. on the 9” May, under supervision of the dairy overseer, Engineer C. Hultmann, Malmö. The outside temperature was not 25 8 ſo } //ºr Enzené. gz: o' 79-294 29. Es/6/ – ſtockho 4772. Fleisch high, on an average + 12° C. The salt addition was 8 "lo. The car left Tollarp at 10 a. m. and arrived at Eslöf at 1 p. m., the car temperature having fallen to 0° C. During stoppage till 515 p.m. the temperature rose to +25° C. On arrival at Malmö it had again fallen to 0° C. The load, 8000 kg. butter, was cooled during this time from +8.5° C. to + 5° C. After the cars had been delivered the first trial journeys were made from Malmö, Eslöf, Stockholm, 618 km, on July 3° and 4” with a load of unchilled meat, and from Stockholm to Malmö, on the 7" and 8*, with cars empty were undertaken, being controlled by an engineer chosen by the Royal Railways management, to see how the first two conditions would be fulfilled. The cooling, tanks also took part on these journeys, and their tem- peratures are dotted on the diagram. - 991 At Eslöf somewhat over 3000 kg. meat was loaded in each car. The transport lasted from 8:30 a. m. on the 3" July until the same time on the 4*, or in all 24 hours. The meat was cooled in the "Frigator car from + 17.5° C. to + 3° C. The atmospheric temperature was on an average + 17.2° C., and 12.4% salt solution was used. The moisture content was abnormally high, averaging 84.7%, which was due to the fact that the floors of the cars were wet with water that ran out of a package of casings. From this it was seen that the moisture content of the air could increase con- siderably if opportunity were offered for absorption of moisture. The meat was in excellent condition on arrival. - With the refrigerating tanks the meat was cooled to + 11.3% after having first been cooled in an ordinary car, with open doors, to + 13 °. The salt solution was 20.4%. The moisture content was 74%. d 7-3/, og SAockhozzzz – 272.277. 6. Zeerer Wager. Trial trip s with empty cars. The trip lasted from 11 a. m. on the 6* July from Stockholm, till 10 a. m. on the 8*, on arrival at Malmö, with a stop at Elmhult of five hours. The 2Frigators car at first travelled with the apparatus not working, then with the apparatus working without salt, and then with salt added; this was increased from 10 to 15 and then to 20%. The last two hours the apparatus was again stopped. The refrigeration tank car ran the entire time with 20% salt, which corresponds to a solution of 21%. As may be seen from the diagram, the * Frigators car was entirely uninfluenced by the outside temperature; the inside could be lowered at will, whether the outside temperature rose or fell. When operating the refrigerating effect was = 1:18. With a 21% salt solution, whose temperature is — 15°, the car temperature reached 0° at + 27° outer temperature, and at +20° outer 992 temperature –3° was attained. It thus exceeded the preseribed guarantees. The moisture content averaged 67%. • - - The refrigerating tanks had only a refrigerating effect of 1:03 or ‘’s as great as the 2Frigators, although their refrigerating system was only 'la as great, and this is explainable by the previously mentioned bad trans- mission of heat of the tank system in comparison to the x Frigators. With 21% salt solution, therefore, at 20° outside temperature only + 11.99, could be attained, and to maintain 0° it would be necessary that the outside temperature. were but + 5°. The moisture content was 55.1% on an average, . therefore much too low. w + To determine the value of the insulation of the car, ice weighing tests were made during these journeys, which showed that for each degree of Wºr Aussené Zºe 7emp des Fleischs. Innenéemp (77. d 3-4/2. o9, es/ö/ – Sºock/ o 2 m. FZeisch temperature decrease, in fast moving trains 275 kg. and in slower trains 2.35 kg. of ice was used per hour. This must be considered twice as much as should be consumed. That this heat absorption should be attained in spite of such results proves absolutely the superiority of the "Frigators system. The trial journey on which these results were attained is of interest, because it shows the relative humidity in the car when loaded with meat without any abnormal outside conditions being present. It was on an average 71% for the Frigators and 62% for the refri- gerating tank system throughout the trip. - - It was proved by these trips that the 2Frigators car fulfilled the first two conditions very satisfactorily. r - Several longer trips that the "Frigators car made later on, in the autumn, are worth more exact mention. Fish requires much lower temperatures 993 than meat, that they may keep long enough to be transported from the distant fishing places to the large markets. For this reason great differences of price occur in comparatively short distances, especially for the sensitive sorts. This could be compensated for, to the advantage of fisheries and consumers, if the fish could be transported for longer distances without risk. As we have to deal with large sums here, not the least of which are for freight, and as the "Frigators cars, in competition to all other refrigeration cars, had shown themselves to be so independent of the outside temperature that they could maintain temperatures below 0° suitable for the fish, under all conditions, it was desirable to determine the practical results by means of trials. After a somewhat less interesting trial journey from Drontheim to Stockholm, at low outside temperature and with less perishable varieties of fish, had been undertaken for this purpose, another trip was undertaken from Drontheim to Germany with a load of herring and the more perishable varieties of fish, cod and haddock, according to the diagram below. The fish were packed in cases without ice. A special attendant was not sent with the load. The inner temperature was therefore recorded by a registering thermometer, and this showed not only the temperature, but also, by the thicker records (caused by the vibra- tions of the car), whether the car was moving or not. The outside tem- 63 994 ºperature was recorded by the guard, the station officers and others, and as on all other trips was taken from two thermometers, one in the sun and one in the shade. The temperature of the fish was -H 4° C. on departure and fell slowly to + 1" C. The journey began on 5* October at 835 a. m. The cod had been caught on the previous morning and the haddocks three days before. Stops during the journey were made at Ange (3°), hours), at Alfvesta (10/s hours) on the ferry Telleborg to Sassnitz, Sassnitz (6°/, hours), and at Stralsund, through an error in transscribing the record (15'ſ, hours), or 36"/, hours altogether. At Stralsund 24 more boxes of fish were loaded, which also caused a very noticeable fluctuation on the diagram, and from there the car went to Rostock, where it arrived on October 8* at 11:50 a. m. The load was judged by experts in the afternoon, and it was in such ex- cellent condition that it was determined to send the cod and haddocks to Berlin the following night by ordinary train. There it was found to be faultless and was sold at the fish auctions at full normal prices. Because of the long, unforeseen detentions, the trip required 76 hours in the refrigerating car, and with the stop at Rostock and the transport in ordinary car, in all 100 hours or about 4 days, while the fish were in no way inferior to those which came direct from the North Sea coasts. During the journey only a part of the refrigerating effect of the car, with 11.3% salt solution, was made use of To test how long the fish could be kept sound in a refrigerated room after the transport, some boxes of cod and haddocks were unloaded at Hessleholm and sent to Christiania where at 0° C. they were placed in cold storage. Some was sold daily, and not until the 215" was a reaction noticeable. The haddocks were then 19 and the cod 17 days old. It had been intended, after this trial, to go as far as Narvik, and to send fish from there to central Germany; but as such a journey could be carried out in the same time as that mentioned, the practicability of such a shipment was already established, and for this reason the undertaking was dropped. A later journey with both x Frigator & cars, from Drontheim to Stralsund and Rostock, was carried out with equally good results. In one car the temperature was (for trial) kept so low that the fish was cooled to — 29 C., without freezing. During this latter journey, contrary to that pre- viously described, the fish were laid in a little ice, which appeared to have a favourable influence upon them. The outside temperature was also lower, especially during the first part of the journey, and sank even to below freezing point. As one proceeded southward it rose during the day to + 18°C. This shows how necessary it is to be able to regulate the cooling. --- As these trials sufficiently prove that with the Frigator & car even very sensitive fish can be transported much further than with other systems, its importance for the fisch trade is perfectly apparent. The cars were reiced only once on the journey, and much ice still remained on arrival. With the new, well insulated cars it is only necessary 995 to fill with ice once, and with the same ice the journey from Drontheim to Germany can be made, if the average temperature does not rise above + 14° C., which it seldom does in late summer. The ice tank in the car holds 800 kg. of ice. * For other transports, too, the superiority of this car is proved by the trials. That meat can be cooled in 24 hours as well as in cold stores of slaughter-houses, and that in some hours butter, so difficult to cool through, can be cooled in tubs from + 8.5° C. to + 5° C., are achievements which Speak for themselves. Complaints against the certainty of operation of the car were not raised during the summer, and at the beginning of November the cars were taken over by the Royal Railways management, with the acknowledgment that they had fulfilled all conditions excellently. 996. A Method of Reducing the Difference in Tem- perature which Governs the Operating Ex- penses of Refrigeration Cars. By M. A. Kroupsky, Engineer. In those of your problems and calculations dealing with the trans- mission and exchange of heat through walls of insulating material having greater or lesser efficiency the temperature of the extreme exterior super- ficial layer (for instance the last coat of warnish covering the body of a car) is assumed to be equal to that of the surrounding medium; for a car or any installation on the ground, this is the temperature of the outside air or its average temperature for a season or a day. And it is only natural that this assumption should be made, that is to say that the temperature is equal to that of the outside air, in the calculation of interchange and equilibrium of heat where refrigerated cars are concerned, or a balance in the exchange of heat through the walls of a building. The fall in temperature, or constant average difference assumed or deduced for all the 24 hours, determines the quantity of work which must be done to maintain equilibrium at the desired value, when a fairly constant temperature is desired in the interior for a given higher outside temperature. In the preliminary calculation for a refrigerating car under the climatic conditions of the temperature zone in Europe, it has become customary to fix, as a basis for calculation, an average difference of 20° to 25°C., which is to be kept up by refrigerating operations inside the car in summer. If we had a means of reducing the actual temperature difference between the temperatures maintained inside and outside the car this would amount to a more or less considerable reduction in the amount of work to be done and of the expense of car refrigeration; or, for the same expense for refrigeration, a lower temperature in the car, or more effectual refrigeration; that is, to put it in another way, the same refrigerating effect in cars having walls of less insulating value. If we assume the temperature of the outside air for the day at 22° C., and that of the interior of the car under given conditions of insulation at 5° C., the expense for interior refrigeration is determined 997 by a temperature difference of 22 – 5 = 17° C. If by any means the temperature of the outside surface of the car body is lowered, say to 8°C., we have 22 — 8 = 14, and we deal with 14 – 5 = 9° C. temperature difference between the exterior and interior, the . expense of refrigeration would thus be reduced in the ratio 17 to 9 or about one half; and so on in the same way. The advantage of such a reduction is manifest, especially if it is ob- tainable by a simple method and without great cost. The cooling effect obtained is comparatively slight yet effective. We have quite a simple method of effecting this auxiliary cooling, in the process of the evaporation of water, which may be made especially active in the case of moving cars, due to the forced current of air. To succeed in cooling the outside surface of the walls, the external layer in the construction of the insulating walls consists of a porous covering, periodically sprinkled with water, which it retains, distributed over the whole surface of the car. In order that the temperature of this moistened layer be immediately lowered by evaporation to the dew point corresponding to the atmospheric conditions, it is absolutely necessary for this evaporation to be started by a forced current of air, a condition which is fulfilled in the case of the cars in a train, . by the motion of the train. A most remarkable fact, as well in the phenomenon itself as in the practice of this exterior cooling by sprinkling, is, that once a low temperature is obtained (which occurs with a current of air in a few minutes, from one minute upwards according to the speed of the train) it maintains itself always at the same temperature in a wet layer when the train stops, without any trouble being taken, as long as there remains some unevaporated water on the covering. The rapidity of evaporation of water at a given temperature, or the quantity evaporated per hour from one Square metre evaporating surface, increases rapidly with the force of the air current blowing over the surface. !)irect experiments have been made to determine the actual values of this corresponding to different temperatures, and rates, of the air current. For the speed of a goods train consisting of cars containing peris- hable products, say a rate of about 40 to 43 kilometres per hour which comes to 11 to 12 metres per second, the curve in the diagram shown represents the amounts of evaporation corresponding to temperatures bet- ween 18° and 71° C. To compare the corresponding rate of evaporation in a current of air travelling at 11 to 12 metres per second to that in still air, the same diagram (given below) gives the curve of evaporation accor- ding to values found by Barret-Claudel (formulae and information etc.). For instance it may be seen that at tº mperature of 40° C., evaporation by still air with natural circulation gives 1 kg. of water evaporated per hour per square metre of surface, the same evaporating surface gives about 6/, kg. per hour, under the influence of a forced air current travelling at 11 to 12 metres per Secound; the results 432 in still air, and 44 in a current. As 998 Celsius: 15 - 20- 25 - 5o- 55° 4 o° H5° 5 o° 5 5° 60° 65 * Fo° F5° 80° 85" Ordinaten-Maßstab B.) 5QKS. 10kg d »H. s. Vitesses d'évaporation. VIP S. * - sº «. § Verdampfungsgeschwindigkeit S 46,5 k k3. I 15 S. (Dieselbe Kurve im 5fachen § Ordinatenmaßstäb: Maßstab B) S "N § 0 8 V. § t § S S 55 7 S S Q- S SO S S Z Jm Luftstrom § N Y- N 25 5 N § S N § 20 t; § S § II –15 J S W) S §– o 2 „-’ D S § Jn ruhiger Luft: § bei C° 18° §T-5 1 kg. K1,22 OkZ T S T! P e r 3. t U. °C –>15“ 20 25 50 55 40 45 50 55 60 65 7o 75 80 85 90° "R. C12“ 16 20 24 28 52 36 40 44 48 52 56 60 64 68 F 2“ Fig. 1. 999 in the case of evaporation on the surface of the car walls at ordinary out- side temperatures between 18" and 40° C. the evaporation curve is traced in the same position and to a scale of quantities evaporated (upon the abscissa) which is 5 times as large (the curve shown red). Between the temperatures of 21" and 38° C. for the external air, we should have quantities of water between 1:5 and 5.5 kg evaporated on a surface of one | * : ry | | i - :l: square metre per hour. Or, if we take a total of 50 sq. m. as the exter- nal surface of a car, we get amounts of water from 75 and 275 kg. eva- porated per hour for cooling a train travelling at a rate of 40 to 43 km. per hour, which is the maximum speed for goods trains. The use of a porous covering, which lowers the outside temperature all over the car by evaporation, gives, by the proposed method, a car which is refrigerated inside and out, called a refrigerating car with outside 1000 cooling, of which we give an illustration from a paper by Prof. Kroup sky (of St. Petersburg) which has lately been received. Sketches 1–3 represent two views of a design for a refrigerator car having the upper ice containers G G furnished with side pockets for containing the reserve salt, when refrigeration is being effected by means of ice and salt (for interior temperatures below zero C). Fig. 1 is a side view of a wagon on the same side as the loading door, the part to the left being a vertical section, and the other part, with the loading door, showing as clearly as is possible on a sketch, the outside covering which is the evaporating layer. This absorbent covering is made up of substances . which retain a considerable amount of water after being sprinkled, consi– sting of the following: 1. Various materials such as water-proof felt, coarse linen, cotton or jute, sheets of cotton, wool, straw-board, etc. 2. Covering coats consisting of granulated substances which are sufficiently porous, such as granulated pumice stone held together by a thin coat cement ; asbestos materials, sponge clippings confined by well stretched coarse can- vas. It should be noticed that the evaporating covering must not be un- necessesarily thick. In the example described the covering is made in a double layer; an interior cloth being of coarse soft cotton (which absorbs more than three times its weight of water)'); an exterior covering of Sail cloth, treated with boiling water. The covering must be well stretched over the car which it covers so that it is in close contact with the wall; it is secured to the two side walls by means of thin strips of varnished wood, (depeb. penscu tringles) placed vertically at intervals, and fastened down by screws (as is shown on the loading door fig. 1). The arched roof of the car which also has an absorbent covering has above this a covering to protect it from the sun, as shown fig. 1 (z. z), . Figures 2, 2a and 2 b represent details, where the roof meets the side walls, the absorbent covering being indicated on all three by fairly thick black lines, which show a kind of stretched corrugated padding of wool or hair. It is important that sprinkling, when the covering is saturated with water should only take place periodically (at intervals as far as possible apart), and the covering must be capable of absorbing as much water as is necessary for one hour's evaporation (by a current of air). The following table gives the quantities of water required per hour for different speeds of the train, calculated for an evaporating surface of 50 square metres and for a temperature throughout the day of 25° C. | Speed of train in kilometres per hour 10 21 32 42 t” = 25° C. Water evaporated per hour from 50 | square metres in litres . . . . . . 37 86 104 134 1) To obtain the best results mats are taken interlaced with (porosscu izciscobscu) bands of lime bark (cambium) treated with a hot solution of soda until softened, after which they become very absorbent. 1001 For the wagon described two kinds of material have been used for the absorbent covering, a thick soft material made of raw cotton (prepared by washing with soap) forming the first layer — and above this sail cloth (also treated by a hot alkaline solution with soda). Most materials of the same kind as the first layer absorb an amount of water 3 times the weight of the material used, giving it off under slight pressure. Now, if we take into account the interior layer only, a piece of cotton material weighing 0-7 kg. per square metre dry, the 50 square metres stretched over the car retain on being sprinkled 35 × 3 = 105 kg. of water, an amount which, for a maximum train speed of 40 km. per hour, would be sufficient for evapo- ration from that surface for 50 minutes, and for a speed of 32 km. per hour, for one hour. Thus the necessary soaking operations are placed at sufficiently long intervals, the table indicates the periods at which Sprinkling must be repeated under these conditions. Appliances for carrying water and lifting it to the roof of the wagon are indicated in fig. 1 (the right hand side) by the numbers 1, 2, 3, 4 and 5, also by the two numbers 3, 3 on the transverse Section. The arrangement of the parts for the water supply could certainly be carried out differently; in the present case the sketches only show important details; a water tank I shown in figs 1 and 3, in the service compartment attached to the car, serves at the same time as a pressure chamber to raise the water by the pressure of the air forced in by a small air pump of the Jäger type, 2, fig. 1.) In the same figure and in fig. 3 the pipe 3, 3, 3, which carries the water up from the pressure chamber to the roof is connected by a cross to the horizontal pipe, 5, 5, 5, which lying along the centre of the roof and lifted a little above this by the brackets 6, 6, 6, forms the sprinkling pipe. It is furnished with a series of outlet orifices (about 40 number) in line, turned towards the roof. Thus the roof first receives the supply of water on its absorbent covering, and then distributes it to the right and left of the longitudinal axis on the two sides, and (when considered necessary, especially when the wagon is not provided with a service compartment) on the ends as well. The illustration also shows several details of the arran- gement of a kind of hydraulic valve affixed to the sprinkling tube to insure a uniform discharge from all the orifices over the whole length of the pipe. The amount of fall of the pipe is regulated on the upright part by a vertical piece of pipe placed on the intersection of the pipes (5a) whose upper end is a small bell shaped vessel con- taining a valve which serves to prevent excessive pressure in the pressure chamber. We pass over these parts of the description as structural details which do not concern the essential points of the proposed system. The *) The best arrangement would be to apply pressure at different times by a pipe coming from the reservoir of compressed air belonging to the braizes, a small automatic piece of mechanism actuated by clockwork opening the pressure valve or the cock allowing air to pass from the pipe to the pressure chamber. 1002 working of the pump connected to the pressure chamber takes place, whether the train is running or stopping every 40, 50 or 60 minutes, according as the speed is 30, 20 or 10 km. per hour when the train is in motion, and the quantity of water supplied to the covering at one time does not exceed the amount by which the covering is completely saturated. . The subject of the patent") is set forth as follows: • A wagon for carrying perishable products, provided with arrangements for interior refri- geration by natural ice or by refrigerating machines, and distinguished by the fact that the roof and sides are covered on the outside by a fibrous or porous covering which absorbs water, for the wetting of which pipe 5, with orifices, along the top of the roof provides water from a reservoir I by means of a pump worked by hand or driven from the wagon axle, the pressure being regulated at the end of pipe 3 by bell shaped vessel 7. The wagon as above described is covered with an awning Z as a protection against direct rays from the sun. The use in the same wagon of an air pump forcing air under pressure into the water reservoir.< It should be noted that the evaporating covering for exterior cooiing could be attached to any refrigerator car working on any system, and a propos of this, we recall the construction of the refrigerator car on the Podbereski system”) which is distinguished by the use of a metallic casing (of thin perforated zinc) inside the car placed all around the wall and fastened above to the edges of the ice tanks in such a way that the water from the melting ice runs over its surface turned towards the wall, and thus acts as a casing for conducting refrigeration, distributing a uniform temperature over the whole chamber in whatever way the goods are arranged (the arrangement of these have a considerable influence, a is well known, on the equalizing of the temperature tº over the whole space). If the interior conducting casing is combined with the exterior covering as above described, we have an interesting type of wagon having interior and exterior Cooling surfaces. *) Nr. 16402, Dec. 31. 1909. Presented june 5, same year. Prof. Kroupsky. *) Knonn in Paris ſrom the Exhibiton 1900 by his prominent participation in the Agricultural Congress, and the Conferences of the While Cross, details of which were reported in the Paris news papers at the time. *. t 1003 TRANSPORTATION OF PERISHABLE FREIGHT » IN AMERICA. Present Practice and Desiderata. By EUGENE F. McPIKE, Secretary, Railroad Refrigerator Service Association, Chicago, Ill., U. S. A. - An exhaustive report of eighty-four pages relating to the trans- portation of perishable goods in America was prepared by Mr. J. M. Culp, Vice President of the Southern Railway (U. S.) for presentation at the International Railway Congress in Berne, Switzerland in July, I9IO. That report has already been printed, and so thoroughly covers the subject involved that there is very little left to say. The further discussion of the matter during the proceedings of the Berne Congress in July, when published, will presumably furnish some additional informa- tion, or be the means of throwing a side light upon some of the technical questions at issue. There may, however, remain a few points here and there which might, perhaps, be presented from a new or different point of view. The development of perishable freight traffic in Amer- ica is very rapid and, therefore, encourages inventive genius and gives rise to many changes of method from time to time. So true is this that even the relatively short period of six months or a year brings into prominence new apparatus or new practices. These innovations, together with a general summary of the methods now employed and the desiderata as to future practice must substantially define the limits of the present paper. The Extent of the Traffic. Much has already been said in the European press about the enorm- ous quantity of fruits, vegetables, meats, fish, game, butter, eggs, cheese and other perishable commodities transported in America. Those in- terested in this subject are, therefore, already quite well aware of the great volume of this business in the United States, Canada and Mexico, involving as it often does very long hauls of two thousand or three thousand miles. A shipment may originate in the far South or South- east in a warm climate requiring the use of ice in the cars to prevent damage by heat, and that same shipment, during its journey, may pass 1004 through or into a territory where the apposite climatic conditions exist and where the goods would be liable to be damaged by freezing unless protected by artificial heat. These and many other problems greatly complicate the safe transportation of perishable commodities in Amer- ica. The producing fields are often, located at great distances from the consuming markets. This has necessitated the construction of a large number of refrigerator cars, ventilated cars, or other insulated or partially insulated equipment. Many of these cars, of which the number in the United States is constantly increasing, were built by railroad companies, and others by so called private car lines. The private car lines may be divided into two classes, first: those sometimes called semi-private car lines, which are owned or controlled by one or more railroads: second; those called strictly private car lines which are not owned or controlled by railroads. A careful calculation was made in 1908 to determine the total number of refrigerator cars equip- ped with ice tanks, also total number of ventilated cars or fruit cars without ice tanks. Of that investigation a summary is given below:— Owner Refrigerator Cars Ventilated Cars or with Ice Tanks Fruit Cars with- out Ice Tanks. Railroads 29,652 49,274 Semi-. Private Car Lines.................... 26,934 ---------. Strictly-Private Car Lines.--------------. 28,857 ~~~~ 85,443 49,274 The above figures are approximately correct for the year 1908, but since that time a considerable number of refrigerator cars with ice tanks has been constructed by railroads or car lines, and it is reason- able to believe that there are now about IOO,OOO of such operated in the United States, Canada and Mexico, to which must be added about 50,000 ventilated cars or fruit cars without ice tanks, which are, never- theless, designed for the handling of perishable freight, making thus a grand total of about 150,000 cars especially constructed for this traffic. These figures showing the number of cars in use will perhaps give a better idea of the volume of the traffic than to attempt to furn- ish statements of the actual tonnage of the different commodities trans- ported; in fact no complete statement of the latter character is ob- tainable because the different carriers have not kept their statistical •ecords in a uniform manner as to the various commodities handled. It may be remarked in passing that some of the principal American railroads, such as the Illinois Central for example, transport one mil- lion tons or more of perishable commodities in a single year. The 1005 volume of such traffic in America is constantly increasing for several fundamental reasons. In the first place there is each year an increas- ing amount of land made available for agricultural purpose and the farmers are finding it more and more desirable and profitable to diversify their crops. It must be added that the railroads themselves, by adopting a liberal policy, are entitled to a very large share of the credit for increasing the production of fruits and vegetables. The railroads have, at great expense, supplied service in new territories and by giving this assurance of the necessary facilities have greatly encouraged producers, who have thus the certainty that their products will be safely transported to the consuming markets. Incidentally it should be stated that fresh milk in cans is trans- ported to the large cities, ordinarilly in baggage cars on passenger trains without the use of refrigeration, but some railroads have con- structed a few refrigerator cars for movement on passenger trains. Some of these cars are equipped with shelves or double-decks, upon which the milk cans can be placed and securely braced to prevent them from falling over in transit. Some of these refrigerator cars handling milk are refrigerated by the use of ice put into the bunkers of the cars from the outside in the usual manner, but it has been suggested that, for short distances, say fifty or sixty miles, particularly in the far south where the weather is very hot, it might be a good plan to place large tanks partially filled with cold water and ice so that the milk cans could be conveniently deposited therein to secure refrigeration in transit. It has been thought that this latter plan would be more economical and less, difficult than the ordinary method of refrigeration by the use of ice in the tanks at each end of the car. Construction of Refrigerator Cars. There is a great difference in the design and size of the various refrigerator cars used by American Railroads, and this is true of almost every detail of the construction, including, in fact, the ice tanks themselves, which have a varying capacity for ice ranging from 4000 pounds to IIOOO pounds per car. In the building of new cars there is decided tendency towards the larger tank and in the direction of increased insulation of the walls, roof and floor of the car to prevent excessive meltage of ice and thus economize refrigeration. Among the most recently constructed refrigerator cars are those built by the Pacific Fruit Express Co., of which Mr. C. M. Secrist is General Manager. We present, therefore, some facts and figures supplied by Mr. Secrist in March, 1910 as follows:— 1006 . “I quote below exact information as to inside and outside measurements of cars above referred to, also total cubic capacity as well as capacity be- tween ice tanks: Gauge 4° 28%" Length over sheathing 40' -11.3% “ Length inside of lining 39’ –10%." Length between ice tanks 331 - 2% “ Width inside of lining - 87 - 2%.” Height, top of floor to ceiling 7" - 55%;" Total cubic capacity...... 2,444 cu. ft. Available cubic capacity between ice tanks 2,032 cu. ft. Capacity of both ice tanks 11,000 lbs. Length over end sills - 40' -9% “ Length, inside to inside of coupler knuckles........................ 43’ -9% “ Length over couplers ! 44' -3% “ Width over side sills 9' -1.3% tº Width over sub side sills 9’ -1.1% tº Width over sheathing.......................... 9' -2% tº Width over eaves - ---, 9' -6 tº Distance, center to center of body bolsters............................ 30° -S." Truck wheel base 5' -64 Total wheel base..……. 36 -2” Height, top of rail to center of couplers 34% tº Height, top of sill to bottom of side plate................................ 71 -1133 tº Height of side door opening........................................................ 5' -97% “ Width of side door opening.......................................................... 4' -0" Height, top of rails to eaves ------------------------------------------ 12 -3}} tº Height, top of rails to top of brake shaft 13’ -5 §§ 1. Height, top of rail to top of running board 13' -0% tº Light weight of each truck, about 6,066 lbs. General weight of car complete, about 46,800 lbs. These cars are equipped with Bettendorf underframe, which is of steel construction throughout. Linofelt insulation is used in the cars, being applied in three ply form, that is, three courses of insulation on top or ceiling, the same on sides, ends and floor of car. We find this to be ample protection from heat or cold. We also find that the collapsible tank is giving entire satisfaction in every respect. The additional loading space obtained by raising bulk heads, figures about 15%. You will note from the general description that the total cubic capacity of the car is 2,444 cubic feet, while the available cubic capacity between ice tanks is 2,032 cubic feet, the difference between these figures being about 16.85%. However, the bulk-head when raised against ceiling, occupies some space, so we figure about 15% is a fair estimate, The present standard carload of citrus fruit is 396 boxes. As an indica- tion of the loading possibilities of these cars with the bulk-heads raised, we have had loaded out of California, one car containing 468 boxes of Oranges and another containing 635 boxes of oranges. Admitting that the latter load is an extreme case, yet, after proper allowance is made therefor, it can be * * 1007 appreciated readily that there is ample space remaining for large increase over the standard load of 396 boxes. We have received a great many favorable comments on our car and consider it as being the ideal refrigerator car.” The Santa Fe Refrigerator Despatch Company, of which Mr. . J. S. Leeds is the Manager, has also constructed some new refri- gerator cars of an improved design, which are described by Mr. Leeds as follows:— r “Attached is a description of our newest refrigerator car, series 72.01 to 8250: . INSULATION Roof %” Flax Felt—3 Ply ~~3 ply 90 lb. Neponset Paper % “ Ship Lap—2 Ply on each side of Flax Felt %" Ceiling T1oor %” Flax Felt—3 Ply (3 Ply 90 lb. Neponset Paper, etc.) 1%" Ship Lap Flooring %" Ship Lap 3 Ply Sides ##" Siding % Furring 2 Ply % “ Ship Lap ; : %” Flax Felt—2 Ply (3 ply 90 lb. Neponset Paper, etc.) : ##" Lining Ends Same as Sides Doors %" Flax Felt, 2 ply inside doors. La Flare patent insula- tion for door joints. Hatch Plug %” Flax Felt, 2 ply, with 3 ply 90 lb. Neponset Paper on each side of Flax Felt. Are attached to ventilators and are operated, open and closed, with lever on ventilator MEASUREMENT Tanks Down Length—33’ 5% “ Width–8' 2% “ Height—7’ 3” Tanks Up Length—39’ 8% “ Width–8' 2% “ Height—7’ 3” RO OF \ Flexible outside metal roof No. 26 gauge galvanized iron. COLLAPSIBLE ICE TANKS Ice box pans and sides 3' 11" from floor made of No. 20 galvanized iron; No. 24 galvanized iron above 3' 11" high on sides; No. 20 galvanized iron in ice hatches. 1008 You will note that I have given the various dimensions, etc., which you will probably desire. These cars are equipped with collapsible ice tanks. It will be noted that the loading space with the bulk heads down (or so equipped that ice may be used in transit) is 33 ft. 5% in. With the bulk heads raised (when car is to be used under ventilation), the loading space is increased to 39 ft. 8% in. The great advantage of increased loading space of cars under ventilation can at once be seen as compared with the old style. ice bunker, which was permanent. - These cars are equipped with Bohn patent ventilators which are operated, opened or closed, by means of levers, one attached to each ventilator. This is a great advantage over the old style ventilator which required a large amount of labor in order to adjust, on account of the necessity of pulling heavy ice plugs up from the bottom of the ice tanks when placing them in position, when it was necessary to close the ventilators, and reverse the operation when opening the ventilators. This feature will not only save a lot of unnecessary labor in handling ventilators on cars in transit, but will materially cut down delays on the road, caused by the necessity, in many cases, of placing trains on the side track in order to manipulate the ven- tilators when weather conditions necessitated. The capacity of the ice tanks of these new cars is 10,000 pounds, (each tank 5,000 pounds.) The cars in this series have steel underframes. We consider them strictly up-to-date in every respect and the best refrigerator cars we have yet had in our service.” Still other transportation companies in the United States, dur- ing the last year or two, have built new and improved refrigerator cars with increased insulation and with large ice tanks An American manufacturer of insulating material has recently constructed a car for exhibition purposes which is equipped with four ply insulation in the walls, roof and floor, and is provided with a new style of folding or collapsible ice tank in each end of the car, which can be opened or closed by One man without assistance. In the bot- tom of each ice tank is a newly invented non-Splashing drip pan, which is intented to prevent the water from Splashing back and forth, which has, in the past, caused damage to goods contained in packages loaded near the ice tanks. Furthermore, this new car, which is a very in- teresting example of modern equipment, has a weather-proof ventilat- ing apparatus acting as a combination hatch-cover, hatch-plug and vent at the top of each end of the car, permitting the entrance of a considerable volume of fresh air down into the ice boxes and through the car, thus insuring a good circulation of air around and through the lading. This new car was designed with the intention of removing several of the principal causes of damage to perishable commodities in transit. 1C09 Use of the Refrigerator Cars. Generally speaking the refrigerator cars, regardless of precise ownership, are supplied to shippers for loading without any special rental charges being assessed. In other words all compensation as rental of cars is paid to the owners by the railroads using such cars. Refrigerator cars belonging to and operated by railroads are subject to what is called a perdiem charge, which at the present time is 25 cents per car per day on all classes of rairoad equipment, but all the private car lines, whether operated by railroads or by other corporations, receive a rental charge based ordinarily upon one cent per car per mile whether the car is loaded or empty. The Interstate Commerce Law and the rulings of the Interstate Commerce Commission contemplate that all railway cars, regardless of exact ownership, are instrumentalities of transportation when in that service and are, therefore, to all intents and purposes, the property of the common carrier during the period of movement over the rails thereof. The law in the United States requires that common carriers shall furnish all necessary equipment, cars, refrigeration, icing, ventilation, and other instrumentalities of service. Therefore, if a common carrier makes a private contract of any kind with a car line to supply certain equipment, that equipment, while engaged in transportation, is subject to all the rules, regula- tions, conditions and privileges applicable in connection with the use of any other equipment of which the absolute ownership is vested in the common carrier. The only distinction is as regards the man- ner of compensation to the owner for use of his equipment, but this does not materially effect the shippers or consignees. Loading and Stowing. The shippers themselves or their own agents are generally speak- ing, responsible for proper loading, stowing, bracing and stripping of freight. On which carload rates are assessed, and it may be added that such freight is unloaded by or for account of the consignee at destina- tion at his own risk and expense. The shippers, however, are ex- pected to load fruits and vegetables properly and with due regard to the circulation of air between the packages to prevent over-heating. All the experienced shippers, therefore, are careful to see that the neces- sary strips are placed between the packages to permit the circulation of air, and that the packages are securely braced to prevent shifting in transit, which might result in breakage with damage and loss. The railroads attend to the loading, stowing, bracing and un- loading of Small lots of freight on which the less-than-carload freight rates of transportation are assessed. *Y 64 1010 Demurrage Charges at Destination. Subject to certain conditions and exceptions the consignees at destina- tion are allowed forty-eight hours in which to unload cars, but if they postpone the unloading beyond that time they are obliged to pay a demurrage charge of One dollar per car per day, exclusive of Sun- days and holidays. The Governmental authorities and the courts have realized that this demurrage charge is based on good public policy, because it encourages the prompt release of equipment and permits the railroads to return the cars into regular transportation service. The consignee of fruits and vegetables in refrigerator cars receives, however, much greater benefit from delaying the unloading of such cars than the consignees of any other commodities. Therefore, the rdinary demurrage charge of one dollar per day is not sufficiently high to insure the prompt release of refrigerator cars by consignees, who delay the unloading awaiting higher market prices or to avoid the expense of hauling the goods to their own stores or to public warehouses. In fact the consignees in this way often escape the pay- ment of heavy charges for cold storage in the regular warehouses. The best public policy requires that refrigerator cars be promptly released and returned to transportation service, and such additional charges as may be necessary to accomplish this desideratum should be adopted and assessed. There seems to be a growing sentiment in favor of such action, and if such charges should be adopted, they would not necessarily work any hardship whatever against the average consignee, who unloads his car within a reasonable time. Such ad- ditional charges would be paid only by the consignee who tries to use a refrigerator car as a warehouse. - Initial Icing of Carload Lots. While the Interstate Commerce Law requires the carrier to fur- nish the necessary refrigeration or icing in transit, it does not ex- pressly throw upon the initial carrier the duty of performing the initial icing at the time of loading. Therefore, in many cases, the shipper does own initial icing unless the initial carrier publishes a tariff nam- ing through refrigeration charges from loading station to destination In this latter case the initial carrier would itself perform the first icing of the car. There are some instances in which the shipper does the initial icing with the expectation the car will go through to destination without any further icing, and he thus escapes the expense of any reicing in transit. There are some strong arguments against that practice, because it results in divided responsibility. 1011 Reicing Carloads in Transit. With very few exceptions the American railroads handle exclus- ively the matter of reicing carload lots in transit. In cases where the railway tariffs provide icing charges per ton it has been customary to allow the shipper to give instructions as to where he wishes to have the cars reiced, and with what quantity of ice. . When, however, the railway tariffs name through refrigeration charges applying from loading station to destination, the carriers are at liberty to use their own judgment, and are, of course, very careful always to use Suf- ficient ice to protect the property safely while in transit. The applica- tion of through refrigeration charges is so much more satisfactory in every way that there is a rapidly growing sentiment among American railroads against the use of icing charges per ton. It is thought that perishable freight should move either under refrigeration or ventila- tion, and if moving under refrigeration the carriers ought to be free and untrammelled in exercise of their right to use sufficient ice to protect the property and prevent damage in transit. One of the most interesting features of refrigeration work on American railroads is the apparatus employed for reicing in transit. The railroads either own and operate their own reicing stations in transit or make contracts with ice dealers for that purpose. In either ase, particularly in the northern states where crushed ice and salt is ex- tensively used, the work of reicing is done with extreme rapidity. A train of thirty or forty cars can be placed at an icing station and the ice bunkers fully replenished with ice within a period of time not ex- ceeding two minutes per car, when the train is ready to proceed on its journey. This rapid work, made possible by special apparatus, is necessary, owing to the great distances traversed. A good descrip- tion of a modern reicing station with illustrative drawings was con- tributed by Mr. W. J. Frein to the proceedings of the Paris Congress. Up to the present time the American railroads have almost ex- clusively used either natural or artificial ice to secure refrigeration in transit. Some experiments have been made with mechanical re- frigeration, but there is the serious objection that a competent me- chanic must be sent along in charge of the apparatus. There is also the further objection that such a car with mechanical refrigeration, if set out of the train at any point in transit, or even on arrival at destination, might cease to be refrigerated, and damage to the perish- able commodities therein might result. These obstacles Surrounding the use of mechanical refrigeration in America have not yet been sur- mounted. A very few experiments have also been made with liquid air. 64% 1012 Icing and Reicing of Pick-Up and Peddler Cars. The remarks above made about initial icing and reicing of carloads in transit do not include cars loaded with small lots of perishable freight from various shippers to the same or different consignees. When several shippers are interested in the contents loaded into a single car it would be somewhat difficult to divide or pro-rate the cost of icing such a car. Furthermore the freight rates of transportation for small lots are, of course, higher per hundred pounds than the rates applying on fully loaded cars. It has been, therefore, the general prac- tice of railroads to absorb the cost of icing out of their own earnings, based on the freight rate assessed for the transportation of the prop- erty. This is true also of cars loaded by one shipper to one consignee on basis of the published minimum weight of, say, Io,000 pounds or 15,000 pounds per car, in connection with the so-called less-than-car- load freight rate, which, as above explained, is higher than the carload rate. It might safely be stated, therefore, that, as a general thing, the shippers pay some kind of an extra charge for icing and reicing car- loads, but they do not ordinarily pay any extra charge for the refrige- ration, icing or reicing of perishable freight on which less-than-car- load rates are assessed. The word “carload”, however, is not synonym- ous of the expression “loaded car.” That is to say a carload, from a Traffic Department standpoint, is a shipment on which the carload freight rate is assessed. We might have a fully loaded car contain- ing Small lots of perishable freight from various shippers, but such shipments would be assessed at the less-than-carload rating, and if the car contained the established minimum weight of Io,000 pounds or more there would not be any extra charge made for any necessary icing or reicing in transit. Enormous quantities of eggs, butter, cheese and dressed poultry from points in the states of Illinois, Wisconsin, Iowa, Missouri, etc., are handled in this way to New York City, Boston and other eastern markets. Some shippers of Oysters in Small lots make use of a vacuum car- rier, which is constructed on the principle of the thermos, bottle. The lid of this Oyster carrier has a glass top and is especially designed to hold a small cake of ice, which melts very slowly. The oysters are, of course, first precooled to a temperature of about forty degrees Fahrenheit before they are put into the carrier for shipment. Importance of Uniform Rules. The great extent of perishable freight traffic in the United States, its constantly increasing in importance and the value of the property handled, have made manifest the need of uniform rules. The prin- 1013 cipal railroads in America transporting perishable freight proceeded, therefore, to organize the Railroad Refrigerator Service Association, which was established Feb. 5, 1908, with an initial membership repre- senting about 90,000 miles of railroad. The present membership of that Association is (May, 1910) almost 145,000 miles of road. The membership is constantly increasing owing to the useful and practical work already accomplished by that organization. Among its first steps was the compilation of a code of standard rules known as its Circular No. 27-A, which covers every conceivable emergency in connection with the refrigeration, ventilation, heating or other handling of perish- able freight by transportation companies. About 45,000 copies of these uniform rules are now distributed and used by the railroads of the United States, Canada and Mexico. Other railroads from time to time are adopting the uniform rules, and it seems reasonable to believe that, in due course of time, their application will become universal, for they have been found productive of good results and have greatly aided to increase the efficiency of service and, therefore, reduce the number of damage claims. The Railroad Refrigerator Service Asso- ciation gives every promise of becoming one of the most useful organi- -zations formed by the transportation companies of America. Local Inspection. Practically all the railroads in America transporting perishable freight have some system, more or less extensive, whereby local agents or other employes at loading station, also at stations in transit and at destination, inspect cars containing perishable commodities. This in- spection, in some cases, may be confined to the car itself and its appur- tenances such as the ice bunkers, drain-pipes, drip-cups, ventilating devices, etc. In other cases the inspection may, perhaps, include Some examination of , the goods loaded into the cars. It is generally the practice to make an examination of the contents at any point in transit where there is indication of the car or contents having been damaged. A careful record is made and preserved permanently at such stations, showing the details of inspection made of each car. Best results are obtained by designating some One employee at each station as being pri- marily responsible for the proper supervision of perishable freight. He may, of course, require several assistants to perform the actual work of inspection, icing, etc., if the volume of business handled at that station is very large, but he can, nevertheless, exercise general supervision over all the work and see that the requirements of the ser- vice are thoroughly understood and that the necessary rules are en- forced. 1014 Supervision by General Office. Many of the larger American railroads maintain a special depart- ment or bureau and in some cases a subsidiary organization to look after all the details of perishable freight service to see that the agents, yard clerks, freight conductors and others concerned understand the requirements of such service and properly perform their duties, relat- ing to icing, reicing, ventilation, heating, transferring or other handling of that traffic. Such departments or bureaus receive complete reports daily or frequently from the agents at points where cars are iced or inspected. These reports, when received, are carefully examined and Ought to be cross-checked against each other to determine whether agents and other employes are giving the proper attention to each and every car, not only at loading stations and destination, but at the prin- cipal points in transit. These reports show amount of ice in the tanks as well as the amount of ice, if any, added, and the condition of drain- pipes, drip-cups, etc., also the position of ventilating devices, that is, whether they are open or closed. This inspection in some cases is ex- tended to include an examination as to the exact condition of the per- ishable commodities loaded in the car, particularly if there is any vis- ible indication of the car or its contents having been damaged. The general Office exercising this supervision not only examines very closely the reports made, but studies the whole situation with the constant view of reducing the number of damage claims and of bringing the service to the highest state of efficiency. Such a department or bureau on One railroad must keep in close touch with similar organizations on other railroads to watch closely the progress of invention and the adoption of new improved or more economical methods of service. Assistance of the United States Government. In keeping with the liberal policy adopted by the United States Department of Agriculture, the Bureau of Plant Industry has, during the last few years, performed a greatly needed and very beneficial work in the way of investigations as to the best methods of picking, packing, loading, stowing, bracing, icing and other handling of fruits and vege- tables. A large part of this work has been done under the personal supervision of Mr. G. Harold Powell, the eminent pomologist, who has spent considerable time, for example, in California, to bring about the better handling of Oranges, lemons and other fruits and vegetables produced in that state. Mr. Powell's investigations have, of course, been extended also to other section of the country with excellent re- Sults. Shippers, who had not previously exercised much care in pick- ing or packing of fruits and vegetables have been made to appreciate 1015 the better market prices which are obtained for goods properly picked ańd packed. Mr. Powell's extensive experiments have established many important facts which have a great influence on general improve- ment of the service as a whole. As stated in the beginning of this paper the enormous volume of perishable freight traffic in the United States has necessitated very close study of the problems involved, and constantly encourages the invention of new apparatus, which, generally speaking, is promptly tested to discover its real or relative merits. We have already men- tioned, in connection with the construction of refrigerator cars, the new collapsible ice tank, which results in a substantial saving of load- ing space when cars are not to move under refrigeration. Another important question, even in connection with refrigeration, is the venti- lation of cars loaded with fruits and vegetables, for it must be admit- ted that when such commodities are loaded into a refrigerator car they contain considerable field heat which cannot be eliminated for many hours by ordinary use of ice in the tanks of the car. Therefore, the field heat continues to exercise its tendency towards decay of such pro- ducts for many hours, after the car goes forward under refrigeration. Attempts have been made to increase the amount of refrigeration or to hasten its action by leaving some of the ice plugs out and the hatches Open to permit the entrance of air into the car through the ice tanks, but this results in meltage and waste of ice and is a very uneconomical practice. Trouble also frequently results from the fact that cinders and other foreign matter get into the ice bunkers through the open hatch- ways. Various attempts have been made to invent and adopt some ven- tilating device which would accomplish the desired purpose of increas- ing the refrigeration and hastening its action without permitting cin- ders to enter the car. There is also the problem of removing from the car the gases emanating from the fruits and vegetables. The exhaust- ive paper by Mr. J. M. Culp, which has already been mentioned, de- scribes in detail the Garland Ventilator, which has been adopted quite generally on many passenger coaches, as well as on Pullman sleeping cars, and has also been applied to a considerable number of refrigera- tor cars constructed by the Santa Fe and other railroads. Some changes have been made in the Garland Ventilator since Mr. Culp's paper was published. The new design of that device has a small hood or intake at the top of each end of the car with a view of forcing a strong circu- lation of air down into and through the ice tanks and ultimately throughout the car, in the roof of which are placed two outlets, either of which can be opened or closed by one motion. It is very desirable 1016 to Ilave refrigerator cars equipped with standard thermometers, indicat- ing the inside temperature of the car to be read from the outside with- Out Opening the car. * Some fruits and vegetables, such as tomatoes, for example, are picked, packed and shipped before they are ripe. In many instances the tomatoes are wrapped in paper and are sent forward under venti- lation without the use of any ice. The tomatoes are supposed to ripen in transit, and if the ultimate destination is located at a great distance, say 2,000 miles, from loading station, the shipper will make arrange- ments with the railroad whereby such a car will be initially iced at some point in transit, say three or four days after it was loaded. This icing of course, tends to prevent the tomatoes from becoming too ripe before reaching destination. It would, of course, be impossible to ship abso- lutely ripe tomatoes or other fruits to far distant markets, with the ordinary use of ice in tanks. There is, however, a wide and rapidly growing interest in the methods of precooling, which seem to be based upon the correct prin- ciple. The Southern Pacific Railway, after extensive experiments dur- ing the past few years, has adopted the Intermittent Vacuum Precooling Process and at great expense has constructed some large precooling plants in California. The Santa Fe Railroad has also been making some . experiments with a precooling process and intends to establish a pre- cooling station at San Bernardino, California, early this year (1910). Some negotiations are also being made for the erection of two or three precooling plants at points in Georgia and Florida. As the whole sub- ject of precooling will be very ably presented at the Vienna Congress by Mr. S. J. Dennis of the United States Department of Agriculture, it is not necessary for this paper to discuss that matter. It is obvious that the principles of precooling have much of practical value to com- mend them and it seems quite clear that such methods will be more generally adopted in the near future, particularly if the necessary plant with machinery and apparatus can be obtained at a reduced cost and can be operated economically. The precooling of Strawberries and other delicate fruits, also tomatoes, fully matured and riper, would naturally conduce to the placing of such goods upon the market at destination in much better condition for consumption than any other methods of re- frigeration so far employed. * It must be said in conclusion that there is still a glorious future for refrigerator transportation in America because of the rapid and never ending increase in production of fruits and vegetables and the increase in population of the country as a whole. New lands are being 1017 opened to the settler and to the farmer each year. The adoption of new and better methods of handling the goods encourages the producer to devote more of his attention and energy to the cultivation and shipping of fruits and vegetables; the irrigation of vast tracts of desert land have created, as it were, new and fruitful fields of enormous acreage. All this tends to a wonderful development of the perishable freight traffic in America, which has always been and no doubt always will be closely fostered by the transportation companies, who have spared no trouble or expense in furnishing the necessary facilities to handle it. No man can prophesy the ultimate result, but clear it is that the pro- duction of fruits and vegetables in America, notwithstanding its present greatness, is only in its infancy. 1018 Refrigerated Railway Transportation. By dipl. Ing. Rich. Stetefeld, consulting engineer, Pankow-Berlin. From the report made to the II. International Congress of Refrige- ration, in Vienna, by M. Richard B 1 och, Ingenieuren Chef de la Cie. des Chemins de Fer d'Orleans, we learn that cold storage transport on railways has attained to great economical importance in the western continent of America — in the United States alone over 60,000 refrigeration cars are constantly running. In our eastern continent, however, especially in old, historical Europe, a great want exists of the application of this most neces- sary form of transport for food articles. According to the above report there are, excluding Siberia, but 1085 refrigeration cars in use. Of this small number, moreover, but 421 cars belong to industrial Germany. Of these 421 cars 272 belong to railway companies and 148 are privately owned. They are employed as follows. 150 refrigeration cars for the transportation of beer 153 X. X X X. X », butter 65 > X X X X » milk 2O X X X X X). » herrings and other sal– ted fish; and only 15 > X X > X » fresh meat ! O X X X X) X » artificial butter etc. That so small a number of cars are for meat transport is perhaps chiefly due to the impracticability of conveying meat for long distances with ice cooling alone, while in Germany such cooling is almost the only method in use. It is also remarkable that in all refrigerating cars running on German railways, not one is specified for the transport of fruit and vegetables. So far as my knowledge goes, a small number of such cars do indeed run, but far too few for the extensive fruit and vegetable transport in and to Germany. Here, again, the chief cause is to be sought in the fact that while on the one hand simple ice cooling, without any chemical addition does not completely satisfy all requirements, one on the other hand fears to install the comparatively expensive apparatus necessary for machine cooling. This is in great part due to ignorance. For cold storage transport on railways three important conditions must be striven for: 1019 1. The most complete arrangement possible at moderate cost. 2. Smallest possible working expense. 3. Endeavors through united requests of parties interested, to get the cost of transport cheapened by urging German railway administrations — like many foreign railway administrations, c. g. those of the United States of America, Canada, Hungary, etc., to make more favorable regulations, under which the transport of perishable food products will be effected more cheaply and quickly, and with cooling apparatus, the dead weight, for instance, of such apparatus together with the ice filling etc., and its return transport to be entirely freight free, or at greatly reduced tariffs. -- According to this triple division it has been endeavoured in the fol- lowing to explain ways and means that may serve towards the attainment of the objects mentioned. I. Technical arrangement of Refrigerator cars. The technical measures for cooling railway cars for food transport may be of three kinds: 1. Ventilating; 2. Cooling, both ice-cooling and machine cooling; 3. Cooling and ventilating combined. - While in machine cooling the necessary air drying takes place simul- taneously and automatically, with ice cooling the air drying can only be effected by adding moisture absorbing chemicals to the ice. A. Refrigerator cars with ice-cooling. Refrigerator cars with pure ice filling and without airing can only be recommended for transporting beer and milk in closed vessels. For unpacked food which can be affected by the air in the cars, the air must be relatively dry and from time to time replaced by fresh, precooled air from outside. B. Refrigerator cars whith ice-cooling and ventilation. The refrige- ration cars with ice filling and airing are the only type used in Germany for transporting meat, live and dead fish, butter, cheese, fruit (this latter indeed mostly in ordinary wagons without cooling), vegetables, and other goods machine cooling being still anxiously avoided. The shortness of German railways, as compared for instance with those of Russia, America and some other countries, will probably be given as reason for this, as the time of transit being shorter, ice-cooling combined with airing would appear to be sufficient. In this case, however, it is necessary to endeavour to attain perfect means for ice-cooling. This point will be mentioned again later on. g Two examples are given of wagons with airing and ice-cooling of German manufacture: One wagon for transport of live fish, and one for fresh meat or other perishable food stuffs. *- SN § § Fig. 1. The floor of the car is 168 sq. m. for 10 and 12.5 tons, and 20 sq. m. for 15 tons load. The inside fittings of the cool wagon for the transport of live fish may be seen from the accompanying Fig. 1. In the fish room 24 movable fish tanks a are arranged on the side walls, and are secured by means of suitable apparatus. A water conduit system & sunk into the floor of the car, con- nects the fish tanks with a reservoir c. A rotary pump d, . driven by a benzine motor, keeps the water in constant circulation. This is the old method of maintaining fish alive in tanks, for long periods, by means of a jet of water, which upon being forced into the tanks, continually carries air with it and thus aerates the water. - - Fig. 1 and the foregoing description explain the cars built by the Düsseldorf Railway Requisites Com- pany, formerly Carl Weyer & Co., at Düsseldorf-Ober- bilk. - . During the cooler seasons the arrangement described suffi- ces alone for preserving fish alive during long transport. For summer seasons a cooling apparatus is added, in the form of one or more ice vessels f fixed on the inner walls of the car. . . * The Düsseldorf wagon fac- tory arranges refrigeration cars 1021 for other purposes also, e.g. for the transport of beer, meat, butter, vegetables. The insulation of the walls of the car is done very carefully. It consists of a triple casing of wood with insulating layers between. The ice vessels are constructed to hold 600 to 1000 kg. ice, and are provided with all possible arrangements for carrying off the water from the melting ice. The cars are also fitted with apparatus for introducing and expelling air. This apparatus may be partly seen in Fig. 1. Fresh outside air is constantly introduced by admission devices operating in connection with the ice tanks, and it passes in cooled state, to the food stuffs in the cars. After passing these the air is expelled through the air outlet g, in the roof of the wagon. Experiments made some years ago by the wholesale fishmongers. Jacob Brothers in Berlin led to the knowledge that, in transporting live fish, Fig. 2. not only constant renewing of the water is of importance, but also the effective aeration of the water in which the fish are. The Berlin firm men- tioned, recognising this fact, together with the engineer for the Press Air Industry, A. Serenyi, formed a somewhat different method for the trans- portation of fish, and placed it on the market under the name of Der Preſs lufts tabs (Compressed air). Into this distributor, which is fitted to a pipe, a pump drives the air or gas at any desirable degree of density so that the air or the gas, at a pressure suitable to the particular purpose streams out and rushes upwards through the liquid to its surface. To secure a complete aeration of the water the compressed air distributors must lie on the bottom of the tank, and the air must be at such a pressure in the distributors as is greater than the weight of the liquid above them. This apparatus by Jacob and Serenyi is shown in Fig. 2. ~. Air is drawn by the pump 6 through the filter a and compressed into the air chamber c. From this it is conducted through distributing tubes d and adjoining branch conduits to the compressed air distributors on the floor of the fish tanks. The fresh air, in finest distribution, streams out of these into the water and rises to its surface. It is quite easy, with the aid of the valves inserted into the pipes to control the flow of air to the individual tanks at will. The air pump may be belt driven from an axle of the car, or it may be driven by a small motor f. The first method is cheaper but it is de- *-> E: pendent upon the movement of the Fig. 3. Refrigeration car for meat transport. wagon. In order therefoire that the operation may not cease during long stops a motor will be indispensable. The firm named have found that tanks provided with compressed air distributors can not only contain more fish, but can also be employed for longer journeys. Such have repeatedly been made for as much as 82 hours with the greatest success. Zºzº, 2//// H - In " ( ) /ī/. A. ſ ) N. _2^ S. . . ~ Refrigeration car for meat transport. (Fig. 3 and 4.) - The wagon serves to keep perishable objects (especially meat) cool and well aired during transport. It represents the style of building of the W a g g on fabrik Akti enge sellschaft Rast att, - To cool it the car is provided at each end, with a roomy zink lined sheet iron tank. The air entering behind this is cooled by passing along 1023 its sides, and is then conducted into the interior of the wagon. The bottom º of the ice vessel is an iron grating 3, so that here the air can also come into immediate contact with the ice, such part of the air being thus greatly cooled. The air enters through the automatic ventilator c (see top right hand corner of Fig. 4 horizontal section), and can be controlled by the slide valve d. The air then passes partly under the ice tank and partly through the grating 6, which is filled with ice. The exit takes place through the clackers e, gutters f are placed before these clackers to hold chloride of calcium so that, if necessary the air may be dried thereby. The ice is filled in through the roof opening g. The air passes through the whole car and is sucked off by the ventilator /. É r 'er # 5 tº --> Cr- f: 2: º 'Cº. Cr- * fºax G- Käºstºniuſ - Fig. 5 a. (Sketch.) &mpresstræn. Motors. tº: Fs—e \ Fig. 5b. (Ground-plan.) Refrigerator car with machine cooling, or refrigerator train after - the system of the Gesellschaft für Linde's Eismaschinen A. G. Meat is hung during transport on the hooks 7, So that cool air plays round all the meat. Thaw water is led through small pipes & into a gutter /, and led on through condensation pots m. The walls of the wagon are well insulated and coated on their out- side with a coating of light colored paint to check the heat absorption. - C. Refrigerator cars with machine cooling. Refrigeration cars, or whole trains with machine cooling are made in Germany (though not for Germany but rather for Russia) by the Gesellschaft für Linde's Eis- maschinen A. G. at Wiesbaden and by the Masch in enbauan stalt Humboldt at Cöln-Kalk. - 1024 In the years 1901/02 the Gesells ch a ft für L in de's Eis- masch in en A. G., at Wiesbaden, in conjunction with the Rigaer Eisen- giesserei and the Masch in en fabrik Felser & Co. at Riga planned a refrigerator train with machine cooling and carried the plan into execution. It was laid down according to the programme that one machine car and five refrigeration cars should be provided, which should later be so put together that two refrigerator cars should run on one side of the machine car and three on the other side. Fig. 5 shows the machine car in horizontal and vertical section. Fig. 6 shows a part of the complete refrigerator train. A Petroleum motor was chosen for the driving power, and the cooling was effected by the practical roundabout salt water me- thod. Fig. 5 shows the motor with water back cooling apparatus and Petro- leum reservoir, the ammonia compressor, the drizzle condenser with venti- Fig. 6. Part of a Refrigerator Train. lator for its vigorous airing, the salt water cooler with ammonia vaporiser and stirrers fitted, and the centrifugal pumps for the circulation of the drizzlº Coºling-water and the salt water. A room for the machinist con- taining bed, table, cupboard, and washstand is built in front of the machine room. Under the floor of the car in the centre of the frame is the reser- voir for the cooling water from which the drizzle pump sucks and into which the cooling water can flow back again from the collecting vessel of the condenser, It has proved advantageous to fix the machines and appa- ratus directly on to the frame of the wagon. To exclude the outside heat cork slabs were made use of between wooden casing, for the walls, floors and roofs of the wagons. Besides this the wagons are provided with special coverings. As air cooling apparatus brine pipes provided with drip gutters hang under the ceiling. The 2" main brine pipes also hang free under the ceiling. They pass out under each 1025. gable and are connected by rubber tubing. Practical work has proved it to be of advantage to use several smaller pipes instead of one 2* pipe . in each case. The salt water feed pipes are arranged below the salt water return pipes in order that air may not obstruct the flow of the brine. The cold production of the cooling machine was measured in such a manner that 5000 calories per hour were at disposal for each refrigerator car; but in practical working it was found that the amount of cold required was often considerably less, and that apparatus for suiting the amount of cold produced to the temporary requirements was of very great importance. The circumstance that the number of cars necessary is decreased by the greater freight capacity, and the fact that the avoidance of stops for ice replenishing on long journeys greatly lessens the time of such journeys speak specially in favour of machine cooling. By means of carefully conducted trial journeys on which both butter and frozen meat were transported it was proved that the problem of refri- gerating trains has been solved in such a manner as admits of no technical complaint being raised. The working expenses are so dependent upon weather conditions, which vary greatly on long journeys, that in spite of the data at disposal no generally applicable figures can be given. This is especially due to the fact that the amounts for machinist's wages, depreciation and interests are dependent upon whether the cars are much or little used. Naturally, too, the temperature of the refrigerator car, dependent upon the kind of goods conveyed, is of great influence upon the actual working expenses. Regarding the time of transport with laden refrigerator cars, the average cold requi- rement for Siberian conditions may be put down at about 2000 calories per car per hour, including precooling of the unloaded car. This esti- mate however has no great claim to reliability. The mechanical railway car refrigerating plant recently delivered for the Russian ministry of commerce, was installed by the German firm M as ch in en b a u a n sit a 1 t Hu m b ol d t, K Ö l n - K a l k, in a refrige- ration car sent by the Russian Kolomaer Maschinenbauanstalt. The refrigerator car, planned specially for very hot latitudes has a machine room in the centre. Right and left of this room are two refrigerated compartments, in which the most various kinds of foods can be stored. (Fig. 7.) These refrigeration rooms are suitably insulated, so that neither heat nor cold can penetrate to them to any appreciable degree. In summer, during warmer weather, these rooms are cooled to the desired low temperature by the aid of ammonia refrigerating machines in the car. In order that the refrigeration car may also be used in winter, the refrigerating rooms are provided with suitable heating apparatus, which can be fed by a furnace situated in the machine department, so that even during very cold weather the cars may show a temperature that is suitable and according to regulation. - 65 s -ſ'|$. ſ, , E-; }- &izenſ.aſºn ‘l’agger . . miſ ma2chineſſet &laſſeinricºung 244414 &amºped 1704 &ºmina, 44&fi * ©lak. º ...” § 9 f - * &t-a- 3,12tes $1sº: - • *---3 tº * a t-ſt $22. . % a &tx-k tº ~~~~ tº-ft - .* taxes 14- tº--~ *-* }. s ºf:{ <- * ſº§ | :^2%.3%Ží E:#| | | # -- . | iš. sº. Nixº • * * * * #EEE Bº E #Sif - (Nºsteo." AGP J – exception of the Yeast cars. — The lowering of the temperature below that of the surrounding air is effected by placing, in the space for the goods, reservoirs filled with ice, the walls of the car being double or triple to prevent a rise in the temperature. - In order to prevent the confined air from circulating in the spaces between the walls they are filled with straw, shavings, etc. 1054 The cars called 'cool wagons – Nº. 11.901–11904 (fig. 2) — are used for the carriage of different kinds of food stuffs of a highly perishable nature, especially butter. . The ice tanks, placed against the front walls, have a capacity of 2 mº, The space between the outer and inner walls is filled with rattan shavings. Kö, wa & w ran Fieſsc., rnaws Forr W ſo % /o3/9 H 5 M —Masssra e l; 50. A Æ # glº- $º: Eſº-º-º-ºp TT lve rvas a larr, a Sz, reawwa wr, ( Vy Masssrae / ſo. - The following wagons, reserved º exclusively for the conveyance of beer, are arranged in the following manner: - * Capacity of the ice reservoirs 21 mº, - *- fig. III. Nº 5501–5504, Capacity 23.63 mº, Tonnage 8000 kg, Capacity of the ice reservoirs 3 mº; -- - . fig. II. Nº 5505–5508, 5512–5514, Capacity 289 mº, Tonnage 10,000 kg, 1055 . . fig. IV. Nos. 5515–5516, Capacity 37 mº, Tonnage 10,000 kg, Capacity of the ice reservoirs 15 m3; fig. V. Nº. 55.17–5520, Capacity 31.61 mº, Tonnage 1000 and 12.000 kg, Capacity of the ice reservoirs 2:10 m”; $. fig. VI. Nº. 5524, 5525, Capacity 34.5 m", Tonnage 10,000 kg, Capacity of the ice reservoirs 2.4 m3; fig. VII. Nos. 5531—5536, Capacity 40 mº, Tonnage 15,000 kg, Capacity of the ice reservoirs 1-2 m”; N*6470-6475, fig. 1, are used exclusively for the carriage of yeast. They are not fitted with ice reservoirs. As clearly shown in the sketchs particular care has been given to the: ventilation. 1057 Report of Proceedings of Commission V. I* Sitting, 6* October, 1910. The Sitting began at 2:15 p. m. and ended at 4 p. m. President: Ing. Franz Gerst n e r, k. k. Regierungsrat, technical deputy director of the management of the State Railways Company, Austria; Vice- President: Josef B rom ovsky, k. k. Kommerzialrat, Austria; Secretary: Hugo Tsch me 1 it sch, k. k. Oberkommissār, chief commissary of the state railways, Austria. * Chairman Ing. Franz Gerstner (who repeated these and also his later statements in the French and English languages): Ladies and Gentlemen, I beg to introduce myself to you as the chairman appointed to the Vtº Com- mission by the Austrian Geneneral Commission and I ask you in the first place to accept our heartiest welcome. We are proud that the II* Congress of Refrigeration should sit in our capital and we shall endeavour to render your stay in Vienna as pleasant as possibly could be. * I beg leave, first of all, to submit to you my own appointment to the Chair, for ratification. (Cheers and clapping). In the name of the Congress Management, I now beg to propose the following Gentlemen as Honorary Presidents: Prince Roland B on a part e (France), General Alfred de Wen drich (Russia), Professor David de Golo v n in e (Russia), Inspektor Georg L a r S en (Denmark), Staatsrat Schou (Denmark), . Engineer Richard Ste t e fel d (Germany), Agent General T. A. Cog hl a n (New South Wales), Georges V ill a in (France), Director You (France), J. de Lover d o (France), J. I. da Silva - Fre ire (Brazil), Cav. Claudio S e g re (Italy), 67 1058 Engineer Dainello Dai n e l l i (Italy), Engineer J. R. Kreft in g (Norway), Betriebsdirektor (Manager) C. A. v. Kro g h (Norway), E. C. Boys (England), Hofrat Dr. Ludwig Ball a i (Hungary), Koloman v. Szajbe 1 y (Hungary), Dr. Oliver Jacob i (Hungary), T. F. McPike (United States of America. |Cheers and clapping). We now come to the order of our papers and I call on Professor de Golo v n in e for his paper on >The transport of per is h a b le go o dis on Russian -r a il w a y S&. - Professor David de Golovnine (Russia), whose paper published by order of the Minister for the management of railways, on 9 Transports des denrées périssables sur le réseau ferré de l'Empire Russes, had been dis- tributed to all those taking part in the Congress, reads the most important chapters of the publication. These are the statistics explained by numerous cards concerning the quantities of perishable goods for transport that come into consideration, the growth and present extent of this transport, the des– cription of the refrigeration cars destined for it together with the explana- tion of their internal arrangement by means of plans, the arrangements for after-filling with ice at stations on the route by the setting up of ice depôts and their manner of arrangement (sketches) and, further, the laws and regulations made for the arrangement of this transport. Chairman: As no interpretation is desired I open the discussion. Staatssekretär Claudio Segré (Italy) in French: I gather from the excellent statements of Professor de G O lov n in e that the important question of transport over very long distances appears to be solved by making use of ice; this is still the simplest and best cold accumulator. The arrangement of many ice depôts on the Russian and Sibirian railways also encourages the Italian railways, as they have already stated, at the Congress in Paris, to effect similar transport. For example, milk is thus transported from northern Italy to Rome, artificial ice being employed which costs only 33 centimes. Prof. de Golovnine adds the remark that in Russia only natural ice is made use of, because the obtention and manufacture thereof, by means of pouring on water, etc., is exceedingly simple. - Inspektor Larsen (Denmark) in French: I beg the Professor to tell us the weight of ice used per car and the place in the car where the ice is stored (below the roof or at the end of the car). - Prof. de Golovnine: About 650 kilos of ice are used and generally placed at each end of the car. Louis Robert (France): A load of 650 kilos is too small for western Europe; from 1500 to 2000 kilos of ice are requisite here, if the tem- perature is to be kept down to about 3 to 4 degrees above zero, during a 1059 two day's journey. Storing under the roof is in every case the most ad- visable because the cold air streams downwards and the warm air upwards. J. I. da Silva-Freire (Brazil): We generally make use of cars built on the American system which require greater quantities of ice; in con- sequence of the great clear height it is possible to fix serpentines under the reservoir, which lead off the thaw water. Oberregierungsrat Grunow (Germany): In regard to the question raised as to whether 800 kilos of ice would suffice, allow me to state that on the Prussian State Railways state cool waggons run with milk, butter, etc. from north east Germany to Berlin, from north west Germany to Hamburg, Berlin, Cologne, Leipzig, etc. These cars take one to two days on the journey, and the quantity from 600 to 800 kilos of ice has proved sufficient. The cars have double walls, an ice store fixed to the roof, arran- gement for air draught, and painted sides. (A voice: Do the cars remain closed during the whole of the journey?) The cars are partly not opened on the journey and partly are loaded: for the latter case the cars are provided with curtains on the inside of the doors which prevent the cold in the cars from being to any noteworthy extent lessened during loading. Inspektor Ernst Roeszler (Hungary): May I ask what proportion exists in the refrigerating cars during transport of meat between the weight thereof and the dead weight of the car, or of the ice, seeing that probably in Ger- many also the meat is hung up and not laid in a heap, so that, in the best case, only fron 250 to 300 kilos could be loaded per square metre of floor surface. - Prof. de Golovnine: They are 15 ton waggons, of which "/, is usable. With regard to the necessary quantity of ice I refer to the printed statistics. Henri Chevalier (France): In certain cases the arrangement of the ice at the ends of the cars would be of advantage, although, theoretically, the arrangement under the roof is the best. For the transport of fresh cheeses from Normandy to Paris I have constructed cars according to the first arrangement and thereby rendered the loading of the ice and of the cheese very simple. Georges Villain (France): Under what conditions and terms are the special refrigeration cars placed at disposal? Prof. de Golovnine (Russia): Regarding this question, too, I point out that these data are contained in my publication. Chairman: As no one else desires to speak I thank the lecturer for replying to the many questions. 2* Sitting, 7” October, 1910. The Sitting began at 10 a. m. and ended at 1 p. m. Honorary President: Inspektor Georg Larsen (Denmark); President: k. k. Regierungsrat Gerst n e r (Austria); Vice-President: k. k. Kommerzial- 67% 1060 rat Josef Brom ovsky (Austria); Secretary: Hugo Tsch me 1 it sch, k. k. Oberkommissãr der Staatsbahnen (Austria). The Chairman Ing. Georg Larsen: I call on His Excellency v. We n dric h. General Alfred v. Wendrich (Russia) gives a résumé of his paper on statistics of refrigeration transport, and the appendix to this paper "The feeding of the nations.<. (St at is tique des transports frig or i- fiquess [see p. 937 and • A liment a tions des n a ti on sº [see p. 523). After the reading of an extract from the appendix to the paper, in the German language, by the Secretary, the discussion was opened. Mr. Henri Chevalier (France): I am in favour of the proposal of His Excellency v. We n d r ic h; the control is so much the more necessary because, thanks to cold, we shall from day to day be able to forward more valuable and more perishable goods to greater and greater distances, and delays will bring more serious consequences with them, so that producers and forwarding agents are equally interested in the avoidance of such delays. The high rates of interest on the capital spent for the refrigeration plants also require that the best possible use be made of the plant, and to this end this control will serve. Exc. v. Wendrich (Russia): In yesterday's meeting of the Russian Committee of Refrigeration my project, the accompanying note, was dis- cussed, and the representatives of Russia expressed the opinion that this control should be introduced not only for special cars but for all cars that convey perishable goods. Oberregierungsrat Grunow (Germany): As I have unfortunately not yet been able to subject the interesting statements of His Excellency v. We n drich to close tests as to their possibility of application on the Prussian state railways, I can only deal with one side of the question to-day. The accompanying notes, according to to-day's report, are also intended to serve the disposal of the cars and the superintendence of the running. Now against that l will point out the following. The cars destined for the con- veyance of easily perishable goods are, on the German railways, either, when supplied by private people and of special kind, provided with a mark of the station (stationed), or they are free cars; the latter is the case with most of these cars. The stationed cars must return, after the unloading, to the marked station, the 2 home station <; the owner of the private car has always the right to dispose of it. The free cars, on the other hand, must be telegraphically notified to the car distributing office on arrival, and on the same day this office disposes of these cars telegraphically. Under these circumstances it seems to me that the accompanying notes would hardly be able to be made use of for the purpose of distribution of the cars without seriously delaying the running of the car. K. k. Regierungsrat Gerstner (Austria): The lecturer has already mentioned that these accompanying notes are intended not for the directing 1061 of the car but more for evidence of the car as an aid for senders and receivers for the prevention of delays. Exc. v. Wendrich (Russia): It was stated that the accompanying note was a document for the distribution of the car; it has nothing to do with this, but if one desires to forward perishable goods rapidly one must introduce the automatic return of the car. S. Sklewitzky (Russia): I should like to consider the paper of Excellenz v. We n drich in comparison with that on to-day’s programme of Engineer Bloch. In the latter it is stated that the special treatment of easily perishable food is hardly to be considered as the direct task of the railway. Engineer B 1 och puts forward the demand that special societies shall devote themselves to the management of such transport, naturally not without payment. In order, however, that these societies may be able to calculate correctly, there must be statistics at their disposal from which it could be seen from where, to where and in what manner these transports take place. Mr. Ripert (France): It is absolutely necessary to know the paper by Engineer Bloch before the Congress of Refrigeration draws up the programme for the statistical committee, whose formation within the Asso- ciation Internationale du Froid is urged. Georges Villain (France) agrees with the proposal. Exc. v. Wendrich (Russia): I must explain that I have read the paper of Engineer, Bloch very exactly; his proposal has nothing to do with mine. My proposal refers to statistical control, more rapid running of cars, etc.; Engineer B 1 och, on the other hand, recommends that private Societies be chiefly called upon for the carrying out of the transport. Sektionsrat Dr. Deschka (Austria): I will only make the remark, from the stand-point of the Austrian Ministry of Railways, that the executive Organs on the railways are already very heavily loaded with statistical work, So that a further load would hardly be possible ; they are obliged to write Out numerous data not only on account of purely railway statistics but also on the basis of certain legal regulations, for example, for the excise. So great an additional load would necessitate a considerable increase in the number of employées. I must protect myself against the danger that the Statistical, or evidence work which would be connected with the new intro- duction of the accompanying note, may lead to a sensible increase in the work to be done by our clerks. Exc. v. Wendrich (Russia): The work with the accompanying note will not be too great, for the clerk at the despatching station does but enter his station, the sort and weight of the goods, and the times of depar- ture and arrival of the cars, nothing else. Gentlemen, you forget the pur- pose that every means of transport must be made possible. In other coun- tries, for example, in England, the cumbersome method hitherto followed has been abandoned. If you introduce this method of control the enterings 1062 of the stations customary at present can be greatly reduced so that even a saving will be effected. - - J. I. Silva-Freire (Brazil): I must point out, and the paper of Engineer Bloch confirms it, other conditions rule in Europe than those which rule in America, but in part also others than those in Russia, where very great distances are traversed without the car leaving Russian territory. The difficulty is in Europe, as Engineer B 1 och correctly remarks, in the littleness of the separated districts of management, and he expresses the desire that an international society may succeed in instituting general reform here and obtaining similar regulations for whole countries, in a manner similar to that which the Sleeping Car Company succeeded in effecting for express trains. The state railway engineers A. T. Will a me (Belgium) and E. T. St riem e er's ch (Belgium) as also Direktor V i 11 a in (Paris) propose the postponement of the discussion of the paper by Engineer B 1 och until Monday 10th October. - Exc. v. Wendrich (Russia): I should like to know if the meeting Corsiders the creation of a statistical committee by the Association Inter- nationale in Paris to be practical and necessary. (Agreement.) Secretary General J. de Loverdo and Direktor Villain (both France) propose that the proposal of the lecturer be sent before the General Meeting and base the proposal. ^ K. k. Regierungsrat Gerstner (Austria): I resume that Direktor Villa in and his colleagues have pointed out the difficulties in the way of such statistics, especially from the international stand-point. The matter was also put before the Bern Congress at which it was pointed out that the matter was not yet fully ripe for discussion and not so built up in all details that it was possible to determine already the requirements necessary for such statistics. I think it is, therefore, only necessary to propose to the General Meeting to agree in principle to the creation of such a comittee at the seat of the international Society of Refrigeration, and to give the directions which arise from to-day's debate. (Agreement.) The Secretary reads the paper by Oberinspektor Ho 1 it s ch (Austria) on xB e er tran s p or t on rail w a y sk. (See p. 1044.) K. k. Regierungsrat Gerstner (Austria) after repeating the paper in brief in French and English: I think it is not necessary to open a discussion on this matter, as the paper is more or less a historical review. (Agreement.) Chiefengenieer P. Fleury (France) speaks on 2M a in ten a n c e of the c o O 1 in g in cold tra n s p or t by a i r dry in g by me a n s of a new cool in g system «. (See p. 975.) The lecturer explains with the aid of a chalk sketch the construction of the car and the arrangement of the ice inside it. In reply to an enquiry by Prof. de Golov n in e the lecturer states that the load of ice is 1500 kilos per car. 1063 Louis. Robert (France): I think, in disagreement to the opinion of the lecturer, that for the transport of fruit and the first productions of spring which irradiate very much warmth the cold wagon of itself alone does not suffice, because the inner temperature of the car rises during the transport; thus, for example, strawberries have risen in temperature from 9° to 25°. It is thus necessary to subject field and garden fruit to previous cooling in a depot which is situated near to a railway and with which it has railway connection. For this reason cold storages have been erected in France in Condrien and in Châteaurenard and for this reason it is intended to build such in the chief centres of production especially in the Riviera from Hyères to Mentone - K. k. Regierungsrat Gerstner (Austria): The question has been put wheter meat and fish are also transported in this manner; the lecturer replied that fruit (apricots and other kinds) and flowers are transported. Fruit, in consequence of its absorption of heat from the sun during many weeks and its closeness to the earth, has an initial warmth which it trans- fers to the surrounding air. The lecturer replies respecting this that the high temperature of the stored goods has only the effect that the circu- lation of the air becomes greater and the cooling off of the air takes place more slowly, while the consumption of ice becomes greater. Further the question has been put by the flower cultivators and fruit transporters whether it is not quite superfluous to erect large ice depots and cold stores if it is possible without these to keep fruit undamaged even to higher temperatures, to 20%. The reply of the lecturer runs thus that the enemy to the preservation of fruit is not the heat but the dampness, and by withdrawing this from the air it is possible, even at somewhat higher temperatures, to preserve the fruit in perfect condition. That dampness, on the other hand, is dangerous, which arises naturally in the application of low temperatures with free transported goods. Fabriksbesitzer S. J. Benetter (Norway): How low was the tem- perature and what do you do in the transport of fish that require, indeed, a temperature below zero? K. k. Regierungsraf Gerstner (Austria): The temperature falls only as far as 1/2"; the lecturer himself says that his system is not suited to the transport of fish. Fabriksbesitzer J. Bennetter (Norway): We have to procure a car that combines the advantages of the ice car with the automatic car. All very low temperatures require expensive apparatuses and these are generally connected with the danger of fire. The question is how can one attain low temperatures with ice. In Paris I had the pleasure to report on the first experiments conducted three years ago in Norway. The temperature was then brought down and kept down to —5°. The experiments were instituted by the government on account of the fish transport. A mixture of salt and ice was made. The brine, which had a temperature of down to 15% below 1064 **, Zero, was sucked and returned by means of the pipes situated under the roof. An automatic regulator was set at a definite temperature, for instance from – 1" to 0", or from – 1° to + 1". The Norwegian and Swedish Government bought cars, and fish were sent with the best results from Drondtheim to Berlin, that is a transport of between 5 and 6 days. Lauritz Nilsson (Sweden) gives a résumé of his paper on Cooling in r a il w a y car sº. (See p. 979) The experiments of the Norwegian state railways, concerning which Mr. Ben n e t t er reported have, since then, been successfully continued by the Swedish state railways with two cars fitted out according to the newest system, in comparison to the cold cars, fitted out according to the former system of the Danish railways, and to a so-called American car with stove cooling, and that in the summer of this year, too. Among other trials one cool wagon made several journeys with meat not previously cooled, from south Sweden to the north east of Norway, a journey of 1600 to 1800 kilo- metres, about four days. The meat always arrived in good condition and with a temperature of from 2 to 3 degrees warmth. The Swedish state railways have bought a number of such cars together with the patents. Finally I will mention that well arranged cold storage at the place of production is of as much importance for these products as well built cars. As this cooling system was in work with the best results for three years the experimental Stage may well be looked upon as ended. It was shown that the cooling with ice and Salt is the simplest and admits of the most varied application. * Louis Robert (France). In France the experience was made that before the bringing in of the goods, especially of fruit, if it is desired to keep it fresh during six or seven or indeed only for four days, during the jour- ney a previous cooling is necessary; but Mr. Nils son says that in the newest Swedish cars which work with Salt and ice this previous cooling is not necessary Direktor Fischer (Austria): That the previous cooling does not take place in the wagon but in the cold storage is done in order to save ice, that is in order to suffice with less cooling material in the car. That there exists a car in which, with ice cooling that is reduced by salt solution, one can save the previous cooling even in the case of fruit, which rises in temperature during transport from 5° to about 25", is very satisfactory; in the case of meat, however, the previous cooling is necessary because the heat that must be extracted from it is so great that the quantity of ice conveyed would not suffice, for by lowering the temperature we do not save heat or cold, but we work energetically. Fabriksbesitzer Bennetter (Norway): We experimented throughout a whole year trying to load meat without previous cooling; in the case of fish, which are brought in from the sea in thousands of tons and must be 1065 immediately forwarded, the heat contained in the fish can only be extracted in the car. . Direktor Fischer (Austria): When I must go below 0° without previous cooling and have large quantities of fish to transport, the cooling in the car will certainly be more expensive than in the cold store. Fabriksbesitzer Bennetter (Norway): The meat must not be brought below 0°, a temperature of from 5 to 7 degrees suffices; there are also countries where the previous cooling cannot be undertaken; in Scandinavia for instance, we have no such establishments. 3* Sitting, 8* October, 1910. The Sitting began at 10 a. m. and ended at 1 p. m. * Honorary Prnsident: J. I. Silva - Fre i r e, Chief engineer of the Brazilian state railways (Brazil); President: k. k. Regierungsrat Gerst n e r (Austria); Vice-President: k. k. Kommerzialrat Josef B rom ovsky (Austria); Secretary: Hugo Tsch me 1 it sch, k. k. Oberkommissãr der Staatsbahnen (Austria). * The paper by S. J. Dennis on 2P re-co o 1 in g o f fruit in the United St a t e s of Americ as (see p. 464) is read for the author by Al. Gardner Vo or he es, and repeated in brief in French by the Chairman and in German by Regierungsrat Gers t n e r. There is no discussion. Harrold B. Wood (United States of America) then gives his paper on * Mech a nic a 1 p r o v i si on of cold S to re's a n d refriger a ti on c a r s with ic ex. (See p. 1033). The Chairman gives a résumé in French; there is no discussion. Mc. Pike (United States of America) gives his paper on 2 T he tr a n s p or t of easily per i s h a b l e g o O d S in America. Present cus to m. Prop os als. « (See p. 1003). The Chairman J. I. Silva-Freire (Brazil) gives a résumé in French: a German extract is given by Regierungsrat Gerstner, and he continues; Mr. M c Pike has drawn up several general resolutions which he recom- mends for submission to the General Meeting; these run : 1. It is desirable that special tariffs be fixed and charged for delays of perishable goods forwarded in refrigeration cars, if the receiver unduly delays the unloading of the car, for the prevention of unnecessary waiting of the car, and to get it as quickly as possible to its destination. 2. It is desirable that for almost all perishable goods the tariffs for refrigeration be reckoned not according to the quantity of ice but according to the distance. 3. As in most cases the senders of easily perishable goods know the state of ripeness of their goods best, the railways have the right to demand 1066 from the senders precise instructions regarding cooling, non-cooling or airing during transport. * * 4. As nearly all perishable goods, at certain times of the year, can be transported in ordinary goods wagons without harm, it is -desirable that the tariffs for such transport be the usual ones and that tariffs for cooling and other similar work be reckoned as extras. - Oberregierungsrat Grunow (Germany): The proposal desires to effect a uniform regulating of the questions touched upon for the whole district of the lands represented at the Congress. The conditions of traffic and tariffs are, however, very different in these countries. As regards the 1* point the keeping of the cars with refrigerating apparatuses is left to the persons who use the traffic, and these dispose freely of the cars. The levying of a high stand tariff is therefore so much the less possible, for in Germany in the case of delay in dealing with private cars, in part a reduced tariff, on private lines no tariff at all, is charged. With regard to point 2 it may be remarked that according to the German railway goods tariff the ice sent with perishable goods is generally sent free of tariff Point 3 finally, has no object in Germany because a difference between the tariffs for freight in cool wagons and in ordinary wagons is not made. The fulfilment of the proposals would under these circumstances render the liberally arranged German tariffs more unfavourable for the people engaged in traffic. I would therefore beg that the Commission move Mr. Mc Pike to withdraw his proposals. Prof. v. Golovnine (Russia): I am also of the opinion that the time has not yet arrived for formulating such proposals in so general a manner. Mc Pike (United States of America): I have only to add that in this case I have acted on a special injunction of the Society of American Railways. Chairman: Gentlemen, I beg you with regard to these important proposals concerning the entire future arrangement of refrigeration cars to make use of that institution which already exists, namely the Transport Commission of the International Societies of Refrigeration formed in Paris and to submit to this the proposals as material and basis for further study and the pursuance of this matter. (General agreement.) * Inspector Georg Larsen (Denmark) gives his paper on > A ft er- fill in g o f ice during transports. (See p. 1042) The speaker after finishing his paper puts the following proposal in French: As Cool cars cannot take up enough ice for the transport between distant places, for instance, from Denmark to Italy, there must be a mid- way station for the after-filling with ice, such as already exists in Russia and America. Hitherto it has been a matter of chance whether the car receives the necessary quantity of ice during its journey or not as arran- gements exist between the different railways regarding this matter. This forms a great hindrance to the extension of international refrigeration transport. I therefore propose that the II* International Congress of Refrigeration 1067 direct the attention of the managements of the railways to the neces- sity for an agreement regarding the after-filling with ice in refrigeration wagons during the journey”. Schmid (Russia): It would be very nice if an agreement was effected. I fear, however, that it would not be so easy to settle how much ice should be made ready for after-filling. For the internal traffic the quantity of ice necessary may be calculated from the statistics of the previous year; for the import and export, however, the possibility of prohibition in case of epidemics etc., would have to be reckoned with. In spite of this I suggest that the proposal of Engineer Larsen be accepted. Mc Pike (United States of America): In the United States difficulties arose with regard to the ice stores through the various conditions of the separate states; only with the combination of the railway commissions which brought these conditions under one concern did these matters improve Prof. v. Golovnine (Russia): I consider the resolution especially favourable to Russia, for this country can take easily perishable goods to all the harbours of Europe but not into the inland. Chairman: Are the Gentlemen in agreement with the proposal of Engineer L a r se n ° (Agreement.) It is accepted. An extract is then read from the paper by Ing. Richard Ste t e feld, (Germany) on 2 Col d tra n sport on r a i I way sº. (See p. 1018.) There is no discussion. 4* Sitting, Io" October, 1910. The Sitting began at 9.45 a. m. and ended at 12:45 p. m. President: k. k. Regierungsrat Gerst n e r (Austria); Vice-President: k. k. Kommerzialrat Josef B rom ovsky (Austria); Secretary: Hugo T's c h m el its c h, k. k. Oberkommissãr der Staatsbahnen (Austria). The Chairman k. k. Regierungsrat Gerstner: On the programme of the day we have a paper by R. van I ter's on (Amsterdam) on >R e fri- ge r a ti on car sº. (See p. 1052.) In consequence of a miss-sending the paper is not to hand, nor is the writer present. We thus come to the paper by M. Richard Bloch, Chief Engineer of the Orléans Railway in Paris, on "The present a r range m ent of refriger a ti on C a r S on the various r a il way s of Europe. The n e c e s sity of a un i for m regulation, D o cu m ent s, St a t is tic sº. (See p. 945.) The paper is printed in French and in English so that it is not necessary to read it. - Georges Villain (France) gives an extract and explains that Engineer Bloch takes up the stand-point that it would be better if those interested would combine for the provision of refrigeration cars, and by this means 1068 the railways would achieve a simplification and cheapening of the tariffs. Regarding the passage of the cars from Russia to France Engineer Bloch recommends that suitable measures be instituted. The Chairmann repeats these statements shortly in English and German. Oberregierungsrat Grunow (Germany): Gentlemen, I should like to explain that we are very much in sympathy with the statements of the reader of the paper, and I recommend the Commission to accept the resolutions; in the paper before us it is true these are not so clearly set forth as when Engineer * Bloch had the kindness to draw them up at a meeting of the Vth Com- mission of the International Societies of Refrigeration, in Paris on the 21* July. They were in Paris also accepted in the following form: , If on the one hand in the states with extended districts, for example, The United States of North America and in Russia (with Siberia), cars with airing, coo- ling or heating arrangements are successfully made use of, then the con- ditions in the states with smaller districts, as for instance nearly everywhere in Europe, are very different. For transport in the inner parts of the latter States the use of these perfected means on account of the shortness of the distances and the time of transport is, it is true, to be recommended, but it is not absolutely necessary. It is desirable that the managements of the European Railways make common regulations for the international traffic through which the sendings in refrigeration cars be all carried out with the assistance arranged according to the requirements of the traffic. Further it is probable that, in consequence of very varied steps taken by way of pro- vision which these transports require throughout their whole transit and in Consequence of the taking part of numerous companies, the provision of refrigeration cars at least in international traffic results better through pri- vate enterprise which must come to arrangements with the various rail- ways to this ends. Gentlemen, That is also the opinion of the Prussian state railways and of the other German railways. We have determined by way of tariffs that private persons may demand the provision of cars for certain objects; to these objects belong before all others perishable goods. The manage- ments consider it to be advisable for the wholesale traffic not to provide such cars themselves but to leave the keeping of these to private industry and by favourable conditions and contracts to assist the provision. Only for the piece goods traffic do we place in certain stations cars for butter, milk and meat. I come to some critical remarks. The figures on page 7 of the paper are not correct; there are not on hand 113 railway cars and 114 provided by private persons, but we have 217 railway cars and 1479 private cars; the figures referring to the other companies are also too low: By the German regulations the development is in no way hindered; that the num- ber of refrigeration cars in comparison with that for North America is far behind is explained by the different distances and climatic conditions. For the milk traffic, which mostly takes place in the early hours at cooler tem- 1069 perature, the provision of refrigeration cars is also not desired for this reason, because the milk begins transport uncooled. To leave the provision of refrigeration cars to those engaged in the traffic we consider to be correct, because here it is a matter of many individual peculiarities which state working cannot to such an extent Satisfy. That, as stands on page 12 of the paper, by providing our own cars at slight rates private persons are frightened out of providing cars is not correct so far as Germany is concerned. Further it is recommended in the paper to permit the car providers to pay rent; that Surely appears very risky. The provision of the private car is in Germany not altogether agree- able to the railways; we look upon it as a favour that we give to the private industry; to pay for it would indeed be impossible. That the companies in Germany do not consider many private cars of great value is explained by the fact that the transport of these cars when completely empty takes place free of charge. Finally the paper culminates in the wish that by mutual arrangements between the railway companies, the traffic from Russia may be furthered. The Prussian State railways will always be ready to make such arrangements, and I should especially like to put it into the hearts of the honoured representatives of Russia to give their attention to the traffic with exchange wagons. The Russian railways are it is true in this respect in a difficult position, because the exchange wagons provided as experiment chiefly run from Germany loaded to Poland; the sendings from Russia on the other hand come from far distant districts, so that the cars must be run empty to distant stations; in particular does this appear against the provision of private cars which was instigated by Ger- many two years ago. Perhaps on the basis of the points mentioned in this paper this question might be somewhat furthered. (Cheers.) (These statements were repeated shortly by the Chairman in French and English.) - Georges Villain (Paris) in French: Engineer B 1 och deals in his paper chiefly with two great questions: with the internal and external regulation and with the formation of great international Societies which have to render the transport in large districts more easy. Now in my opinion with the position of the question to-day, when it is not yet quite certain whether cold transport is absolutely necessary for all food materials and easily peri- shable goods and whether the previous cooling of certain products on short transports is not destined to play an important rôle, so that cold transport will only be absolutely necessary for very long distances and for very easily perishable goods, it is impossible that a meeting like to-day’s can form a resolution on the matter. I think therefore that this question is to be deci- ded by a commission that resides in Paris, if only for the reason that the regulations which would have to rule for the carrying out of such transports could be the same neither for the separate districts nor for the whole country, and the question therefore requires special study. 1070 So far, finally, as the resolutions are concerned that an international society should have to deal with the management of the transport of such products the position of affairs will probably not be so simple that it could be decided whether such a society could pay. The question whether this transport should be given to individual forwarding agents or to an inter- national society would therefore be probably also best solved by the same Commission. (Translated into English by the Chairman.) º: Prof. V. Golovnine (Russia): Whether such transport would be more or less favoured depends less upon technical than upon commercial grounds. Out of 2848 refrigeration cars which run in Russia the greatest number are destined for the conveyance of Siberian butter. It would be welcomed with great pleasure in Russia if a society formed itself which, through its relations with consumers and producers, made this transport of special size and importance. Schmid (Russia): The proposals of Engineer B 1 och and the repre- sentatives of the Russian government would be warmly welcomed if applied to Russian railways. • Where our goods are received at any time, if they arrive, we have arranged a certain traffic. These connections however could not live, and development could not go on if our unreliable sanitary measures had to be taken into account. It is my opinion, to speak according to the definite wish, that the International Society in Paris might also deal with the proposals for the arrangement of uniform sanitary measures such as, for instance, already exist in America, So far as the cars without direct unloading and reloading arc Con- cerned their provision is only a matter of time; if through the international regulating of sanitary measures or by definite laws the commercial ways were ensured, so that with full security it might be reckoned upon them change wagons would also be arranged: the great distances would not deter us is in this. Staatsrat Ing. Sklewitsky (Russia): The representative of the Prussian state railways expressed the opinion that the change wagon traffic was not , fostered by us; on the contrary I declare that the question of the provision of special cars by us has been favourably settled up to the point of mini- Sterial confirmation; matters are therefore not so hopeless in this direction. Exc. v. Wendrich (Russia): From the debate the necessity arises for the keeping of statistics regarding the direction, quantity and commercial relations, and I recommend the acceptation of the accompanying note; re- garding the international society proposed by Engineer Bloch I declare myself fully in agreement with the proposals. p Secretary General I. de Loverdo (France) takes note with thanks of the statements of the representative of the Prussian railways that his Govern- ment watch the endeavours of the refrigeration transport societies with good sº, 1071 wishes and readiness; he thanks Mr. Villain, who spoke in the name of the Ministry for Public Works respecting the still doubtful question, whether previous cooling or refrigeration cars. He discusses further the statements of Mr. v. Golov nine regarding the statement about the national organi- sation of refrigeration transport in Russia for import and export. * All these questions have indeed been already dealt with by the International Societies of Refrigeration in Paris, and indeed the experimental station in Châteaurenard is destined for the purpose of clearing up the questions raised by means of actual trials, as the following example will explain. Unfortunately owing to the shortness of fruit the experiment detailed in the following was only carried out on a small scale. , A case, insulated against the conduction of heat, was filled with over 500 kilos of fruit (grapes, peaches, aubergines, green beans and melons); this case was sent from Châteaurenard to Dijon, and from there sent back to the point of departure; after this transport of 52 hours the temperature had risen to 9°. (If the trial had been conducted upon a full wagon the temperature would have risen more.) The fruit arrived in absolutely good condition (Condensation of water vapour on the aubergines). The case was not ventilated. The test was conducted on such small dimensions only in order to illustrate the methodical and Scientific spirit which pervades the experiments in Châteaurenard. The experiments to be conducted are destined to discover the most favourable transport conditions for every easily peri- shable object. After continuation of the discussion on the papers of v. We n drich and Engineer Bloch the Chairman rises. Chairman: I think I can submit the following proposal: Mr. Villa in has worked out a final resolution in French ; Exc. v. We n drich is asked to state whether he is in agreement therewith. The resolution is read. (Agreement.) - The Secretary Hugo Tschmelitsch (Austria) reads the propositions in German namely: - > The Vth Commission of the II* International Congress of Refrigeration, after consideration of the papers by Exc. v. Wen drich and Ing. Bloch and after discussion of the resolutions according to the present position of the matter, leaves it to the managements of the separate countries to care for the drawing up of regulations and the legal arrangement of the applica- tion of refrigeration during transport according to the nature and manner of the trade, and recommends the following final resolution for acceptance: 1. A special committee is to be formed in the International Society of Refrigeration in Paris which shall have to study the question of inter- national refrigeration transport. 2. This committee will carry out the international regulation of transport. 1072 3. This committee will work out the practical measures which are necessary for the carrying out of the transit of the goods preserved by refrigeration.< Chairmann: The following amendment has been proposed: 1. The Congress expresses the desire that the transport commission which exists in the International Association of Refrigeration should devote itself especially to the questions of international refrigeration transport. 2. This Commission should also study the international legal transport regulations. The Chairmann points out that an international commission cannot well be entrusted with the study of laws and proposes other amendments, the following form being finally agreed to and read in the French and English languages: *The Congress expresses the desire that the Transport Commission, which is already comprised in the International Society of Refrigeration, shall occupy itself with the formulation of uniform regulations for cold transport both on land and also by water and that these endeavours may be effectually supported by the governments and railway managements. Further the Commission should occupy itself with the statistics of transport and suggest the pratical measures which are likely to render easier and to improve the carrying out of international refrigeration transports. COMMISSION VI. Legislation. 68 1075 General Report of Monsieur Maurice Quentin, Advocate at the Paris Court of Appeal, Doctor of Laws, Vice- President of the Administrative Commission of the International Association of Refrigeration and President of the Litigation and Arbitration office, in the Name of the Sixth Commission. • I have the honor to offer the apologies of our distinguished col- league, Mr. Raffalovich, president of the Legislative Section of the Inter- national Association of Refrigeration, detained by his duties in Paris, who was to present a general report on the work of our Commission. He entrusted to me, as vice-president, the duty of acquainting you broadly with our view as to our task at the Second International Congress of Refrigeration. Refore assuming the post of chairman, which has been kindly offered me by Mr. Huber, General Director of the International Field Sports and Shooting Exhibition, and President of this Commission, I beg permission to explain to you the aim of Our Section, If the object were simply to submit to you the various regulations concerning the use of cold and its application for industrial purposes in different countries this preamble would be superfluous: the interesting reports you are about to hear by experts would suffice. But it seems to us that our work would be incomplete if we did not first endeavour to determine the scientific basis on which it should rest. It is not enough to state that one nation has thought proper to adopt. a certain solution while its neighbour has decided to adopt another. The task of legislation consists, on the one hand, in studying the statutes and bye-laws of the different countries and, on the other, in comparing these various documents so as to discover the characteristic idea underlying them, in order to ascertain whether the respective governments have ini- tiated any new solutions or made improvements in those already adopted. 1. Following this rational method, we begin by assuming the principle that refrigeration, like, for instance the application of steam and electricity, is liable to the general laws of each country, but it is quite possible to conceive that, considering the services which this condition of nature may be expected to render to food, to hygiene, to manufactures, to agriculture, etc., they may form a subject for special legislation or particular regulations. 6S* 1076 We may easily anticipate a modification of the law against fraudulent practices, which tends to become general in all civilized countries, in order to cover the responsibility of a person who, having employed the normal means of preservation by cold, was misled by some defect in the machinery of which he was ignorant. It will be for each legislative body, to consider whether the deterioration of food stuffs or other products by increased temperature should not be exempt from penalty under common law by simply adopting the prudential measures recognized by science for preser- vation by refrigeration. 2. We consider, further, that in order to form a scientific conclusion as to the legislation applicable in the circumstances, the documents relating to the matter should be distributed, after a primary classification, in accor- dance with their applicability. The decisions of the public authorities may be divided into three classes : * On the one hand we must consider the general laws of the different countries interested in refrigeration as well as in other forces utilized by human industry. On the other hand we need to consider those laws which, although of a very general character, have a definite purpose as, for instance, the Argentine laws of 1877, 1887 and 1888, the object of which was to favour all enterprizes for the export of beef preserved by means not injurious to health. Finally, certain acts of an obligatory character have a special cause, as they result from the necessity of favouring the development of the science of refrigeration and as they relate, not to persons in general, but to certain persons on account of the services they may render. Here again we shall borrow our examples from the legislation of Argentina. 3. In grouping together all the documents that interest us we may assume another point of view, that of their constitutional origin. On one side we see the laws, properly so-called, emanating from the legislative power; on the other, the acts of the executive power, which acts include regulations issued for the execution of the laws, circulars for the purpose of instructing officials in the performance of their duties, and single acts concerning individuals, passed in execution of the legal statutes. 4. A new classification may be made according to the economic con- dition existing in the various countries. Countries are productive or con- suming or both according to their geographical situation. - You will remember the just observation of our General President, M. André Lebon, that the participation of the different countries in the Congress of Refrigeration did not involve renunciation on their part of the principles inherent in their political economy. Their legislation is dictated by their respective needs; and as these are not identical we must take this fact into consideration in the new classification we contemplate adopting. I have incorporated these various remarks in the two proposals I am about to read, and which I beg the Sixth Commission to adopt. 1077 I. & The Sixth Commission expresses the desire that the legislative work concerning the needs of refrigeration may be classified in three groups: 1* GROUP. According to their object: Statutes of a general character, special statutes of general appli- cation and particular statutes. 2nd GROUP. According to their origin: Statutes emanating from the legislative power; Statutes emanating from the executive power (administrative regu- lations, general or local — circulars to officials — acts applying to individuals). 3" GROUP. According to the economic condition of the countries concerned: - Statutes of producing countries; Statutes of consuming countries; Statutes of countries both producing and consuming. II. The Sixth Commission expresses the desire that the general and special legislation of countries in which refrigeration is used may be placed in harmony with the progress made in the science of refrigeration. In asking you to adopt these two proposals, and before taking the chair offered me by Mr. Huber, your official president, I avail myself of this opportunity to add the special thanks of our Sixth Commission to those of the Association as a whole for the kindness and courtesy of the Vienna Organizing Committee of the Second Congress of Refrigeration in allowing us to submit the reports which will now be read to you. 1078 Trade Laws and Regulations for Artificial Ice Manu- factories and Refrigerating Plants of Cold Storage Houses in Austria. By dipl. chem. Hans Tauss, k. k. Gewerbe-Oberinspektor, Wien I. Trade laws and regulations for artificial ice factories in Austria. In general the artificial ice industry, like all other industries in Austria, is subject to the trade regulations of 20 Decem. 1859, R.-G-Bl. No. 257, and of 15 March 1883, and 8 March 1885. These regulations determine the granting of industrial rights, the approval of factory premises and the contracts with industrial employées. Besides this artificial ice factories are subject to the law of 1895 concerning Sundays and holidays as rest days, the accident insurance laws of 1887, the reinsurance laws of 1888 against sickness, and finally to the respective provincial building regulations and certain special provisions for boilers, motors and other working ar- rangements. * Of these general regulations we will discuss those especially which are of greater importance for artificial ice factories. Further all special provisions, exceptions, extensions, diminutions of importance within the limits of above laws. * Of particular importance in the erection of artificial ice factories are all procedures and decrees of the authorities for the purpose of approval of the working premises according to § 25 of the law of 15 March 1883. In the provision of 14 December 1906, Z. 24.061, of the Ministry of Commerce general features for the carrying out of the preliminary steps, the com- missional hearing of the acceptance of the protocol, the decision of the authorities, the conditions to be demanded, and the manner of appeal are laid down. In the supplement to this provision there are instructions for the drawing up of projects of new or considerably extended industrial premises that require approval. - Of special importance to the projector are the conditions stipulated by the authorities in the documents of approval. These apply to the size of the premises, the working arrangements, especially as to whether and 1079 how many firing positions (boilers, etc.) shall be erected. These conditions are based, with regard to the building site, on the building regulations of the respective province, as regards the machine establishment and the buil- ding premises, in so far as concerns the protection of workers, on the regulations of $ 74 of the trade law of 1885, or the regulations of this office of 23 November 1905, and on special provisions concerning boilers, benzine-, Diesel motors (storage of benzine, motor oil), etc. As regards eventual electric plants the authorities usually take the conditions from the provisions of the electro-technical Society of Vienna for the year 1907. With regard to the circumstance that artificial ice factories, to be near their customers, are generally erected within the limits of large towns, the pro- visions also safeguard the neighbourhood against injury from smoke. Finally the documents of official approval usually contain provisions for the protection of customers. The most usual conditions are given in the following list: The boiler house must be built according to building regulations, and must, in particular, have only a light roof. The foundations especially those of the chimney must be laid as ap- proved by the official authorities, - The boiler furnaces must smoke as little as possible, good smoke-con- suming apparatuses being provided. Boiler waste water must be cooled before being let out into the public drains. - Good ventilation must be provided for in the boiler house and all rooms, windows properly fitted and ventilator pipes of sufficient size arranged leading above the roof. In rooms in which carbonic acid is kept or used the ventilation pipes, besides the openings near the ceiling, must also be provided with openings close to the floor, and all openings must be provided with fanlight shutters. Stables must also have sufficient ventilators, leading above the roof, and windows on the street must be fitted with safety locks requiring a special key. The floors of the stables and of the generator room must be water- proof, and the walls of the latter suitably protected against damp pene- tration. Any water taps in generator room or ice depot must be provided with safe siphon plugs. Ground level sittting and office rooms that have no cellars below them must also be protected against damp from the earth below. Court-yards must be drained and all W. Cs. and lavatories provided with water flushing arrangments. To certify the suitability of well water for the manufacture of ice for domestic trade a thorough chemical and bacteriological examination must be made at the expense of the applicant, and according to the results of such examination conditions may be imposed regarding the purifying of 1080 the water or the making use of other water. If the well water is found suitable and made use of, the well and its surroundings must be kept clean and no W. C. or drain may be laid within ten metres of it. An annual examination must be made to certify that the condition of the water is constant. The water gauge glasses of the boilers must be suitably protected. The maximum tension marks on the pressure gauges must be distinct. A fixed iron ladder must lead to the boiler platform. Between the boilers and the main steam conduits must be movable ladders, if possible with clamps. The dynamos and their conducting wires and the switch board must be protected according to the regulations of the Electro-technical Society. The transmission belts must be independent of one another and must be arranged so that they can be disconnected from the motor. All exposed moving machine parts, transmissions, straps, flywheels, etc., must be protected or enclosed to prevent accidents. Power machines must be provided with suitable protecting arran- gements and it must be possible Jor the workman from his station to stop them easily and safely. Belt bearings and rests must be provided; pro- jecting wedges or bolt heads must be either covered or removed. Steam engines must be provided with suitable starting and stopping arrangements. Carbonic acid containers and conduits must be made and kept as gas- tight as possible. Employees must be instructed how to act in case of sudden escapes of quantities of carbonic acid, and provision must be made that windows may be rapidly opened. The hands occupied in the generator room must be suitably protected (warm clothing, gloves, waterproof aprons) against the cold and wet; for all hands a dressing-room with washing arrangements, if possible, with a warm shower-bath, must be provided; and it is also desirable that an eating room be arranged. All hands must be free of infectious and skin diseases and of loath- some affections: they must be reminded that in case of infection at home they must not appear at the works until the sickness is past and the prescribed disinfecting measures have been carried out. When the premises are completed their approval must be applied for. Should an artificial ice factory be situated on a public railway line, the following conditions are also stipulated : The buildings must be fire proof and covered attic openings on the railway side must be either covered with glass or with a fine wire pro- tection; finally the railway company is not responsible for damage to the buildings or their contents, but such damage must be entirely borne by the owner of the bulding. 1081 Frequently for the protection of the neighbours the documents of approval contain provisions for further safeguards in case of well founded complaints regarding Smoke, unhealthy gases, etc. Customers are protected by regulations that all vessels for the ice or water must be such as can cause no harmful effects. This end is also served by the already mentioned conditions regulating the use of pure water and the exclusion of workers with infectious illnesses. Regarding professional assistants the regulations published in 1885 apply. As it is impossible for these factories to work at definite times, special provisions allow of exceptions to the regulations regarding hours of rest and daily work. With regard to the former, ministerial regulations of 7th May 1885 provide that during continuous work all hands shall have at least a half hour rest at mid-day. It is not necessary to fix definitely other intervals of rest. Hands not engaged in continuous work must be given the legal intervals of rest. - - Regarding regulations as to the daily maximum time of work of eleven hours, Department of Commerce, provision Nº. 85, allows a twelve hour period of work inclusive of rests, on work connected directly with continuous operation. It must be pointed out here that in the -hours of works regulations a variable employment of an individual worker, in the first place in machine working and in the Second place in cartage work, or vice versa, is only permissible if the total of the hours of work does not exceed eleven per day. Only in exceptional cases, on three days in a month, is a longer period up to fourteen hours permissible after previous notice has been given to the authorities. * Of special importance to artificial ice factories is the regulation of Sunday and holiday rest. Not only technical matters, but also the relation of purveyor to customer, and particularly the need of the latter to receive the normally necessary quantity of ice even on Sundays, must be here considered. Accordingly exceptional conditions are granted in favour of artificial ice factories, as compared with the severe regulations of the law regarding Sunday and holiday rest of 1895, Art. 1 and Art. 2, wherein a 24 hours Sunday rest is fixed. The Department of Commerce regulations on this subject of 24 April 1895, § 2, Articles 31, and 8 April 1904, R.-G-B1. Nr. 35, read as follows: Sunday work is allowed: a) for ice making from 12 m. to 6 PM; 6) for delivery of ice until 12 m. Compensatory rest: A worker employed more than 3 hours on Sunday must be given a 24 hours rest on the Sunday following. These concessions met with much opposition. They seemed too limited and insufficient particularly for the summer requirements of the patrons. On the other hand it was submitted that the artificial ice trade was a sort --- 1082 of season industry; that the demand for its product increased enormously in the hot summer months, and that both the forced cessation of work for six hours on Sundays, and the prohibition of deliveries after 12 o'clock m. causes many, inconveniencies not only to the purveyor but also to the customer and consequently also to the general public. On hot summer days it is often impossible, in inns, coffee-houses and restaurants to procure the necessary supplies of ice on Sunday morning for the preservation of meat and other perishable food, milk, beer, etc. It is declared to be necessary that in hot summer constant operation be maintained on Sundays. *- On the other hand it is maintained that in the cold season work may stop on Sundays entirely and that delivery could be completed in 3 hours in the morning without any disadvantages. In consideration of the fact that during the past winter the crop of natural ice in Vienna and the surrounding districts almost entirely failed, and that this summer the production of the therefore large amount of artificial ice was extremely difficult, permission was given, by Department of Commerce, regulation of 4 July 1910, to artificial ice factories to manu- facture during the whole of Sunday until 11 September inclusive. As regards compensatory rest, difficulties only arose with drivers and other outside employées. Each knows only a definite circie of customers, whose special requirements he knows as also the particular manner in which the ice is stored, in short all the conditions relating to the particular customer. Hence it is extremely difficult to find a suitable substitute and to suffi- ciently instruct him when found. On the other hand the customers them- selves are accustomed to certain delivery men, and have frequent occasion to complain if their orders are not correctly carried out by the substitute men. For the rest, so far as accident and sickness insurance of workmen is concerned, the general standards apply. In this matter it is only worthy of note that doubt arose as to whether the hands employed in the depots of the factories were eligible for insurance. For this last it must be said that these depots and everything appertaining to them are eligible for insurance, and that analogous organisations such as beer depots, even if worked with- out motors, are also eligible. Trade laws and regulations for the cold plants of store houses in Austria. In general the above laws and regulations apply also to refrigerating plants in store houses. Of special consent regulations we note the following: Store rooms for food must be kept quite separate from other store rooms for other objects, and the rooms used for the storage of food stuffs must not be used for storing other substances; the whole arrangement must be such that no contamination of food products is possible. 1083 The cooling and freezing rooms must be well ventilated. These rooms and all stalls or vessels for containing food products must be so constructed that they can be easily cleaned; for this purpose water cocks are to be provided in every room. As regards other regulations for such plants it is, further, worthy of smention that in some large towns special safety regulations for lifts are made. Of great importance here, too, are the the regulations of 24 April 1895 on Sunday rest which allow all work with refrigerators, motors and subsidiary machines to be carried on throughout Sunday. 1084 The Use of Refrigeration in Sweden. By A. de Berencreutz, Chamberlain of H. M. The King of Sweden, Paris. In Sweden, it has not been considered necessary to legislate on the subject of refrigeration. Nevertheless cold is much used in the preservation and transport of perishable food stuffs. It must be borne in mind that our thousands of lakes mostly with pure clear water supplying ice relatively pure have until recent times been sufficient for our needs in this respect. Every- where in the country near the farmhouses may be seen stores of ice, sawn into square blocks, and covered with sawdust. In the towns great depots of ice are kept in the breweries or at the ice-merchants; while in private houses ice-safes, with insulated compartments, are also in general use and are prominent objects in the kitchen or on the landing. Meanwhile mechanical refrigeration is advancing with us as well. With the development of trade and manufactures in the great towns there is an increase in the use of refrigerating appliances, I leave it to the engineers and specialists attending the Congress to describe the experiments and the progress made in this direction. And I refrain from discussing in this section the laws that obtain with us on the import and export of perishable food stuffs in order to prevent adulteration and ensure a supply of wholesome food to the people. More general interest attaches, I think, to the measures adopted by the Railway Companies for the transportation of perishables, such as butter, meat, etc., with the aid of refrigerating installations. * * For the transport in question there are cars of three different types running on the various lines. These types chiefly differ from one another in the manner of disposing the ice chambers. - The most pressing need at present is a refrigerating car in which the temperature can be reduced below that of the ordinary car. This type of car is especially required for the carriage of fish, and is now receiving the attention of the General Railway Direction. -- ~ The working of these refrigerator cars as well as the carriage of the perishable food itself, is shown in different plans issued by the General Direction. Particulars are also given of the lines on which these cars' run and of the connections with such lines. - $2. 1085 The State Railways have established ice depots in certain stations which are numbered in the plan for the carriage of butter for exportation. There are at present 44 of these depots. In summer the cars used for the carriage of butter will be supplied with the necessary quantity of ice. Before loading the temperature must not exceed 12 degree centigrade. If the temperature rises during the journey there must be a fresh supply of ice. The forwarder of the goods is responsible for the refrigeration, but it may be undertaken by the railway authorities. It is the duty of the offi- cials to see that butter entrusted to the care of the railways is kept cool. In certain stations where goods have to be transferred to another line cooling sheds have been erected for the storage of the butter. Other plans indicate the lines and the trains for the carriage of parcels and the express trains for the goods that concern us. These plans also refer to other articles of fresh food, such as: fresh and live fish conveyed in tanks, fruit, berries, fresh vegetables, oysters, lobsters etc. During the cold season our railways have also introduced wheated wagons.< for the carriage of goods liable to deterioration from low tempe- rature. In conclusion it is worthy of note that during the closed season the sale, purchase, delivery, and carriage of game from place to place is for- bidden unless proof is forthcoming that it was taken within the authorized time or otherwise acquired in accordance with the law. 1086 The Present Status of the Refrigerating * Industry in Russia. By Basil Elie Dennissoff, Equerry to His Majesty etc., St. Petersburgh. Representing the imperial Russian Government and as president of the Russian Committee of Refrigeration, I desire to offer a few remarks on the relative position occupied by Russia at present in refrigeration, with special reference to prospective development in view of the rapid progress of agriculture and manufactures in our country. The work presented by the Russian Committee under the title x The present position of refrigeration in Russia.< gives an exact statement of the matter and is supplemented by diagrams and tables of statistics. Many of you, especially those representing countries with a well-developed system of refrigeration, after studying this work may conclude that the results ob- tained in Russia are very small compared to the immense natural resources of that vast country. * & In fact the place occupied by Russia in the cold technics of the world must be considered a modest one if we look only at the number and size of her refrigerating establishments. But it must be remembered that we were relatively very late in entering the international market for perishable food stuffs. It is hardly ten years since Russia commenced to export in consider- able quantities her Siberian Butter; the export of eggs and poultry began much later, while the export of provisions remains to be organized. The example of countries possessing a more highly developed agri- cultural industry shows that refrigeration develops in proportion to the ex- port of perishable food stuffs. For countries unable to consume all the products of their agriculture the organisation of the export trade and of refrigeration become matters of vital importance. * In Russia we have not felt so keenly the necessity for organising this export of perishables, our country with its patriarchal and insufficiently developed, agricultural organisation being until quite recently in the markets of the world only the traditional purveyor of corn and flour. * 1087 But for some time, I may say: in the course of the last few years, a new era of progress and intensification has commenced for Russian agriculture. . . Various economic factors have contributed to this change, the chief being the great agrarian reform now going on and tending to substitute individual ownership by the farmers for the present system of agrarian Commission. It is impossible for me to state the extent to which this reform as well as the construction of trunk Railway lines and the rapid extension of education will contribute to promote trade in perishable food stuffs. . . . . Suffice it for me to say, that the intention is to create some tens of millions of homesteads, and you will understand that perhaps in ten years Russian commerce will require such a number of refrigerating plants as will make what are now in use appear insignificant. Judging by the importance of the export goods traffic on our lines the plant is insufficient, even for present requirements. In 1909 there were exported from our frontier 57 million Kilos of butter with a value of 131 million Franes, 3 milliard eggs worth about 7 million francs, 12 million Kilos of dead poultry and game valued at 14 million francs. -- In 1907 Russian railways carried: 130million Kilos of meat, 213 million Kilos of milk, 157 million Kilos of dead poultry and game, 612 million Kilos of vegetables, 376 million Kilos of beer, 765 million Kilos of fish, 341 million. Kilos of fruit. Total 2 milliard 720 million Kilos of perishable food stuffs. At the present time Russian capitalists are showing intense interest in the development of refrigeration for industrial purposes. The first international congress of refrigeration in Paris and the energetic action of the Russian committee of refrigeration gave impetus to the mo– vement which met with general public Sympathy and generous support on the part of the government. A number of big Companies are being formed in Russia for the purpose of establishing cold storage warehouses and for refrigerated transportation. The idea is growing and expanding daily. And in concluding my remarks I venture to express the conviction that the Congress of Vienna should not confine itself to contributing to the theo- retical and practical advancement of this new science of refrigeration, but should also attract to refrigeration the capital which hitherto in Russia as elsewhere has not shown the same interest in it as in the older branches of production. 1088 The Refrigeration Industry in the French and Other Colonies on the West Coast of Africa. By A. Gruvel, Professeur de Faculté; Chargé de Mission. The Refrigeration industry is, generally speaking, very little developed in the French and Foreign Colonies on the West Coast of Africa, which we have been permitted to visit on the Mission which Governor General Ponty has been good enough to entrust to us. Where this industry is found it consists in the production of a more or less considerable quantity of ice, often obtained by out of date apparatuses, producing it under unfavorable economical conditions. Even in certain hospitals ice is entirely wanting, while all Colonial Doctors know how valuable this product is as a therapeutic auxiliary in many illnesses so common in tropical regions. If in all the hot Colonies, ice could be delivered at a low price so as to be within the reach of all, alimentary hygiene would be improved in a proportion not suspected by those unacquainted with tropical climates, especially those near the equator. Up to the present, the small quantity of ice produced is indispensable, and often entirely insufficient for the cooling of beverages. Cool drinks in these countries are certainly very pleasant, but they are not absolutely in- dispensable, for one gets easily accustomed to the consumption of the diffe- rent beverages at the surrounding temperature. At any rate, this should be but a small part of the question, although up to the present it is generally the most important. - Cold Stores for the preservation of imported perishable food stuffs do not, it may be said, exist on the West Coast of Africa, as only one place is provided with them, viz: Lagos, an English Colony. There are several reasons for this: the first, and often the most important, is the still very insufficient acquaintance on the part of those engaged in the refrigerating industry with its different applications, and the benefits that may be derived therefrom if only the trouble is taken. Further, the centres of European population which are the only ones that could support a refrigerating plant, are of little importance, too far from the 1089 coast or from each other, or the means of communication between the different centres are too primitive to give any likelihood of developing the industry. The Elder Dempster Co. of Liverpool might be mentioned here, as it regularly carried food products for sale on the coast. All the steamers of this Company are provided with cold storage and sell at list prices excellent foodstuffs, which one is very fortunate to find in certain quarters of the dark continent. The day when all the Companies serving West Africa, follow the example of the Elder Dempster Co., refrigeration depots can be established on the coast and provide the Europeans who live all the year round almost exclusively on preserved food, with a hygienic food, the effect of which on the general sanitary condition of the colonies we are considering will no doubt be considerable. It is clear that only centres of a certain importance can benefit by such installations, but these are also the most interested, because they contain a considerable European population who are the only regular consumers of imported perishable foodstuffs. In the above we have included foreign colonies as well as our own French Colonies, for, as we shall see in the following, it is not always the French Colonies that are worst off in this respect. t Let us therefore examine the actual condition of the Refrigerating In- dustry in most of the French and other colonies, on the West Coast of Africa. SENEGAL. We have already shown elsewhere") all the benefit that would accrue to Senegal from the installation of Refrigerating Depots and a regular service, as well in the import of perishable foodstuffs as in the export of certain colonial products, as for instance: beef, fish, fruit etc., to Europe, which we push but little in this colony. It may be said that all the ice manufactured in Senegal, and parti- cularly in Dakar (Private Industry and the Dakar-Saint-Louis Rºy), in Saint Louis, in Thiès, in Fatik etc., is exlusively for the purpose of cooling beve- rages, either for hotels and cafés which are large consumers, or for private consumers. Some dealers use the ice for the preservation of certain food- Stuffs, such as early vegetables, hams, Sausages etc. Perhaps Dakar will have before long an ice factory that will be able to supply ice under entirely suitable conditions, for it is becoming an im- portant provisioning centre for the large Steamers that call there. & Finally, there exist in many of the Senegal offices small ice machines on the Carré system which indeed are of great service to Europeans, scattered in the bush, especially at the time of the arachide trading. But in the hands of native attendants these frail machines are quickly destroyed. 1) See A. Gruvel: The Refrigerating Industry as a means of developing some French Colonies (International Congress of Refrigeration, Paris, October 1908). French West Africa and the Refrigerating Industry (Congress of Sea-Fishing). Les Sables d'Olonne, September 1909. 69 1090 BRITISH GAMBIA. There seems to be only one small ice machine at St. Mary, Bathurst; its small output is entirely used for cooling beverages. Bathurst is not of enough importance to admit of a more costly installation. PORTUGUESE GUINEA. When I passed through Portuguese Guinea in 1907, there did not exist in the principal centres of this colony; Cacheo, Bissao and Bolama, a single ice machine. I do not think that, in this respect, matters have improved much since then. FRENCH GUINEA. At Conakry it is the principal hotel in the town that manufactures ice for its own consumption and for private people to- whom it is sold at 50 centimes per kilo. The Ammonia machine used can make about 500 kilos per day. Almost the whole output is used for cooling drinks, and only a small portion goes into, the ice boxes of the restaurantS. The butchers being all natives never use the ice for the preservation of meat, or minced meat. Conakry is one of the centres on the African coast which would most quickly benefit by cold stores and refrigerated transport to the Metropolis, for the district is destined to become a very important centre of production of bananas and pineapples. Already a great deal of this fruit is shipped to Europe in ordinary steamers, but when this can be done in refrigerated . holds, at a constant temperature, the production will rapidly increase. From time to time, but I believe in an irregular way, a certain quan- tity of ice is sent by rail from Conakry on the Niger (K. N.) to one of the most important centres on the line, namely Kindia. SIERRA LEONE. At Free-Town there was established a Company for manufacturing ice and aerated water, which had also built a cold store for keeping the principal perishable foodstuffs, and especially for meat from Europe. This undertaking did not meet with the success which it deserved. IVORY COAST. The Refrigerating Industry is very primitively repre- sented in this colony. There is, at Grand-Bassam, a small machine which can supply Scarcely 120 kilos of ice per day. The output is used only for beverages, and on certain days for the preservation of perishable foodstuffs, such as butter, cheese etc., which are procured from the steamers that call at this place. At Bingerville there is also a small ice machine for the supply of the public works of the colony. Finally at Abidjan, there is another owned by the Railway. This is not much, as may be seen. w GOLD COAST. The British Gold Coast seems to us to be still worse provided than the Ivory Coast. The two places where we have stopped: Accra and Addah, do not seem to possess any real apparatus for making ice. There are perhaps some small private hand machines, but no factory worthy of the name. -º-, 1091 DAHOMEY. Our Dahomey is not quite as badly provided, but the industry is there reduced to its simplest form. The only hotel in Porto-Novo has a small machine, which, if every- thing goes right, which is seldom the case, produces about 300 kilos of ice per day. The proprietor receives from the Local Government a monthly subsidy, for which he is obliged to make a fixed quantity of ice, a part of which is sent to Kotonou. As is the case everywhere else the whole output, often quite insufficient, is used for cooling beverages, and for pre- serving, in ice boxes, certain foodstuffs such as butter and cheese. NIGERIA. At Lagos we find the first ice factory of importance in connection with a cold storage for preserving perishable foodstuffs. The ice factory is installed in the Public Works Building of the Colony. We were permited to visit it under the escort of the Naval Lieutenant who manages it in the name of the Local Government. The machine, of the Linde make, working with ammonia, can produce about 5000 kilo of ice per day. It cools a room separated from the factory, but perfectly insulated, and divided into three compartments. The smallest is for frozen salmon and other fish from Europe; the medium size one having an average temperature of only 12°C. is used for preserving fruit, and the third the largest of the three is for chilled meat. The Local Government which owns the factory and the cold store makes and sells the ice, and stores under certain conditions the foodstuffs brought in every week by the Elder Dempster boats, the only users of the cold store. This is therefore not open to the public, but the latter can provide themselves from its store by communicating with the Elder Dempster Agent assigned to this special duty. Almost all the ice made is consumed in the town itself, a small quantity being forwarded every day to Ibadan, to the residence, the hospital and doctor. This ice is almost exclusively used for the cooling of beverages, especially soda water which is consumed in considerable quantities. Some private people have ice boxes in their homes. The price of ice is 10 centimes per kilo. The Elder Dempster Company has an ice machine on the Carré system at Calabar which can make nearly 500 kilos per day. A part of this is sold to private people, while the rest is used to ensure the preservation of the foodstuffs brought in every week by the Company’s boats. Unlike the one at Lagos this factory does not cover its own expenses. There is also a factory under construction at Wari, and at different places some very Small apparatuses belonging to private people. CAMEROUN and SPANISH GUINEA. In German Cameroun and in Spanish Guinea there does not exist any refrigerating industry properly speaking, 69% 1092 GABON. The same can be said of our French Gabon. At Libre- ville, it is again the public works department which has charge of the ice making. There is an apparatus working on the Methyl Chloride system, which works fairly well considering its age. If this machine worked continuously it could produce about 500 kilos of ice per 24 hours. The blocks are placed in an ice house from which they are taken for sale to the officials and to the public at 50 centimes per kilo. Only the hospital is provided free. The only European butcher is also supplied regularly, but instead of paying cash, he has undertaken to slaughter a certain number of oxen per month. The monthly consumption of ice at Libreville, by the hospital and by private persons, is about 1500 kilos, which is almost exclusively used for cooling beverages. The public works own moreover a small auxiliary appa- ratus called * Frigorigène Audiffrenz of Epinal. This apparatus, well-known in the industry, will cool water to 4°C. by turning it 15 minutes, or in 25 minutes a layer of ice 1 cm thick will form on the rotating cylinder when it is required. This apparatus is chiefly intended to supply ice or iced water to the sick in hospital in case of stoppage of the larger machine. The manufacture of ice in Libreville does not bring much profit, to the Colony, but it covers expenses and allows the quantity necessary for the hospital to be supplied free. At Cape Lopez ice is not made and can only be bought on board the German and especially the English boats which stop there. The Elder Dempster boats of which we have already spoken sell all sorts of produce from the 2 West African Cold Storage Co. Ltd. at fixed prices not very high; there, as at all the Ports at which they call. In the whole interior of Gabon, ice is naturally a myth, and only those who have passed through there know with what infinite pleasure one occa- sionally drinks a cool beverage. BELGIAN CONGO. I am not considering the employment of refrigeration in the interior of the Belgian Congo where I have not been. At BOMA, the Government manufactures about 3000 kilos of ice per day, reserved for the use of officials only. A new machine was expected when I was there and the one then in use was to be sent to Banana, where there was no apparatus for the artificial production of cold. At MATADI, the Railway administration makes about 3000 kilos of ice daily for those of its staff living in the town and along the line. It is per- haps a somewhat onerous undertaking, but one on which the Company can only congratulate itself in view of the sanitary results obtained. Should there by any chance be any ice left over, it is sold to private individuals, ANGOLA. The capital of Portuguese Angola, Saô Paulo de Loanda, has two separate ice factories, installed in the Cafés of the town. One uses a Douane machine working with Methyl Chloride, and producing 1093 400 kilos in 8 to 9 hours daily. The ice is kept in a special box. It is used in the first place by the Café, and next by the numerous Europeans inhabiting the town, to whom it is sold for 100 reis, or 50 centimes per kilo. The water used for its manufactures is from Bengo, from the canals for suppling the town, and is first filtered. The second, installed in another Café, has a machine made by Grimaud, Lesoutaché and Félix. It works on the Ammonia system using 5 h. p. It also produces about 400 kilos ice per day, used in the same way, and sold at the same price. Saint Philippe de Benguella has also a small ice machine, but I know of no others for public use in the whole of Angola. SOUTH AFRICA. There is in Cape Town an important ice factory under the name of >The Imperial Cold Storage Supply Co. Ltd.<. This Company was started in 1897, at a time when a considerable amount of cattle plague was about, which made it necessary for the Colony to procure beef elsewhere. Recourse was then had to chilled meat from Australia and the Argentine, which was placed in the cold storage rooms built for this purpose. 1 visited this interesting establishment in all its departments at the time of my stay at Cape Town. It is a very prominent building situated on the quay, between the harbour and the town. Cold is produced by two steam engines, working alternately and driving refrigerating machines of the Hercules Ammonia type. One of these machines can make 70 tons, the other about 60 tons of ice in 24 hours. But the actual average output is not more than 60 tons per day. 3. This ice is used in the following manner; about 5 tons per day are delivered to the steam trawlers which fish on the Banks; a large quantity is used for the refrigeration of cars running on the various lines of the South African Railway for the transportation of meat, butter, fish, lobsters, vegetables, fruit, etc. The cars which originally belonged to the Refrigerating Company have been bought by the Railway Company. The insulation used in these cars is mineral wool, and at each end there is a reservoir for broken ice. Goods are sent thus to the Transvaal and up to Salisbury, in Central Rho- desia, where they arrive in perfect condition, after five days rapid journey and with only one additional charge of ice at Kimberley. Finally the rest of the daily output is used in the town itself or in its immediate neighbourhood, either for the ice boxes which all the butchers have, or for the cooling of beverages. In connection with the ice factory is a system of cold storage chambers, the total number of which is 16, representing a capacity of 160,000 Cu. ft. They can hold 31.500 quarters of beef, without counting fish, vegetables, fruit etc., at very different temperatures in the different chambers. 1094 Thus for instance ice and butter are kept at a temperature of 12° F, cured bacon at 16 or 18°F, apples at 35 to 36°F, bananas, coming from Natal to be ripened, at 60° F etc. This Company did an excellent business at the time of the Boer War. At the present time, however, it is far from giving similar results, although running in perfect order. The same Company has another factory at Woodstock, almost equally large. Therefore, thanks to the now important railways, and also to the excellent organization of the Refrigerating Company, all perishable foodstuffs coming from England or from the coast can be transported in perfect condition for considerable distances to the interior. It should be noted, also, that England sends considerable quantities of foodstuffs of all kinds by the magnificent boats of the Union Castle Line. Some is used for provisioning the coast, some is unloaded at Cape Town, put in cold storage and sent through the whole Colony. As will be seen from this paper the English Colonies, Nigeria, and Cape Colony, are the ones on the West and South Coasts of Africa where the Refrigerating Industry is of real importance, because by means thereof it is possible, first to make all the ice necessary for consumption, and secondly to store the imported foodstuffs when they arrive in the Colony, as well as the Colonial foodstuffs waiting to be exported. In conclusion we can not sufficiently urge manufacturers to devise a simple and practical machine for the Colonies. The Carré apparatus, which seems to be the most practical and the most used in the different Colonies that we have visited, gets easily out of order when carelessly worked, as is likely with almost all native attendants. The Audiffren apparatus, which I have only seen at Libreville, would seem to me much more useful if it was a little less bulky, and especially not quite so dear. If the manu- facturers can invent an apparatus, which does not take up much room, is strong, and can be sold at a reasonable price, I am certain they will be able to dispose of many. _* *. 1095 Data on the Soil, Climate, Ranches and Slaughter- houses in the Republic of Paraguay. By the Consul General Leo Hirsch. Climate. In regard to climate there must be distinguished three distinct zones in the Republic of Paraguay, viz. the tropical zone characterised by a mean temperature of more than 25°C., the subtropical zone and the temperate zone, the mean temperature of which varies from 15° to 209. 3. As regards temperature and seasons, the subtropical zone resembles the most southern parts of Europe and the north of Africa. The summer of this zone comprises the months of December to Fe- bruary, the winter, the months of July to August. The difference of tempe- rature is however of very little importance, and the intermediate seasons, spring and autumn, especially, can hardly be recognized in any part of the Republic of Paraguay by special characteristics. As regards the southern region, where the mean temperature of the winter and summer months hardly differs by 29 C., it is therefore scarcely possible to speak of seasons in the European sense. In the northern region winter is characterized, it is true, by low temperatures, and the phenomena of frost, which mostly pro- duces only sheets of ice as thin as paper on very small expanses of water, may be observed almost every year, but there never falls any snow. In the southern or tropical region however, where the thermometer rarely falls under a minimum of 15° C., and the mean temperature rises in general to about 25°C., the seasons are not characterized by warmth and cold, but only by the distribution of rain. It is hardly necessary to mention that the parts of the Republic of Paraguay comprised in the temperate zone possess an especially favourable climate. The climate may be considered indeed as the finest in the world. The mean temperature constantly shows 20° C. The winter, which lasts from June to August, is mild and conducive to the health of Europeans as well as of Americans. The wet season principally comprises the winter as well as part of the autumn, * t 1096 Nature of the soil. Paraguay is the country of the future, because the climate as well as the nature of the soil are so favourable that it is easy for an agriculturalist to produce in Paraguay from 7 to 8 times more than in Europe. Wherever the soil is tilled, the ground is even, and does not contain any stones, scrubs or trees. It is formed by large tracts of alluvial deposits comprising layers of black mould (humus) of varying thickness from 20 to 80 centimeters) and of great fertility. As soon as there has fallen a sufficient quantity of rain, one may break the fields, i. e. draw forthwith the first furrows, with a strong and simple plough. As already mentioned, there do not occur any snowfalls in Paraguay Vegetation does not cease in winter, and the cattle graze all the year round in the open air. They need neither be looked after, nor taken care of, neither fed, nor stabled. Ranching. Paraguay offers the very best conditions for cattle-breeding. Although the climate is different in different parts of the country, there are never- theless everywhere grazing-grounds — rich in vegetation — which offer excellent, pasture to the cattle. Still better results might however be obtained in this respect by the introduction and acclimatization of foreign fodder-plants. There are estancias (farms) from a legua (2500 hectares) to 10 and 20 leguas (25,000 to 50,000 hectares), and there are estancieros (farmers) who possess from a 1000 to 30,000 and 50,000 head of cattle and thousands of sheep. It is really a pity that the Austrian capital or the Austrian agri- cultural emigrants who are well-off do not avail themselves of these extremely favourable conditions. It is the duty of the Government as well as of the public and the Austrian shipping companies to call the attention of the peasants enigrating from Austria-Hungary to this agricultural el d or a do, as they would easily find there by family association an opportunity to acquire land and cattle, for even to-day farms yield very considerable net- proceeds in comparison with those obtainable in Europe. The number of cattle in Paraguay at the end of 1909 was estimated at 6,500.0000 head. The different varieties are the result of the crossing of Spanish-Portuguese and Dutch breeds. The results of recent cross breeds have besides been carefully studied for some years. In Paraguay the production of meat is considerably greater than home consumption. The competent authorities must therefore already now organize on a large scale the export of meat in form of meat extract, corned and frozen meat. - This fact clearly shows that the refrigerating industries are of the greatest importance for Paraguay. By means of cold the meat of Paraguay is supplied to the consumer under the most favourable conditions of con- 1097. servation and hygienics. The Political Economy of Paraguay will conse- quently have to consider as its principal object to interest European initia- tive in the constant increase of the stock of cattle of the country by. attracting attention to the following facts. •º Slaughter-houses. There exist in Paraguay factories for the manufacture of preserved meat either by the process of corning, drying, canning as well as extracting. Among these factories there must be mentioned before all the factories Risso and San Salvador. These two establishments work up about 80,000 head of cattle a year. At the beginning of last year the Liebig Company also bought large tracts of land in Paraguay for the purpose of breeding cattle and establishing a large meat factory there. Recently sanctioned laws grant to meat factories exemption from taxes and certain privileges. I only mention the most essential ones: a) Free entrance of the machines and other constituent parts of the equipment or of the buildings, of the material for packing, of salt and of all the other necessary substances. &) Exemption from export duties for the products and by-products of this industry. c) The time during which these laws, granting privileges to factories of corned beef, preserves and meat extracts, remain in force, is ex- tended to December 31st 1920. A new law granting privileges to refrigerating establishments was sanctioned on July 1st 1910 by the Government of Paraguay. The principal provisions of this law are: a) Exemption from every import duty for machines, tools and imple- ments, spare parts and accessories destined for the equipment of refri- gerating establishments as well as for the materials for the construction and the insulation of the refrigerating-chambers, for the substances necessary for their working, and the materials destined for the manu- facture and the packing of export goods. b) Exemption from every export duty for frozen or refrigerated meat and other edibles produced in the above-mentioned enterprises. c) Exemption from all government and municipal taxes for the premises of the factories and their operation. The exemption from duties and the privileges to which the above articles refer expires on December 31st 1925. The conditions of climate in Paraguay are such that spring begins in the region of the Rio de la Plata when Buenos Aires and Montevideo are in full winter. Thus, while the gardens of the Argentine Republic and of Uruguay do not bear any fruit, those of Paraguay yield their delicious fruit in abundance. * - 1098 This peculiarity of the extremely varied production of fruit in Paraguay might, apart from the first-fruits preserved by refrigeration, bring enormous Quantities of fruit to the markets of the region of the Rio de la Plata, and as far as special kinds of fruit of the country are concerned, as for in- stance the guava, etc., their export to Europe might be successfully tried, where the novelty and above all the delicious flavour of this — for the European — exotical fruit would secure it an important and remunerative market. In conclusion I would mention that the day is certainly not far off. when the whole of Europe will take a lively interest in this young Repu- blic, and it would be desirable that this might be the case as soon'as possible or rather — in so far at least as we Austrians are concerned — from this very moment. -- 1099 Present Situation of the Refrigerating Industry in the French Colonies. By André You, Director of the Colonial Office, Delegate of the French Colonial Office at the 2* International Cold Congress. It seems to me that a concise statement of the present condition of this Industry in the different French Colonies is an indispensable complement to the report of M. Gruvel, Professor at the Faculty of Sciences at Bor- deaux, who was commissioned to study on the spot the Cold Industry in the French & foreign possessions on the West Coast of Africa & in British South Africa. Despite the considerable services which cold will undoubtedly render in tropical countries, in contributing to the health, hygiene and comfort of Europeans, you will remark that it is still very little used in our oversea possessions. Martinique. The only refrigerating machine in la Martinique is at Fort de France. It supplies ice for local requirements and to a few ships which call there for stores. It is the common desire of the Chamber of Commerce and of the agriculturists in the Colony, that the ships of the Compagnie Générale Transatlantique should be adapted, by means of the fitting up of cold chambers, for the transport of tropical fruits, more especially bananas. Some of the ships are provided with Isothermal Chambers, but owing to their limited capacity they can carry only a very small part of the fruit which might be exported. This fruit arrives in Europe in a perfect state of preservation; unfortunately in the course of unloading and transport to the markets in ordinary railway cars, a too sudden change of temperature is produced which causes it to rapidly deteriorate. It will therefore be neces- sary to transport these fruits from the ports to the markets in Iso- thermic Cars. From the point of view of the economical development of our colo- nies, this question is of the greatest interest and worthy of the attention of the home trade. 1100 As soon as it is solved, the French market can be liberally supplied with tropical fruits, and European fruits and vegetables introduced into ours OverSea possessions. Guadeloupe. * At la Guadeloupe there are four Refrigerating Works, one at St-Claude one at Basse-Terre and two at Pointe-à-Pitre. - The first two, run by hydraulic power, produce daily 600 & 420 kgs of ice respectively, for the needs of Basse-Terre, the chief town of the colony. They have no cold chambers for the preservation of produce. The two others, run by steam, belong to the Refrigerating Works Company at Pointe-à-Pitre. They produce respectively 200 & 140 kgs of ice hourly, which is amply sufficient for the consumption in Pointe-à-Pitre and the surrounding communes. * { . ." The ice is sold by this Company at 10 centimes per kilo, while that at Basse-Terre costs 20 centimes per kilo. It is desirable that these works should be enlarged so as to allow of the fitting up of cold chambers to preserve temporarily the fruit, and more especially bananas, before shipment. - When a ready sale for this product is assured in a normal manner, la Guadeloupe will be able to do an important trade in it. Guyane. There is no Refrigerating Industry at la Guyane, apart from the ice making machines. But in this colony, as at la Martinique and Guadeloupe, local commerce urges the use of cold chambers on ships for the purpose of transporting the local fruits, of which a large quantity are suitable for export. - Saint Pierre et Miquelon. The islands of St. Pierre and Miquelon form our only cold colony (mean annual temperature 5° C) and the very severe winter facilitates the storage, at an insignificant cost, of large quantities of natural ice. Articles of consumption, especially foodstuffs, are preserved very efficaciously either in chambers cooled with natural ice, or in the open air, during more than half the year. The fishing industry is the only one which might utilize refrigerating machines to preserve the bait for cod (composed of herings), ice stores and on board an apparatus being apt to maintain the frozen bait at a low temperature. -** French Somali Coast. The refrigerating Industry on the French Somali Coast is occupied exclusively with the manufacture of ice for consumption. It is only exceptio- nally, and on a very small scale, that ice is utilized for Industrial purposes. 1101 At Djibouti, the Keverkoff Works, with 2 machines, are capable of producing 2 tons of ice per day of 24 hours. They supply traders at 50 centimes a kilo. * The Franco-Ethiopian Railway furnishes its staff with ice by means of 2 machines producing 200 & 100 kgs respectively. The Company has further started at Diré Daoua (Abyssinia) an apparatus producing 200 kgs daily. It is advisable to improve and especially to extend this Industry for the trade in frozen meat. The abundance of cattle and its cheapness in the region, joined to the nearness of the European market, appear to justify a very close study of the question with a view to the development of an export trade. * * Réunion. At la Réunion there are several machines producing ice, but only for local consumption. Nevertheless, the island produces delicious fruits in abundance, mangoes, pineapples, letchis, bananas, avogados etc., and could produce much more, if it were assured of a profitable sale abroad. It would in this case be necessary to secure low freight rates, so as to allow of the fruit arriving in Europe in good condition and at a low cost. Madagascar. The Refrigerating Industry in Madagascar is so far very limited. There are however some works in the colony utilizing cold industri- ally. In the principal centres of the great island are Ice Works, especially at Tananarivo, Tamatavo, Majunga, Diego-Suarez, Nossé Bé, Anatava and Mananjary, producing several hundred kilograms of ice daily for consumption. The selling price varies according to locality from 30 to 60 centimes per kilogram. For some years past the Silkworm Station at Nanisana, near Tanana- rivo, owned by the Administration, has been making experiments with a view to utilizing artificial cold in the breeding of silkworms and the re- sults are very satisfactory. A Preserved Beef factory at Antongobato near Diego-Suarez, possesses a refrigerating plant, and a refrigerating machine has been fitted up at the Ambochimangakeby Brewery near Tananarivo. The steamers running between France and Madagascar have no cold chambers adapted for the transport of perishable commodities over long distances. - * Now the cattle in our colony is very abundant; after the Argentine Republic and New Zealand, it is the country possessing the greatest amount of cattle per head of population. A large quantity of cattle could therefore be exported, and it is to be hoped that within a short period the Frozen Meat Industry will be established there. 1 102 In the same manner the trade in fruit, which is practically of no value on the spot, might be largely extended, if the ships trading between the great island and Europe were furnished with cold chambers. * Cochin China. The cold industry adapted for the preservation of various products, which might advantageously be exported or imported, is very insufficiently developped in Cochin China. - Up to quite recently it was limited to the production of ice for the cooling of beverages. A Company, entitled 'Société d'oxygène et d'acétylène de l'Extrême Orient was founded last year. Its main object is to work the autogene soldering process. This Company utilizes in the manufacture of oxygen the liquid air processes of George Claude. Work was started on the Ist August last. I should like to draw your attention to the fact that there is a wide field for the Refrigerating Industry, not only in Cochin China, but also over the Far East. This organization might be undertaken by the Shippig Com- panies, whose ships at present have only cold chambers for their own food stores and for the transport of some early fruits and vegetables, which are eagerly bought up on their arrival by the more well to do part of the European population. West Coast of Africa. As M. Gruvel in his report gives full particulars of the refrigerating plants existing in the European possessions on the West Coast of Africa, I will only deal briefly with the subject, leaving you to study M. Gruvel's report if you desire more complete information. As you will remark, the Cold Industry is very little developped in the different French Colonies on the West Coast of Africa. It consists solely in the production of a more or less considerable quantity of ice, often made with old and uneconomical machines. In certain hospitals ice is entirely wanting, although all colonial doctors agree as to its valuable therapeutic aid in the cure of a number of diseases common in tropical regions. It is desirable that the more important centres should obtain fresh provisions from the Shipping Companies organized for the supply and that they should have cold stores for their preservation. Europeans, who are often reduced to live almost entirély on preserves, would thereby procure a hygienic alimentation which would exercise a very favourable influence on their health. 1103 French Equatorial Africa. In French Equatorial Africa there are also only a few machines making ice for local consumption. No Refrigerating Plant exists and such an in- stallation would perhaps at this period be premature. - Gentlemen, in all the French possessions the work undertaken by the Cold Congress is being followed with interest. Possibly it will lead the countries oversea to develop their Refrigerating Plants for the profit and welfare of their inhabitants. In the name of the French Colonial Minister and of the French Colo- nial Administration I congratulate and thank you for your science, your devotion and your praiseworthy efforts. 1104 Second Report on the Application of Mechanical Refrigeration in the Netherlands. By the Office for Foreign Commercial Relations, Director O. Kamerlingh-Onnes, Amsterdam (Charged with the Information Service of the Nederlandsche Vereeniging voor Koeltechniek"). Our first Congress report of 1908 communicated the general and the statistical data for Holland and her colonies. It was supplemented by a chart. Both were included in part 3 of the published transactions of the First International Congress of Refrigeration held in Paris. Since this first report was drawn up time has been too short for this industry to show important innovations. The following statistics indicate however that general activity in Holland in the application of mechanical refrigeration increased considerably during last year: Exports from the Netherlands in 1909: Dairy produce . . . . . . . . a º e is 88,172,020 kilogs. Artificial butter . . . . . . . . . . . . . 47,884.150 - Fruit . . . tº e º sº a tº . • * . . . 91,341.333 * Vegetables . . . . . . . . . . . . . . . 170,254,912 > Meat . . . . . . . . . . . . . . . 64,349.679 × Beer . . . . . . . . . . . . . . . . . 26,492.345 x Chocolate . . . . . . . . . . . . . . . , 7,015.254 » Fish . . . . . . . . . . . . . . . . . . 172,123.538 x According to the official statistics that appeared lately, but which only furnished data up till 1908, (the statistics mentioned previously dated from 1906) there were 880 cooperative dairies and 341 non-cooperative in Holland in 1908. The general Netherland Dairy Co. was connected with five dairy companies numbering 387 dairies; there were three companies, with 109 fac- tories, who were not connected with the General Co. 1105 The production of each province shows the following figures for 1908: * Production!) . Province - Butter Cheese kilogram mes Groningen . . . . . . . . . . . . 1,943.796 1,011.000 Friesland . . . . . . . . . . . . . . . . 15,284.800 28,875.000 Drenthe . . . . . . . . . . . . 4,059,047 sºm- Overijssel . . s tº . . . . . . . 4,613.724 700,000 Gelderland . . . . . . . . . . . . 5,843.306 200,000 Utrecht . . . . . . . . . . . . 598,000 100,000 Noord-Holland . . . . . . . . . . 1,295.736 8,434,000 Zuid-Holland . . . . . . . . . . . . . 1,915.400 900,000 Zeeland . . . . . . . . . . . * ... º. 185.863 30,000 Noord-Brabant . . . . . . . . . . 5,827,994 250,000 Limburg . 2,892.413 *- All Holland . . 44,460,079 40,500,000 A r t ific i a 1 Bu t t e r. In the last report the name of the district » Ossº was left out through an error. - Mu n ic ip a 1 s ] a ugh ter h o use s. The new house at Sittard must be added to the last statistics. .* Exp or t of can d les The export of stearine candles amounted to 3,539.356 kgs, in 1909. • O verse a tra n s p or t. The undermentioned ships of the most im- portant steamship lines of Holland are fitted with artificial cold installations. Steamship Company , Nederland“, Amsterdam. - * Ton. Ton. • Koningen Regentes& . . . . 3618 > Oranje, * & © . . . 4413 > Koningen Wilhelmina « . 4377 - Rembrandt. . . . . . 5860 Koning Willem I. . . . . 4448 • Vondels . . . . . . . . 5847 » Koning Willem II & . . . 4293 > Grotius & . . . . . . . 5858 » Koning Willem III. . . 4526 > Prinses Juliana< . . . . . . 8300 Königlich Holländischer Lloyd, Amsterdam. *Hollandia . . . 7300 Ton. with 180 m3 cold storage”) »Frisiac * * 7450 > X 180 * > X »Zeelandia.< . 8000 × » 160 x > > *) This table does not include small operations on peasant farms. *) Excluding plant for ship's provisions. 1106 Königlich West-Indischer Maildienst, Amsterdam.') Ton. Ton. *Saramacca. . . . . . . 3275 > Suriname< . . . . . . . . . 3284 • Marowyne< . . . . . , 3.192 * Coppename< . . . . . . . 3193 Rotterdamsche Lloyd, Rotterdam. t *Tamboras . . . . . . . . . 5602 Br-Reg-Ton. Königliche-Paketfahrt Gesellschaft, Amsterdam. Br.-Ton. Br.-Ton. > V, d. Hagen . . . . . . . . 3033 » de Klerks . . . . . . . . 2035 > v. Heemskerk: . . . . . . 2995 • v. Riemsdijk . . . . 2031 » v. Linschoten & . . . . . . .3004 >Duymaer van Twist. . . 1993 > v. Waerwijcks . . . . . 3039 •v. Noort. . . . . . . . . . 1993 ... ? Le Maire. . . . . . . . 3025 >Elout: . . . . . . . . . 1800 > v. Spilbergen . . . . . . 2994 »Russkes < . . . . . . . . . 1800 > Baud & . e & e º a . . .2777 »Reallº . . . . . 1333 » Rochussen & . . . . . . . . 2776 >Coens . . . . . . . . . 1331 » Champhuys . . . . . . . . . 2776 » Boths . . . . . . . . . 1331 » v. d. Bosch & . . . . . . . 2775 • v. Diemen & . . . . . . . 1245. » v. Riebeeck . . . . . . . . 2755 » de Carpentiers . . . . . . 1244 • Rumphius. . . . . . . . 2548 Holland-Amerika Linie, Rotterdam. Ton. Ton. » Rotterdam . . . . . . . 24.148 »Rijndam . . . . . . . . 12.527 >Nieuw-Amsterdam . . . . 17.150 »Potsdam & . . . . . . . . 12.522 >Noordam.< . . . . . . . 12.531 >Statendam . . . . . . . 10.491 That the endeavours of the Society for Cold Technics have gained the good will of the Netherlands Government is proved by the appointment of Herrn Ingenieur J. F. H. Koopman, Secretary and Treasurer of the Nether- lands Society for Cold Technics, as Lecturer on the science of refrigeration at the Polytechnic University at Delft. The course began on February 3". We note from Herrn Koopman's inaugural address, that he believes the application of mechanical refrigeration, particularly in cold storages, to be of real and great importance for Holland and her colonies at the present moment. Indeed, a lively interest is evident among commercial circles, especially in the colonies. 1) These steamers are chiefly used for carrying bananas from Paramaribo to New York. 1107 Insurance in connection with the Cold Industry. By kaiserlichen Rat Emil. Regen, Director of ,Providentia", in Vienna. Since the most ancient days man has been endeavouring to train the powers of nature to his own use. The First of nature's powers that he com- pelled to serve him was fire. In it man discovered something sublime, God- like. As the source of light and of warmth fire was held in great honour; and just as, according to the Greek proverb, Prometheus wrested their power from the gods of Olympus, so do we find in the ancient history of other peoples, the veneration and even the worship of fire. Warmth was for them birth, growth, prosperity; the creating power and that on which life depended. In cold man recognised decay, destruction, death. In the course of the cultural development of the human-race man gradually discovered, in his eternal musings and strivings, that cold was not a negative, destructive and inimical force, but that in it too, as in all things created by the wonderful wisdom of nature, there lay healing and useful powers. Yet it was reserved for the last decade of last century to penctrate more deeply into the secret character of this power of nature, to recognise its usefulness and to subject it also to the Service of mankind. In the thousands of ways of human industry, we now find the natural power • cold, and its consequences made use of. A gigantic industry with the most multifarious variations is built up on it, and new progress every day opens undreamt of prospects for the future. Insurance, though itself no inde- pendently productive industry is yet, indispensable as replacer and main- tainer of lost or threatened goods, and follows the development of the new branch of industry which is opened by the cold industry with lively interest: The cold industry secures a very extensive field of action to the mission of providing against unforeseen events of an elementary nature, for here risks come into question which originate in a power of nature difficulu to recognise in her inner powers and incalculable in her effects. Here in truth does insurance find the task a sharply accentuated one of relieving industrial undertakings of the greatest amount of elementary and working technical risks. In the first place those dangers have to be provided against that are common to the cold industry as to all other industrial undertakings. So far, 70% 1108 however, as concerns the special dangers lying in the peculiarities of the cold industry, insurance must await the instigation of cold industrial tech- nical circles. Here, too, necessity will be the mother of invention. In other words : the insurance technicist will have to follow the cold technicist. As regards individual branches of insurance; fire insurance, whose uses and importance are unquestionable, must be first considered. Provision against danger from fire has been fully made by a number of the best organised fire insurance companies. The premiums are in pro- portion to the amounts of the outer and inner dangers combined in the fire risks. In calculating the premium the special working conditions of the particular industrial or trade plant are considered. The fire insurance pro- vides not only against damage from burning or lightning but also against damage through explosions of gas or of boilers without 'a special premium being levied. The provision against boiler explosions without special premium is under the condition that the particular boiler is insured by the society at full value against injury through fire. - For damage through explosion of every kind (except through explo- sives) provision is made by fire insurance companies for a moderate addition to premiums which vary according to whether the whole fire risk or only certain parts of it are insured against damage through explosion. Such general insurance against explosion is as a rule only granted by a fire insurance company if the particular objects are insured in the company and the boilers are included at their full value. The conditions under which inflammable stuffs and explosive liquids are used for beating and driving power, and the regulations governing the use of movable power engines and steam producers of fixed and movable motors, also have bearing upon the fire insurance. Explicit refe- rence is made here to the existing inclusive and eventually remissible con- ditions because these have also a special interest for the cold industry. A safe separation of objects and rooms liable to danger from fire and explosion from such objects and rooms as are less liable to these dangers, by means of other rooms as free and large as possible, or where this is impracticable by fire walls, fire proof and smoke proof shutters for communi- cations to such objects and rooms, or by installing fire proof floorings and ceilings will serve to lessen the dangers from fire and to decrease the effects of fires and explosions for objects of the cold industry as for all industrial and trade enterprises. Fire insurance Societies have also introduced the additional insurance against loss through work being stopped at factories and industrial works and for special premiums guarantee against losses caused by such inactivity, resulting from fires, lightning or explosion, on the one hand through loss of income and on the other hand through the necessary expenses for conti- nuation, premises. * 1109 Among the most important tasks that the cold industry will have to deal with is certainly the treatment and satisfactory solution of the question as to what arrangements should be adopted in whole working plants or in separate departments in order to be able so to cool the temperatures of --objects that have taken fire or are in danger of the flames that the fire may be subdued or the danger of taking fire avoided without the objects that are exposed to the danger of fire suffering harm from the cold applied to them, or that greater dangers of explosion be caused. Transport insurance takes in first damage occurring to the means of transport (cold storage ships or waggons etc.) or, further, to the goods for- warded, under the supposition of arising through force majeure. Natural spoiling of the cold goods transported cannot be considered here either, according to the general insurance regulation that damage arising from the nature of the article is not coverable. ... A further insurance would be given for damage happening to cold machines during transport. Insurance against liability can also take a great number of risks off the cold industry. First the liability of the owner of rolling stock, when using his own waggons, through damaging the rolling stock of the railway. Liability of the owner for personal injury through faulty execution of his Waggons. -- Liability against damage in both cases on foreign goods-transports. Working liability both against personal and material damage. Liability of the owner of works for personal accidents through defects in the cold plant (Death at carbonic-acid cold plants through poisoning). Insurance of machines. To this branch an entirely special field is re- served for the cold industry, yet it is only possible here to lay down a few general features, which are proper also to the insurance of machines of other branches, whilst special suggestions, suitable to the peculiarities of the cold industry, must be specially made by this industry to the insurer. For the present the extension of the guarantee for limited time given by the sellers of new machines could be considered. Insurance of machines covers every kind of damage, so far, that is, as it does not arise from ordinary wear and tear or is not a mere bagatelle. The limit for the latter is normally 100 Kronen. A special advantage to the person insuring consists in the fact that he has the right to immediately set about repairing a damaged machine. As recompense for repairs in case of damage 80 per cent. Of all costs arising (exclusive of loss of profit), in case of total demolition 80 per cent. of the value of time, is granted. The manner of insuring above described gives a considerable advantage to the person taking out a policy, for the guarantee of the seller is as a rule limited to one year, and merely limits itself to the factors that are difficult to prove or control: faulty construction, bad mounting, or faulty material used. It is here presupposed that the attendance at the cold plant 1 110 is conducted with especial care, for it is statistically proved that 90 per cent of all machine breakages are due to the negligence of the mechanics attending the machines. In general the wear and tear damages in machine parts of cold plants are but slight. It is a different matter with piping, especially brine piping, where it is necessary to change the pipes in periods of fire to six years. * Typical injuries to compressors are the frequent breaks of the cross bar and the hard corrosion of pistons. Machine insurance accepts only carbonic-acid and ammonia compression machines. Sulphurous acid compression plants are not insured. The reason is the frequent formation of sulphuric acid through air and water forcing in their way into the tube spirals, causing these to corrode. Damage through wear cannot be distinguished from such accidents. Insurance only according to new value. In the case of absolute demolition an amortisation amount of five per cent. per annum would probably suffice. The requirements of power machines for driving compressors, pumps and circulators is normal, or should be described as almost more favourable, for the requirements re- main constant and over-loadings hardly ever occur. >k >k >< In the foregoing I have roughly sketched out, according to the pesent state of insurance matters, by analagous application of other industrial branches to the cold industry, how far insurance can enter into the working of the industry under consideration. With the progressive development and extension of the cold industry, which should gain further popularity through the Congreſs now being held, there will also arise new requirements in the sphere of insurance. It is superfluous to say that insurance, which has for years been ende- avouring to accommodate itself to the requirements of industry, commerce and trade, will also endeavour to meet the suggestions and desires coming to it from the sphere of cold industries, and also to fulfil its national eco- nomical tasks in this branch. 1111 Instruction in cold Technics in Holland. By Dr. M. de Haas, Professor at the technical University at Delft. In consequence of the commission given me by the Dutch Refri- geration Society I have the pleasure to deliver the following particulars concerning the instruction at present given in Holland on cold Technics. It may be granted that in no teaching institute is the instruction in any technical branch such that the student is enabled entirely to conduct such technical work on leaving. Apart from the fact that the methods cf a trade can only be gained by practical experience, every technical branch may be considered with so many other branches of Science and technics and further, is subject to so continual expansion and development that the instruction must be limited to individual features. This limitation is further settled by the kind of institution at which instruction is given. This is especially applicable to instruction in cold technics, which branch, moreover, at all events at the present time, cannot be called the principal object of instruction in any institute in Holland. Not only in in- struction but in actual practice also, this comparatively young branch of technics demands a specialising and dividing up of the work. The theory, the construction, the examination and the management of cooling machines, all require of him who devotes himself to them, a special education and experience, and although the man who has to construct or to manage a cooling machine cannot manage without some knowledge of the theory, and the theoretical man must know something of the con- struction and management of the machine, yet in instruction or in the work itself a particular person will develop one direction more than another. The same remarks apply also to the applications of cold technics. Artificial cold is applied in cool rooms for the keeping of food, flowers, furs, in abattoirs, breweries, dairies, in metallurgy and various chemical in- dustries, for transport purposes, deepening of shafts, or in building sub- terranean railways etc. In each of these applications spheres of other sciences, as for example, chemistry, biology, botany, metallurgy. ship-building, knowledge of explosives, of national and international civil law and many another. 1112 Evidently at the technical university it is only possible to give the student such a grounding in all these directions as shall enable him to build up further knowledge. Outside the university, teaching institutes with more limited programmes touching only a few applications of cold technics can also work exclusively in that direction. The above general reasons will be more closely described in the follow- ing paper. I will explain shortly, so for as my knowledge goes, how in- struction in cold technics is given at the various institutes in Holland. 1. Academy for fine arts and technical sciences, at Rotterdam. Course for Machinists. - The instruction in this course for machinists of the mercantile marine, has the object of making these young or older people who are accustomed to handling the various cooling machines and arrangements on board ship acquainted with the principles on which the effect of these machines is based. The piecing together and construction are explained, systems compared and results deduced therefrom. - The manner and extent of this instruction may be further judged from the book “Het Scheepsstoomwerktuig» (The ship machines) by Pro- fessor A. D. F. W. Lichtenbelt, Head master of this academy. This book is used in the machinist's course; cooling machines are dealt with in the third section, 2nd edition (1905), on pages 135–167. - A separate section contains the constructional drawings which are full of detail, while in the book itself there are also many illustrations. It will be seen that the instruction is arranged in the first place for actual practice especially for the application of cold technics on board sea going vessels. Individual definite types of machines are dealt with, for example the dry air cooling machine of Lightfoot, the ammonia machine of Lindé, that of Haslam, the carbonic acid machine of J. & E. Hall, the double COs machine of Haslam, At the same time attention is drawn to various points in the construction such as the arrangement of packing boxes, lubricating apparatus, etc.; the starting and management of the machine are also explained, for example as to how it may be ascertained whether water or too much oil is in the ammonia tubes, or if either too much or too little carbonic acid or ammonia is circulating, and how these : troubles are to be remedied. Then there is a discussion of the fitting up of the coo! chambers on board ships and the various ways in which the cooling follows. . . ** . . . . * , Before this there are some theoretical considerations on gases and steams; at the same time, to give some examples, the law of Poisson, the authority for the revertible adiabatic changes of state in ideal gases, is mentioned and applied, though not derived; the changes of state in vapours' and the propperties of the critical point are illuminated by means of the well known Andrew's Diagrams. - . . . . . . . 1113 2, Educational Institute Society for machinists, Amsterdam, This school comprises: a technical school for machine construction, for electo-technics, and for sugar manufacture; a school for preparation for ship machinists in connection with repetition course : an evening course for machine drivers and stokers. Herr Masch. ing. H. C. Grosjean gives the cold technical instruction in two departments of the school. In section B the arrangement, work and management of ammonia and carbonic acid machines are discussed, yet the theory is hardly touched upon on this point, reference being made to the physics instruction. In section C (highest school class) the instruction is more thorough ; as introduction the teacher deals with cooling by air, the construction and management of the compression cooling machine are explained afresh, whilst finally the compressor volumes for a definite ice production and with a specified refrigerant are calculated. As the director, Herr Enno van Gelder informs me, the instruction is more of less elementary; with so great a quantity of matter for study the necessary time fails for dealing with all details fully. 3. Netherlands Industrial and Commercial School at Enschedé. According to information given me by the teacher at this institute Herr F. H. Eydman jr., Mach. and Chem. engineer, the instruction on indu- strial matters is limited to the textile industry. Artificial cold is little used in this; only in dying various development colour stuffs and for mercerising yarns or textures. First a cooling apparatus would not pay its cost, and secondly a cooling is not absolutely necessary. As a matter of fact mercerising is still so little done in Holland that it seems unnecessary to deal with cold technics as a side study. 4. Königliche Seekadettenanstalt at Helder. Since the introduction of smokeless powder war-ships supplied with such and which visit the tropics are fitted with powerful refrigerators. The chief object of these is to prevent the ammunition room temperature from getting too high (not over 30° C). Side objects are ice-making, the cooling of store-rooms and latterly also of drinking water. Even the distilled water set apart for general purposes is cooled by means of the refrigerator. On board Dutch war-ships there are at present nine Hall's Refrigerators and three cooling machincs by Haubold; in all of them carbonic acid is used. The explanation of artificial cold to the sea cadets of the school takes place when dealing with ship machines; the principal parts, compressor, separater, regulator and lubricator are described, but the managemeñt of refrigerators is not considered. - *-* * * - - - * * * *- * 1-114 of Thermodynamics, which at this school can be done all the more thoroughly because only those youths are admitted who have passed the Realschul five years' course well. As regards the instruction in Physics at the marine school the book 'Inleiding eot de technische thermodynamicas (Introduction to technical thermodynamics) has been published by Herr Dr. H. G. Oosting, teacher at the school. This also deals with the first and second principles of the theory of heat and various applications of the diagram of temperature . Entropy. Taken all in all the instruction is more theoretical than practical in character. School for Marine Machinists, at Hellevoetsluis. This school provides instruction for aspirants for machinist posts in the Dutch Royal Navy. The instruction is both theoretical and practical, and after the examination is passed the candidates are appointed as under machinists on war-ships. A further examination has to be passed to secure promotion to each of the grades machinist, chief machinist and officer machinist. - -- -. The course at the school is a three years one. . . The cold-technical instruction comprises all that a Dutch naval machinist requires to know thereof, and only deals with the management of cooling- machines that are used on Dutch war-vessels. (See also sub. 4.) Considering the large amount of general knowledge of machines that. must be imparted to the youths, only little time can be given to cold technics. After passing the school and receiving appointment on war-ships the youths are taught how to handle cooling-machines by experienced machinists and officers. The cold-technical matter taught at the school deals in the first place with carbonic acid machines. A short discussion of the properties of carbonic acid is followed by a description of Hall's carbonic acid machine and some particulars about its construction, most attention being given to the management of the machine in practice. Then the teacher goes on to explain the manner of starting a new machine and the after filling with carbonic acid, stating how various evils are to be recognised and what remedies are applicable in each case. Finally an ammonia machine is shortly explained. Such are not yet to be found on our war-ships, it is true, but they are found on several mail-boats. Lightfoot's cold air machine is also explained. The advantages and disadvantages of each system are mentioned. Thus the instruction is almost entirely of a practical nature. Higher Military School, Hague. Herr Dr. W. Stortenbeker, teacher of Physics at this school, informs. me that cold technics are not included in the instruction given at the Schoo!, 1115 National Veterinary College, Utrecht. Here young people are trained for veterinaries. The veterinary diploma is granted after an examination is passed in Physics and in veterinary science. - - Herr Dr. G. D. van der Plaats gives some time to cold rooms and refrigerating apparatus in slaughter houses in the Physics lessons, during the first year, and the demands made thereon. The only machine explained in detail is Linde's ammonia machine, which is in use at the Utrecht abattoir; this abattoir is, moreover, visited as part of the instruction. In the instruction in theoretical meat inspection, given by Herr Dr. H. Markus, formerly personally occupied at the abattoir, only the meat and not the arrange ments of the slaughter house are dealt with, owing to insufficiency of time. Herr K. Hoefnagel, director of the municipal abattoir in Utrecht, gives instruction in practical meat inspection. The scholars visit with him the abattoir and cold stores in Utrecht and are shown the cooling machines. At times other cooling installations are visited, whose construction differs from that of this abattoir. The instruction in meat inspection is given during the last year. Fishery Schools. I am informed by Herr Dr. P. P. C. Hoek, scientific Fisheries adviser, that no instruction in cold technics is given at these schools. The instruction intended to be given is only elementary and the higher parts of the technique, as also fish preservation, are not included in the teaching pro- gramme. Higher National Agricultural, Gardening, and Forestry College, at * Wageningen. At this institute Herr S. Lako, agricultural engineering teacher, deals with cooling machines, as regards their use in dairy farming on a large scale. He explains the general objects and, -more fully, also the various systems of cooling machines used in dairies. F urther, also the theory of these machines and something about their construction and management. Ilimitation is necessary here, also, as the quantity of matter to be studied by the future agricultural experts is very great, as it is, and embraces many dif- ferent subjects. National Dairy School, at Bolsward. \ Herr Dr. H. J. Slyper, teacher at this school, lately published a small book • De Compressiekochmaschiness (Compression cooling machines), con- taining short treatises on the principles, construction and application of such machines, for the use of owners of cooling installations, manufacturers, and technical students. The production of this booklet is connected with the 1116 cool-technics instruction given by Herr Slyper at this school. It seems to me that this little booklet, which as far as I am aware, is the first work in this sphere written in Dutch, could be used with great advantage at many colleges. Naturally the contents are but of an elementary nature, yet the subjects treated are, within these bounds, very well chosen. In chapter 1 the importance of cooling machines is considered. Chapter 2 describes ammonia, sulphuric acid, and carbonic acid machines. Chapter 3 treats of the use of cooling machines, ice-making and the cooling of rooms. Chapter 4, speaks of the management of such machines. Chapter 5 shows how to estimate the productive power of cooling machines. Further, in an appendix, a summary of the science of heat is given. This appendix contains 14 tables, while the booklet, numbering 86 pages, contains 71 illu- strations. At the end there is an account of the literature made use of by the author in putting the work together. As the author says in the introduction, the instruction given at the school is less detailed than in the booklet ; this instruction is, however, illu- strated by drawings and also by visits of inspection to cold installations. Technical University at Delft. Everyone is admitted to the examinations at the university, however he may have gained his technical knowledge, who has a card of admission to the study at the university, which card can be delivered on passing an examination mentioned in Article 123 of the law of higher public instruction. Such card is equal to the certificate of admission to the mathematical and physical faculties at the university. Further by Royal disposition it is permitted that entrance to the examinations of the technical University may also be granted on the basis of certificates given by foreign teaching and experimental institutes. - From this may be gathered the degree of education of the students at this university at the commencement of the course. • . Further some particulars of the instruction in cold-technics at the university are stated. -- In the first year the readings in general Physics include: Properties of gases and vapours, Hygrometry, the measurement of temperatures and quantities of heat, changes of aggregate state, liquefaction of gases, the kinetic gas theory, the first principle of the mechanical theory of heat. In the second year the so-called technical science of heat is taught. This comprises, in the first place, the mathematical treatment of the first and second principles of the mechanical theory of heat, whilst besides Entropy other thermo-dynamic functions (free energy, thermo-dynamic Potential) are. also discussed and explained. Further various applications are considered, oamng which we mention: the conversion of steams and liquids, the equili- brium of two and three phases of a centralised stuff, the phase rule, the 1117 revertible and non-revertible adiabatic expansion of steam, the diagram of temperature Entropy, the theory and effect of caloric cooling machines. Individual types of the last mentioned are discussed but the con- struction of individual parts and the practical management are not consi- dered. This part of the instruction is illustrated by wall pictures, whilst a small compression ice machine belonging to the physical laboratory is explained, which is worked with sulphuric acid and electricity. A chemical factory near at hand is also visited for inspection of its ice - maching, System Lebrun. This course also includes the calculation of the spread of heat through radiation, conduction and convection, also in direct current and counter current apparatus. In a course on auxiliary engines on ships various cold installations arc also discussed that find application on ships. - Finally the courses and practical lessons in general machine con- struction, Chemistry, Bacteriology, Building, Mining, science of working, etc. are also of importance for the instructions in cold technics. We will go no further into these points but only mention that in the section • Building materials & a small ammonia ice machine is at disposal for the examination of the behaviour of building materials at low temperatures. Though opportunily is offered of obtaining considerable and important knowledge for the study of cold technics, yet, clearly, complete opportunity for a theoretical and practical preparation is not yet given at the technicai university to those who wish to specialise in cold technics. In the report on the first International Congress the requirements necessary for such preparation are described as follows: “Le congrès émet le voeu: Qu'un enseignement theorique et pro- fessionel, appliqué aux diverses branches actuelles de l'industrie du froid et dirigé vers de nouvelles applications, soit institué auprês des laboratoires Scientifiques et des écoles secondaires supérieures techniques et commerciales des différents pays, et complété, Sous la direction des spécialistes, par l'étude pratique et détaillée d'établissements frigoriques importants et l'expéri- mentation raisonnée des machines qu'ils comportent.* In order to be able to satisfy these requirements there is necessary, in the first place, a teacher of cold technics, the spécialistex mentioned, and in the second place a somewhat larger cooling machine together with accessories, for examination and experiment. * There is good prospect, however, of these desires being soon fulfilled. In the last speech on this subject by the Rector magnificus on the 10 January 1910, the following passage occurs: « Were the wish of the Senate fulfilled a chair for airing, heating and cold technics had been filled in 1909; the Budget shows that not even in 1910 will this demand be satisfied.». From this it is evident that the Senate of the technical university are endeavouring to effect the installation of such chair, and we may hope 1118 therefore, that these endeavours will terminate successfully within a rea- sonable time. As regards aids to this end, I am pleased to be able to state that a new building at Delft will soon be completed, at which instruction in machine construction, ship-building, and mechanical technology will be given. There are spacious rooms in the building for the installation of a machine Laboratory and there is no doubt that due recognition will be given to cold-technical experiments. - Herr J. F. H. Koopman, machine engineer and secretary to the Dutch Käkteverein, has, meanwhile, been installed as lecturer on cold technics at the technical university; on 3” February 1910 the first public reading was held and attracted great interest. Herr Koopmann selected as his theme for the rest of the course “Die Kühlhäusers, which attracted not only students of the technical university but also people from other circles. Conclusion. Herewith I end my statements on the position occupied by instruction in cold technics in Holland. It follows therefrom that so far as this instruction is given at schools 1—10, it is only secondary; the impression is gained that the time at disposal is used as advantageously as possible in order that the students of cold technics may gain so much knowledge as is requisite for the carrying out of the special work which the instruction given in each of these schools aims at. As regards the technical university, the cold-technical instruction cannot at present be described as sufficient, but, as before remarked, we may rely on it that the Qrganisers of the technical university will understand how to adapt the institute to the new requirements. This would benefit not only Dutch industry and commerce, but would be advantageous as well to the other teaching institutes. %. The Cryogenal laboratory of Herr Professor Dr. H. Kamerlingh-Onnes at Leyden, has not been mentioned in this paper, for the reason that in my opinion the work and achievements of this laboratory cannot be con- sidered as directly belonging to instruction in cold technics. Apart from this opinion it may be taken for granted that the work of Herr Professor Dr. Kamerlingh-Onnes in this sphere enjoys such general fame that it seemed to me superfluous to discuss it in detail. Delft, 30 March, 1910. 1119 The Present Status of Instruction in Refri, geration. By Mr. de Loverdo, Engineer, General Secretary of the International Association of Refrigeration. Af The development of the Refrigerating Industry — every day greater — makes one feel more and more the necessity of organizing the teaching of Refrigeration. This teaching would have the advantage of training both technical engineers who, while becoming useful helps to Engineering firms, would also endeavour to improve the existing machinery, - and specialists who could with great advantage organize, direct and improve the applications of low and very low temperatures in their several lines; these being very likely to pervade more and more other Industries that do not even know of their existence. As yet the organization for teaching refrigeration has hardly begun. Professorships for the science and industry of Refrigeration exist in Germany, France and the Netherlands. Y * Germany. In Germany there are two courses of lectures at the Berlin Polytechnic School in Charlottenburg, one given by Professor Leist on >The technical side of the Production of Cold K and the other one by Doctor Engineer Heinel on the x Gas Condensing and Liquefiing Machinery <, especially the Refrigerating Machinery. - -- Professor Leist's course is on the theoretic aspects, whereas Doctor Heinel's includes two distinct branches, the first of which concerning the Production of Cold. Among the subjects included in this part we may mention: Pressure, evaporation, specific heat, heat of vaporization and the critical temperature of liquefiable gases. Coefficient of conductivity. Surface of heat ex- change. Absorption machines. Building of compressors. Attainment of very low temperatures. Purification of gases by cold. * The second part of the course includes the applications of low tempe- ratures, calculations for industrial plants, execution of plants, etc. Construction, starting and operating of Refrigerating plants. g Moreover a certain number of lectures bear upon the subject of marine refrigerating plants. Those lectures are given by teachers of shipbuilding and marine engineering. France. In France refrigeration is taught at the High School of Aeronautics and Engineering. The lectures given in that School by M. J. de Loverdo include a certain number of subjects, the principal of which are the fol- lowing. - * * M e ch a ni ca 1 Pro duction of Col d. Machines based upon physical phenomena, air, liquefied gas and steam machinery. Machines based. upon chemical phenomena: ammonia and Sulphuric acid absorption machines — Refrigeration units. – Proprieties of Frigorific agents. Theory of Refri- gerating Machines: Wet and Dry compression. Construction of compressors; Piston, Stuffing-box, valves, lubrication, safety apparatus, Condensers; Calculations for Submerged and atmospheric condensers, Refrigerators; Construction and size of refrigerators. — Impro- vements in the condensers and refrigerators of refrigerating machines. – Rotative steam-engines. – Testing of Refrigerating machines. Direct and indirect refrigeration of premises. Calculation of surface. — Frosting and defrosting of the refrigerating pipes. Calculation of surface and ventilator. — Measuring and controlling instruments. Design of a Cold Store: calcu- latinons for its erection. — Ice manufacturing works: various methods of manufacture. — Design of ice works: calculation of the necessary refrigeration – Design of freezing works, of a brewery, of a public slaughter-house, of an industrial dairy. Frigorific transport; refrigerating cars and ships. Refriger a ti on build in g. — Building of a cold store. — Insu- lating materials. Physical and mechanical proprieties. Of these materials , , methods for testing them. Choosing the materials to be used according to the conditions of construction. — Calculations for the insulation of a frigo- rific chamber with a certain given loss. – Calculation of the surface to be given to the refrigerating pipes. - On the other hand, M. Sauvage, the learned Professor of the School for Arts and Trades,') is giving this year a course of ten lectures on the question of Refrigeration. These lectures, which take place in the evening are attended by a great many engineers and mechanics. Diploma of Refrigerating Engineer. The French Association of Refrigeration has appointed a Committee composed as follows: 1) Conservatoire des Arts et Métiers. 1121 . MM. d’Arsonval, Gautier and Tisserand, of the Institute, Gariel, pro- ºfessor at the Faculty of Medicine; C. Roche, headmaster of the High School of Aeronautics; Barbet, Barrier, Biquart, G. Claude, Douane, Faron, de Goeri, Guidin, de Loverdo, Maurice Quentin, Poulain Bonjean. . . This Committee has worked out a program bearing upon the follow- ing matters: Curriculum establish éd for the degree and dip 1 ome R. E. 10 The Science of Refrigera- tion. 20 Refri- gerating machinery. 30 Applica- tions of Refrigera- tion. { < Lectures given at the School of Aeronautics in Paris Theory of Physics . Thermo- Mechanics and dynamics. General and biological Che- mistry. Mathematics . Legislation - . . . . . . . . Practical Physics . . . . . . Refrigerating Plants . . Building with insulating mate- rials Application to Hygiene . Application to Food . . . . Mining, Metallurgy and Public Works. Application to Agriculture and agricultural machi- nery. Application to Physical and Chemical Industries. *. Application and use of very low temperatures. Professors: M. Gar i e 1, Professor in the Académie de Médecine. M. S a u v age, Professor in the School of Arts and Trades. M. Gau tier, Member of the Institute. Comm. R O C he, Headmaster of the School of Aero- nautics. . Maurice Qu in tin. . Ce 11 e r i e r, Professor in the School of Arts and Trades. . B a r r i e r. . Do u an e, Engineer. . Bi qu a r d, leader of the Practical Work in the School of Arts and Tra- des. . de Lo v er do. . Borg e a u. A. Gau tie r, Member of the Institute. Paul a in, Engineer. : . B a r be t. M. Gu is e lin, Engineer. M. G. C 1 a u de. 1122 The candidates for such diploma must already have taken their degree . in one of the following schools: º High School of Electricity — Mining School — School for Arts and Trades – Civil Building Engineer — Agricultural Engineer – High School o Aeronautics — Northern Industrial Institute — Mining School of Saint- Etienne — Lyons Central School — Marseilles Engineering School — Grenoble Electrotechnical School — Nancy Institute — National School of Agricultural Industry, or else justify five years constant industrial practice in some manufacture. Netherlands. It is well known that as regards low temperatures, the Netherlands possess the strongest institutions in the world. The Leyden Cryogenic La- boratory is under the direction of our learned Vice-President, M. Kamerling- Onnes. But since the first International Congress of Refrigeration, the ques- tion of Frigorific Education has been discussed in the Netherlands, and a free course of lectures on Refrigerating Works and Machinery has also been given this year at the Polytechnic School of Delft by M. Kopmann, General Secretary of the Dutch Refrigeration Committee; this course is similar to those of Berlin and Paris. Besides these permanent courses, High School Professors in France and other countries, give a course of lectures on technical refrigeration; thus Professor Wemyss-Anderson reserves part of his lectures at the Liver- pool Engineering School for the question of Refrigerating Machines. Pupils who are especially interested in this question may undergo a probation in one of the numerous Refrigeration works existing in the great English Port. *- In Servia, the Vice-President of the Refrigeration Committee, M. Stanoievitch, has begun, a course of lectures this year on the same question. *. We also learn that Russia endeavors to organize the teaching of refrigeration. In Belgium, M. Hubert, Mining Inspector, gives yearly a certani number of lectures on this question at the Liege Engineering School. As can be seen, the First Congress of Refrigeration has powerfully helped the birth of this special Education. -*. 1123 The Organization of Refrigeration Societies. By Prof. Alois Schwarz in Mährisch-Ostrau. During the last decade the industry and science of refrigeration have developped in quite an unexpected manner. There is no field of human acti- vity as well in industry and trade as in public administration, which will not be found to have important relations to this branch and to have availed itself of the development. In spite of its growth, the importance and signi- ficance of this field of technical sciences has not yet been sufficiently appre- ciated by the greater part of the population; this is chiefly due to the fact that sufficient steps have not been taken to enlighten the public upon this subject, up to the present time. Together with the growth and speciali- sation of technical sciences particular technical Associations for every single branch have been formed, which, by means of publications in technical reviews and papers, as well as by meetings and congresses, have endeavoured to further the interests of their scientific subject. Until a few years ago there was in the Refrigeration-Industry a great lack of these re- sources. England and America alone had some Associations of Refrigeration, proportionate to the importance and extent of refrigeration-industries in these countries. In England the Cold-Storage and Ice-Associations has been in existence for ten years and in the United-States of America, thirteen local Associations of Refrigeration were organized partly for technical partly for business purposes. The first impetus to the organisation of those interested in refrigeration, was given on the continent, in France, where Monsieur de Loverdo, Engineer, proposed to arrange an International Con- gress of Refrigeration, which suggestion was fully supported by the former Colonial-Minister Lebon. This idea met with intelligent appreciation and active furtherance by the whole world. The French Government fully supported the enterprise, eminent Statesmen, such as the Ex-President of the Republic, Monsieur Loubet, the well-known statesman Freycinet, nume- rous present and former Ministers consented to serve as Honorary Presidents, at the head of this Congress. On the invitation of the French Government, special Committees were established in 44 states of the globe, with a view to further this Congress, and they sent official delegates to the same. The Congress has achieved 7.1% 1124 satisfactory results and surpassed by far all previous scientific meetings of the kind. Besides the numerous scientific suggestions received at this Con- gress, the creation of the Association Internationale du Froid & may be regarded as an important result. This Association united those interested in refrigeration in all parts of the world to common scientific and organizing work. At the general Meeting a special report will be made on its organi- zation and activity up to the present time, by the secretary who has deser- ved so well of the Society. Side by side with this great organization, special national Associations of manufactures engaged in any branch of the refrigeration-industry, have. been formed in the various states, in order to protect the special interests of the particular countries on the one hand, and to support and further the work of the Association Internationale du Froids on the other. In most cases the national Associations of Refrigeration sprung from the national Committes established at the Is International Congress of Refrigeration. One of the first to be created was the Association Française du Froid. and this, in consequence of the active propaganda, has developped into a powerful organization which can point to an exceedingly successful activity. In the United States of America the already existing Associations of Refri- geration united into a common one under the title: American Association of Refrigeration.< The next Association created is in Holland *Nederland- sche Vereeniging voor Koeltechnieks a meritorious creation of Professor Kamerlingh-Onnes in Leyden. - This creation was succeeded by that of the * Deutsche Kālteverein & (German Association of Refrigeration) formed at the instigation of the senior-master of refrigeration-technics, Geheimrat Prof. Dr. Karl von Linde. Thereupon the Austrian Association of Refrigeration was organized which was soon followed by the organization of the Hungarian and the Swiss Associations of Refrigeration. No special associations have as yet been formed in the other countries but the Committees appointed at the First Inter- national Congress of Refrigeration have continued their work and have also started the organization of the II. International Congress of Refrigeration. The Russian Committee particularly has been very active, the Italian and the Danish Committees have likewise worked successfully in the interest of the refrigerating industry. As I have been entrusted by the Presidents of the VI. Commission with the report of this organization, I add the following report on the seve- ral Associations of Refrigeration: I. A s so c i a ti on F ran g a is e du Froid. As mentioned above, the same was formed in 1908, immediately after the close of the successful I. International Congress of Refrigeration in Paris. The Honorary Presidency was offered and kindly accepted by the Ex-Presi- dent of the French Republic, Monsieur Loubet and the former Prime-Minister 1125 * Monsieur de Freycinet, further by eminent French scientists as: D'Arsonval, Leauté, Levasseur, Tisserand. The active President is Monsieur Lebon, the former Colonial Minister, who proved such a successful chairman at the I* International Refrigeration-Congress. The Committee of this Association consists of 60 members among whom are representatives of Government, of Industries, as well as of scientific and commercial associations. The organ of the Association is the 2 Revue générale du froid « which also does duty for the * Association internationale du froids. To further the aims of the association local committees have been appointed in the larger cities in France. For the purpose of furthering scientific investigations, the association has its own library of the world's scientific works and periodicals on refrigeration. There is also an office of Inquiry having technical and commercial departments which is prepared to give free of charge to every member any information referring to these subjects. Scientific lectures as well as visits of inspection to large refrigerating-establishments complete this activity. For the study of technical questions special Commissions have been established viz: #. A Commission for liquefaction of gases and of refrigerating-machines, a commission of general application of cold, a commission of the trans- portation of perishable freight, a commission for legislation. To further the interests of refrigerating-industry, national refrigeration-congresses are arranged, the first of which was held at Lyons in October last and numbered 700 members. The association suggested the institution of a special course for the science of refrigeration in connection with the Aviation- School in Paris, and grants a diploma of Refrigerating-engineer tho those passing a thorough examination in all branches of refrigeration. To meet the requirements of the municipality the Association has designed normal- models of municipal abattoirs, which are at the disposal of every town. One of the most important and highly successful achievements of the Association is the creation of an experimentstation in Chateaurenard which is intended to test the most suitable methods of transportation of perishable goods, specially of vegetables and fruit. This plant was built by an expenditure of 75,000 frs, and an annual budget of 15.000 frs. was provided. The number of members amounts to 900 and may reach a thousand before the end of the year. II. Co 1 d-S to r age and I c e A s so ci at i on. This Association comprising Englishmen interested in refrigeration was created as early as 1899 and therefore is the oldest of all existing technical associations. At the annual meetings, the last of which was held in Manchester last year, highly interesting lectures on refrigerating-technics were delivered in connection with visits to various refrigerating-plants. »The Cold-Storage and Ice trades. Reviews in London serves as the associations journal. The association has issued 16 volumes of treatises on mechanical refrigeration. Last year Sir Montague Nelson stood at the head of the Association, he was succeeded by Mr. E. C. Brightman at this year's 1126 election. Mr. Leonard has hitherto acted as secretary and on his resignation the post was filled by Mr. Joseph Raymond. The Executive-Committee for the current year consists of: • Professor J. Wemyss Anderson, Mr. Werby Beaumont, Mr. W. D. A. Bost and Mr. Hal Williams. * One of the most highly appreciated arrangements of this association was the reception given in honour of German Refrigerating-Engineers in London. III. A m e ri can Association of R e frige ration. The thirteen following already existing American refrigerating associations added to the regular membership of those interested in the subject con- - stitute this organization, viz: The American Meat Packer's Association, The American Society of Refrigerating Engineers, The American Warehousemen's Association, The Eastern Ice Association, The Indiana Ice Dealer's Association, The Illinois Ice Dealer's Association, The Natural Ice Association of America, The Jowa Ice Dealer's Association, The Middle States Ice Producer's Exchange, The Railroad Refrigerator Service Association, Southern Ice Exchange, Southwestern Ice Manufacturer's Association, Western Ice Manufacturer's Associations. The first annual meeting occurred in New-York. 376 members have joined this association but it is to be supposed that the number will considerably increase. Mr. Frank D. La Lanne in Philadelphia was elected Honorary-President, Mr. Theo O. Vilter President, Mr. J. F. Nickerson publisher of the periodical Ice and Refrigeration « in Chicago is Secretary. The Association has 15 Committees and Commissions for carrying out its objects. A special scientific and literary committee publishes technical and scientific treatises. The creation of the association was carried out by the first President Mr. Homer Mc. Dainel in cooperation with Mr. Nickerson, Secretary. IV. Ne e der 1 and sche Veree n ig i ng v o or Koe 1 t e ch ni e k. The Dutch Association of Refrigeration was inaugurated by the Dutch Committee in Leyden, on the 23" of September 1908 a few days before the opening of the I* International Congress of Refrigeration. The President is Dr. Kamerlingh-Onnes, Professor at the University at Leyden, the secre- tary J. F. H. Koopmann in Delft. Their official organ is • Mededeelingen van de Neederlandsche Vereeniging voor Koeltechnieks which has already published 13 scientific treatises written by the members. The entire membership is 130, the library of this Association contains 48 numbers. A special Commission has been entrusted with the investigation of methods of freezing and conserving fish. The Association's bulletins are published in Dutch, and English translations are also issued. Recently the Association held its third general meeting in Leyden on which occasion Professor Kamerlingh-Onnes' renowned cryogene laboratory was visited. - 1127 V. German Association of Refriger a tion. This Association was formed Jan. 15* 1909 and numbered at its general meeting in Munich 124 members, at the second general meeting in May 1910 it included 182 members. Privy-Councillor Professor Dr. von Linde acts as Chairman, Dr. Knocke as Secretary. The periodical 22eitschrift für die ge- samte Kälteindustries was chosen as the Association's official organ, it regularly publishes scientific treatises on refrigeration. At the first general meeting in Munich lectures on scientific subjects were delivered by Geheimrat Professor Mollier and Professor Ganzenmüller and such were also delivered at the second general meeting by Dr. Engineer Richard von Linde and Mr. Kögler, director of the slaughter-house. At each of these meetings several interesting refrigeration-plants were visited. For the purpose of study the Association arranged a trip to London in 1909, for the German Refri- gerating Engineers, under the conduct of Geheimrat Professor Dr. von Linde, on which occasion the members of this excursion met with a hearty wel- come on the part of the English Association of Refrigeration, and had an opportunity of visiting various interesting prominent plants under the conduct of English experts: Twenty-two refrigerating-engineers took part in this journey, visits were paid to London, Liverpool, Glasgow and Cardiff and many cold-stores, refrigerator-ships, slaughter-houses and especially the refri- gerating-plants for the cooling of the air blast of furnaces were visited for inspection. On this occassion a member of the Association Oberingenieur Mr. Banfield delivered an English lecture on the German refrigeration-industries. According to the statutes of the Association Scientific subjects are dealt with in three commissions, a scientific, a technical and Qne for legislation and administration as well as for the application of artificial cold. VI. A us trian Association of Refrige ration. º Following the suggestion made by your reporter this association has been inaugurated on June 16* 1909 and numbered 60 members at its foun- dation. Mr. E. Thausing was elected President. Franz Freiherr von Ring- hoffer and Mr. Phil. Porges, General-Manager, were elected as substitutes, Professor Alois Schwarz, Secretary. At the time of its first general-meeting April 2nd 1910 the Association numbered 130 members, amongst which were representatives of industrial organizations, of Boards of trade and of great machine-factories, which joined the Association as benefactor members with contributions of 50–100 K. The Association's organ Zeitschrift für Eis- und Kälteindustries edited by the Secretary to the Association publishes numerous scientific and technical treatises. At the first general- meeting Privat- dozent Dr. Fritz Böck gave an address on liquid air. For the investigation of scientific and practical questions three working-departments were constituted in the same manner as with the German Refrigerating-Association. Besides this, the Austrian Committee issued for the Refrigeration-Congress a beautiful volume containing numerous Scientific and technical treatises. 1128 VII. The Hung a ri an Association of Refrige ration. (Magyar Hütőipari Egyesület.) * The Hungarian Committee has organized the Hungarian Association of Refrigeration which was affiliated with the International Congress of Refrigeration. It has likewise published a monograph on the state of the Hungarian refrigeration-industry. This Association continued existence after the Congress, and was transformed into an independent Association on April 17th 1909. Königl. Hofrat Dr. Ballai is President, Dr. Nandor Kelemen is Secretary. All the members of the Commission of the First International Congress, being enrolled as members of the Association no annual fee has been imposed up to now, consequently the Association has a nominal mem- bership of 230. The Association issues printed bulletins under the title of ~ >Hütöiparº which, however, have not as yet contained scientific essays. Owing to this year's lack of ice, the Association suggested to the Bo- ard of Trade that very important steps should be taken concerning the procuring of ice and the installation of ice-factories, which suggestion was successful. Besides, the Association is engaged in preparing to give information concerning abattoirs provided with refrigerating plants, and moreover it has drawn up a list of books and reviews referring to refrigeration. The preparations for the Second Congress of Refrigeration and specially the plans for the reception of Congressists by the city of Budapest formed the subject of keen activity of this Association. * VIII. Swiss Association of Refrigeration. The Swiss Committee has organized the Swiss Association of Refri- geration, which was constituted Febr. 19th Mr. Buttigaz, Engineer, was elected President, Mr. Damelet, engineer, Secretary. In April of the current year, a meeting was held in Lausanne, and this place was chosen headquarters. No information is at hand concerning the further work of this Association. IX. The Russian Committee of Refrige ration. On Occasion of the I. International Congress of Refrigeration, the Russian Refrigerating-Committee was organized, it continued its work after the Congress, and has greatly extended its organization, so as to perform the functions of an Association of Refrigeration. The enlarged Committee was constituted April 12* and published a long report on its work in Russian and French language. The number of its members amounted to 258 on June 15"; but since then, has increased to about 400. His Excellency, Imp. Russ. Councillor Basil de Denissow is President, Monsieur Wladislaw Shima- nowski, Secretary. Representatives of all Russian Ministries, Railway-Com- panies, of cities and commercial Corporations have become members. The Committee has organized two permanent departments, that is to say, the technical department with an enquiry-office which gives to all interested in refrigeration, information on technical subjects, and the publishing-office to issue articles and papers, dealing with Refrigerating Industries, to undertake 1129 propaganda work for Refrigeration-Science and finally to found a library for Refrigeration-Technics. Besides this the Russian Committee will organize a section for encouraging the export-trade of food-stuffs to foreign countries. The committee is in touch with the large Russian cities, with all industrial and commercial Associations and forwarding-companies, finally with the Several administrative departments to suggest the building of cold-Storage acco- modations for all these lines; and it has submitted petitions relating the furthering of the Refrigeration-Industry in Russia to the State-Council. Moreover the Committee has given a considerable amount of information on the erecting of Municipal Abattoirs and the fitting-up of cold-Stores and it has taken part in the State-Railways trials in transporting fruits in refri- gerating-cars. It like-wise occupied itself with the examination and the deli- vering of expert-opinions on preserving meat intended for the Navy, the preserving and transportation of fish, and with the examination of the legal -regulations for the trade in artificially cooled game. The sum ex- pended for the activity of the Committee amounted to 4000 Rubel in 1909, and the expenditure for 1910 is estimated at 12,000 Rubel. X. Other Committees of Refrigeration. Only a few communications have been published on the activity of the committees in other countries. The Belgian Committee has resolved to form a Belgian Association of Refrigeration, the Italian Committee too has issued an invitation to establish an Association and is preparing to take part in the II. Congress of Refrigeration. The Servian Committee has conti- nued its activity and has been particularly busily engaged in the foundation of refrigerating-plants and slaughter-houses, of cold-storages for the export- trade as well as meeting the requirements of the capital and provincial towns, in preserving fruit, milk, eggs and other foodstuffs. The Committee has likewise suggested the provisioning of the Servian Army with refrigerated meat and the building of refrigerator-cars and refrigeratorships. Further the Servian Committee intends by means of News-Papers-Articles, pamphlets etc. . to call the attention of the public to the advantages of preservation by arti- ficial cold. Finally a course for the application of refrigeration with an ap- propriate laboratory is to be instituted at the University in Belgrade. — The Argentina Committee of Refrigeration whose activity on the occasion of the I* International Congress proved very succesful, has industriously devoted itself to advancing the exportation of frozen meat to European countries, as well as to promoting the construction of large slaughter- and cold-storage houses in Argentina and of ships with refrigerating-equipment. The activity of the Association and Committees of Refrigeration in the several countries will without question be of far reaching importance in the furtherance and propagation of cold-technics and their application. 1131 ** 4: Report of Proceedings of Commission VI. 1* Sitting, 6* October 1910. The Sitting began at 2:25 p. m. and ended at 4:20 p. m. Honorary Presidents: Legationsrat Frederick Adolf Georg v. Be re n- cre utz (Schweden); Staatsrat Basilius v. De n n is s off (Russia); Munizipal- rat Maurice Quentin (France); President: kaiserl. Rat Wilhelm Robert Huber (Austria); Vice-President: Hof- und Gerichtsadvokat Dr. Moritz Weisweiller (Austria); Secretaries: Dr. Karl A sperger, Dr. Moritz Ritter v. Grünebaum (Austria). After the opening of the Sitting by the President there followed the election of the Honorary Presidents. Maurice Quentin (France) gave a paper on "The law as it affects the refrigeration industry and its applications. (See p. 1075). The speaker made the following proposals: It is resolved: I. That the legal work relating to the requirements and the application of cold may be divided into three groups, namely: 1. 2. referring to the object: in general prescriptions, in special pre- scriptions with general application and in special prescriptions; with reference to the origin, in prescriptions that emanate from the power of the law, and in prescriptions that emanate from the executive power (and this latter divided into administrative ordinances of a general nature or such referring to a particular district, circulars referring to individual functionaries, and finally individual prescriptions); ... with reference to the economical state of the country taking part: in prescriptions of the producing countries, in prescriptions of the consuming countries and in prescriptions of those countries which at one and the same time are exporters and consumers. II. The general and special legislation is to be brought into agreement with the progress of the science of refrigeration in the countries in which refrigeration is made use of 1132 These resolutions were unanimously accepted. Exc. Staatsrat Basilius V. Dennissoff (Russia) then speaks on "The acti- & g g /* * wº t vity of the imperial russian committee of refrigerations. (See p. 1086). He puts forward the proposal that the International Association of . Refrigeration shall work to the end that all official and private information be collected which meets with the conditions under which the preservation of those articles of food that are perishable may best be effected in order in this way to be able to make monetary advances on these goods and to protect such against the danger of loss. The International Association shall examine the possibility of founding an international special insurance which shall consider goods preserved by cold and its legal hypotheses in all countries, and in accordance therewith Submit their proposals to the III" International Congress of Refrigeration. This proposal was unanimously accepted. Legationsrat Frederik Adolf Georg v. Berencreutz (Sweden) gives a paper on >The legislation referring to the refriger a ti on in dustry in Sweden. (See p. 1084). Gewerbeoberinspektor Hans Tauss (Austria) gives a paper on The C O m mercial laws and regulations for the m an u facture of ice a n d the co I d plants of the s to re houses in Austria.<. (See p. 1078). The speaker closes with the following words: Gentlemen. I would like now to request those delegates from foreign states to give us some parti- culars concerning the Sunday rests and the permission for Sunday work in their districts; it will certainly greatly interest us to learn the conditions and legal regulations of foreign places. Kommissionsrat Albert Krüger (Germany): In reply to the closing statements of Gewerbeoberinspektor T a uss I would give the following ramarks. I have gathered from these statements that in Austria there are very many difficulties and I am quite astonished that the authorities make so many regulations here. On the other hand I can inform the meeting that for example our company in Berlin 2*/2 years ago set up works to which nothing further was necessary than the permission of the municipal authorities, or of the police for the putting in of boilers. These were then also tested by the revision society where upon the attest was given that the boilers satisfied the police requirements. With that the matter was settled and we had nothing further to ask or to do, the factory could be opened. without any further difficulty. True the question of the smoke annoyance plays an important rôle but one can get over this by putting up one or another motor system. These cannot be used, however, if ice is made from distilled water. With us in Germany artificial ice is made almost solely from boiled water whieh is certainly not the case in Austria. To this end we require various machines, and the only regulation which the policc make with regard to the smoke is that every possible means shall be employed 1133 that modern technics command in order to minimise the quantity of smoke issuing from the shaft. These requirements we fulfilled in such a manner ... that we erected an automatic firing in consequence of which the de- velopment of smoke is so slight that the neighbours experience no anno- yance whatever. It is true, there are also disagreeable neighbours, and such have also complained to the authorities on account of the smoke. We, however, showed the officials who came to us our firing plant upon which the authoritative commission declared that we in this respect were at the head of the times. As regards Sunday rest the matter stands as follows with us. We are allowed to carry on our work until 10 a. m.; the hours from 12 to 2 in the afternoon are not worked at all with us because on Sundays we finish at 10 in the morning. Finally regarding the very important point of working through the whole of Sunday and holidays, which question was also touched upon, we had to deal with the authorities for a long time, but at last we succeeded in obtaining permission to continue our work day and night throughout the whole year, even on the most solemn holidays. We founded our requests, namely, upon the point that the process of distillation cannot be allowed to be interrupted; for if the distillation is shut off the empty pipes might fill with air and the ice would not be clear after the stoppage, but would be so-called milk ice. That was also admitted by the authorities, and thereupon the permission was granted to us to work continuously. 2* Sitting, 7” October, 1910. The Sitting began at 10:45 and ended at 11:50 a. m. Honorary Presidents: Exc. Staatsrat Basilius v. De n n is so f f (Russia): Legationsrat Frederick Adolf Georg v. Be re n cre u t z (Sweden); President. kaiserl. Rat Wilhelm Robert Hu be r (Austria); Vice-Präsident: Hof- und Gerichtsadvokat Dr. Moritz We is w e i 11 e r (Austria); Secretaries: Dr. M. Ritter Grüne b a u m, Dr. A. M. Scheiber (Austria). Kaiserl. Rat Emil Regen (Austria) gives a paper on "In su ra n cle m a t t e r s in the i r c on n e c ti on with the refriger a ti on in d us try.< (See p. 1107.) - The speaker remarks further: I am myself member of the committee of the society of Austro-Hungarian insurance companies, and I can assert that all suggestions that may be given by this Congress or may follow in the future will be welcomed only too gladly by the society of insurance, and will of course be subjected to a thorough study. But it is just as evident, too, that the representatives of the refrigeration industry must approach the industrialists with their wishes. -- . . Not long ago, in a circle of paper makers it was discussed whether paper which at a certain degree of cold was fireproof could then be still * …” 1134 used as paper, and whether this preparation would not be too costly. The machine being by the refrigeration industry exposed to a certain danger from fire is insured like any other machine, on the other hand it offers less danger in many directions. Such desires must as already said be made known to us by the industrial circles. - Fabriksdirektor Arthur Lucas (German Empire) remarks that the statements of Direktor Regen are also of extreme interest to owners of . cold stores and especially the suggestion to protect goods against fire by means of cold; but quite generally such a protection of goods stored in cold houses, and particularly in the case of paper cannot be put into effect because the cost is unproportionately high. For cold stores the question of insurance against indirect harm, which might arise through destruction of the engine by fire, or explosion, etc., is of very special interest, and I will not fail to recognise that great difficulties stand in the way of the solution of . this problem; for the difficulty of such an indirect insurance lies chiefly in the fact that not all goods stored in a cold store that suffer harm or are rendered absolutely worthless can be protected against fire by the cold store itself. If for instance in the engine room of a cold store a fire breaks out, and the work must be stopped for several days, weeks or even months, it is naturally impossible to protect the goods stored there for long periods against spoiling. One must remember that in a single cold store often 10.CO0 to 20,000 cases of eggs are stored, and it is often quite out of the question to realise for the goods in a short time, especially if just this time happens to be an unfavourable conjuncture. The losses thus arising some- times amount to many times the actual damage by fire. It would therefore be of great value both to the owners and users of cold stores if it were possible to arrange an insurance against such indirect dangers without too. high a premium. * Kaiserlicher Rat Emil Regen (Austria): If I may reply I would like to refer to my paper where it is mentioned that the fire insurance societies in their working have also taken up the so-called additional insurance against damage due to the stopping of work at factories and business plants, by which for special premium an insurance is afforded against damage quite irrespective of whether they are caused by the factory itself or by other causes mentioned by the previous speaker. This is the so- called Chómage insurance, and it would be best for the industrialists to approach the insurance societies in order that these might study the matter closely. Of course — as in every case — in the Chómage insurance too, there would have to be limits and cautels, without which, indeed, an in- surance cannot work. Thus, for example, at the arrival of bad conjuncture there can be no talk of insurance of the goods; that is not the concern of the insurance company, but mercantile risk. If, however, in consequence of a fire, the plant of a cold store has to remain out of work, and the goods stored, which require a certain degree of cold, must be disposed of 1135 * * * 3. as quickly as possible and more cheaply on account of their perishable nature, then such a case belongs to insurance. Naturally the insurance people could not deal with the question until exhaustive reports had been received from the interested industrial circles. The question has also been discussed as to whether there does not exist an insurance against the so- called vis propre. If one enterprise supplies a certain degree of cold to ano- ther enterprise it will also take the responsibility for the delivery but will not guarantee that the cold delivered also has the desired effect. In reply to a question in this respect the Commissary General kaiserlicher Rat Sab or sky explained to me that, for instance, from one and the same ox one meat part admitted of being well preserved, whilst another part would suffer though kept under the same temperature. For damage that arises from such inward causes the insurance company could not hold itself responsible, that is in fact the vis propre, There are a number of risks that are quite independent of the nature of the respective article; for such damage the insurance company must give recompense; but for damage which is resultant from the nature of the object or from the will of the possessor it is not liable. Legationsrat v. Berencreutz (Sweden): In connection with this matter I should like to mention that the III* International Chömage Congress, which was held lately in Paris, also passed an arrangement similar to that suggested by kaiserlicher Rat Direktor Regen. Kaiserlicher Rat Emil Regen (Austria) puts forward the proposal that a permanent commission consisting of representatives of industry and of insurance be provided by the International Association for the purpose of dealing with all questions which affect in common the Refrigeration Industry and Insurance. This proposal is accepted. Secretary General Ing. de Loverdo (France) gives a paper on, In - struction in refrigeration « (See p. 1119.) and continues: The complaint may be urged, against the present state of instruction in refrigeration, that insufficient practice is required of persons upon whom a diploma is conferred. The solution of this practical question is most difficult because the private undertakings are not always open to the young engineers, especially if it is a new industry. We in France have tried to create an arrangement whose development will one day enable the young engineer to acquire a thorough practice. I hear mention of the refrigeration experimental station at Châteaurenard. This experimental station is but at the commencement of its develop- ment and will in time furnish an exact picture of a plant destined for the preservation of food products for long periods and for their pre-cooling before long transport. The favourable position of the town Châteaurenard in a great centre of production has made it possible to *. 1136 conduct both these interesting methods of applying refrigeration in this plant. * \ The engineer will there receive explanation not only concerning the working of the engines but also concerning the technics of preservation . and in general concerning the practical hypotheses as they exhibit them- selves daily in industry. * * # Prof. Alois Schwarz (Austria): I consider the question that the reader of the paper has discussed, especially for the conditions ruling in Austria, and Germany, to be exceptionally important. We have gathered from the paper that Holland, France, Russia and Servia have already made a beginning with the very important instruction of refrigeration, while that is still something new to us and in the German Empire. In Austria the introduction of this refri- geration instruction would be particularly important because the knowledge of the application of cold for general purposes is still almost nothing; we still do not know here with what chair of instruction to combine this teaching. I myself, thoroughly convinced of the necessity for refrigeration instruction, have made the suggestion to situate this instruction in the technical uni- versity, as being the most suitable place for it. But some reply that the instruction of refrigeration should be given at the school for engine buil- ding, while others again opine that one should first educate special refri- geration technicists. I now incline to this last view for it is a case here not for the construction of machines or buildings but in the first place for the knowledge of the application of refrigeration to industry and traffic, every- thing else can then soon be carried out. I think therefore that we may so formulate the question by stating that the Congress considers it urgently necessary that in continuation of the resolution passed at the Congress in Paris all technical universities and places of instruction shall be invited to apply their special attention, particularly in consideration of the ever growing importance of the refrigeration industry, to instruction in refrigeration, and to work for the production of a special Chair of instruction, further to direct their attention chiefly to seeing that not so much the building of refrigerating machines, which is already taught at the machine technical department of the institute, forms the aim of the instruction, but rather the teaching of the application of refrigeration in the spheres of industry, commerce and trade. Arnold Brantmai (Russia): I should like to add to the proposal that the technical universieties may cultivate the technics of refrigeration as a science. In my opinion, namely, it is less a matter of the developing of certificated engineers for the application of refrigeration to industry who can construct machines, but rather for people who should know how the cold is made practical use of; the chief importance should be laid therefore upon the teaching of refrigeration and its application being taken up and encouraged in the middle technical teaching establishments as a subject of . 1137 * instruction. In this way enough assistants (fitters etc.) would be educated who could make practical use of their knowledge in the application of cold. Mr. André Lebon (France) remarks that the suggestion to open courses for fitters and mechanics at the trade schools is somewhat too limited, and that it would be more to the purpose to extend them not only to the education of fitters and mechanics but quite generally to the education of engineers. - Without giving them very detailed knowledge of the technics of refrigeration one could quite simply hold a number of lessons or of special courses in order to give them a sufficient survey of this question, which then would enable them to obtain a thorough completion of their knowledge. ^. This system is as a matter of fact followed at the Ecole Centrale in Paris where the students are given a general view of very many industrial branches, which enables them later to specialise. I propose, therefore, that special courses be started at the technical universities. - Mr. M. Hubert (Belgium) remarks that in Belgium no special teaching is given at present, in refrigeration technics. The engineers have interest for obtaining at least general ideas of this question. The mining engineers, machine builders and chemists cannot pass by this question as in their business they often have to put up and make use of refrigeration machines. It seems to me, however, to be most desirable that this general teaching be replaced by special instruction, particularly, as Professor Schwarz has already said, in the various methods of application of refrigeration. I join therefore with the desire expressed in this sense. So far as the lower technical instruction is concerned this is given in Belgium at the so-called industrial Schools, whose lists of subjects vary considerably. It is desirable, however, that at these schools, too, the fundamental ideas concerning the production of cold should be taught; without desiring to generalise this wish one might take the local requirements into consideration. In reality the Schools only turn out foremen. These, in the works at which they are engaged, develop quite remarkable practical abilities, and it is well to endea- vour to give them opportunity so to complete this their practice with the most important theoretical knowledge that they can occupy themselves in a useful way. I think that in smaller states such as Belgium the arrangement of special instruction for refrigeration technics cannot be demanded at every one of the higher technical universities, of which there are five in Belgium; it would suffice to give this instruction at one of the universities at which the already certificated engineers who desire to become specialists can increase their knowledge and perhaps obtain a special award. Ing. D. Jakowleff (Russia): I would like to remark shortly that for Russia not only the question of the education of refrigeration engineers but also the creation of middle teaching establishments in which the application r; r.) f : 1138 of refrigeration can be taught is very important. The same necessity will also exist for other states. In the Kingdom of Saxony there are to-day . perhaps 100 such middle technical teaching establishments, with us in the whole of great Russia at most as many institutes of this kind. I therefore consider it desirable that the II* International Congress of Refrigeration form a resolution to the effect that it considers the creation of middle teaching institutes for the refrigeration industry to be a matter of great importance to the refrigeration industry. --- Prof. Alois Schwarz (Austria): We are indeed all of the same opinion that the education both of higher and lower technicists is a matter of ab- solute necessity for the refrigeration industry. Mr. André Lebon (France) puts the following proposal: > 1. With the intention of spreading the necessary knowledge res- pecting the questions of the refrigeration industry it seems desirable to institute special courses on the application of cold at the higher technical teaching establishments. * 2. In order to maintain a staff of fitters and technicists who under- stand the arrangement and repair of refrigeration establishments it seems desirable to institute special courses at the technical teaching establish- ments of every kind, if necessary with the right of conferring special certificates of efficiency.< This resolution was accepted. Prof. Alois Schwarz (Austria) gives a paper on "The present or g a n is a ti on of the Societi e s of Refriger a ti o ng (See p. 1123) and makes the proposal; -- »The Governments and all other interested bodies are urged to aid the Societies of Refrigeration, which are of the greatest importance for the furtherance of the refrigeration industry, in every possible way, but especially financially and to support their activity in every direction.< Legationsrat v. Berencreutz (Sweden): I should like to add to the proposal: "And to take over the initiative for the formation of such Societies&. - Prof. Alois Schwarz (Austria): The principal thing is certainly that the Governments grant subsidies, everything else we may leave to the refrigeration technicists. The proposal of Prof. Alois Schwarz is unanimously accepted. 3* Sitting, 8* October, 1910. The Sitting began at 10 a. m. and ended at 12 n. Honorary Presidents: Legationsrat Frederick Adolf Georg v. Be re n- . cre utz (Sweden); Dir. Ed. G & r a r d (France); J. F. Nick er son (United States of America); President: kaiserl. Rat Wilh. Robert Huber (Austria); 1139 Vice-President: Hof- und Gerichtsadvokat Dr. Moriz We is w e i 11 er (Austria); Secretaries: Dr. Moriz Ritter v. Grüne b a u m, Dr. A. M. Sch e i be r (Austria). J. F. Nickerson. (United States of America) gives a paper on The in spection of store house ss. Director You (France) reads a paper by Mr. G r u v e 1 on 2T he refriger a ti on in d us try in the French a n d other colo ni e s, on the west c o a st of Africa and in the Eng 1 is h possessions of South Africas. (See p. 1088.) Director You (France) speaks of the * Present st a t e o f the re- friger a ti on in d us try in the Fre n ch colo n i es. (See p. 1099.) Delegate Moriceau (France) remarks that experiments in transporting frozen meat from Madagascar have already begun. Privatdozent J. F. H. Koopman (Holland) reads a paper by Dr. M. v. Haas (Holland) on "The refrige ration technic a 1 in struction in Holian d. (see p. 1111), and continues: Gentlemen, Professor Ha as has in one paper detailed all that is taught in Holland concernig refri- geration technics at various schools. That is very little. It is chiefly a matter of the application of refrigeration machines in various trades. Lectures on pure refrigeration technics such as are held by a professor in Liverpool do not occur in Holland. I am Privatdozent for refrigeration technics; these are of fairly considerable importance to Holland though not of so great importance as in other countries, because we have a fairly cold climate, but it is necessary that work be done in this direction for the sake of our colonies. At the first Congress, two years ago, together with Direktor Ka mer- 1 in gh-On nes, I gave a paper on the application of artificial cold in the Netherlands, namely on the different applications of the refrigeration machine in our country, in the colonies and on various steamers. To this paper I have added an appendix. (See p. 1104.) J. F. Nickerson (United States) puts the following resolution: »1. The II* International Congress of Refrigeration assembled in Vienna expresses the conviction that the refrigeration industry occupies an important economical position, in respect of the preservation of the value of such goods as are perishable, from the time when a surplus exists till the return of the natural equality of supply and demand, so that these goods can at all times be placed at the disposal of the con- Sumers at lower average prices than would otherwise be possible. The development of this business has kept pace with modern pro- gress in the science of refrigeration and has become an important factor for the problem of the distribution of food products. 2. The Congress expresses its full agreement with the legislation and its eventual revision, which may prove necessary after tests have been made and after institution on the part of the government of suitable 7.2% 1140 experiments, for the protection of the interests of the public in every . direction. The Congress declares itself in favour of that legislation which provides for the control of refrigeration stations and for the supervision of all food products liable to spoil, respecting their sanitary condition, from the moment of their admission to the cold store till the moment of their removal for sale. - The Congress further expresses itself in favour of obligatory reports being made to the competent authorities at fixed periods, from which may be seen the total quantity of the various food products that are stored in the cold, as also the monthly movement of these goods, such that the public is completely informed concerning every detail of the conditions.< - * - Direktor Edouard Gérard (France) is against the ice magazines for preserved goods being under stricter supervision than others. He is of the opinion that there might arise in the future a disadvantage for goods preserved in ice magazines, and this might have the consequence that the public be frightened to buy those goods which had been preserved in cold stores. For this reason he proposes to the Congress that this question be reconsidered. • , The proposal of Mr. J. F. Nickers on is accepted. Consul General Leo Hirsch (Paraguay) gives a paper on "The ground a n d climatic conditions, the cattle leases, the slaughter-houses an d the laws respecting the refrige ration free z in g plan ts in the Republic of Paraguays. (See p. 1095.) 1141 - Resolutions of the Commissions I–VI. Commission I. Scientific. The First Commission has expressed the desire : 1. That the International Association of Refrigeration should financially assist Professor Kamerlingh-Onnes in the important investigations he is now conducting concerning the liquefication of gases and the pro- duction of low temperatures. - 2. That the lines upon which the First Commission has heretofore carried on its investigations shall be continued. 3. That the Commission be divided into three Subcommissions viz: a) Physical and chemical. 6) Biological. c) Thermal units of refrigeration. 4. That the next Congress of Refrigeration discuss the subject of pro- tection to and preservation of monuments and public buildings. Commission II. Constructing, Operating and Testing Refrigerating Machinery and Insulating Material. The Second Commission moves: 1. Units. - That the work already undertaken by the First Commission be conti- nued without delay in order that at an early date a final definition and unification of the dimensions, units and rules employed in the technics of refrigeration may be established and that the International Association be as- ked to publish lists of the dimensions, units and rules at present employed in the various countries, together with their relative values. 1142 2. Metals. That tests be made under the auspices of the first commission, in suitable laboratories to ascertain the influence of low temperatures on the properties of metals used in the building of refrigerating and ice- making plants. 3. Machines. I. That the National Associations of Refrigeration, after independent inquiry into the subject, consult together as soon as possible to the end that they may agree upon proper temperatures and pressures and other conditions in the condensers and evaporators of refrigerating machines where the power and efficiency have to be stated in a contract to avoid subsequent disputes. II. That the following tests be undertaken under the supervision of the International Association of Refrigeration: $ a) Tests to determine the properties of saturated and superheated vapors used in refrigeration, and that to this end some leading physicists be invited to resume the work begun by Cailletet, de Mathias, Amagnot and others, more especially with respect to ammonia and methylic chloride, to determine the exact physical properties of these agents. * ô) Tests for the final determination of the specific heat of the more important brine solutions. III. That studies and tests concerning the relative advantages of operating compression and absorption plants with the wet or dry process, and their combinations be continued in the various countries. IV. That refrigerating plants be provided with some simple, practical, inexpensive and uniform apparatuses for determining the power and effect of any part of Such plant, without requiring complicated alte- ration or adjustment for this purpose. V. That refrigerating plants be provided with all reasonable safeguards against accidents endangering life and property. VI. That suitable and simple methods be devised for testing refrigerating machinery of all types, the definitions of the relative power and efficiency of which are to be determined so that comparisons stated in values established by the Congress, may be readily made between machines of various types. VII. That the International Association investigate the use of refrigerating apparatuses to cool large dynamos and motors with reference to their effectiveness in increasing the capacity of such dynamos and motors. 1143 I. II. 4. Insulation. That researches and tests in the various technical Schools and labora- tories for determining the conductivity of the various insulating ‘materials be encouraged and funds provided therefore. Particular atten- tion should be given to the change of the efficiency of each individual layer of insulating material with respect to temperature, moisture, density and thickness. These determinations should refer to the thick- ness of material and temperature usual in refrigerating plants. That at all tests of the passage of heat the surface temperatures of the layers of the insulation be determined to enable exact calculation of III. IV. II. III. the probable coefficient of the passage of heat, which may not yet have been ascertained with scientific accuracy. - That practical, simple and uniform testing methods for insulating ma- terials be determined, suitable to give practical results and develop a correct basis for efficiency and cost of application of the several insu- lating materials. That to avoid any future misunderstanding or disputes the standard surface temperatures of the two sides of the insulating materials for testing as to value be settled upon and that these temperatures be somewhere between — 25° to + 50° Centigrade (–13° and + 120° Fahrenheit). 5. Machines and Insulation. . That investigations be made for the next Congress to precisely define the conditions of acceptance and the different tests as to strength, quality etc., of the materials and parts employed in the construction of a plant, and to determine regulations and rules for the construction of such plant and its control during the test. That the National Associations institute inquiries concerning the effi- ciency of existing plants in their countries, from an economic point of view. That the operation and results of tests of machines and insulating materials, as well as the assembling of plants, undertaken either by laboratories, technical shools, technical societies or manufactures, be sub- mitted to the International Association to enable the Association either to publish the results, or to collect, compare and place them before the next Congress. 6. Instruction. . That theoretical and practical instruction in refrigeration in technical and industrial Schools be encouraged and that a uniform course of instruction be organized in all countries and expanded by practical and thorough researches under the control of specialists and be sup- plemented by rational testing of plants. 1144. II. II. III. That this branch of instruction be subsidized by the governments, local boards, Chambers of commerce and industrial and agricultural so- cieties, especially to enable the purchase of the requisite apparatuses. 7. Cooperation of public authorities and electric plants. . That considering the importance of the water Supply for refrigerating plants public authorities should reduce the water rates to such establish- ments so as to encourage the use of refrigeration by Small concerns handling perishable food products. ** That the same facilities be accorded in respect to gas and electric Current. e g That the national Associations be requested to prepare and publish tables showing the use of refrigeration in the different industries and which would point out the advantages electric power and gas plants will derive through encouraging those industries. Commission III. Application of Refrigeration in the Food Industries. It is moved: . That the International Association of Refrigeration take the initiative in securing an international conference to be held in Paris in 1911, to which all countries importing or exporting meat shall be invited to send representatives for the purpose of studying and adopting a uniform and international method of inspection of refrigerated meats. . That to attract attention to the importance thereof a Subcommittee of the International Association be formed for the purpose of investiga- tion as to refrigerator transportation facilities, with special reference to the distribution of perishable food supplies to nations and their armies, at times of peace or war. . That sound meat when frozen or chilled and maintained in that state, by the use of modern machinery, is equal to fresh killed meat. . That as a matter of principle the use of chilled horseflesh is not objectionable as human food, providing it is sound and is sold under the name of horseflesh, and a thorough investigation is recommended as to the use of refrigerated horseflesh either for food in general or for troops in certain circumstances during war. This very important question is referred to the Third Congress to be placed on the order of the day. • -> . That all slaughter-houses and central market places be fitted with refrigerating apparatuses. . That, in accordance with the resolutions offered by Argentina, Austra- lia, Great Britain, New Zealand, Norway, Russia and the United States of America, the Second International Congress of Refrigeration held in 1145 Vienna recommends that foodstuffs, which have been handled by 10. s modern refrigerating methods, in accordance with the laws of hygiene, be permitted to circulate as freely in commerce with different countries as free products. That restrictions upon the introduction of refrigerated meats which would benefit the public by this addition to their food supplies, be abolished or modified with due regard to reasonable regulations to ensure sound and perfect meat. That the Commission support the resolution passed in Paris at the First International Congress of Refrigerating Industries against the adul- teration of food and adds that such natural ice as is used in the chilling or freezing of food should be taken only from water, which is not objectionable from a hygienic point of view. . That the Second International Congress of Refrigeration re-affirm the resolutions adopted at the First Congress on the question of refrige- rated meat and express the conviction that the sanitary inspection 11. 12. be identical in all countries. That the Congress supports the final conclusions of Dr. Messner in his report, as follows: That there should be an increase as soon as pos- sible in the number of refrigerator cars on the railway lines particu- larly concerned in the transportation of perishable food products and that food products should be carried by fast trains. That the Third Commission expresses the wish that the report of the Spanish delegate, M. Lecomte, be submitted to the International Asso- ciation of Refrigeration, to study the possibility of producing with the aid of refrigeration a kind of albuminous food, cheap and easy of assimilation. That the conclusions of Mr. Kaiser be unanimously accepted. (See paper by Kaiser.) Commission IV. º Industrial Refrigeration. It is moved: * That a permanent International Comittee be formed to study the question of the application of refrigeration to the various chemical industries and that the material be collected and a report be submitted to the Third International Congress of Refrigeration on the methods by which mechanical refrigeration can best be utilized in the various branches of the chemical industry. The subcommission ,tobacco" maintains: I. That the application of low temperatures in the tobacco industry is advantageous. a) As a preventive against undesireable second fermentation in the preservation of raw tobacco, tobacco partially manufactured and tobacco completely manufactured. -- 1146 ô). As a means for destroying or preventing the development of objectionable germs on fermented or finished tobacco. That the Congress recommend closer communication with those investigating technical refrigerating problems, with a view to securing further development of the use of refrigeration in this field, and also the making of tests in that direction. II. That the attention of the tobacco industry be called to the following problems: a) In what manner can the treatment of dried or fermented tobacco leaves be benefited by the application of refrigeration without injury to their quality? * b) Can low temperatures effectively prevent mould on tobacco º c) Is it possible in a profitable manner to modify the process of fermentation by the application of refrigeration ? The subcommission recommends that the tobacco industry make tests. Commission V. Transportation. It is moved : 1. That the Congress considers it desirable that International regulations be adopted by the railway administration for the re-icing of refrigerator cars in transit. ' - 2. That the already existing Transportation Commission of the Inter- national Association devote its attention to refrigerated transportation by water in order to obtain uniform action on the part of railway and navigation companies. That it is desirable that said Commission also tabulate the statistics of such transportation and study the practical measures to be taken for improving and facilitating international transportation under refrigeration. 3. a) By adopting higher demurrage charges on perishable goods for failure to unload cars promptly. - 8) By charging for refrigeration by distance rather than by weight of ice furnished. * c) By not including the cost of refrigerating in the rates of trans- portation, but charging for same separately. d) By requiring shippers of perishable goods to give reasonable and definite instructions as to refrigeration, non-refrigeration or ven- tilation in transit. That the Fifth Commission is of the opinion that the Commission of Transportation of the International Association be requested to study the above questions. - 1147 Commission VI. Legislation. ** It is resolved: I. That the legislation concerning the needs and the application of refri- geration be grouped into three classes, viz.: - 1. With regard to the object: Into general regulations, into special regulations, with general application and into special regulations. 2. With regard to origin: Into regulations by the executive power (including administrative regulations of a general kind as well as referring to certain municipalities, instructions to officials, individual instructions). 3. With regard to the economic conditions of the countries involved: Into regulations of producing countries; into regulations of con- suming countries; into regulations of countries importing as well as exporting. II. That general and special legislation be made to conform with the advanced state of the science of refrigeration in the countries in which refrigeration is made use of. III. That the International Association of Refrigeration gather all available statistical information concerning the conditions under which perishable food can best be carried, in order to obtain advances on the goods and secure protection against losses. IV. That the International Association of Refrigeration consider the possi- bility of the establishment of international insurance on goods preserved by refrigeration, examine its legality in all countries and submit propo- sitions referring thereto at the Third International Congress of Refri- geration. V. That a standing committee be appointed by the Congress consisting of representatives of manufacturers and insurance men to consider all questions pertaining to refrigeration in connection with insurance. VI. That in order to extend the necessary knowledge of the question of refrigeration it is desirable to institute special courses in the higher technical schools upon this topic. VII. That it is desirable to institute special courses in all technical schools and award certificates of qualification in order to obtain a staff of competent engineers and erectors who understand the installation and repair of refrigerating plants. VIII. That the governments and all corporations concerned be invited to said the International Association financially in the development of the refrigerating industry. DY. Resolution on cold storage legislation. Where as the subject of governmental regulation of the cold sto- rage of perishable foodstuffs is receiving attention and adverse legislation may result from lack of exact information on the subject, and -** 1148. Where a s it is of the highest importance that only such legislation be adopted as is based upon sound principles and complete information and which will be for the benefit and welfare of the producer and the consumer alike, therefore be it - Resolved. That the Second International Congress of Refrigeration, assembled in the city of Vienna, Austria, affirm its conviction that the Cold Storage Industry occupies an important economic position in its func- tion of the conservation of values in perishable products and in the preser- vation of such goods from the time of excess production through the period of natural scarcity, in order that there may be available to consumers a constant food supply in all seasons at lower average prices than would be otherwise possible. The development of this business has kept pace with modern advancement in the science of refrigeration and has become a large factor in the problem of food distribution. Resolved: That this Congress expresses its hearty approval of such legislation and supervision as may be deemed necessary, after the most thorough investigation and experimentation by competent governmental experts, so that the interests of the consuming public may be safeguarded in every possible manner. The Congress favors such legislation as will provide for the examina- tion of cold storage warehouses as to their sanitary condition and the inspection of all perishable foodstuffs when admitted to cold storage and when removed therefrom for sale. 4- The Congress also favors the compulsory report at stated periods to the proper authorities for publications in totals of the quantity of the different food products held in cold storage as well as the monthly movement of such goods, in order that the public may be fully informed upon the subject. Alphabetic List of Reporters and Titles of Reports. & Report Discussion Andrault Paul, Engineer, Loos-lez-Lille: , Investigations Upon Refrigerators with Frosted Surfaces and Refrigerators with Wet Surfaces. Their Advantages and Disadvantages. Methods Aiming at Uniformity of Production" . . . . . . . . . . . . . . . . # * * * 119 *me Artman see Simony. Babcock Dr. S. M., College of Agriculture, University i of Wisconsin, Madison, Wisc., U. S. A.: : n.The Application of Low Temperatures to the Curingand | Storage of Chedder Cheese" . . . . . . . . . . . . . 430 Bail Professor Dr. Oscar, Prague: * ,The Use of Cold in Bacteriological Examinations“ . . . . 36 Banfield R. C. A., Wiesbaden: ,On the Manufacture of Crystal Ice from Exhaust Steam and the Practical Results Obtained by this Process" . . . 135 i 294 — — ...The Application of Mechanical Refrigeration to Blast ; r Furnaces" . . . . . . . . . . . . . . . . . . . . . 865 || 912–914 Barth Ferdinand, Director of the United Margarine Factories, Vienna: , Application of Cold in Margarine Manufacture “ . . . . . 461 - | Behm see Metz. - | Berencreutz A. de, Chamberlain of H. M. the King of Sweden, Paris: ,The Use of Refrigeration in Sweden" . . . . . . . . . 1084 ºmºmºmºm- Biquard R., Head of the Physics Section of the Testing -- Laboratory at the Conservatoire des Arts et Métiers : ,The Efficiency of Various Methods of Insulating Refrigerated Rooms. Experiments on Thermal Conductivity" . . . . . 206 || 299–300 Bloch Richard, Chief-Engineer of the Orléans-Rail- way Co.: * a Programme of the Commission on Transportation given in the name of the International Commission of Transportation - 2 of the International Association of Refrigeration" . . . . 945 ſ1061–1062 l1067–1072 Bonjean M. Ed., Member of the Superior Council of Public Hygiene in France: aThe Cooling of Water for Public Consumption" . . . . . 542 wº-ºº-º-º: * 1150 * Bontour Emile, Chemical Engineer (E. C. I. L.) of the Rocca, Tassy–de Roux Establishments, and of La. Société Ame des Savonneries de la Médi- terranée (The Mediterranean Soap Company Limited): *The Applications of Cold in the Industrie of Fatty Substances" Borodine Nicolaus, Councillor of State in St. Peters- burgh : - nReport on the Status of the Refrigerating Industry in Russia" Bourgoin M., Naval Artillery Engineer, Paris: n Cooling of Dwelling Apartments" . . . . . Boutaric J., E. P. C. Consulting Engineer, Paris: ,The Application of Artificial Cold to the Rubber Industry" Britzler Dr., Director of the Municipal Slaughter- House, Cologne: ,Changes in the Physical and Morphological Conditions of Food Stuffs (Meat, Fish and Milk) by Cold" Cavalier Paul, Manufacturer of Glue, Givet (Ardennas): , Application of Refrigeration to the Glue and Gelatine Industry" Cizek Louis, Chief City Engineer, Prague: ,The Refrigerating Installations of the City of Prague“ . C/aude Georges, Professor, Paris: *Report on a Liquid Oxygen Life-saving Appliance and on Apparatuses for the Production of Liquid Oxygen" — — a Report on the Recovery of the Vapours of Volatile Liquids by Refrigeration “ . . . . º Corbett Prof. L. C., United States, Department of Agri- culture, Washington, D. C. : ,The Application of Refrigeration to the Retarding of Plants and the Preservation of Flowers" . . Costa Dr. Alexander and Mori Dr. Nello, Veterinary Officers in the Royal Italian Army: ,Experiments on the Preservation of Horseflesh by Means of Cold, and the Use of this Flesh for Food" Cramm Dr. L. E. v., Ministerial-Office for Commerce and Industy, St. Petersburgh: a Presence and Future of the Export of Butter, Meat, Hogs etc. from Russia to Great Britain“ . . . . . . . . . — — Russia's Domestic and Export Trade in Perishable Produce During the last Decade“ . . . . . . . . . . Report Discussion 703 267 818 750 363 738 518. 802 810 -849 339 545 547 634–635 919—920 642–644 642 1151 -- Report Discussion Dennis S. J., Expert in Refrigeration, United States, Department of Agriculture, Bureau of Plant Industry: ,The Precooling of Fruit in the United States" . . . & 464 -** Dennissoff Basile Elie, Equerry to His Majesty etc., St. Petersburgh: The Present Status of the Refrigerating Industry in Russia" | 1086 1132 Dohmann, Director of the Municipal Abattoirs at - Cottbus (Germany): , Appropriate Refrigeration Plants in Modern Slaughter-Houses" 490 * Drobniak Franz, Engineer, Mine Director: , Shaft Sinking by Freezing Process" a s • * * * * * * 872 || 917—919 Dupont Justin, Engineer E. P. C. in Argenteuil, France: , Application of Refrigeration to the Perfume Industry “ . . 74.1 — P Either Wilhelm, Councillor of State, Vienna: n Application of Cold in the Leather Industry “ . . . . . . 766 || 932—933 Eger v. Elgenfeld Zdenko, Professor, Brünn : *The Working Pressures and Effects of Cold Air Turbo-engines" 123 312 Engelmann Eduard, Chief Building Councillor, Engineer, Vienna': n Arrangement and Management of Open-air Artificial Ice Rinks" . . . . . . . . . . . . . . . . . . . . . . 886 || 921–922 Erčan, Dr. Franz, Vienna: » Importance and Application of Low Temperatures in the Textile Industry “ . . . . . . . . . . . . . . . . 774 || 923–927 Favero Primo P. S., Director of the 2 Instituto Bacologico del Consiglio Provinciale d’Agricolturas at Tarento: * ,The Application of Refrigeration to Silk-Worm Culture" . 860 - Figdor Wilhelm, Vienna: - w Zementholz (Converted wood) as Insulating Material “ . . . 219 -* Fleury Mr. P., Marseille: n Refrigeration by Means of Ice Without Machinery" . . . 975 || 1062–1064 - - • | i Gasnzer Paul, Head of electrical departement, Lecturer at the School of Industrial Physics and Chemistry, Paris: »The Cooling of Electrical Machinery" . . . . . . . . . 257 313 !," Gillmann G., Engineer, Lunéville: n Arrangements and Safety Devices for Avoiding or Minimising “- the Damage Done to Compressors and Coils, especially in the Case of Excessive Pressure Accidentally Caused by Mistakes Made in the Working of the Plant or From any Other Cause" . . . . . . . . . . . . . . . . . . 144 -*. 1152 Gore H. C., Bureau of Chemistry, United States, Depart- ment of Agriculture, Washington, D. C.: ,The Effect of Low Temperatures on the Life Processes of Fruits and on the Rate of Fermentation of Cider“ . . Green Van Rensselaer H., New York City, U.S.A.: , New and Improved Arrangements in the Installation and Operation of Ice Factories" a * * * * Grinzweig Max, Certificated Engineer, Berlin: , Cork as an Insulator of Heat" & a e Gruve/ A., University Professor, on Mission, Paris: ,The Refrigeration Industry in the French and Other Colonies on the West Coast of Africa" • * * * * * * * * Guérault Paul, Graduate of the Polytechnic School and as the Pasteur Institute, Fère Champenoise, France: nThe Use of Cold in cheese-making" . . . . . . . . . Guiselin A., Engineer, Secretary of the International Petroleum Commission, Paris: ,The Use of Cold in the Petroleum Industry" — — . The Application of Cold in the Camphor Industry" – — ,The Use of Cold in the Chemical and Physical Industries". //aas, Dr. M. de, Professor at the Technical University at Delft: minstruction in Cold Technics in Holland“ . Heimpel Karl, Engineer, Factory Director, Vienna: ,The Technical Intervention of National Cold Societies in the Building and Management of Cold Plants" . . . . . Heiss H., Director of the Abattoir at Straubing: , Cold Storages as Accumulators for the Provisioning of Armies in the Field. “ . . . . . . . . Hirsch Leo, Consul General, Vienna: - , Data on the Soil, Climate, Ranches and Slaughter-Houses in the Republic of Paraguay" Hoſitsch Alois, Chief Inspector: , Beer Shipmentors by Rail“ . s' e º e º ºr º e Huizer H. D. P., Engineer, Hague (Holland): , Drinking Cups Made of Ice" a * * * * * * * Jacquin Charles, Paris: ,Note on the Preservation of Dead Bodies" Jakozyleſf D., Lieutenant Colonel, Engineer, Lecturer at the Academy of Engineers, St. Petersburgh: ,Concerning the Economies and Statistics of the Utilisation of Heat in Mechanical Refrigeration “ . . . . Report | Discussion 381 -- 260 -- 221 || 302–304 1088 *- 445 --> 677 || 915—917 716 *- 718 º-º 1111 i 1139–1140 268 || 308—312 (314) 347 657 1095 tº-ºs 1044 *-*. 590 tº-º. 816 || – 273 307 1153 3alowetz E., Professor, Vienna: . * a Concerning the Management of Cold Storage Plants“. . §eamcard Paul, Engineer of Arts and Manufactures, Satie Conrad, Chief of the Research laboratory of the Firm Jeancard, Fils & Cie.: . *The Applications of Refrigeration to the Raw Materials of the Perfumery Industrie“ . . . . . . . . . . . . . . . jumau L., Paris: - Application of Refrigeration to the Electric Accumulator Industry" . . . . . . . . . . . . . . . . . . . . . 5uppomi M., Engineer of Arts and Manufactures, Toulouse: - n.The Distribution of Electric Energy and the Application of Cold" . . . . . . . . . . . . . . . • e - Kaiser Franz J., Director of the Wiener Molkerei: , Application of Cold in Public Dairy Management“. . . . Aamerlingh-Onnes H., Professor, Leyden: ,Experiments at the Cryogen Laboratory at Leyden" . . — — ...Second Report on the Application of Mechanical Refrigeration in the Netherlands" . . . . . . . . . . . . Karcher M., Brewery-proprietor, Paris: a The Application of Refrigeration in Breweries" . Ravan, Dr. J., Civil Engineer, Prague: n.The Rational Use of the Absorption Refrigerating Machine in Chemical Industries" . . . . . . . . . . . . . Rerkhoven E. S., Member of the Dutch Committee: , Cold Technics in Connection with the Paraffin Industry in Holland and the Dutch Colonies" . . . . ſº a Kirchacker, Dr. phil., Armand, Chemist, Colourist of the United Dying Joint Stock Company, Printing Manufacture at Möllersdorf: - -- n Effect of Refrigeration on Mercerising" . . . . . . . e s Rirsch Bernhard, Professor at the Technical University, Vienna: - , Experiments on the Change of Hardening Processes of Hydraulic Binders at Low Temperatures" . . . . . . . Roopman J. F. H., Secretary to the Dutch Refri- - geration Society, Engineer Lecturer (Privat- dozent) at the Technical University at Delft, Holland: - ; : The Cooling of Living and Other Rooms in the Tropics" . ºt Report | Discussion 495 agºmº. 742 — T 787 sº- 282 || 312—313 233 sºme -- 412 || 659–662 19 || 71–72 1104 -- 525 - 735 || 923–927 683 || 915—917 696 || 923–927 54 --- 834 * 73 1154 ~ * Arupsky M. A., Engineer, St. Petersburgh: ; , A Method of Reducing the Difference in Temperature which Governs the Operating Expenses of Refrigerator Cars" . . Larsen Georg, Aalborg: wke-icing Refrigerator Cars" . . . . . . . . . . . . . . Leòrou P., Engineer of Arts and Manufactures: i ,The Application of Refrigeration in the Manufactures of : Roquefort Cheeses at Aveyron" . . . . . Lecomte F. G. and Loinville A. R., Engineers at Dax (Landes): * , New Application of Refrigeration in the Preparation of Concentrated or Solid Foods Especially Milk Powder“ . . Lescardé F., Engineer, Paris: ,The Preservation of Eggs by Refrigeration" • * * ~ * Lzernur Francis, Paris: ,Cold Storage for the Envirous of Paris and the Provinces" Linde C. v., Privy Councillor, Professor: , Retrospective and Prospective Consideration of the Develop- ment of the Art of Refrigeration" Löhmis F. B., Governement Inspector of Agriculture at the Hague, and Şong Dr. D. A. de, Professor and Manager at the Slaughter-house at Leyden: n Import and Export of Meat in Various Countries and the Answer to the Question: Is the Import of Frozen and Chilled Meat From Abroad Desirable for the Netherlands? Loinville, see Lecomte. Lorenz Dr. Hans, Engineer, Danzig: ,The Possibility of Employing Turbo-blowers as Cooling- machine Condensers" . . . . . . . . Loreng Dr. Hans, Chief Physican, Lecturer on Surgery, Vienna: * t r »The Application of Cold in Surgery" . . . . . . . . Loverdo J. de, Engineer Professor at the Academy of Aeronautics and Machine Construction: »The Experimental Refrigerating Station at Chateaurenard" — — nºſhe Present Status of Instruction in Refrigeration" McPike Eugene F., Secretary, Railroad Refrigerator Service Association, Chicago, Ill., U. S. A.: . Report Discussion 996 | 1042 453 419 406 498 11 550 128 42 1048 1119 1003 1066–1067 659 295—297 72 - 1135-1138 mTransportation of Perishable Freight in America" . 1065–1066 1155 Marshall Dr. Chas. E., Michigan Agricultural College, East Lansing, Mich., U. S. A.: ,The Effect of Cold-storage Upon the Bacteriological and Chemical Changes in Milk and Butter, as Revealed by .." Laboratory Investigation in the United States" . tº º Martel H., Doctor of Science, Head of the Veterinary • and Sanitary Inspection Service in Paris: ,The Respective Comparative Values of Frozen and Chilled Meat From the Point of View of General Consumption, and More Particularly of the Provision of the Army, the Navy, and Public ànd Private Administrations" Masse M., Engineer of the Agglomerated Cork Com- pany, Denniel & Cie., Paris: ninsulating materials" Matthews F. E. (M.-E.): n New Arrangements and Improvements in the Construction of Apparatuses for Refrigeration. Results of Experiments Thereon" . . . . Merius A., Engineer, Professor at the Academy of Brewery at the University of Louvain: ,The Preservation of Hops after Removal From Cold Storage" Messner Dr. med, vet. Hans, Director of the Abattoir, Councillor of the Ministry for Agriculture, Carlsbad: ,On the Importance of Refrigeration for Foods, with Special Consideration of Milk" . . . . . . . . Metz Friedrich Rudolf, Technical Director, Vienna: ,The Theoretic and Actual Insulating Value of Hollow Spaces" Metz Friedrich Rudolf and Behm A., Vienna: n New Apparatuses for Determining the Coefficients of the Conduction of Heat" • * * * * * * Monti Dr. Eudo, Chemist, late Director of the Laboratory of Experimental Research of the Krios Company, Turin: ,,On the Influence of Recent Improvement in Heat and Re- frigerating Machinery, and on the Progress Made in the Transmission of Energy, Upon the Cost of the Calorie and Frigorie Respectively, and Hence on the Future of a System of Concentration of Solutions by Freezing and by Conden- sation in a Vacuum at Low Temperature" — — ;,Changes in the Physical, Chemical and Organic Properties of Vegetable Extracts, Particularly Wine, Must and Fruit Juices, Caused by Permeating them with Air at a Low Temperature, and the Subsequent Release at Summer Temperature of the Air Thus Dissolved “ . . . . tº e e- * -- ; | Report T)iscussion 386 317 234 145 528 421 239 194 791 796 | | 657 635–637 (638) (639–642) (644, 646–656) 658–659 305—306 933 73% 1156 Mori see Costa. Neff Peter, M. E., Vice-President of the Arctic Ice Machine Co., Canton, Ohio, U. S. A.: ;Conditions of Acceptance, Various Tests (Resistance, Stanch- ness etc.) of the Materials and Parts Entering into the Construction of Refrigerating Apparatuses. Making These Conditions Uniform; Rules to be Elaborated and Methods to be Determined by the International Commission" . . Neuzwºrth Dr. Josef, Aulic Councillor, Professor, Vienna: , Cold Destructive to Monuments" * * * * > * * * * * * * Nickerson J. F., Editor of "Ice and Refrigerations, Secretary of the American Association of Refri- geration, Chicago, Ill., U. S. A.: , Inspection of Store-houses" . AWilsson Lauritz, Christiania, Sweden : , Railway Refrigerator Cars" . — — »Refrigeration in Sweden with Ice and Salt" . . . . . Orshover H. van, Agricultural Engineer, Hoeylaert: *The Preservation of Fruits de Luxe" . Ottendahl M., Engineer, E. C. P., Paris: - ,The Use of Cold in the Manufacture of Explosives“ . Oitmann Heinrich, Engineer, Munich: , Artpumice and Its Use as an Insulator“ . . . * * * * * Pemmington Dr. Mary E., Chief of Food Research La- } boratory, Bureau of Chemistry, U. S., Department of Agriculture, Washington: ,The Refrigeration of Poultry and Eggs in the United States" Pereg Dr. Ferdinando, Minister of the Argentine Republic at Vienna : - ,The Sanitary State of Argentine Cattle" Panckh Rudolf, Engineer (in Reininghaus Brothers' Brewery J.-S. C.) Graz-Eggenberg. , Refrigerating by Ventilation for Ferment Cellars and the Application of this System to Other Cooled Rooms in Breweries" . . . . Poock Gustav, Tobacco Manufacturer, Brazil: * ,The Use of Refrigeration in Destroying Tobacco Worms" Porges Philipp, Engineer, Manager General of the Simme- ringer and Brünn-Königsfelder Machine Factory: n On the Application of Artificial Cold in the Manufacture of Paraffin in Austria-Hungary" . . . * *~. Report | Discussion 174 || 308 (314). 59 * - 4a * 979 || 1064–1065 283 — ` 487 — 895 -º- 245 || 297–298 592 646 565 *º 531 * 673 || 927–932 685 || 915–917 | 1157 * Preissecker Dr. Karl, Financial Councillor at the J. R. General Direction of the Austrian Revenue Board: ,Concerning the Use of Low Temperatures in the Tobacco Industry" . 4. tº ºr a tº ſº & As Preiðram Dr. phil. Hans, Privatdozent at the Univer- * sity and Director of the "Biological Experiment * Station< in Vienna: - , Artificial Production of Low Temperature in the , Bio- logische Versuchsanstalt" . . . . . . . . * e e º a . g is . e. e s a r s s a s e e Quentin Maurice, Advocate at the Paris Court of Appeal, Doctor of laws, Vice-President of the Admini- strative Commission of the International Associ- ation of Refrigeration and President of the Litigation and Arbitration Office, in the Name of the Sixth Commission : ;General Report" . . . . . . . . . . . . . . . . . . . Query Dr. L. C., Paris: ,The Employment in Therapeutics of Liquid Air at –180° C. “ — — ...,Changes, which May be Induced by Cold in the Physical, Chemical, and Morphological Composition of Foodstuffs, Especially Meat, Fish, Milk and Its Products, Fruit etc." Rautenkrantz Johannes, Engineer, Vienna: ,The Electrical Telegraphic Thermometer*. Regen Emil, kaiserl. Rat, Director of >Providentias in Vienna: . - ,Insurance in Connection with the Cold Industry" Reidrer J., Engineer E. P. C., Paris: º, An Application of Cold in Oil-gas Producer Plants" . . Rittermann Daniel, Director of the United Dying Joint- Stock Company's in Möllersdorf: *The Application of Cold in the Production of Azote Dye- stuffs" . . º Roessingh van Jerson J. A., Member of the Admini- stration of the Dutch Railways: , Increase of Refrigerating Equipment of the Netherlands Railways Since the First International Congress of Re- frigeration in Paris, 1908“ . . • s e e º 'º e e Sandras M., Director of the * Compagnie Parisienne de Glace Transparente“ (Evans, Sandras & Co.): ,The Ice Manufacture" tº º Satie see Şeamcard. Report Discussion 665 38 1075 372 84 1107 782 699 1052 901 1131 293, 294 1133–1135 923–927 1158 Satkewitsch Alexander, Professor at the Accademy of * Engineering at St. Petersburgh: , What are We to Understand by the Term", he Efficiency of – a Refrigerating Machine “P . . * * * * * is e º e º & Schiff Dr. Eduard, Professor, Vienna: - n.The Use of Cold in Dermatology" . . . . . . Schwarz Alois, Professor, Mähr-Ostrau: ,The Application and Arrangement of Ozone Apparatuses in Cold Rooms" © g º 'º º * & --> & º t ſº - e — — »The Organisation of Refrigeration Societies" Shipley Thomas, Vice-President and General Manager, York Manufacturing Company, York, Pa., U. S. A.: ,Investigations as to the Efficiency of Ammonia Compressors when Running under Dry and Wet Conditions" Sickinger Dr., Chief Physician on the Military Staff, Vienna: ,The Application of Cold in Dentistry “ . . . . . . . . . Siebel Dr. J. E., Director of the Zymotechnic Institute, Chicago: , Superheated Vapors Employed in Refrigeration “ . . Simony Leopold, Architect, and Artmann Dr. techn. Emil, Professors at the Technical University in Vienna: *The Influence of Cold Upon the Construction of Building" Smith Dr. Edwin F., Pathologist, United States Depart- ment of Agriculture, Washington, D. C.: ,The Relation of Mikro-organisms to Low Temperatures" . Smoluchowsky Maryan v., Professor: ..The Warmth Conduction of Pulverous Bodies and a new System of Warmth. Isolation Based Thereon" . . . . . Soelling A., Commissioner to the Danish Government Fisheries Department, London: *An Improved Method of Packing Gutted Fish for Trans- port and Keeping it Fresh and Sweet for a Long Time" Spierer Ch. M. (Messrs. Fratelli Allatini, Salonicco): ,Cold and Moisture as Means of Preserving the Working Qualities of Tobacco Leaves“ . . . . . . . . . . . . . Stehlik Dr. Em, Councillor-Reporter: ,The Abattoirs and Markets of Prague“. . . . . . . . . Report Discussion 77 49 500 1123 91 52 182 64 40 187 408 676 515 292, 293 645–646 69 301–302 928—932 ^ *- 1159 Selefeld Richard, dipl. Engineer, Pankow-Berl in : , Refrigerated Railway Transportation" . . . & Suáreg Nicholas T., Head of the Sanitary Department of Refrigerating Plants at Buenos Ayres: ,The Sanitary Inspection of Refrigeration Plants in the Argentine“. . . . . . . . . . . . ... • . . * * * * * r Tassily E., Doctor of Science, Professor Agrégé at the Pharmaceutic School, Paris: , Use of Cold in the Pharmaceutic Products Industry" . . . . Tauss Hans, dipl. Chemist, J. R. Chief Inspector of Trade. Vienna: , Trade Laws and Regulations for Artifical Ice Manufactories and Refrigerating Plants of Cold Storage Houses in Austria" . . & * * * * * * * Tegetmayer Adolf, Chief Engineer at the Linde Ice Machine Company, Wiesbaden: ,Experiments on dry and wet Compressor Procedure of Condensing Cold Steam Machines" Tellier Ch., Paris: , Cold Without Fuel, and the Consequences" . Terry H. L., Engineer, Manchester: s , Applications of Cold in the India-Rubber-Industrie“ . . . Torrance Henry, Jr., M. E., Vice-Président Carbondale Machine Co., Carbondale, Pa., U. S. A. : Refrigeration and Ventilation of Inhabited Places". Vámos Eugen, District Veterinary and Reporter, Budapest: n.The Meat Problem and the Refrigerating Industry" Viny Dr. H, 2nd Class Chief Physician, Chief of the service of the 11th Cuirassier Regiment: , A Comparison of the Respective Values of Frozen and Chilled Meats, from the Point of View of General Provi- sioning and More Especially of Provisioning of the Army and Large Bodies" . . . . . * * * * Vries P. de, Professor at the Royal Academy of Horticulture (Holland): *Application of Artificial Cold in Plant Cultivation" Wagner Heinrich, Professor at the Technical University of Vienna, Chief Engineer for Naval Construction: »On Refrigerating Plants on Ships“ . . . . . . . Report Discussion 578 745 1078 106 33 763 839 356 329 854 897 1018 1132–1133 294 de * * 914—915 1160 ...” Wanjenbergh L. van, President of the Syndicate *Butchers' and Porkbutchers' Union of Bruxelles and Environs.<, Bruxelles: ,The Applicationg of Mechanical Refrigeration to the Preservation of Fresh and Salt Meat" . . . . . . . . . Weiser J., Director of the Petroleum Raffinery Gustav Oberleitner, Mähr-Schönberg: ,Processes for 'Obtaining Paraffin with the Aid of Artificial Cold “ . .# dº * & e º * e (* * tº. tº * * * * * * * * * * Wendrich Alfred de, Vice-President of the International Association of Refrigeration, Senator of the Russian Empire: nStatistics of Refrigerated Transportation" . . . . . . . . — — . The Feeding of the Nations“ . . . . . . . . . . . Whitten W. M., B. S., Pittsburg, Pa., U. S. A.: ;Several Methods of Testing Cold Storage Insulation, with Comparative Results" . . . . & © e º º e = Wood Harold B., Gifford-Wood Co., Hudson, N. Y., U. S. A.: , Handling Ice at Ice Plants and Car Icing Stations“ . . . You André, Director of the Colonial Office, Paris: Present Situation of the Refrigerating Industry in the French Colonies . . . . . . . . . . . . . . . . . . . . . . Report | Discussion 401 — 691 || 915–917 937 || 645 (664) 523 ||1060–1062 1067–1072 || 249 – 1033 || – |. 1099 1139 Andrault Artmann Babcock . Bail , Banfield . Barth Behm . Berencreutz Biquard . Bloch Bonjean . Bontoux . Borodine Bourgoin Boutaric . Bützler Index. A. Reporters. (Cf. moreover the ,, Alphabetic List of Reporters“ page 1149.) A. Page 119 64 430 . . 36 135, 865 461 . 194 . 1084 206 945 E. Eitner ê º º Elger von Elgenfeld Engelmann . Erban F. Favero Figdor Fleury Gasnier Gillmann . Gore Green . Grünzweig Gruvel Guerault , Guiselin Haas . Heimpel. Heiss , Hirsch |Holitsch . Huizer Jacquin . Jakowleff Jakowetz Jeancard Jumau Juppont . Page 766 123 886 774 860 219 975 º 257 º 144 381 260 221 1088 445 Cavalier . Čižek. Claude Corbett . Costa . Cramm Dennis Dennissoff Dohmann Drobniak Dupont . 542 . . . . . . . 703 . . . . . . . 267 802, 810 849 . . 339 545, 547 , 464 , 1086 490 872 74.1 . 677, 716, 718 , 1111 268 347 . 1095 ... 1044 590 816 273 495 742 . . 787 233, 282 1162 K. *\ Page Raiser . . . 412 Kamerlingh-Onnes 19, 1104 Rarcher 525 Kavan 735 FCerkhoven . 683 Kirchacker. 696 Rirsch 54 Koopman 834 Krupsky 996 L. Larsen ... 1042 Lebrou . 453 Tecomte 419 Lescardé 406 Liernur . 498 Linde . 11 Löhnis ... 550 Loinville tº a tº e 419 Lorenz (Danzig) . . . . , 128 Lorenz (Wien) , . . . 42 Loverdo . . . . . . . 1048, 1119 M. Mc Pike. ... 1003 Marshall , 386 Martel . 317 Masse 234 Matthews 145 Mertus . 528 Messner . . . 421 Metz . 194, 239 Monti 791, 796 Mori . 339 * N. Neff . , . . . 174 , Neuwirth . . 59 Nilsson . 283, 979 O. Orshover 487 Ottendahl 895 Ottmann . . . . . . . . 245 - P. Pennington 592 Perez . . 565 Planckh. 531 Poock. 673 Porges 685 Preissecker. 665 Przibram 38 Q. Page Quentin . . . . . . . . ... 1075 Query . . . . . . . . 46, 372 R. Rautenkrantz . tº tº . 84 Regen . . . . . . . . . 1107 Reidrer . . . . 782 Rittermann . • * . . 699 Roessingh . . . . . . . 1052 S. Sandras . . . . . . . . 901 Satie . . . . . . . . T. 742 Satkewitsch 77 Schiff . . . 49 Schwarz . 500, 1123 Shipley . 91 Sickinger #2 Siebel' 182. Simony * > 64 Smith 40 Smoluchowski. 187 Soelling . . 408 Spierer . . . . . , 676 Stehlík . . . . . . 515 Stetefeld ... 1018 Suárez 578 T. Tassily . . . . . . . 745 Tauss . . . . . . . . . . . . 1078 Tegetmeyer . . . . . , 105 Tellier . . . . . . . . . . 33 Terry . . . . . . 763 Torrance . . . . . . 839 V, Vámos . 356 Viry . . 329 Vries tº º º 854 W. Wagner . t 897. Wanjenbergh . . . 401 . Weiser . . . . . . . . 691 Wendrich . 523, 937 Whitten . . . . . . . . . . 249 Wood, . ... 1033 g Y. You . . 1099 1163 B. Commissions. * r Pages Adress Delivered, by the Geheimrat Prof. C. v. Zünde . . . . . . . . . . . . . 11 Commission I. Scientific. . . . . . . . . . . . . . . . . . . . . . . . . . . . 19–73 Experiments at the Cryogenic Laboratory at Leyden. By Prof. Dr. Kamerlingh-Onnes . 19 Cold Without Fuel, and the Consequences. By Ch. Tellier . . . . . . . . . . . . . 33 The Use of Cold in Bacteriological Examinations. By Prof. Dr. Oscar Bail . . . . . , 36 Artifical Production of Low Temperature in the Biologische Versuchsanstalt. By Dr. phil. *. Aſans. Przibram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38 The Relation of Micro-organisms to Low Temperatures. By Dr. Edwin F. Smith . . . . 40 The Application of Cold in Surgery. By Dr. Hans Zorenz . . . . . . . . . . . . . . 42 The Employement in Therapeutics of Liquid Air at — 180° C. By Dr. Z. C. Query . . 46 The Use of Cold in Dermatology. By Prof. Dr. Eduard Schiff . . . . . . . . . . . 49 The Application of Cold in Dentistry. By Oberstabsarzt Dr. Sickinger . . . . . . . . 52 Experiments on the Change of Hardening Processes of Hydraulic Binders at Low Temperatures. * By Bernhard Kºrsch . . . . . . . . . . . . . . . . . . . . . . . . . . . 54 Cold Destructive to Monuments. By Hofrat Prof. Dr. Yosef Neuwirth . . . . . . . . 59 The Influence of Cold upon the Construction of Building. By Zeopold Simony, Architekt and Dr. techn. Emil Artmann . . . . . . . . . . . . . . . . . . . . . . . 64 Report of Proceedings of Commissionn I. . . . . . . . . . . . . . . . . . . . . . 67 Commission II. Constructing, Operating and Testing Refrigerating Machinery and Insulating Material. . . . . . . . . . . . . . . . . . . . . . . . 77 314 What are we to Understand by the Term ,The Efficiency of a Refrigerating Machine?" By Alexander Satéezvätsch . . . . . . . . . . . . . . . . . . . . . . . . . 77 The Electrical Telegraphic Thermometer. By Ingenieur Yohannes Rautenkrantz . . . . 84 Investigations as to the Efficiency of Ammonia Compressors when Running under Dry and *: , Wet Conditions. By Thomas Shipley . . . . . . . . . . . . . . . . . . . . 91 Experiments on Dry and Wet Compressor Procedure of Condensing Cold Steam Machines. By Adolf Zegetmayer . . . . . . . . . . . . . . . . . . . . . . . . . . . 105 Investigations upon Refrigerators with Frosted Surfaces and Refrigerators with Wet Surfaces, their Advantages and Disadvantages. By Paul Andrault . . . . . . . . . . . . 119 The Working Pressures and Effects of Cold Air Turbo-engines. By Zd. Elger v. Elgenfeld 123 The Possibility of Employing Turbo-blowers as Colling-machine Condensers. By Ingenieur . Dr., Hans Zorenz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128 On the Manufacture of Crystal Ice from Exhaust Steam and the Practical Results obtained by this Process. By R. C. A. Banfield . . . . . . . . . . . . . . . . . . . 135 Arrangements and Safety Devices for Avoiding or Minimising the Damage done to Compressors -- , and Coils, especially in the Case of Excessive Pressure accidentally caused by Mistakes made in the Working of the Plant or from any other Cause. By G. Gillmann , 144 New Arrangements and Improvements in the Construction of Apparatuses for Refrigeration. Results of Experiments thereon. By F. E. Matthews . . . 145 Conditions, of Acceptance, Various Tests (Resistance, Stanchness, etc.) of the Materials and Parts entering into the Construction of Refrigerating Apparatuses. By Peter Neff . 174 Superheated Vapors, employed in Refrigeration. By Dr. J. E. Siebel . . . . . . . . . 182 The Warmth Conduction of Pulverous Bodies and a New System of Warmth Isolation based thereon. By Prof. Maryan v. Smoluchowská . . . . 187 New Apparatuses for Determining the Coefficients of the Conduction of Heat. By Friedr. Aud. Metz, and 4. Behm . . . . . . . . . . . . . . . . . . . . . . . . . The Efficiency of Various Methods of Insulating Refrigerated Rooms. By R. Biguard . 206. nzementholz" (Converted Wood) as Insulating Material. By Wilhelm Figdor . . . . 219 Cork as, an Insulator of Heat. By Max Grünzweig ... . . . . . . . . . . . . . . 221 1164 * - *s. Pages • The Cellular Calorifuge. By M. Fupport , , , . . . . . . . . . . . . . . . . . , 233. Insulating Materials. By M. Masse . . . . . . . . . . . . . . . . . . . . . . . . . 234 The Theoretic and Actual Insulating Value of Hollow Spaces. By Friedrich Rudolf Metz 239. Artpumice and Its Use as An Insulator. By Ingenieur Heinrich. Ottmann . . . . . . . 245 Several Methods of Testing Cold Storage Insulation, with Comparative Results. By W. M. Whitten 249 The Cooling of Electrical Machinery. By Paul Gasnier . . . . . . . . . . . . 257 New and Improved Arrangements in the Installation and Operation of Ice Factories. By van * Rensselaer H. Green . . . . . . . . . . . . . . . . . . . . . . . . . . . . 260 The Position of the Refrigeration Industry in Russia. By Mr. Wicolaus Borodine . . . . 267 The Technical Intervention of National Cold Societies in the Building and Management of Cold Plants. By Ingenieur Karl Heimpel . . . . . . . . . . . . . . . . . . 268 Concerning the Economies and Statistics of the Utilization of Heat in Mechanical Refrigeration. By Lieutenant Colonel D. Şakowleſ . . . . . . . . . . . . . . . . . . . 273 The Distribution of Electric Energy and the Application of Cold. By M. Wuppont . . . 282 Refrigeration in Sweden with Ice and Salt. By Lauritz Wilsson . . . . . . . . . . 283 Report of Proceedings of Commission II. . . . . . . . . . . . . . . . . . . .291 Commission III. Application of Refrigeration in the Food Industries. . . 317—662 The Respective Comparative Values of Frozen and Chilled Meat from the Point of View of General Consumption, and more particularly of the Provision of the Army, the Navy, and Public and Private Administrations. By H. Martel . . . . . . . . . . .317 A Comparison of the Respective Values of Frozen and Chilled Meats, from the Point of View of General Provisioning and more especially of Provisioning of the Army and Large Bodies. By Dr. H. Wºry . . . . . . . . . . . . . . . . . . . . . . 329 Investigations on the Preservation of Horseflesh by Means of Cold, and the Use of this Flesh for Food. By Dr. Alexander Costa and Dr. Wello Mori . . . . . . . . . 339 Cold Storages as Accumulators for the Provisioning of Armies in the Field. By H. Heiss 347 The Meat Problem and the Refrigerating Industry. By Eugen Vámos . . . . . . . . . .356 Changes in the Physical and Morphological Conditions of Food Stuffs (Meat, Fish and Milk) by Cold. By Dr. Bützler . . . . . . . . . . . . . . . . . . . . . 368 Changes, which may be induced by Cold in the Physical, Chemical, and Morphological Composition of Foodstuffs, especially Meat, Fish, Milk and its Products, Fruit etc. By Dr. Z. C. Query . . . . . . . . . . . . . . . . . . . . . . . . 87° The Effect of Low Temperatures on the Life Processes of Fruits and on the Rate of Fermen- tation of Cider. By H. C. Gore . . . . tº e º e º ſex º º e o 'º º e . . . . . 381 The Effect of Cold Storage upon Bacteriological and Chemical Changes in Milk and Butter. By Dr. Chas. E. Marsha/2 . . . . . . . . . . . . . . . . . . . . . . . . . 386 The Application of Mechanical Refrigeration to the Preservation of Fresh and Salt Meat. By Z. van Wanjenbergh . • * * * * * * * * * * * * * * * * * * * * . 401 The Preservation of Eggs by Refrigeration. By F. Lescardé . . . . . . . . . . . . . 406 An Improved Method of Packing Gutted Fish for Transport and Keeping it Fresh and Sweet for a Long Time. By 4. Sölling . . . . . . . . . . . tº e º 'º e º 'º e 408 Application of Cold in Public Dairy Management. By Franz 5. Kaiser . . . . . . . . 412 New Application of Refrigeration in the Preparation of Concentrated or Solid Foods, Especially Milk Powder. By F. G. Zecomte and R. Loinville . . . . 419 On the Importance of Refrigeration for Foods, with Special Consideration of Milk. By - Dr. Hans Messner . . . . . . . . . . . . . . . . . . . . . . . . . . 421 The Application of Low Temperatures to the Curing and Storage of Cheddar Cheese. By Dr. S. M. Babcock . . . . . . . . . . . . . . . . . . . . . . . . 430 The Use of Cold in Cheese-making. By Paul Guérault . . . . . . . . . . . . . . 445 The Application of Refrigeration in the Manufacture of Roquefort Cheeses at Aveyron, By P. Zeffrou . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 453 1165 A. • - Pages Application of Cold in Margarine Manufacture. By Ferdinand Barth . . . . . . . . . 461 The Precooling of Fruit in the United States. By S. 7. Dennis . . . . . . . . . . . 464 The Preservation of Fruits de Luxe. By H. van Orshover . . . . . . . . . . 487 Appropriate Refrigeration Plants in Modern Slaughter-Houses. By Mr. Dohmann . . . 490 Concerning the Management of Cold Storage Plants. By Prof. E. Yalowetz . . . . . . 495 Cold Storage for the Suburbs of Paris and the Provinces. By Mr. Francis Ziernur . . 498 The Application and Arrangement of Ozone Apparatuses in Cold-rooms. By Alois Schwarz 500 The Abattoirs and Markets of Prague. By M. Em. Stehlāk . . . . . . . . . . . . . . 515 The Refrigerating Installations of the City of Prague. By Zouis Čižek . . . . . . . . 518 The Feeding of the Nations. By A. de Wendrich . . . . . . . 523 The Application of Refrigeration in Breweries. By M. Aarcher. * * * * * * * 552 The Preservation of Hops after Removal from Cold Storage. By M. A. Mertus . . . . 528. Refrigerating by. Ventilation for Ferment Cellars and the Application of this System to 2. Other Cooled Rooms in Breweries. By Rudolf Planckh . . . . . . . . . . . 531 The Cooling of Water for Public Consumption. By M. Ed. Bonjean , . . . . . 542 Presence and Future of the Export of Butter meat, hogs etc. from Russia to Great Britain. . By Dr. Z. z. Cramm . . . . . . . . . . . . . . . . . . . . . . . . . . 545 Russia's Domestic and Export Trade in Perishable Produce During the last Decade. By , Dr. Z. E., v. Cramm. . . . . . . . . . . . . . . . . . . . . . . . . . 547 Import and Export of Meat in Various Countries and the Answer to the Question: Is the Import of. Frozen and Chilled meat from Abroad Desirable for the Netherlands? . By F. B. Löhnis and D. A. de jong . . * * * * * * ~ * tº a tº e s - 550 The Sanitary State of Argentine Cattle. By Dr. Ferdinando Perez , * . 565 The Sanitary Inspection of Refrigeration Plants in the Argentine. By Nicholas T. Suárez 578 Drinking Cups made of Ice. By H. D. P. Huizer . . . . . . . . . . . . . . 590 The Refrigeration of Poultry and Eggs in the United States. By Dr. M. F. Pennington . 592 Report of Proceedings of Commission III. . . . . . . . . . . . . . 633 Commission IV. Industrial Refrigeration . . . . . . . . . . . . . . . . 665–933 Concerning the Use of Low Temperatures in the Tobacco Industry. By Dr. Karl Preissecker 665 The Use of Refrigeration in Destroying Tobacco Worms. By Gustav Poock . . . . . . 673 Cold and Moisture as Means of Preserving the Working Qualities of Tobacco Leaves. By Ch. 44. Spierer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 676 The Use of Cold in the Petroleum Industry. By A. Guiselin . . . . . . . . . . . 677 Cold Technics in Connection with the Paraffin Industry in Holland and the Dutch Colonies. By E. S. Kerkhover . . . . . * * * * * • 683 On the Application of Artifical Cold in the Manufacture of Paraffin in Austria-Hungary. By Philipp Porges' . . . . . . . . . . . . . . . . . . . . . . . . . . 685 Processes for Obtaining Paraffin with the Aid of Artificial Cold. By 7. Weiser . . . . . . 691 Effect of Refrigeration on Mercerizing. By Dr. Armand Kirchacker . . . . . . . . . 696 The Application of Cold in the Próduction of Azote Dye-stuffs. By Daniel Rittermann 699 The Use of Cold in the Chemical and Physical Indusries. By A. Guiselin . . . . . . . 718 The Rational Use of the Absorption Refrigerating Machine in Chemical Industries. By - Dr. Kava” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 735 Application of Refrigeration to the Glue and Gelatine Industry. By Paul Cavalier . . . 738 Applications of Refrigeration to the Perfume Industry. By justin Dupont . . . . . . 741 The Applications of Refrigeration to the Raw Materials of the Perfumery Industry. By Pauz w jeancard and Conrad Satie . . . . . . - 742 Use of Cold in the Pharmaceutic Products Industry. By E. Tassilly . . . . . . . . . 745 * - The Application of Artificial Cold to the Rubber Industry. By 5. Boutaric . . . . . . 750 * Application of Cold in the ladia-Rubber-Industry. By H. Z. Zerry . . . . . . . . , 763 Application of Cold in the Leather Industry. By Wilhelm Etner . . . . . . . . . , 766 1166 Pages - Importance and Application of Low Temperatures in the Textile Industry. By Dr. Franz , Brºa” . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 774 An Application of Cold in Oil-gas Producer Plants. By 7. Reidrer . . . . . . . . . 782 . Application of Refrigeration to the Electric Accumulator Industry. By Z. Yumau . . . , 787 On the Influence of Recent Improvements in Heat and Refrigerating Machinery, and of the Progress Made in the Transmission of Energy, Upon the Cost of the Calorie and Frigorie Respectively, and Hence on the Advent of a System of Concentration of Solutions by Freezing, and by Condensation, in a Vacuum at a Low Temperature. By Dr. Eudo Monti . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 791 Changes in the Physical, Chemical and Organic Properties of Vegitable Extracts, Particularly *- Wine, Must and Fruit Juices, Caused by Permeating them with Air at a Low Temperature, and the Subsequent Release at Summer Temperature of the Air Thus Dissolved. By Dr. Eudo Mont: . . . . . . . . . . . . . . . . . . . . 796 Report on a Liquid Oxygen Life-saving Appliance and on Apparatuses for the Production 3. of Liquid Oxygen. By Georges Claude • . . . . . . . . . . . . . . 802 Report on the Recovery of the Vapours of Volatile Liquids by Refrigeration. By Georges Claude . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 810 Note on the Preservation of Dead bodies. Charles }acquin . . . . . . . . . . . . . 816 Cooling of Dwelling Apartments. By Mr. Bourgoin . . . . . . . . . . . . . . . . 818 The Cooling of Living and Other Rooms in the Tropics. By 5. F. H. Koopman . . . 834 Refrigeration and Ventilation of Inhabited Places. By Henry Torrance . . . . . . . 839 The Application of Refrigeration to the Retarding of Plants and the Perservation of Flowers. By Z. C. Corbett . . . . . . . . . . . . . . . . . . . . . . . . . . . . 849 Application of Artifical Cold in Plant Cultivation. By P. de Vries . . . . . . . . . . 855 The Application of Refrigeration to Silk-Worm Culture. By S. Primo Favero . . . . . 860 The Application of Mechanical Refrigeration to Blast Furnaces. By R. C. A. Banfield .. 865 Shaft Sinking by Freezing Process. By Franz Drobniak . . . . . . . . . . . . . . . 872 Arrangement and Management of Open Air Artifical Ice Rinks. By AEduard AEngelmann 886 The Use of Cold in the Manufacture of Explosives. By M. Ottendahl . . . . . . . . . 895 On Refrigerating Plants on Ships. By Heinrich Wagner . . . . . . . . . . . . . 897 The Ice Manufacture. By M. Sandras . . . . . . . . . . . . . . . . . . . . . . . .901 w e Report of Proceedings of Commission IV. . . . . . . . . . . . . . . . . . . . . . 911 S Commission V, Transportation . . . . . . . . . . . . . . . . . . . . . 937–1072 Statistics of Refrigerated transportation. By Alfred de Wendrich . . . . . . . . . . . 937 Programme of the Commission of Transportation. By Richard Bloch . . . . . . . . . 945 Refrigeration by Means of Ice without Machinery. By P. Fleury . . . . . . . . . . 975 Railway Refrigeration Cars. By Lauritz AVålsson . . . . . sº . 979 A Method of Reducing the Difference in Temperature which Governs the Operating Ex- penses of Refrigeration Cars. By M. A. Kroupsky . . . . . . . . . . 996 Transportation of Perishable Freight in America. By Eugene 7. McPike . . . . . . . . 1003 Refrigerated Railway Transportation. By Rich. Stetefeld. . . . . . . . . . . . 1018 Handling Ice at Ice Plants and Car Icing Stations. By Harold B. Wood . . . . . . . . 1033 Re-icing Refrigeration Cars. By Georg Larsen . . . . . . . . . . . . . . . . . . . . 1042. Beer Shipment by Rail. By Alois Holitsch . . . . . . . . . . . . . . . . . . . . . 1044 The Experimental Refrigerating Station at Chateaurenard. By 7. de Loverdo . . . . . 1048 Increase of Refrigerating Equipment of the Netherlands Railways since the First Inter- national Congress of Réfrigeration in Paris, 1908. By J. A. Roessingh van Iterson 1052 Report of Proceedings of Commission V. . . . . . . . . . . . . . . . . . . . . . 1067 1167 arº--, *, , , , , --> -- -- Pages £ommission VI, Legislation . . . . . . . . . . . . . . . . . . . . . 1075–1140 general Report. By Maurice Quentin . . . . . º . . 1075 Trade "Laws and Regulations for Artifical Ice Manufactories and Refrigerating Plants of t Cold Storage Houses in Austria. By Hans Tauss . . . . . . . . . . . . . . 1078 The Use of Refrigeration in Sweden. By A. de Berencreutz . . . . . . . . . . . . . 1084 The Present Status of the Refrigerating Industry in Russia. By Basil Elie Dennissoff 1086 The Refrigeration Industry in the French and Other Colonies on the West Coast of Africa. By 4. Gruve. . . . . . . . . . . . . . . . . . . . . . ... 1088 Data on the Soil, Climate, Ranches and Slaughter-houses in the Republic of Paraguay. By Zeo Hirsch . . . . . . * * * * * * * * tº gº ... 1095 Present. Situation of the Refrigerating Industry in the French Colonies. By André You . 1099 Second Rcport on the Application of Mechanical Refrigeration in the Netherlands. By - O. Kamerlingh-Onnes . . . . . . . • * * * * * * * * * * * . 1104 Insurance in Connection with the Cold Indnstry. By Emil Regen . . . . . . . . . . . 1107 Instruction in Cold Technics in Holland. By M. de Haas . . . . . . . . . . . . . . 1111 * se tº º jº * g te g † i.e. o tº sº tº sº * tº ſº gº a º e º a The Present Status of Instruction in Refrigeration. By de Zozerdo . . . . . . . . . 1119 The Organization of Refrigeration Societies. By Alois Schwarz . . . . . . . . . . . . . 1123 Report of Proceedings of Commission VI . . 1131 1141 Resolutions of the Commissions I–VI . . Alphabetic List of Reporters and Titles of Reports . . . . . . . . . . . . 1149 *** -º \ \ => | | | | | | | | | | | | | | | | | | | | | | | | | H EE | | | | | | | | | | | | | | | | | | | | | | | | | | | II* Internat. Congress of Refrigeration, Vienna 1910 | | | | | | | | | | | | | | | | | || | | || EE == EE == tº . == HE H| ENGLISH EDITION H |H| OF THE REPORTS Ei H AND PROCEEDINGS == I L. & ºf | | | | || tº | | | is ºf | | || | | | || == :: º, ſº | | || | flº H HE § { == H; lº | | | || . . . == HE HE -*. == H| Vienna 1911. - Edited by the HF ºr GENERALCOMMISSARIAT lºs H Printed by J. Weiner, furnisher of the I. 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