SPONS' ENCYCLOPEDIA INDUSTRIAL ARTS, MANUFACTURES, COMMERCIAL PRODUCTS. SPONS' ENCYCLOPEDIA INDUSTRIAL ARTS, MANUFACTURES, COMMERCIAL PRODUCTS. DIVISION II. CONTAINING BEVERAGES (continued}, BLACKING, BLACKS, BLEACHING POWDEE, BLEACHING, BOGWOOD, BONES, BOEAX, BROMINE, BROOM -CORN, BRUSHES, BUTTONS, CAMPHOR, CANDLES, CANE, CARAMEL, CARBON, CARBON BISULPHIDE, CATGUT, CELLULOID, CEMENTS, CHICORY, CHLORAL, CHLORINE, CHLOROMETRY, CLAYS, COAL-TAR PRODUCTS, COCOA, COFFEE, CORK, COTTON MANUFACTURES, &c. E. & F. N. SPON, 125 STRAND. SPON & CHAMBERLAIN, 12 CORTLANDT STREET. 1882. BEEE. 385 Some brewers admit the water into the mashing tun at a higher temperature than is necessary for the mash, allowing it to cool before the malt is put in. In other breweries, the malt and water are introduced together into a machined mash tun, the initial heat of the mash being much higher than that required for the operation, so as to compensate for the loss of heat communicated to the mash tun. But it is preferable first to heat the mash tun with water, and then to introduce the malt, because the loss of heat in this instance only accrues from the malt admixed, and the opera- tion can be conducted with greater certainty. Another plan extensively adopted is, to moisten the mult to be mashed with water at a low temperature, in sufficient quantity to cause the malt to swell, and then to add the remainder of the water at an increased temperature, necessary to impart the proper temperature for the mashing. The water added is generally at the temperature of 88 to 90 (lyO to 194 F.). This plan is stated to have two advantages : it lessens the tendency to set, and is very exhaustive of the extractive matter of the goods. It enables the diastase to act more freely upon the starch, because the larger part of the sugar is dissolved out during the first wetting, leaving the remaining constituents in a better condition for attack by the solution. With regard to this system, other authorities affirm that, because the diastase is very soluble, it is removed with the sugar and from direct action on the starch. Upon this consideration, as well as from others, the general defects of mashing as usually employed, in any system, have been summed up as follows : Inefficient extraction, portions of the gluten and starch of the grain becoming a gelatinous mass, which prevents, by forming an impermeable coating, the remaining constituents from being attacked. The starch remains unconverted into glucose in consequence of too low a temperature being employed in the operation. Donovan gives the following temperatures for mashing : For well-dried pale malt, the first mash water should not exceed 77 (170 F.) ; the second, 82 (180 F.); and the third, 85 (185 F.) ; assuming the temperature of the atmosphere not to exceed 10 (50 F.). Sullivan states that under his experiments 100 parts of starch wero transformed into 100 parts of sugar, but that this sugar was intermediate in molecular structure between grape sugar and starch, and he termed it maltase, as previously referred to. This sugar is white, soluble in water, but less soluble in alcohol than glucose. English mashing, which is an inftusion process, differs from the Continental, and distinctly from the Bavarian process, since the latter is a method of decoction. With the English process, the malt is first opened or cracked, and sometimes comes from the rollers not perfectly crushed ; on the Continent, the malt is more finely crushed. Formerly, the malt was allowed to fall into water that had been fifst placed in the mash tun, but in present practice the malt is brought into contact with hot water, at a temperature determined by the circumstances of the particular situation and arrangement of the brewery. The English process depends chiefly in the use of water at a tolerably high temperature, and its characteristic is a high initial temperature. The English brewer seeks to avoid having too much albuminous matter in solution ; whilst the German brewer endeavours to render the albumen as soluble as possible, because he has to make a beer intended to be kept only for a short time. In parts of Germany and Belgium, the English system of employing a high initial temperature is adopted, but with some modifications. The mash first of all is given a temperature of 38 to 49 (100 to 120 F.), and sometimes as high as 60 (140 F.). It is allowed to stand for a short time, and hot water is added to bring up the tem- perature to about 65 to 71 (150 to 160 F.), the wort being run off after sufficient infusion. A, higher temperature is sometimes employed, even boiling liquor being added in order to raise the mash to 77 (170 F.), when it is left to digest, until iodine water or an alcoholic solution gives no blue reaction. The infusion process, general on the Continent, differs therefore in starting with a lower temperature, and in attaining a higher temperature by successive additions of hot water. As an example of the process of decoction, the old Bavarian method may be cited ; and this consists in boiling the wort along with the grains. The malt after it is properly ground is thrown into cold water, and is allowed to remain therein for from one to three hours ; after this, hot water is added to raise the temperature of the mash to 35 to 38 (95 to 100 F.). After standing a short time, the tap is opened, and grains, meal, in fact the whole of the contents of the tun, run off into the boiler. This thick mash, termed " dickmaisch," is boiled vigorously for half an hour, and is then run back again into the mash tun, where it has a temperature of 49 to 52 (120 to 125 F.), and the infusion process is allowed to go on. A second thick mash is pumped up into the boiler, and boiled for half an hour ; it is then run into the mash tun, the temperature being raised in this manner to 63 (145 F.). After a little mashing, the contents of the tun are allowed to remain. The third mash, or " lautermaisch," is then run off, and is a tolerably clear mash unmixed with grains. This is boiled in a copper for about half an hour, when it is run into the mash tun, to raise the tempe- rature to 75 (165 F.). The contents of the tun are then tapped and sparged with cold water. In Belgium, where malt and raw wheat are used together, the process is first conducted according to the English infusion method, a portion of the thick mash being pumped into the boiler and' boiled. Although this boiling destroys the diastase, it thoroughly breaks up the integuments of 2 o 386 BEVERAGES. Albuminous bodies (insoluble) .. 10 '71 Ash .............. 2-50 Woody fibre, empyreumatic products, and the like 14-37 the malt, and in this way the starch is converted into a kind of starch paste ; when returned to the tun, this paste meets with the diastase remaining unconverted, and then very rapidly undergoes change into dextrine and sugar. From the nature of the German process, the wort is rich in dextrine and poor in sugar ; consequently when fermented it yields less alcohol. Graham bus experimented, for the purpose of answering the question, in what way can the practical brewer alter the ratio of dextrine to glucose ; to ascertain if it can be altered to any extent, and whether there is a limit to the action of the diastase on the starch. The experiments were confined to one malt, analysis of which gave Water 7'51 Glucose .. .. 5-48 Dextrine 8-82 Starch 48-77 Albuminous bodies, soluble .. .. 1*48 Cold Aqueous Extract. 15 minutes. Glucose 5-48 Dextrine 8'82 Alcoholic Extract. 80 per cent. Glucose TOO When this malt was treated with water there was obtained, after a period of fifteen minutes, 5 48 per cent, of sugar, and 8 82 per cent, of dextrine, or in an additional fifteen minutes, 17 14 of augar and 9 65 of dextrine. An almost identical solution was obtained with 50 per cent, of alcohol, and from this fact it was concluded that the particular sample of malt contained an amount of sugar equal to 5J per cent. The next point ascertained was the amount of action taking place at different temperatures in a given time ; and starting with cold water at 15 to 21 (60 to 70 F.) the liquor was raised to the temperature indicated in the following table, and continued for two hours : 50 per cent. 5'68 Glucose, per cent Dextrine and starch 38 (100 F.) 43 (110 F.) 49 (120 F.) 64 (130 F.) 60 (140 F.) 24-19 34-00 30-00 29-25 32-17 27-33 35-71 24-11 37-50 26-70 These results show that there is a gradual increase in the amount of sugar formed, and that at 60 (140 F.) the process instead of being gradual, suddenly increases in intensity, yielding a much greater amount of extract. Graham also has tested the validity of the assertion as to the German process, varying in the range of temperature of 74 to 75 (165 to 167 F.), being the most favourable for the conversion of starch and dextrine into sugar. The mashing heat was started on the principle of a low initial temperature, raised up in the first hour to 38 (100 F.). It was then kept for two hours at a tem- perature of 60 to 63 (140 to 145 F.), and was finally raised to 74 or 75 (165 or 167 F.). The following table shows the results : Two hours at Six hours at 74 to 75 (165 to 167 F.) 74 to 75 (166 to 167 F.) Weight of extract per cent 70-25 70-55 Draflf .. .. 21-58 .. .. . 20-71 Glucose Dextrine 39-06 27-36 Starch 62-52 41-67 25-00 Starch 62-51 These results show a considerably larger amount of extract than with cold water, very much higher even than in the English infusion process. By prolonging the period for the temperatures at a higher stage, the German brewer is correct in his idea of getting a larger amount of sugar, and it remained to be seen, as an interesting experiment, what an extreme temperature of 79 (175 F.) would affect. A sample of malt was taken, and heated gradually, during sixty minutes, from the cold up to 77 (170 F.). It was then kept at that exceedingly high temperature for two hours, and the amount of sugar formed and extract obtained, are as in the following table : Weight of extract, per cent. Draflf Glucose Dextrine 0) 69-70 23-51 32-10 (2) 69-10 23-35 32-05 BEER. 387 Graham considers that these experiments are conclusive as to the advantage of low initial tem- perature, and a high final temperature, and therefore experimented as to the best way to arrange the mashing temperatures. Malt was heated from the cold up to 29 (85 F.) for one hour, then from 29 to 60 (140 F.) for one hour, when it was kept for three hours at 60, and then boiled. In the second series of experiments the malt was raised during the first hour from the cold to t>0 , when it was allowed to remain for two hours, and then raised very rapidly to 79, when it was boiled. In the third experiment it was raised in the first hour to 60, maintained during the second at that temperature, and in the third hour raised to 79. (i) (2) (3) Weight of extract, per cent. .. 71 '50 .. .. 71 "06 .. .. 69-00 Draff .. 21-70 .. .. 22-35 .. .. 22-61 Glucose , .. 41 66) _.., 40-07 = g^ S5 \ = Starch Dextrine . 25 -09) 62 ' 59 36 "45 !'51 oo.^f 60-67 The first two series give practically the same results, but with rapid increase of temperature there was great reduction in the amount of extract, as well as in the ratio of the sugar to the dextrine. Graham considers these experiments to show that the more gradually the temperature is raised, the more complete is the extract, and the higher the sugar-forming ratio. In Graham's experiments, the starch was broken up, not according to Husculus' theory, but in the reverse ratio. There was a larger amount of sugar and a smaller increase of dextrine. Referring to the experiments on the English infusion process at 60, 33 '5 per cent, of glucose is formed. As the temperature increases so the amount of sugar decreases, until at 77 the decrease is very great. These experiments prove that the higher the initial temperature, the less active the diastase ; and the less extract in a given time, the less sugar is formed. By starting with a low initial temperature, and raising it in the course of an hour to the temperature indicated, main- taining that temperature for two hours, there is a gradual increment of sugar with a gradual incre- ment of total extract. Malt Infusion, Low Initial Temperature. 38 (100 F.) 43 (110 F.) 49 (120 F.) 64 (130 F.) 60 (140 F.) Su<*ar . .... 24'79 30 32-2 35-7 37-5 Dextrine 34-00 29-2 27-3 24-1 26-5 From this table, it will be seen that at 60 the percentage of glucose has risen to 37 -5 per cent., indicating that a low initial temperature is best for the solution of the diastase. But for a given time, the diastase, when dissolved, attacks the starch most vigorously at a temperature of about 60 to 63; and whilst this temperature is advantageous for the rapid conversion of starch into sugar and dextrine, experiments have shown that the temperature of 74 to 75 was best for rapid con- version of dextrine into sugar. Graham makes ti.e following deductions as to the practical bearings of these facts. Barley malt when well prepared contains an amount of albuminous substances, or diastase, pro- duced in the germination process, greater than is needed for the conversion of starch found in the malt. Time is an important element in the changes produced, and the longer the time at a low temperature, the more diastase is dissolved, and therefore in subsequent stages, the more starch converted and sugar formed. The action of the diastase initially, when the mass of the diastase is small compared with that of the starch, is to form dextrine into sugar in the ratio of 2 to 1. In malt, however, there is so large an amount of diastase, that even in a short digestion an amount of sugar is obtained greater than in this ratio. In the English infusion process with its initial tem- perature varying between 60 and 68 (155 F.), but generally no higher than 66 (150 F.), there is an equal ratio of glucose and dextrine ; and this has been determined from worts obtained from four large breweries in different parts of England. As the initial temperature was raised above 66, the total extract decreased, as well as the rat : o of sugar to dextrine ; and when the initial tem- perature was decreased below 66, within certain limits, the total extract increased, as well as the ratio of sugar produced. The limits of these varying ratios cannot exceed two of dextrine to one of sugar, or two of sugar to one of dextrine, and the ratios produced in any given time, in any particular mashing trial, depend on the varying conditions of the experiments ; upon the relative masses of starch and diastase ; upon the temperature ; and on the quantity of water. It has been well authenticated that from 100 parts of starch not more than two- thirds can be obtained as sugar by the action of diastase: and this deficit is accounted for by Sullivan, who has proved the formation of maltase. as previously referred to. Maltase has a peculiar action on Fehling's copper solution, by which this test solution represents only an amount of reduction equal to two-thirds of that which 2 c 2 388 BEVERAGES. would occur if 100 parts of glucose were taken. Maltese formed iu the mashing process, breaks up under the action of the potash and the copper solution into two parts of glucose and one of dextrine. In the ordinary mashing process, there occur, it would appear from this consideration, two parts of dextrine and one of sugar ; and as the process continues, the ratio becomes more nearly equal, and is reversed by the application of more heat and long-continued action, practically illustrating the fact that the brewer may within certain limits vary the ratio of dextrine to sugar at will. In order to increase the ratio of the sugar, the brewer may start with a low initial temperature, and secure the solution of a large amount of the active principle of diastase. This solution obtained, the temperature of the mash may be raised to 60 to 65 (140 to 150 F.), either by adding hot piece liquor, or by steam driven under the false bottom of the mash tun, or by means of a heated coil, or by causing the wort to circulate through coils of pipes, delivering it finally to the top of the goods. After digestion for a certain period at this temperature, the mash should be raised to 74 (165 F.), because at that temperature more sugar can be produced than at 63 (145 F.), and because the higher temperature gives the additional advantage of a high tap heat. Upon the present plan of high initial temperatures, the brewer can increase the ratio of sugar by simply adding it. Cane sugar may be employed, and this can be converted into glucose by the action of the diastase, if added in the mash tun, or it can be converted partly into diastase by the action of the acids of the wort, by making the addition when the wort is boiled. If the cane sugar were to be added, without previous conversion, to the fermenting tun, it would require more yeast than glucose, because the yeast would have to do a greater amount of work, to break down the complex structure of the cane sugar to the more simple one of glucose. Cane sugars are dangerous, however, because they contain large amounts of albuminous substances likely to putrify, and it is preferable to convert the cane sugar into invert sugar. Invert sugar is the sugar produced by the action of acids on cane sugar, dextro-glucose, and Isevo-glucose. As glucose sugar can be made, not only from cane sugar, but from starch, there is nothing to prevent the brewer preparing his own grape sugar from starch, by treating this with dilute sulphuric acid and afterwards destroying the acid by means of chalk. Although the process may leave about one-half per cent. of gypsum in the sugar, this is an advantage in the fermenting tun, rather than a disadvantage. A variety of plans may be employed for increasing the quantity of dextrine. Dextrine when in large quantities, after the worts are fermented, gives what is termed roundness of flavour to the beer, and is therefore preferable for porter, stout, and the heavier class of ales. The dextrine of the wort may be increased by modifying the Bavarian method. Or the diastase may be rendered inert by infusing at 38 to 49 (100 to 120 F.), raising the temperature to 60 (140 F.), with tolerable rapidity, and when the infusion is complete at that temperature, again increasing to 79 (175 F.), allowing digestion to go on at that temperature. Another plan is to add unmalted grain, barley, or maize, but in this case the unrnalted grain should be kiln-dried at a temperature of 100 to 110 (212 to 230 F.), in order to render the albuminous matters less soluble, to decom- pose them in the presence of the moisture of the grain, to produce empyreumatic matters, and to obtain colouring products. Practically this treatment yields a malt not containing diastase. Having considered the theoretical principles of mashing, as well as having described the most approved processes, it may be advantageous to deal shortly with the latter, from a more practical point of view. The practical brewer should regard mashing as a triple, rather than a single process ; and should feel assured there is nothing to prevent the obtaining of good beer, when proper heats are taken. Like the extraction of the juices of meat in the making of soups, the extraction of the albumen from the malt depends upon the non-coagulation of the albumen at the commencement of the mashing. In the most approved practice, it is generally agreed that the heat of a pale beer mash, when all the malt and water are put in and finally mixed, ought to be 71 (160 F.). It is at this heat of the first mash that the best flavoured extract is produced, and the entirely chemical action of saccharification occurs. But this temperature must be gradually approached, because its sudden application would coagulate the albumen of the malt. The triple nature of the mashing process may be practically regarded as consisting in saturating, sacchari- fying, and extracting, to pievent setting or coagulation. The malt should be wetted at a heat that would give in the mash tun 64 to 66 (148 to 152 F.), or several degrees below the.best saccharifying point. When goods are thoroughly wet, water is applied at a higher suitable heat, with the internal rakes of the mash tun revolving, until the goods are at the temperature of saccharification ; after four or five hours' continuance of the saccharifying heat, the temperature should be reduced to that at which the brew began. Mashing, as performed in Steel's or other saturator, may commence at 64 for light, and 66 for heavy beers ; this means mixing about 1| barrel of water to the quarter of malt, and finishing with a firkin to a kilderkin, to a quarter, more of water at 87 to 90 (190 to 195 F.). The copper heats for the water employed will average about 77 (170 F.). A plentiful supply of cold water should adjoin the hot-water pipe, to secure regulating power BEEE. 389 When the mixture is in the mash tun in a saturated condition, the copper water, at 87 to 90 (190 to 195 F.), should be let in without delay, and the rakes kept going, until the goods are uniformly heated to 68 (156 F.). These heats are for perfect malt. For imperfect malt, or half barley, lower saturating heats may be used advantageously, but imperfect malts should never be used for fine beers, as neither a sufficient nor economical extract, nor good flavour can be obtained in the mash tun. The preceding observations refer to the first mash. The draining and extracting of the goods ought to proceed within two hours from the completion of the mashing operation. The mash should not be tapped through one cock, but should be drained through three or more, placed in the bottom of the mash tun. Draining should at first proceed slowly, until sufficient grains have settled around the cocks to act as a filter, which occurs in about twenty minutes. If the extract is to be completed by repeated mashings, the cocks, after the first mash is run off, should be closed, and the mash tun recharged with hot water, in such quantity as to make up the second mash of the brew, at a goods' heat of about the same as the first mash. The first mash ought to lie about an hour, and when run off, the third mash, if required, should be made up for a temperature with the goods of 66 (150 F.), and this mash should lie for half or three quarters of an hour only. The copper-water heats, and quantities of water required for these two after mashes are only to be obtained from actual experience with the particular plant. The second mash water will require to be about 79 (175 F.), and the third about 74 (165 F.), for mashes of ordinary quantities. This process gives roughly a three-mash brew. As it is difficult for the brewer to calculate these quantities accurately, it is preferable to keep the mash waters short of the quantities required, and to sparge at the end, with tepid water, to make up the copper charge. Another plan approved of by many brewers, is to make two mashes of reasonable thickness, and sparge up the remainder of t lie charge. In this cnse the sparge water ought to be of such a temperature as would allow the heat of the goods to fall to 66 (150 F.). In that known as the Edinburgh mode of mashing, all the water required is sparged on after the first mash. By this method, as soon as the taps have become fine, sparging is commenced, and tapping and sparging go on simultaneously until the extraction is complete. In working this system, the error is commonly made of putting on the sparging water too hot, even at a tempera- ture of 82 to 88 (180 to 190 F.). The first sparge heat should not exceed 77 (170 F.), and if the temperature of the mash exceeds 68 (156 F.), the sparge water may be at only 71 (160 F.). The tun covers should be removed whilst sparging is proceeding ; and water should not lie on the top of the goods whilst sparging, which always occurs if the mash has been too hot, or the sparge water added at too high a temperature. The water remains on the surface of the goods in conse- quence of coagulation having commenced, and the temperature of the sparge water should be at once lowered, and the taps closed for a short time. When the temperatures have been properly adjusted, the goods freely rise from the bottom of the mash tun and float, and allow the extracting liquor to readily percolate. This is an important point, and the goods should be kept up at least 6 inches from the bottom of the tun until the end of the sparging. As small brews must have the same time to extract as large brews, the runnings must of course be smaller in quantity ; and for this reasou the sparge water must be hotter than with large brewings, where the running off is performed so much more quickly. The small quantity of water falling from the sparger will cool more quickly than the larger quantity falling through the same space. After a mash has been maintained with the sparger at the temperature of 68 (156 F.) for about two and a half hours, the heat of the water should be suddenly lowered 12 or 15, so as to reduce the action of heat upon the goods to 66 (150 F.) towards the end of the sparging and running. In making strong beer, the necessity for strength will have required the running to have been stopped within two and a half hours, before the reduction of temperature, so that the effect of this reduction will be felt on the afterwort only, which may be table beer. If it is required to pump the tail ends of one mash over for the sparge liquor of another, all that is neteessary to ensure success is that the tail goods come off one mash at 63 to 66 (145 to 150 F.), and are re- heated by a steam coil, attached to the pump, to the necessary sparge hi at of 77 (170 F.), or that producing 68 (156' F.) in the mash. Tap heats afford no safe guide to the brewer, for the almost obvious reason that these do not truly represent the temperature of the mash, In the best practice in porter brewing, the temperatures of the mash do not differ much from those given for ale. Saturation should take place at about 1 lower, the temperature for the mash being ultimately the same as for beer, or 68. The peculiarly dry, sub-acid flavour, common to Irish porters, is the result of too great range of mash heats, by beginning at too low and finishing at too high a temperature, thus twice submitting the mash to the chances of acidity. Porter is best made from malt two-thirds of which is well-dried pale, and the remainder high amber and black. Eoasted malt should be used to the extent of 1 bushel to every 5 or 6 barrels of finished beer. Brown or blown malts are a mere waste of grain, will not keep, and yield little extract. The roasted malt is generally put iuto the mash tun amongst the -jther malts, but sometimes it is put 390 BEVERAGES. into the wort copper and boiled with the hop. An alternative method of great profit to the brewer on the large scale, is to mash the roasted malt by itself in a small tun fitted with a rake and false bottom, and an inner perforated concentric diaphragm through which to drain off the black extract. The washing out is performed with the extract from the large mash tun. Before proceeding to the description of the apparatus used in mashing, it will be convenient to describe the operation of sparging, as the mechanism employed in both cases can then bo classed, as they are used, together. Sparging is the process of extracting the remaining wort, which adheres to the insoluble draff or grains. The sparging is carried out by means of hot water, and if the wort has been run off at a temperature of about 63 to 66 (145 to 150 F.), the sparging liquid, as has been stated, should not be used above 77 (170 F.). This process goes on in different breweries to different extents, sometimes it is carried to such an extent that the wort obtained is excessively weak, containing only some 4 to 6 Ib. a barrel. This is not uaedt a once for the production of beer, as a rule ; it is not mixed with the previous wort, but is pnmped up into the copper and there used for the subsequent wort. This return wort, as it is called, is exceedingly liable to undergo decomposition, by which acidity, mainly due to lactic acid, but probably to other acids as well, is produced. In order to prevent the return wort from becoming acid, it is found convenient to keep it at a temperature of at least 88 (190 F.), and from time to time to add a little bisulphite of lime. Throughout the whole of the period, whether during the night or during the day, until tlie next time of use, the return wort must be kept at least as high as 88, for if allowed to fall to 66, acidification is very liable to set in. The wort resulting contains not only sugar and dextrine, but also an amount of albuminous matter ; this amount depends upon two or three conditions, and chiefly upon the nature of the barley originally employed. For instance, if the barley came from the North of England or Scotland, or if it had been growing on heavy land, it would contain much more albuminous matter, than barley grown on a light warm soil. And brewers occasionally make an error in judging of the strength of the wort, by merely depending on the use of the saccharometer, because the soluble albuminous matter sustains flota- tion of the instrument as well as sugar and dextrine. The amount of albuminous matter in the wort also depends on the previous malting process ; lastly, it depends on the nature of the water employed. The process of mashing having been described, the apparatus employed must be considered. A mash tun in its simplest form is a vessel of convenient size and shape, in which the malt and water can be mixed together, and from which the wort can be drained off. Mash tuns are usually made of wood, but cast-iron tuns are rapidly extending in use. A mash tun should have a capacity of from three to four barrels of malt, at least. Cast-iron mash tuns are constructed in segments bolted together, the connecting flanges being planed and truly fitted, or rust-joints being used. The bottoms of such tuns are usually formed of segments around a central casting, having as many sides as there are segments. It is necessary to case these metallic tuns in order to prevent too rapid radiation of heat; and the smaller the mash tun, the greater is the necessity for this protection, because the area of exposed surface is in greater proportion to the contents than with tuns of more considerable capacity. To enable the worts to be drained from the goods, mash tuns are made with perforated false bottoms, placed at a short space above the bottoms of the tuns. These false bottoms are made of wood, of cast iron, galvanized sheet iron, or of copper. When wooden false bottoms are used, the holes in them should be burnt, not bored, so that they may not be liable to close up by the swelling of the wood when damp, and they should be well countersunk on the under side. The cast-iron false bottoms are also countersunk on the under side, the countersinks being cast in the plate, whilst the holes are drilled or punched. The removal of the worts is effected at four or more points independently, so that in the event of the wort drawn from one portion of the tun not being clear, the tap communicating with it can be shut off. Another plan for attaining this end, is by an arrangement of mash-tun bottom, of which Fig. 302 is a section. The peculiarity in this form of mash-tun bottom is that the wort is drawn off from a number of points, at one and the same time, through a series of radiating tubes, H, of various lengths. The pipes H communicate with a central chamber, fitted with a removable top. The space below the false bottom with which the pipes H communicate is divided into compart- ments by the strips D, on which the false bottom rests, and the whole apparatus is constructed so that it can be readily removed from the mash tun for cleansing purposes. The pipes F and I serve for the removal of the wort, regulated by the cocks J. Mash-tun covers vary greatly in construction and efficiency, and in some instances, as in the case of the mash tuns used for porter brewing at the City of London Brewery, they are dispensed with ; this, however, is an objectionable practice, particularly in the case of large mash tuns. The simplest form of cover is a plain wooden disc, fixed a short distance above the mash tun ; the space between the disc and the tun itself being closed by sacking whilst the mash is being made. Mash-tun covers of this kind are used at Reid's and other breweries. At Mann, Grossman, and Paulin's brewery flat wooden covers are used, but are suspended so that they can be lowered to the mash tuns. BEER. 391 Another form of wooden mash tun cover is adopted in Allsopp's brewery. In this instance the mash tuns are covered by a permanent wooden roof, carried by a framework extending above the sides of the mash tun, and this frame is fitted with sliding shutters. Another plan is to form the cover of wooden segments of convenient size, applicable to maah tuns of moderate dimensions. At Hoare's brewery there is a very large cast-iron mash tun, capable of mashing 190 qrs., fitted with a dome-shaped cast-iron cover ; the central portion is fixed whilst the curved rim is formed of a number of flaps hinged to the centre. At Truman's brewery, the covers are formed of sheet copper, stiffened by brass ribs of "]" section. Each cover is in two parts, the central part carried by suspension rods at a fixed height above the tun, and the outer part, hung from chains which pass over pulleys, and provided with balance weights, so that this part of the cover can be raised and lowered. The junction between the two parts of each cover is formed with a projecting flange, which bears upon a ring of indiarubber carried by a corresponding flange on the central part of the cover. Before the introduction of machinery, the malt and liquor were mixed in the mash tun with oars, or wooden stirring-rods, and this method is still adopted in very small breweries. Where larger mash tuns are employed, such a method of mashing would not only be too laborious, but would produce most unsatisfactory results. The appliances most desirable for mashing are those best effecting the thorough mixing of the hull and flour of the crushed malt with the liquor, and leaving the goods in a porous condition, so as to be readily penetrated by any further amount of liquor. One of the earliest mashing machines, still in use in many old breweries, consists of a radial frame, which travels round in the mash tun. This frame has two horizontal shafts, one above and slightly in advance of the other. Each shaft carries a number of chain wheels, and over tliese work chains fitted with transverse teeth or rakes. As the shafts revolve, the teeth on the chains are drawn up through the goods, all parts of the latter being successively acted on as the frame carrying the shafts travels round the tun. At Barclay's, all the mash tuns but one are fitted with chain rakes of this kind, and they are also in use at Reid's and other London breweries. At Barclay's, the chains are now made of malleable cast iron. At Reid's, where there are four mash tuns, each capable of mashing 160 qrs., the mashing machine in each tun is double, or instead of the frame carrying the chain wheel shafts being merely a radius of the tun, it extends across the whole diameter. By this arrangement the goods are turned over twice during each revolution made by the frame, and the mixing is thus effected more quickly. In slow gear, the frame makes a complete revolution in fifteen minutes, whilst in quick gear it completes the circuit in ten minutes, the speed being equivalent to one revolution in five minutes with a single machine. In Reid's machines, the rake chains are of wrought iron throughout. An improvement on the chain rakes is the so-called porcupine machinery, which has perhaps been more extensively adopted than any other form of mashing apparatus. This mashing apparatus consists of a series of rakes carried by curved arms fixed to a pair of horizontal shafts, placed one above the other ; the rakes being arranged so that as the shafts revolve they pass each other, and thoroughly turn over the goods in the mash tun. The inner ends of the horizontal shafts are carried by plummer blocks attached to brackets, which encircle the central vertical or driving shaft, the lower end of which rests upon a suitable bearing at the bottom of the mash tun. The outer ends of the rake shafts rest in bearings carried by a kind of frame, which is connected by tie bars with the brackets encircling the central shaft, and supported by a pair of rollers bearing on the rim of the mash tun. Each shaft carries a sliding clutch for connecting it to its pinion, and these clutches are both worked by one lever, so that they cannot be engaged simultaneously. One of the pinion shafts extends inwards towards the centre of the mash tun, and at its inner end carries a bevel wheel, which gears into a bevel pinion on the central shaft, this pinion being about one-third 392 BEVERAGES. the size of the wheel. The rake shafts also carry bevel wheels, which gear into equal sized-wheels on the vertical shaft, the pairs of wheels being arranged so that the two rake shafts are both caused to revolve in the same direction. From the vertical shaft, motion is communicated to the rake shafts, and a slower motion to one of the shafts carrying a pinion gearing into the circular rack. From this shaft a still lower motion is communicated to the other shaft. When one of the rack pinions is thrown into gear with its shaft by means of its clutch, the whole apparatus will be made to travel slowly round the mash tun, and the rakes will be brought to bear upon the whole of the goods. The direction of motion of the apparatus, and the speed at svhich it is caused to travel, will depend upon which pinion is thrown into gear. This arrangement of travelling gear is similar to that adopted with chain rakes. The mashing apparatus here described has been very largely adopted ; it is in some breweries used alone, and in others with a separate mashing machine, such as Steel's. In most cases the arms and teeth are of wrought iron, but the teeth are sometimes of wood, and occasionally both the teeth and arms are wood. At the City of London Brewery, where mashing machines of this kind are in use, the central shafts are fitted with teeth, which act upon the central portion of the goods not touched by the revolving rakes ; and at Charringtou's brewery, where there are three mash tuns 18 ft. in diameter, and capable of mashing 100 qrs. each, these porcupine machines are also used, the rake shaft being made to extend across the diameter of the tuns. Another arrangement for stirring the goods within the tun, consists of a central shaft carrying two curved arms, which work close to the false bottom of the mash tun, and act upon the lower portion of the goods only. The mixing of the malt and water is effected by a Steel's masher before the goods enter the tun. Brewers are now of opinion that It ia better to effect the mixture of the malt and liquor in detail as these enter the mash tun, than- to deal with the goods in a mass. Separate mashing machines have consequently been adopted. The masher designed by Steel, of Glasgow, has probably been more extensively used than any other. This masher is of exceedingly simple construction. It consists merely of a cylindrical casing, within which revolves a shaft provided with a number of radial arms. The casing is open at one end and closed at the other, the shaft passing through a stuffing-box at this closed end, and provided outside with fast and loose belt pulleys. The grist and liquor are admitted to the casing by branches at the closed end, and as they pass through to be delivered into the mash tun from the open end of the casing, they are thoroughly mixed together by the action of the arms on the revolving shaft. The branch through which the malt enters is fitted with a regulating slide, and both the main casing and branch are fitted with hand holes which give access for cleaning. The water branch communicates with the side of the casing, and is fitted with a cock. In some mashers, there is no slide for regulating the supply of the malt, the latter being received direct from a small hopper placed below the malt mill. The casing of the masher, instead of being cylindrical, tapers slightly in its diameter, being reduced towards the end from which goods are delivered into the mash tun ; and to further delay the progress of the mash through the machine, the central shaft is fitted at intervals with flat arms, or oars, in addition to the usual circular arms. The liquor is delivered into the casing from the branch through two openings opposite each other, these openings communicating with a passage cast around the branch. Arrangements are made for admitting either hot or cold water through the openings. The central shaft of the masher is driven by bevel gearing. In numerous breweries, Steel's mashers are used alone, and the whole of the mashing is effected by them ; in other cases they are used in combination with larger mashing apparatus placed in the mash tun. Where separate mashers are alone employed, it is the practice to make but one mash, and to sparge the remainder of the length of liquor; where mashing appliances are provided within the tun, a series of mashes may be made, the goods being turned over during each mash. To ensure a steady supply of malt to the mashing machine, and to prevent balling, a malt feeder has been designed. This feeder is placed between the grist shoot and the mashing machine. It consists of a casing containing a drum, which has an oscillating motion imparted to it by an eccentric fixed on the central shaft of the mashing machine. On each side of the oscillat- ing drum are flaps, the position of which regulates the quantity of malt passing through ; thn drum, as it oscillates, leaving an opening between it and e;tch flap alternately. Fig. 3()i{ illustrates Steel's masher as arranged for pale and black malt mashing combined. F is the ground-malt hopper ; E, the outer masher or saturator ; D, the mash tun, with its revolving rakes arranged as previously described ; B, the pipe conveying the wort from the mash tun through the infuser; H, the black malt infuser and rakes; o the pipe from the infuser to the copper, where porter is being made. When the large mash tun D is charged with pale and brown malts, the proportion of black malt required for the brew is mixed with water in the small mash tun H. termed the infuser, at a temperature equal to that of the goods in D. The infusion of the black malt depends on the time of infusion of the other malts ; when these are infused sufficiently, and ready to be run off. the tap in the pipe C is opened as well as that in the pipe communicating between D and H. The half-pale extract from the large tun D is used to dissolve, absorb, and BEER. 393 carry off the colouring matter from the black malt in H. This plan has been found economical and certain, as it gives all the colour that can be obtained by mixing the pale, brown, and black inalts together, in addition to the quantity lost in dyeing the grains. The pule and brown grains becoming whiter by this mashing, are worth more in the market. The only uncertainty that can arise is from the wort losing heat, and this can be prevented by steam jacketing the pale and brown wort pipes. Another masher (Fig. 304) designed by Sorrell, and extensively used, consists of a casting forming three cylindrical chambers connected by intermediate passages, about 8 in. in length. Each chamber is fitted with a shaft, carrying a number of pins. These pins extend across the chamber, and are arranged so that all parts of the chamber are subject to their action. The three shafts each carry a bevel wheel at one end, gearing into three level wheels on a longitudinal shaft, carried by brackets on one side of the machine. The bevel wheels arc arranged so that the shaft in the central chamber is driven in the opposite direction to that of the other two. The shafts are driven at a speed of about 200 revolutions a minute. The first chamber, to the left in the figure, is constructed with a vertical neck, which is attached to the ground-m.ilt hopper or grist case; and in the neck there is a feed-roll, B, which regulates the supply of malt to the masher. The feed-roll is driven by a belt from a pulley on the stirring-shaft passing through the first chamber. Below the feed-roll there is fixed to the outside of the neck the water-box C ; this box is supplied with liquor from the copper, and communicates with the interior of the machine through holes in the casting. Another water-box, H, is also fixed on the neck between the second and third chambers to receive water of a higher temperature. 394 BEVERAGES. The operation of working this masher is as follows: The cock communicating with the water- box C having been opened, and a supply of liquor at the temperature of 76 (168 F.), admitted, the motion is communicated to the shafts, when the malt, as it falls from the feed-roll, is met by liquor entering through the holes in the casting. Any liquor not absorbed by the falling malt is received in the first chamber, where it is thoroughly mixed with the partially wetted malt by the action of the pins on the agitating shaft. From the first, the partially formed mash is passed on to the second chamber, traversing on its way the intermediate neck. These intermediate necks are an important feature in the machine, as the malt during its passage has time to absorb the liquor. In the second chamber, the mashing process is repeated, and the mash is then passed on through the neck between the central and third chambers, where it is met by a secoud quantity of liquor admitted through a number of holes communicating with the water-box H. This second supply of liquor is at a higher temperature than the first, the malt having been prepared, by the stiff mashing it has already undergone, to receive a higher heat. The mixture of the second supply of liquor with the malt is completed in the third chamber, and from this the mash is delivered into the mash tun, where it remains from one and a half to two hours. Sparging can then be com- menced, and continued until the required length has been run over. Another mashing machine, designed by R. Wilson, of Alloa, differs from those described in being self-acting. It is driven not by power externally applied, but by the action of the malt and water. This masher, Fig. 305, is attached by the flange N to the spout leading from the grist-case, and the admission of the ground malt is regulated by the valve G, the spindle of which carries a lever handle fitted to a catch. The malt, as it falls, has to pass through a thin sheet of hot liquor which issues from the pipe E, the opening of this pipe being fitted with a sluice F, by which the quantity of liquor admitted can be regulated. Passing on, the malt and liquor full into the buckets of the breaker wheel D, and cause the latter to revolve at a high speed. The buckets of the breaker wheel are of V form, and by their action and that of knives between which they work, the mash is mixed as it passes to the lower part of the machine. The spindle of the breaker wheel passes through the sides of the machine, and carries at one end the fly-wheel, which tends to equalize the motion, and also serves as a hand-wheel when neces- sary. The mash is deliver, d into the mash tun through the nozzle P, this nozzle being fitted with a serrated balance plate H, hinged at its upper side, and working over the discharging mash, levelling it, and preventing it from splashing into the mash tun. It is desirable to have the contents of a mash tun at all times completely under control, and several arrangements are employed for this purpose. Beneath the false bottom of the mash tun there is sometimes placed a pipe, coiled spirally. Into this pipe, steam can be admitted and the temperature of the mash increased, the action of an arm working above the false bottom tending to some extent to equalize the temperature in the different parts of the tun. This arrange- ment is simple, but it is scarcely applicable for ordinary use, as the increase of temperature is not sufficiently uniform in all parts of the mash. A more suitable apparatus for controlling the heat of the mash is the mash tun attemperator, designed by J. Crockfoid. The attemperator, Fig. 306, is shown as fixed to a wooden mash-tun with sliding doors and fixed roof, as used in the Burton breweries. It consists of a circular cistern, fixed on the top of the mash tun, and containing a coiled steam pipe. When it is desired to raise the temperature of the mash, the wort is drawn from the tun by the pipe A, and the centrifugal pump B is set in action, the wort being raised into the attemperator through the pipe C. There it is heated by the action of the steam in the coiled pipes, and is then led down through the pipe E to the central vessel of the spurger J, which distributes it over the goods. The pipe C conducts the wort to the bottom of the attemperator, whilst the pipe E draws off the wort from near the surface, where it has greatest heat. The central pipe in the attemperator is for admitting the ordinary supply of hot liquor to the sparger. So long as tiie pump B is in action, a constant current is maintained through the goods, the wort being drawn off at the bottom, heated, and again sparged on the top continuously. By the use of the attemperator, the temperature of the mash can be maintained for any period ; and in the case of small brewings, where the loss of heat from radiation is proportionately very great, the apparatus is particularly valuable. It is the custom to complete the length, or total quantity, of a brewing by distributing over the goods the required amount of liquor by the aid of a sparger. A sparger in its usual form consists of two or more tubular radial arms, perforated on one side, and leading from a central cistern. These arms are mounted to revolve freely over the goods in the mash tun. In some cases, the BEER. 395 cistern rests upon a point, and in others it is carried by friction wheels. When the mash tun contains mashing apparatus driven from the central shaft, the cistern of the sparger is made annular to surround the shaft. The shaft carries a disc, on which run the friction wheels of the sparger ; in many instances the bevel wheel on the shaft serves as brace for the friction wheel. The cistern is in most cases open at the top, the liquor being delivered into it by a pipe conveniently placed ; but 306. in some instances the vessel is connected to the supply pipe by a joint, so that the water may be delivered under pressure, the joint being formed so as not to interfere with the reaction of the sparger. Spargers are chiefly driven by reaction, the water issuing from the perforations of the arms, im- parting motion to them on the principle of Barker's mill. But spargers are sometimes driven from the shafting by a light belt or cord, with the object of ensuring regularity of motion, and con- sequently equal distribution of the liquor over all parts of the goods ; but if a self-acting sparger is well constructed, the irregularity of its motion must be extremely small. A point of far more importance than any slight irregularity of motion is the proper distribution of the holes in the arms of a sparger. In order that the liquor may be equally distributed over all parts of the goods, it is necessary that the quantities of water delivered from different points in the arms should be in exact proportion to the areas swept over by those points. If the first hole in the arm of a sparger is 6 in. from the centre, and the last hole distant 6 ft. from the same point, the latter hole will, as the sparger revolves, cover a circle twelve times as great as the former, and in order that the goods passed over by the two holes should be equally wetted, the delivery of water from the outer hole should be twelve times that from the inner. The required increase in the delivery from the outer ends of the arms may be obtained either by increasing the size of the holes, or by placing them nearer together as they are farther from the centre, or by combining these two methods. The sparger arms are sometimes straight and sometimes curved, the object of the curving being to cause the water to tend outwards in radial lines. The curvature to be given depends upon the speed at which the sparger revolves and the rate of flow. If the arms be formed of tubes of the same diameter throughout, the flow will be mo.-t rapid near the centre, th rate of flow at any point being approximately proportionate to the area of the discharging holes beyond that point. The best practice is to taper the arms gradually outwards, observing that the sectional area at any given point is at least equal to the combined area of the discharging holes beyond that point. If the taper of the arms be properly proportioned, the rate of flow will be constant at all points. Whether the arms are curved or straight will then make but little practical difference, so long as the sparger revolves at the usual moderate speed. The next apparatus in the order of use is the underback, which receives the wort from the mash tun. In some breweries, the wort is run direct into the coppers. The underback is a necessity where the coppers are situate at a higher level than the mash tuns. Underbacks are of various shapes and materials, chiefly wood, and rectangular. A circular form is better, as it is more easily kept clean. 396 BEVEEAGES. When cast iron is used it should be lagged with felt and wood, unless the wort can be very rapidly raised into the coppers, or unless the underback is fitted with steam pipes, so that the temperature of the wort may be maintained. The underback should be situate so that the taps through which the wort is discharged are in full view. In drawing off the wort, the taps are at first partially opened, being more fully opened when the wort runs off clear. The wort is generally drawn from four or more points in each mash tun, and in the event of any tap not delivering clear wort, it is shut off for a time. The appearance of the wort will vary according to the kind of malt used. The wort drawn from the first mash should closely resemble in colour the mixture of malt used, and it should have a close and tough, silvery white head, changing to a delicate cream colour. The temperature or tap-heat at which the wort is drawn varies according to the nature of the malt used ; but it is about 62 to 63 (144 to 146 F.). If the heat of the mash be too high, the head on the wort will have a brown tinge ; and if too low, the head will be deficient in closeness and firmness, and the wort will not be bright or well flavoured. Wort of this kind is particularly liable to acetification, arid it should be exposed to the air as little as possible. Wort of any kind is not benefited by exposure at this stage, and should never be allowed to remain in the underback longer than is necessary. When the wort has been drained into the underback, the mash tun is cleared of the waste malt or grains. This is ordinarily done by men with wooden shovels, but involves waste of labour in large and deep tuns. A better method is to provide the tuns with openings in the side near the bottom, communicating with shoots. The wort when drawn from the mash tun is composed of water, glucose or saccharum, and gum or mucilage, together with small proportions of starch, gluten, and albumen. During the early part of the process of boiling, diastase effects the conversion of the starch into sugar, dextrine, and gum ; and as the boiling goes on, the wort is concentrated, and a certain proportion of the albuminous matter present is deposited in a flocculent form. The hops are added to the worts at this stage. Boiling. The time during which the boiling must be continued will depend upon several cir- cumstances, such as the evaporative power of the copper and the amount to which the wort has to be concentrated. Generally the proportion evaporated during the boiling is about one-seventh ; and there is a further loss by evaporation as the wort cools down from the boiling point. In determining the duration of the boiling, the time required-^to obtain the necessary extract from the hops has to be considered. The stronger the hops, the longer boiling they require to obtain the full extract. The quantity of hops added to the wort depends upon the quality of the beer being brewed and the time it is intended to be kept. The measured quantity of hops is sometimes merely thrown into the copper, and stirred into the wort ; sometimes the hops are picked out and strewn on the surface, where they are allowed to remain for some time before being stirred in. The object of surface treatment is to allow the hops to be permeated by the rising steam, thus opening the pores before immersion in the wort. When boiling takes place in an open copper, the layer of hops on the surface of the worts prevents contact with the atmosphere. In many breweries, where two or three mashes are made, the hops, after boiling with the wort from the first mash, are discharged with it to the hop-back, and are returned into the copper to be boiled with the second wort, and so on. This is the general practice at the London breweries, and in some the hop-backs are fitted with elevators, by which the hops can be transferred to the coppers. At Charrington's, a long Archimedean screw, similar to those used for transporting malt or grist, placed at an angle of about 30, is used for raising the hops from one of the hop-backs to the copper. When hops are treated in this way, the moisture finally retained in them, which, unless the hops are allowed ample time for drainage, will amount to one barrel for every 60 Ib. of hops, is only of the strength of the wort with which they were last heated, and is of comparatively little value. Another plan is to discharge the hops from the copper with the first wort, and allow them to remain in the hop- back, the succeeding worts being merely poured over. This plan effects a gradual weakening of the liquor retained by the hops. Another method of preventing loss by the retention of wort, is to subject the wort to pressure. At Salt's brewery at Burton the practice is, with the best pale ales, to boil the hops with only the first wort. After discharge from the copper with the wort, they are removed from the hop-back and pressed, and are then available for another brewing. The hops are sometimes boiled with the first and second worts, and are then pressed, so as to thoroughly remove any wort held by them. At Allsopp's, Bass's, Salt's, and other large breweries, hop presses, worked by hydraulic power, are used, whilst in smaller establishments screw presses are employed. At Younger's brewery at Edinburgh, the wort is expelled from the hops in centrifugal drying machines. Extended series of experiments on heating by tubes containing steam have been made, and very rarious results have been obtained by the several authorities. It will be sufficient for general purposes to be enabled to calculate the amount of surface necessary to boil or to evaporate one barrel of water in one hour by means of steam pipes, and as well to furnish similar data for steam- BEER. 397 heated boilers with double bottoms. The steam may be assumed us at 30 Ib. pressure a square inch above atmospheric pressure. A barrel of water weighs 360 Ib., and to increase its temperature from 52 to 212 F.. or 160, it is necessary to impart 360 x 160 = 57,600 thermal units. As the latent heat of steam at atmospheric pressure is 966 "6, additional heat amounting to 360 X 966 '6 = 347 '976 thermal units is necessary to convert a barrel of water into steam ; or a total of 405,576 thermal units is required to evaporate one barrel of water from an initial temperature of 52 F. Proceeding in this way, it has been calculated that the areas of steam-heated surface required to raise one barrel of water an hour from an initial temperature of 52 F. to the boiling point, is for Copper steam-pipes Sq.ft. Iron Sq. ft. Copper with double bottom .. .. 2 Cast-iron boiler with double bottom .. 4 The areas of steam-heated surface required to evaporate one barrel of water an hour from au initial temperature of 100 (21^. F.) are: Sq.ft. Copper steam-pipes 24i Iron . 40 Sq.ft. Copper with double bottom .. .. 30 Cast-iron boiler with double bottom . . 73 The same data for 100 gallons are : To boll . To evaporate. Copper steam-pipes 4f sq. ft. . . 67 sq. ft. Iron ..8 .. Ill Copper with double bottom . . . . 5 . . 82 Cast-iron boiler with double bottom 12| .. 203 Graham is of opinion that unboiled wort, after fermentation, no matter how vigorous the yeast may have grown, never produces sound ales. Worts therefore must be boiled, and the action prolonged, so that the albuminous substances may be broken down in complexity, their activity destroyed, and at the same time colouring matters produced as in malting. In the boiling process, if there should have been, by chance, any insoluble starch carried over with the wort, it will be converted into soluble starch, but not into dextrine, for soluble starch is not converted into dextrine by the action of boiling. If any insoluble starch is run into the copper, that starch will be found throughout the subsequent stages. Dextrine in the boiling process is not converted into sugar* although some brewers hold that opinion. According to the present theory of brewing, boiling may be considered a necessity. Some theorists assert that it is not required, but no practical progress has been made in evidence of good results arising from omission of this part of the brewing process. By boiling, two results accrue, the elimination of a large quantity of albumen from the beer, which is completed after about twenty minutes from the commencement of boiling, and the absorption by the beer of the bitter principle of the hop. But for neither of these results is ebullition necessary, as both may be attained by exposure of the wort to certain high temperatures. With low-dried malts, heat below the boiling point of water will precipitate the albumen of the malt, and a temperature either higher or lower will abstract the better principle of the hop, with, however, slight differences of flavour, resulting from different temperatures. Boiling is practically necessary as a means of evaporation. A copper can easily be made to evaporate 15 per cent, of the water from the beer while the albumen and hop are under treatment, allowing of an equivalent of water being used in the mash tun to extract the malt. Coagulation of the albumen by boiling may be seen, when a sample of the wort is taken in a glass ; where the malt is low-dried and unsafe, the flakes are large, but when the malt is new and has been well dried the flakes are small. The precipitation is less from the second and third boilings of the mash tun, than from the first; but notwithstanding this fact, it is the practice to boil the lighter mashes longer, for what purpose there does not appear sufficient reason to show, except that the first portion of the mash cannot be boiled long unless it is a very light brew, while the after portion may be boiled for evaporation as long as the brewer may desire. Boiling is continued for about two hours for the general class of beer. For export beer, where a great quantity of hop has to be boiled down in a single copper, three hours are sometimes allowed. Heavy beer will require only one to one and a half hour, as the greater density of the wort is the cause of considerable increase of temperature in the copper. If heavy beers are boiled too long, the pale wort becomes brown, and a flavour similar to that of porter is given to the beer. Coagulation, and the discolouring of strong worts, occur in comparatively shallow depths, say about 4 ft. in some coppers, so that coppers should be made wider for strong beers than for light beers. The boiling of heavy beers should always be followed by the boiling of light beer, in order to work out the mash-tun products, and utilize the half-extracted bitter of the hop, as well as to recover the strong wort absorbed by the hop in the boiling of the heavy beers. The method of working with repeated boilings and returning the contents of the copper is highly economical, 398 BEVERAGES. and is generally pursued in the porter trade, where three boilings and returns of hop are common. Double boilings of hop are, however, supposed to be the safe limit in beer brewing, and many large brewers will not exceed one boiling with the hop, but disperse the quantity boiled over the malt, amongst the boilings of the mash extracts from which the worts have been taken. In this case, the hop is sent to be pressed to obtain the final amount of extract. It is the opinion of some brewers, who have had large practice, that reboiling of the hop affords great economy in brewing, and is perfectly safe when exposure to air is prevented. Most of those who have failed in trials of reboiling have worked with high final temperatures, technically termed high tail heats, which have given unsound products in the mash tun, and these, acting on the hop in the copper, extract from it an astringent principle imparting a bad flavour to the beer. For the production of a fine beer, more depends upon boiling than brewers generally admit. There is more that should be considered than mere ebullition or mere attainment of 100 ; the influence of barometric pressure, shape of the copper, whether it is closed or open, are of great importance, but have not received that attention which experiment lias shown them to merit. The peculiar flavour of London porter is undoubtedly due to the particular method of boiling, and to the use of large boiling coppers. A column of water 2 ft 3 in. high, gives a pressure of 1 Ib. a square inch, and a temperature difference at the two extremities of about 1, when heated as beers usually are, no that a boiler of 12 ft. in depth may have a difference of about 5 (8 F.) from the temperature of an ordinary beer copper. A wide copper, that allows freedom to the currents of ebullition, keeps its wort cooler than a narrow copper, in which the upper and downward currents come into contact. For this reason a wide bulging copper, with an ascending current in the centre and descending currents at the side, is best fitted for pale beer ; and a deep copper with almost perpendicular sides, by constricting the space for circulation and causing the descending currents to return upon the ascending currents, in other words, the cold currents upon the hot, is best for porter. In boiling, any hindrance to circulation causes increase of temperature. The wort at the bottom of the copper, loses solidity, becomes frothy and thus loses its conducting power, so that the copper bottom attains a temperature which renders the copper bad for ale, but better for converting extract of black malt into porter. Boilers with steam tubes at the bottom, and a false bottom at some distance above the tubes, intended to keep the hop from contact with the source of heat, are unsuccessful, because there is no circulation, and the wort beneath the false bottom is superheated, whilst that above remains cold. In Scotch breweries, the coppers are much wider than they are deep, whilst in the West and North of England they are deeper than wide; on this account Lancashire beer takes its peculiar flavour. The high temperature employed in boiling Lancashire beers is beneficial only so long as the malt is properly cured, and so liried as to approach an amber colour, but, without this preparation of the malt, it is useless to attempt rectification in the copper. It is agreed in the best practice that extra heat in the copper will not give additional keeping quality to either black or pale beers, unless the malt has been cured and heated to correspond with the temperatures of the coppers. Narrow coppers are wasteful and troublesome, because the contents are liable to be forced over the lips from the want of space for the currents of ebullition. Scotland and Lancashire may be regarded as presenting examples of the extreme limits of form for coppers. In London breweries, domed coppers are employed, and this may in some measure account for the superior flavour of London porter. Porter must be boiled at a temperature of 107 to 110 (225 to 230 F.), and this temperature can be attained in a straight-sided boiler, well fired, by boiling at a charge depth of 12 ft., or with a pressure in a small domed-boiler of 4 or 5 Ib. a square inch. Domed coppers, besides the safety valve have a vacuum valve to prevent collapse ; steam boiling is attended with some diffi- culty unless carried out in double-bottom coppers, which require the use of tubes to give 50 per cent, of steam surface over that of fire surface. Graham is of opinion that long boiling is m ce.ssary, and that a portion of the quantity of hops should be added after the first half-hour s boiling, the scum removed, hops again added, and boiling continued for an hour or an hour and a half, as may be required. All beers when kept for a few months, age and lose the distinctive flavour of the hop. In the hopping of beers, the range of quantity between 4 to 24 Ib. a quarter occurs in practice. Scotch mild ale is made with 4 to 6 Ib. to the quarter, and Scotch pale ale with 10 Ib. of hop ; Burton mild ale, 12 Ib. ; Scotch export ale, 16 to 20 Ib. ; Burton home pale ale, 20 to 24 Ib. Porter, for early sale, is made with 8 to 10 Ib. of hop, and for export, with 12 to 14 Ib. good quality. Stout for home use is hopped with 12 to 14 Ib. ; and export stout 16 to 18 Ib. a quarter. The hop for porter and stout is always rebelled. In raw hopping the beer in cask, 1 Ib. to the barrel is usually allowed for home sales, and 2 Ib. to the hogshead for export beers. The finest new hop is selected for this purpose ; delicate for home, and strong for extract beer. Vatted ales are always raw hopped. Stouts are sometimes thus treated, according to the practice of the brewer. In the best practice, it is generally admitted to be a mistake to hop the beer both in copper and cask, especially for the purpose of correcting stale malt ; a better plan is to re-dry the malt BEER. 399 Cooling. Before the introduction of refrigerating apparatus, beer wort was cooled on cooling floors, flats of buildings floored and flanged round to a depth of about 6 in. These floors were of oak, teak, cast iron, or copper, but the loss of beer from the old wooden coolers through absorption by the wood was sometimes equal to 5 per cent, of the net results of the brewing. Considerable difference of opinion occurs as to the advantages of refrigerators over coolers, but beyond the advan- tage of evaporation, in helping to remove the mash water, there is no benefit from the use of a cooler. The most economical and safest brewing is that conducted with refrigerators, so that the wort may be run direct from the hop-back through the refrigerator to the permeating tun. If the refrigeration is effected with cold water, the supply necessary is equal to double that needed to cool with the cooler, if the wort is at a temperature when it begins to run, of about 55 (130 F.). After boiling, the worts are, as a rule, discharged from the copper or boiling back, as the case may be, into the hop-back, a large tank or vessel fitted with strainers for separating the hop from the wort. In those breweries in which the wort has to be pumped from the hop-back into the coolers, the former, in addition to acting as a strainer, serves as a reservoir from which the pumps can draw. Sometimes the hops are placed in the boiling back, enclosed in a perforated sheet-iron vessel, and as in this case they cannot mix with the wort, the latter does not require to be strained after boiling, and it is therefore run direct from the boiling back to the coolers, no hop-back being used. A hop-back should always be capable of containing the full contents of the copper in connection with which it is worked, and if it is of any great size, it should be fitted with elevating machinery, for returning the hops to the copper. To enable hop-backs to act as strainers, they are fitted with perforated false bottoms, constructed generally of cast-iron plates, arranged to be readily removed for cleaning purposes. The space below the false bottom communicates either with the suction pipe of the pumps, or with a pipe leading direct to the coolers. The perforations in the false bottoms are sometimes narrow slits about / T in. in width, and 2 in. or 3 in. long, and sometimes small holes about | in. or -^ in. in diameter. In either case, the perforations are well countersunk on the inner side of the plates, so that the thickness, through which the narrow openings extend, is not great. The draining power of any hop-back varies directly as the area of the openings in the false bottom, and, as these openings must not be limited in size, they should be placed as closely together as possible. As the flow of the wort through the perforations is accelerated by increasing the depth of wort, there has been an erroneous tendency to make hop-backs deeper than needful, to obtain increased head. With a given quantity of wort, an increased depth can only be obtained by a reduction of the horizontal, and consequently of the drainage, area, hop-backs, as a rule, being furnished with perforations only at the bottom. The reduction of drainage area consequent upon the increase in depth varies directly as that increase, whilst the velocity of flow through the perforations in the false bottom is augmented only as the square root of the increase in depth. For example, a hop-back has a drainage area of 40 sq. ft., and the wort stands at a depth of 4 ft. above the false bottom. The theoretical velocity of flow through the perforations should be about 16 ft. a second. If the hop-back be supposed to be contracted until the horizontal area is reduced to 10 sq. ft., the depth of the wort will be increased to 16 ft., and the flow due to this head will be 32 ft. a second. The velocity of flow will only have been doubled, whilst the drainage area has been reduced to one- fourth ; and the quantity of wort drained from the back in a given time will only be half that in the former case. The greater the depth, the greater also will be the quantity of hops deposited on each unit of area of the bottom, and the more resistance offered to the passage of the wort. When the depth of the wort above the false bottom is 5 ft. 9 in., there will be about one barrel above each square foot of bottom area, and the quantity of hops deposited a square foot will nearly corre- spond to that quantity a barrel, whilst, if the depth is but 2 ft. 10 in., there will be but half this quantity deposited a square foot, and so on. A certain portion of the drainage area can be kept clear by raking away the hops ; but the area covered by the hops will always depend upon the depth of wort originally contained in the back. Hop-backs should, therefore, not be more than 2 ft. 6 in. or 3 ft. deep above the false bottom. Where the wort is pumped from below the false bottom of a hop. back, an artificial head is caused by the exhaustion, if the pumps are sufficiently powerful. In a hop-back at Charrington's brewery another plan has been adopted, to avoid loss of drainage area by the deposit of hops. This hop-hack is provided with vertical grilles, in addition to the ordi- nary perforated bottom. The back, 48 ft. long by 1 2 ft. wide and 5 ft. 3 in. deep, is provided, at a distance of 6 ft. from each end, with a diaphragm or partition. The partitions are each formed of a series of angle irons placed vertically side by side, with spaces \ in. wide between. These vertical angle irons, forming the grids, are riveted at the top to an angle iron. Between the diaphragms or screens, the hop-back is provided with a false bottom, placed 3 in. above the real bottom, and constructed of cast-iron plates. The cast-iron plates are each 3 ft. long by 1 ft. wide by T 9 ff in. thick round the edges, and | in. thick at the perforated portion. The holes are T ^- in. in diameter, and are deeply countersunk on the under side, and are placed at 1 in. pitch. The space between the false bottom communicates at each end with those portions of the hop-back beyond the 400 BEVEEAGES. vertical grilles, the end openings being each protected by a curved grill, formed of angle irons similar to those used in the vertical screens, but placed closer together. The bottom of the back is laid with a fall of -J- in. a foot from each end towards the centre, where a gutter, 3 ft. wide by 5^ iu. deep, is furmed, with which tlie suction pipe of the pumps communicates. The action of this arrangement is as follows : When the worts are poured in, drainage takes pi .ce through the false bottom between the diaphragms in the usual manner; and in addition to this the wort also passes through the vertical grilles or diaphiagms into the end divisions of the back. From these latter it passes through the curved grilles, which serve to separate any hops that may have passed througli the vertical diaphragms, and so into the space below the false bottom, and thence to the pumps. When drawn from the hop-back, the wort has to be cooled to the temperature at which it is placed in the fermenting tun. This temperature varies from 12 to 18 (54 to 64 F.), aud allowing for some loss of he.it in th hop-back aud communicating pipes, tne temperature of the wort has to be reduced about 83 (150 F). This reduction is sometimes effected by exposing the wort to the air hi shallow vessels, or coolers ; sometimes by passing it througti a refrigerator, and very generally by a combination of the two methods. Wooden coolers are those most frequently met with, probably on account of cheapness, but they are open to many objections. They are usually made of Dantzic deals about 1J in. thick, the boards being pegged to the joint pieces with wooden pins. The coolers should be laid with a slight inclination towards the point at which the wort is drawn off, and the boards should be planed as smooth as possible, so that they may be more readily kept clean. Too much care cannot be paid to the cleanliness of the coolers, and they should be frequently well washed with lime water. If the coolers are not in almost continual use, it is advisable to keep them covered with water when nut required for the wort, as the pores of the wood, which have been opened by the action of the hot wort, are prevented from absorbing air which would come into contact with the next wort, and cause incipient fermentation, generally termed foxing. Metal coolers are generally placed so that their under sides are exposed to the air as well as the upper surface, and the cooling effect is thus increased. This arrangement should be adopted in all metal coolers. At Truman's, the coolers are of copper, and are two in number, each 110 ft. long by 25 ft. wide. They are made of thin copper, the weight a square foot being about 3i lb., and are supported merely on joists, the under sides being freely exposed to the air. The wort is not allowed to remain in these coolers, but is run over them in a thin stream to a refrigerator, which completes the cooling process. These coolers are capable, under ordinary circumstances, of cooling about fifty barrels of wort an hour from the boiling point to a temperature of 43 (110 F.) ; the combined surface of the coolers being ooOO sq. ft. This is a very high result, and is partly due to the wort being kept in circulation over the coolers, and to the coolers being made of thin copper. Special rules for the dimensions of coolers are inadmissible. Besides the variations in tempera- ture and state of the atmosphere, which exercise a most important influence on the efficiency of cooling surface, the position in which the coolers are placed, and the degree in which they are protected from free currents of air by surrounding buildings, modify considerably their refrige- rating power. Coolers should always be placed so that the air has free access, and to thia end it is usual to make the walls of the rooms containing them of louvres, which can be opened as may be required. If the wort is to stand on the coolers, these should be of such size that the depth of the wort may not exceed 2 in. or 2 in., or, in other words, have an area of about 36 sq. ft. a barrel, each square foot thus carrying a gnllon of wort. When covered with wort to this depth, a well-situated cooler will, under ordinary circumstances, effect the required reduction of temperature in six to eight hours. The cooling power of a certain area of cooler surface may be increased by causing the wort to flow over the coolers instead of remaining quiescent, or by causing the surface to be swept by an artificial current of air. If coolers are worked in connection with a refrigerator, so that there may be a regular flow of wort, they should be of considerable length in proportion to the width, or if of nearly square shape, divided by partitions placed so as to leave passages past the alternate ends, BO that the wort may have to travel through a series of long and comparatively narrow channels. The wort should bo drawn off from different points in the width of the stream, either through a number of openings communicating with a single pipe, or by letting the wort fall over a kind of weir extending across the stream. By these means, greater uniformity of current will be ensured. Of the extent to which the cooling power of a given area of wort surface is increased by the passage over it of a current of air, some idea may be gained from Dnlton's experiments on evapora- tion at natural temperatures. With water at 100, and an atmospheric temperature of 15, it was found that a surface of about 27 sq. in., which would evaporate 2'1 grains a minute in still dry air, would evaporate 3 '3 grains a minute when there was a brisk current of air passing. When coolers are placed at an elevated part of the brewery, as re very usually the case, they are generally BEER. 401 subjected to natural currents of air of greater or less force; but in addition to this it is the praotice in iuany breweries to assist the cooling by the use of fans. Fans, having each three or four vanes, are caused to rotate horizontally immediately above the surface of the wort, the blades or vanes being placed with their surfaces inclined to the plane of rotation so that the current of air is deflected downwards as well as caused to spread radially. Fans arranged in this way not only cause a constant change of the air in contact with the wort, but give rise to currents in the wort itself, and thus tend to equalize its temperature throughout. Another arrangement for obtaining an artificial current of air over the wort has been adopted. A cooler is attached to each pair of mash tuns, and is of sheet iron, supported on open joists, so that the under sides are freely exposed to the air. At one corner of the cooler is a fan, communi- cating with a wooden trunk, led along one side of the cooler, having openings through which the air can enter. The moist air, drawn otf by the fan from the surface of the wort, is expelled through a pipe, which rises through the roof of the building. The best brewing practice is now tending to the employment of refrigerators alone for cooling the wort, and for this there are many reasons. A lengthened exposure to the atmosphere, to which the wort is subjected on the coolers, is far from beneficial, and in comparatively warm weather apt to induce acidity. There is also a loss by absorption on the coolers, and a loss by evaporation. As this latter loss is merely of water, it may, at first sight, appear to be of but small consequence ; in reality this is not the case. Under ordinary circumstances, the loss by evaporation alone is about 8 per cent., and this involves the use of 8 per cent, more liquor in washing than would otherwise be necessary to produce a wort of a given final strength. The quantity of wort to be boiled is also increased 8 per cent., and since the quantity of fuel used is, in large brewings, proportional to the quantity of wort and liquor heated, an additional consumption of 8 per cent, of fuel is the result. When the wort is cooled entirely by passing it through a refrigerator, the loss by evaporation is of course nil, and since a less quantity of liquor will have to be used in mashing, there will be a less quantity to heat as liquor, and to boil afterwards as wort. In many cases, the hot water obtained from the refrigerators may be fed into the liquor boilers. Again, where fans are used, the expense of the engine power required to drive them has also to be considered. Against the disadvantages of the coolers are to be set the expense of the refrigerator and the cost of supplying it with water, either by pumping or otherwise; in all but very exceptional cases, the balance will be in favour of the use of the refrigerator. In many instances, the water heated by passing through the refrigerator can be used for brewing purposes, and even when the water used for refrigeration is not available for brewing, the supply of hot liquor can generally be turned to some account. Coolers are best employed only for effecting the reduction of the temperature of the wort from boiling point to 43 (110 F.) or 50 (120 F.), the cooling being completed by a refrigerator. In the cooling process, a precipitate is formed due to two causes, the simple action of cold being one. Part of the albuminous matter, that which combines with tannic acid to form tannate of albumen, is precipitated, the precipitate being also due to oxidation. During a long cooling from a high temperature, as when the worts are cooled upon open coolers, oxidation is set up by the air, the most dangerous temperatures being from 39 to 50 (100 to 120 F.). If starch is present in soluble condition it is likely to set up decay, which Graham states is not due to the action of vital organisms, but to the division of the grape sugar or glucose into two equal molecules, each containing C 3 H 6 O 3 , or lactic acid ; the molecule of glucose simply breaks up into two mole- cules of lactic acid, no gas being given off nor precipitate formed, but the acid is produced by simple alteration of the molecular arrangement. This action is likely to occur in a prolonged exposure to temperatures between 16 and 38 (60 and 100 F.). Rapid cooling therefore is essential. Wort cooled on cooling floors is stated to be sound and good if it presents a black appearance on the surface, a reddish hue being indicative of putrefaction. When this red colour occurs, the coolers must be thoroughly cleansed with chloride of lime and quick lime, not with bisulphite of lime. Graham considers that cooling should be continued to about 18 (64 F.) or 19 (66 F.). In Burton, it is carried to 14 (57 F.), and in Bavaria, where the bottom fermentation process is employed, to 6 (42 F.). Fermentation. When cooled, the wort is led to the vessels or tuns in which it is to undergo fermentation. The nature of the chemical changes known as fermentation, and the conditions under which they take place, have been described and indicated in a former article (see Alcohol, p. 194). The sugar in the wort on its transformation into glucose takes up two equivalents of water ; therefore the combined weights of the carbonic acid and the alcohol resulting from the fermenta- tion is greater than that of the sugar originally contained in the wort. It follows that there should be an increase in the specific gravity of the solution or wort during the time thnt the conversion of the cane sugar into grape sugar is taking place. This is actually the case, and it is a fact of which the brewer takes advantage. As the evolution of carbonic acid gas progresses, the specific gravity of the liquid is observed to decrease ; and this gradual reduction of specific gravity is by brewers termed the " attenuation." The attenuation of the wort is accompanied by a rise in tem- 2 D 402 BEVERAGES. pcrature, and it is by this increase of temperature, combined with the reduction of the specific gravity, as observed by the saccharumeter, as, well as by the appearance of the head formed, that the brewer is enabled to judge how the process of fermentation is proceeding. In the fermentation of a malt wort, the conversion of the saccharine constituents into alcohol and carbonic acid does not occur alone. The albumen and gluten become insoluble in the alcohol formed by the process of fermentation. Under the circumstances of the English method of pro- cedure, one portion of these insoluble substances is buoyed up by the ascending globules of carbonic acid forming the frothy head which collects on the surface. The remaining portion of the insoluble matters is deposited as bottom barm, which consists of gluten mixed with the denser impurities of the wort, and is a cruder material than the yeast floating on the surface. The proportion that the floating yeast will bear to the bottom barm will vary with the nature of the malt, the heat of the mashing process, and with the temperature at which the fermentation is carried on. In the case of the Bavarian brewing process, in which the fermentation is allowed to proceed very slowly, a mere film is formed on the surface of the wort, the insoluble matters being almost entirely deposited as a viscid sediment, termed the " unterhefe.'' The initial temperature at which the wort is pitched or mixed with the yeast in the fermenting tuns exercises an important influence upon the energy of the fermentation, and it has to be regu- lated according to the atmospheric temperature of the tun room and the strength of the wort. According to the English practice, the pitching temperature ranges from 11 (51 F.) to as high as 18 (64 F.), but in the Bavarian system it is kept as low as 7 to 10 (45 to 50 F.) In winter, the air, being at a low temperature, tends to check the energy of the fermentation ; whilst, in summer, as the air is frequently at a higher temperature than that at which the wort is pitched, the fermentation is more difficult to control. For these reasons, it is necessary that the pitching temperature should be lower in summer than in winter, unless means are provided for keeping the tun room cool. The smaller the vessels in which the fermentation is carried on, the greater will be the surface exposed by them in proportion to their contents, and the greater therefore will be the influence exerted by the atmospheric temperature. So long as the temperature of the air in the tun room is below that of the wort, the energy of the fermentation may be checked by dividing out the wort into a number of small vessels ; but if the atmospheric temperature in the tun room is higher than that of the wort, the reverse effect would, of course, be produced by such a system of division. Care is generally taken to so construct and place the tun room that it may be kept at a moderate temperature even during the hottest weather, whilst in some instances special arrange- ments for cooling the air are adopted. Another point to be considered with respect to the initial temperature is the character of the beer to be produced ; a light beer, intended for immediate consumption, may be pitched at a comparatively high temperature, but in the case of a strong stock ale the initial temperature should not be higher than 12 or 13 (54 or 56 F.), and it should not be allowed to rise more than 10 (16 F.) during the process of fermentation. Pale ales, also, which usually receive a liberal allowance of yeast, should be pitched at a low temperature. The quantity of yeast to be added, like the pitching temperature, depends upon so many circumstances that it is impossible to give any general rule. The best yeast is considered to be that obtained from pale gyles towards the completion of alcoholic fermentation, this yeast being denser than that thrown off during the earlier stages, and free from admixture with old yeast that has been added to the wort to induce fermentation. Yeast, if collected from the stillions and placed in reservoirs or tubs, is apt to work and lose strength ; it is better to let it remain in the stillions with a portion of the drawings, until required, when the draw- ings should be strained off. If the yeast has to be stored, it is best covered with water, and kept in the coolest place available. The water should be quite cool, and should be occasionally renewed. The heavier, or in other words the stronger, the wort, the greater will be the proportion of yeast necessary, and this proportion will also be affected by the degree of attenuation to be produced. The quantity of yeast required depends also upon the temperature at which the gyle is pitched ; the higher this temperature, the less the quantity of yeast necessary. Black states that if the worts are got together in the gyle tun at a temperature under 15 (60 F.), about 1 Ib. of yeast a barrel for every 10 Ib. of gravity, as indicated by Long's instrument, will be found to produce a loss of 1 Ib. in attenuation for every degree of heat gained, and he considers this to be a good working rule. It should be remembered in all cases that a deficiency of yeast is better than an excess, since it is possible, if the fermentation is sluggish, to add more yea&t ; whereas, if the latter be in excess, a too violent fermentation may be set up, which it may be impossible to control. Yeast added after the fermentation should be first mixed with a portion of the wort, and then well stirred in ; but this practice is not to be recommended, since it is likely to impart a rank flavour of yeast to the beer.< In all cases where the weight of the yeast per gallon is not accurately known, the yeast should be apportioned out by weight, and not by measurement. Before the yeast is placed in the tun, it is mixed with a small quantity of wort, and left in a warm pLice until fermentation commences, when the mixture, termed "lobb," may be added to the gyle in the tun. Some brewers add the full BEER. 403 quantity of yeast at once, whilst othera reserve a certain proportion to be added subsequently to stimulate the fermentation. So long, however, as the quantity of yeast required ia accurately known, the former system appears to be preferable. In a thoroughly healthy fermentation, the rise of temperature which ensues as the process goes on should be steadily accompanied by a decrease in the gravity of the wort, or, for every degree of heat gained, a pound of saccharine matter per barrel should be transformed into carbonic acid and alcohol, an eifect which will be shown by the saccharometer. Of course, this correspondence between the increase of heat and the attenuation attained is to some extent liable to modification by extremes of heat or cold. The stages of a healthy fermentation are as follows : Some six or eight hours after the yeast has been added, minute bubbles of carbonic acid gas begin to rise, and a thin creamy froth is formed, first round the edges of the tun, but gradually extending over the whole surface of the liquid. As the temperature rises, and the decomposition of the saccharine matter becomes rapid, the evolution of the carbonic acid gas takes place more freely, and, as a consequence, the froth rises, forming what is termed the " cauliflower head." At this stage, the aroma becomes very perceptible. The cauliflower head should rise two or three feet above the surface of the gyle, and it should be of a brownish-white colour ; a bluish-white colour at some parts indicates un- soundness. The next change consists in the breaking up of the cauliflower head into what ia termed the " rocky head." The rocky head is produced by the bursting of the globules of froth, the yeast at first thrown off not being sufliciently viscid to retain the accumulation of carbonic acid. At this stage, the head should fall some three or four inches, and the aroma should be very pungent and vinous. In the next and last stage, the head again rises, forming what is known as the "close yeasty head," this having the appearance of yeast all over the surface. If the fermentation be a healthy one, the head will at this stage be covered with small bubbles at the top, these constantly bursting, discharging their gas, and being replaced by new ones. This goes on until the beer is considered to be ready for cleansing or skimming, a process which consists in removing the yeast from the surface. Different methods of conducting the cleansing will be described later. The object of the operation is to prevent the imparting of a bitterness or yeast-bitter flavour to the beer, which might be the case if the beer were allowed to remain in contact, at a temperature approaching 21 (70 F.), with yeast that had to some extent entered into putrefactive fermentation. During the progress of fermentation, the temperature of the liquid rises, the maximum heat being attained when the fermentation is at its highest point. In some instances, the rise of temperature is upwards of 14 (30 F.), but generally lower, and in the case of stock, and Scotch ales, it is as low as 10 (16 F.). If the heat is allowed to rise too high, the glutinous constituents of the beer are not perfectly removed in the yeast, and as the gyle does not cleanse perfectly, an after fermentation ensues, technically termed the "fret." On the other hand, too low a temperature causes sluggish fermentation, and, as a consequence, the beer is apt to gain a yeast-bitter flavour from being retained too long in contact with the yeast. To avoid these results, various contrivances are employed to keep the temperature at all times under control. In connection with the subject of fermentation, it is advisable to discuss briefly the determination of what are called " original gravities," or the gravities of the worts from which any given samples of beer may have been made. According to Act of Parliament, 10th Victoria, cap. 5, a drawback of 5s. a barrel is granted on all beer exported, on condition that the worts before fermentation were not of less specific gravity than 1'081. A brewer knows the strength of the wort from which the beer has been made; but it is necessary that the revenue officer also should have the means of obtaining independently from a sample of the beer the same information, and this necessity has led to the close investigation of changes which take place during fermentation. For each sample of beer there have to be determined the original gravity of the wort from which it was produced, the specific gravity of the beer itself, or, as it is sometimes called, the beer gravity ; the spirit indication ; and the proportions of unfermented solid matter, or extractive matter, held in solution by the beer. The specific gravity of the beer can be determined by the hydrometer, while the extract gravity, or the specific gravity, of the beer without its spirit, may be obtained by par- tially evaporating a given quantity of beer, to expel the alcohol, and making up the original bulk by the addition of water. By comparison of the specific gravity of the beer with the extract gravity, an indication may be obtained of the quantity of alcohol in the beer. This quantity may also be ascertained by distillation, by the refracting power of the beer on rays of light, or by observation of its boiling point, which lowers with increase of alcohol. It is possible, if the amount of alcohol in the beer is known, to roughly determine the original gravity of the wort by increasing the extract gravity by the amount due to the quantity of starch sugar which would have to be decom- posed during fermentation to produce the known quantity of alcohol. Original gravities thus deter- mined, however, are useless for practical purposes, because the final or beer gravity is the result, not merely of the attenuation produced by the decomposition of the saccharine matter, but also of the changes effected in other constituents of the wort during the process of fermentation. In comparing the specific gravities of various solutions of sugar, malt, and other ingredients, 2 2 404 BEVERAGES. Graham, Hofmann, and Red wood take as their standard of comparison the proportion of carbon that a given solution contains, and they have proved that the specific gravity of a solution, containing a given proportion of carbon will vary to some extent according to whether that carbon is present in the form of sugar, dextrine, or extractive matter. The annexed table shows the specific gravities of various solutions compared in this way : SPECIFIC GRAVITIES OF VARIOUS SOLUTIONS CONTAINING EQUAL QUANTITIES OF CARBON. Carbon in Equivalent luoo parts by Weight of Solution. parts of Cane Sugar in 1000 parts by Weight of Solution of Cane Sugar. Solution of Starch Sugar. Solution of Pale Malt. Solution of Brown Malt. Solution of Caramel. Solution of Dextrine. Solution of Extractive Substance. Solution. 10-53 25 1010-1 1010-4 1010-0 1010-0 1008-7 1009-7 1008-9 21-05 70 1020-2 1020-8 1020-3 10-20-2 1017-3 1019-3 1017-8 31-58 75 1030-2 1031-3 1030-6 1030-6 1026-2 1028-8 1026-5 41-10 100 1040-6 1042-6 1041-2 1041-2 1034-9 1038-3 1035-5 52-63 125 1051-0 1053-5 1052-1 1052-0 1043-8 1047-9 1044-7 63-16 150 1061-8 1064-9 1063-0 1062-9 1052-8 1057-3 1053-9 73-68 175 1072-7 1076-0 1074-2 1074-0 1062-3 1066-9 1063-0 84-21 200 1083-8 1087-8 1085-5 1085-5 1071-8 1076-6 1072-7 94-73 225 1095-2 1099-4 1097-2 1097-2 1081-3 1086-3 1082-3 105-26 250 1106-1 1111-4 1109-0 1109-0 1091-0 1095-8 It has been stated that, when fermentation occurs in a solution of cane sugar, there is at first a slight increase of density, due to the transformation of the cane sugar into starch sugar, followed by attenuation, due to the formation of alcohol and the evolution of carbonic acid. In a wort con- taining cane sugar, a transformation of this into grape or starch sugar precedes the vinous fermenta- tion, and this change occasions an increase of gravity of nearly 3, in a solution of which the original gravity is 1055. The rate at which the rise in gravity occurs varies according to the amount of yeast added to produce fermentalion. A similar effect results when the transformation of the cane into starch sugar is effected by the addition of acids instead of yeast. The comparative densities of solutions of cane and starch sugar are given in the preceding table, and the fact that they differ is important, for the original gravity of a fermented liquor or beer must be different, according as it was derived from a wort of cane sugar or of starch sugar. Since, in a small wort, the saccharine matter is present in the form of starch sugar, there is no increase of density previous to fermentation. With regard to the densities of solutions of pale and brown malt, it is interesting to observe that the gravities of the solutions of the two malts agree very closely, and that they occupy a position intermediate between that of the two sugars. That the malt wort is of less density than a solution of starch sugar, containing the same proportion of carbon, indicates that a portion of the carbon in the wort exists in some other form than that of starch sugar ; for if the whole carbon of the malt wort were present in the form of starch sugar, the gravity of the wort should somewhat exceed that of the pure starch sugar solution, since a small proportion of alkaline and earthy salts exists in the malt infusion, and must add to its gravity. The carbon present in the small quantity of albumen of the malt could not affect the result materially. The lesser density of malt wort as compared with a solution of starch sugar containing an equal proportion of carbon is no doubt in part due to the presence in the former of certain proportions of dextrine and caramel, substances which both pro- duce solutions considerably lighter than those of starch sugar containing similar amounts of carbon. Both dextrine and caramel are forms of the sugar principle, and the presence of the former in a wort is due to the incomplete saccharization of the starch of the malt during the mashing process. The presence of caramel, or burnt sugar, is no doubt due to the changing of the starch sugar by heat during the process of kiln-drying the malt. It exists in larger quantities in highly dried malt than in the paler kinds, whilst in the case of the black malt used in porter and stout brewing, almost the whole of the soluble portion appears to be caramel. Graham, Hofmann, and Redwood also point out that a substance greatly resembling caramel is produced during fermentation, owing to the saccharine matter of the wort never being wholly converted into carbonic acid and alcohol, even under the most favourable circumstances. A portion of solid matter always remains which is unfermentable, even if the alcohol is distilled off and fresh yeast used. This residuary has been termed gummy substance, but when obtained by the fermenta- tion of pure sugar it partakes more of the character of caramel, or of glucic acid, particularly in the low gravity of its solution in water. Of pure sugar fermented, 4 4, 3 72, and 3 70 per cent, was con- verted into this substance in three fermentations, in which one and a half, three, and six measures of yeast were employed to one hundred measures of solution, containing one-seventh of its weight of sugar. This extractive substance may be obtained in the form of a dark-brown syrup by evapo- BEER. 405 rating the liquid after the completion of the fermentation. This syrup reddens litmus paper ; gives, like caramel, a transparent blue solution, with sulphate of copper and caustic potash in excess ; is not fermentable by yeast even after being boiled with sulphuric acid, whilst it is precipitated by baryta water, and when treated with subacetate of lead gives a brown precipitate more voluminous and of a lighter colour than the precipitate produced by the same means from a solution of pure caramel. That it is a compound of two or more substances is proved by the fact that a portion of it is precipi- tated by the addition of a solution of neutral acetate of lead. Solutions of this extractive substance have densities very closely agreeing with those of caramel containing similar quantities of carbon. The presence of this extractive substance, which is produced during the fermentation of malt worts, as well as sugar worts, appears to exercise a greater influence than dextrine in giving to fermented worts an apparent attenuation without a corresponding production of alcohol, and the more nearly the worts are exhausted by fermentation, the greater is its effect. The indication by gravity of the extractive substance is so much lower than that of starch sugar, that the former substance only indi- cates about five-sixths of the saccharine principle that has given rise to it. Hence it is that original gravities cannot be calculated on the assumption that the solid matter in beer is sugar, or a sub- stance having the same gravity as sugar. In the maturing of beer by time, an increase of attenua- tion is observed, which is no doubt due to the slow continuation of the vinous fermentation, with the disappearance of sugar and formation of alcohol ; but there is some reason to believe that the attenuation is not entirely due to that cause. Part of the loss of gravity appears to be occasioned by the change in condition of the saccharine principle, from that of starch sugar to that of the extractive substance, a change which involves a loss of specific gravity without a corresponding production of alcohol. During the process of fermentation of a malt wort, a change is produced in the proportion of albuminous matter ; this proportion is diminished in consequence of the formation of yeast, which causes a proportion of the albumen to assume an insoluble form. In a wort made from pale malt with hops, of the gravity of 1088, and containing 21 per cent, of solid matter, it was found that the nitrogen amounted to 0-217 per cent., and might be considered as representing 3 '43 per cent, of albumen ; whilst after this wort had been fully fermented the proportion of nitrogen was reduced to 0'134 per cent., corresponding to 2-11 per cent, of albumen. Solutions containing 2'11 and 3 '43 per cent, respectively of egg-albumen, have been ascertained to have the sp. gr. 1003*1 and 1004 '2, therefore the loss of albumen which took place during the fermentation of the wort corresponded to a reduction of gravity from that cause alone of l'l. In the same wort, the mineral constituents, consisting of soluble salts of the earths and alkalies, amounted to 443 per cent, before and 463 per cent, after fermentation, a variation of no practical importance. The determination of what is termed the " spirit indication " does not present great difficulty Graham, Hofmann, and Redwood have ascertained that a knowledge of the extract gravity and spirit indication of beer is sufficient to enable the original gravity to be determined with certainty. The following tables were compiled to enable the original gravity of a beer to be determined from an observation of its spirit indication. These tables show the number of degrees of gravity lost by an ordinary malt wort corresponding to the different degrees of spirit indication, the first table being intended for use when this indication is obtained by the distillation process, and the second when it is obtained by the more practical process of evaporation. When the distillation process is used, a convenient quantity of beer is carefully measured in a glass flask, and then placed in a retort fitted with a tubular condenser. ORIGINAL GRAVITIES BY THE DISTILLATION PROCESS.. Degrees of Spirit o i 2 3 4 5 6 7 8 9 Indication. 3 6 9 1-2 1-5 1-8 2-1 2-4 2-7 1 3 : 3-3 3-7 4-1 4-4 4-8 5-1 5-5 5-9 6-2 2. 6-6 7-0 7-4 7-8 8-6 8-5 9-0 9'4 9-8 10-2 3 10-7 11-1 11-5 12-0 12-4 12-9 13-3 13-8 14-2 14-7 4 15-1 15'5 16-0 16-4 16-8 17-3 17-7 18-2 18-6 19-1 5 19-5 19-9 20-4 20-9 21-3 21-8 22-2 22-7 23-1 23-6 6 24-1 24-6 25-0 25-5 26-0 26-4 26-9 27-4 27-8 28-3 7 28-8 29-2 29-7 30-2 30-4 31-2 31-7 32-2 32-7 33-2 8 33-7 34-3 34-8 35-4 35-9 36-5 37-0 37-5 38-0 38-6 9 39-1 39-7 40-2 40-7 41-2 41-7 42-2 42-7 43-2 43-7 10 44-2 44-7 45-1 45-6 46-0 46-5 47-0 47-5 48-0 48-5 11 49-0 49-6 50-1 50-6 51 2 51-7 52-2 52-7 53-3 53-8 12 54-3 54-1 55-4 55-9 56-4 56-9 57-4 57-9 58-4 58-9 13 59-4 60-0 60-5 61-1 61-6 62-2 62-7 63-3 63-8 64-3 14 64-8 65-4 65-9 66-5 67-1 67'6 68-2 68-7 69-3 69-9 15 70-5 406 BEVERAGES. Distillation is carried on until the whole of the alcohol is brought over, the alcohol being received in the flask in which the beer was originally measured. The alcohol collected is next made up to the original bulk of the beer by the addition of water, and the sp. gr. of the liquid is then carefully observed at a temperature of 60 by the aid of the weighing bottle or a delicate hydrometer. ORIGINAL GBAVITIES BY THE EVAPORATION PROCESS. Tegreesof ImSm. *0 '1 3 7 1-0 1-4 1-7 2-1 2-4 2-8 3-1 1 3-5 3-8 4-2 4-6 5-0 5-4 5-8 6-2 6-6 7'0 2 7-4 7-8 8-2 8-7 9-1 9-5 9-9 10-3 10-7 11-1 3 11-5 11-9 12-4 12-8 13-2 13-6 14-0 14-4 14-8 15-3 4 15-8 16-2 16-6 17-0 17-4 17-9 18-4 18-8 19-5 19-8 5 20-3 20-7 21-2 21-6 22-1 22-5 23-0 23-4 23-9 24-3 6 24-8 25-2 25-6 26'1 26-6 27-0 27-5 28-0 28-5 29-0 7 29-5 30-0 30-4 30-9 31-3 31-8 32-3 32-8 33-3 33-8 ! 34-3 34-9 35-5 36-0 36-6 37-1 37-7 38-3 38-8 39-4 9 4G-0 40-5 41-0 41-5 42-0 42-5 43-0 43-5 44-0 44-4 10 44-9 45-4 46-0 46-5 47-1 47-6 48-2 48-7 49-3 49-8 11 50-3 50-9 51-4 51-9 52-5 53-0 53-5 54-0 54-5 55-0 12 55-6 56-2 56-7 57-3 57-8 58-3 58-9 59-4 59-9 60-5 13 61-0 61-6 61-2 62-7 63-2 63-8 64-3 64-9 65-4 66-1 14 66-5 67-0 67-6 68-1 68-7 69-2 69-8 70-4 70-9 71-4 15 72-0 The number of degrees by which this specific gravity is less than that of water is the spirit indication. The spirit indication may be more readily obtained by simply subtracting the beer gravity from the extract gravity, a method used by the German brewers. This is a more convenient method than the former, since, to obtain the extract gravity, the beer has merely to be evaporated in an open flask, without collecting the spirit. In cases where the spirit indication has been determined by the latter method, the second of the foregoing tables has to be used to ascertain the original gravity. Thus, if the spirit indication is 9'6, and the extract gravity 1044'7, the original gravity will have been 1044'7 + 43 = 1087 '7, for 43 is according to this table the loss of gravity corre- sponding to a spirit indication of 9'6. It will be noticed that the tables do not exactly agree, for the spirit indication obtained from any given beer by the distillation process is always somewhat greater than that obtained by the other process. The reason of this is that when alcohol is added to pure water, the density of the mixture is lower than that of the water. An addition of 8 per cent., by weight, of alcohol, gives a mixture having a density of 986 '7, which is a loss of gravity of 13 '3; but 8 per cent, of alcohol in the same volume of water containing 10 per cent, of cane sugar, occasions a loss of gravity of only 12'92, or a reduction from 1036-47 to 1023'55. The degrees of spirit indication obtained are therefore less from the same absolute quantity of spirit in the sugar solution than in pure water. The sugar solution containing alcohol represents the beer, and gives the loss of gravity which the beer sustains by evaporation. On the other hand, the first mixture of pure water and alcohol represents the dilute spirits obtained from the same beer by distillation. The results are : Degrees of spirit indication Difference .. 13 -30 by distillation. 12 -92 by evaporation. 0-38 Thus the addition of a certain proportion of alcohol leaves the specific gravity of the mixture a little higher when the water contains sugar in solution. Fermentation demands the greatest care of any stage in the brewing process. Errors in malting or even in mashing, may be rectified ; but a slight error in the fermentation process is attended with very serious results. It was at one time the practice amongst the Scotch brewers to employ fermenting rounds only, and to cleanse from these directly into the casks. The fermentation was completed in the rounds. Under this system the process of fermentation required from one to three weeks. The wort was usually pitched at a low temperature, 10 or 11 (51 or 52 F.), and no more yeast was used than strictly necessary ; if the quantity first introduced failed to produce sufficiently active fermentation, the contents of the rounds were agitated twice daily, or a further quantity of yeast was added and well stirred in whilst the fermentation was going on. The yeast formed was not skimmed off, BEER. 407 and the fermentation was allowed to proceed until the ale was reduced to about one-fourth of the original gravity. The attenuation proceeded so slowly at the completion of fermentation as not to exceed half a pound a day. For some days previous to the drawing off, the head of yeast was not disturbed, and it floated on the surface as the ale was drawn off from below. This process is now modified by the adoption of " cleansing squares," into which the ale is dis- charged from the fermenting rounds, when within two or three degrees of the required attenuation. In the cleansing squares, the ale deposits its yeast, and becomes cool and is fined. From the squares it is drawn off into casks. Both the fermenting rounds and the cleansing squares are, in the best arranged breweries, fitted with attemperators, for reducing the temperature of the ale. The amount of refrigerating power required in these attemperators is small, for the fermenting rounds are almost always of very moderate capacity, seldom exceeding 40 barrels, and if larger, they are still shallow, and have large exposed surface ; consequently a considerable loss of heat by radiation occurs. The depth of the ale in the tuns is seldom more than 4 feet ; the wort is usually pitched at a temperature of from 11 to 14 (52 to 57 F.). The fermentation in the rounds generally occupies from four to six days, during which time the temperature increases to 21 or 22 (70 or 72 F.). The cleansing in the squares occupies from 24 to 36 hours. In Yorkshire, and the northern and southern counties of England, a system known as the stone or double-square system is very largely used. Fermentation is carried on in a somewhat deep square, divided at the middle of its depth by a horizontal partition in which is an opening. The worts are contained in the lower portion of the square, and the upper division is used as a chamber, into which the yeast rises through the opening. The beer is occasionally pumped from the lower chamber of the square into the upper one, where it becomes mixed with the yeast and again flows down into the lower compartment. The squares are commonly of stone, and the double square in which the fermentation proceeds is enclosed in another larger square, a space being left between the two into which water can be admitted for regulating the temperature. In the double square system, the beer is kept during fermentation at a temperature of about 13 or 14 (5U or 57 F.), and this temperature, when the desired attenuation has been reached, is reduced to about 56 by causing water to circulate through the exterior chamber and through attemperating pipes immersed in the liquid. This temperature is maintained during cleansing. In the large porter breweries, the fermenting tuns are of very great capacity, in some instances 1500 barrels. The usual capacity is between 200 and 700 barrels. These tuns are almost always of wood. Timber employed in the construction of tuns should be well seasoned, or the sap will mix with the wort and injure it. The round tuns are made of staves held together by hoops like those of a cask, the bottoms being supported by the beams on whieh the tuns rest. In the case of the square tuns, the planks are fastened together by bolts, and the sides are connected by cross stays stiffened by external beams. Square tuns have the advantage that they can be stowed with less wnste of room than round tuns ; but the round form is the best for wooden tuns, and should always be adopted where space permits. Fermenting tuns are generally fitted with attemperators. A common plan is to carry these pipes round the tun at a short distance from the sides, and to support them by brackets. Altemperators are sometimes fitted across the tun, and when thus fitted are very efficient, as the cooled wort descends and gives the warmer currents free access to the pipes. Uefore the plan of fitting the tuns with attemperating pipes came into use, the somewhat clumsy expedient of immersing in the wort casks filled with hot or cold water was employed for the purpose of accelerating or retarding the fermentation. The casks so used were termed "nurses," and are still used in some breweries. At Keid's brewery, the tuns, instead of being open at the top, are completely closed, with the exception of a small opening left for sampling; the carbonic acid gas evolved during fer- mentation is led off by descending pipes into a reservoir, where it is stored. From this reservoir it is drawn off at intervals into indiarubber bags, whence it is supplied to the Aerated Bread Company for the manufacture of bread on Dr. Dauglish's system. At some of the London breweries, large quantities of ice are used in summer time to lower the temperature during fermentation, as well as for preserving the yeast. In the ca;-e of the fermenting wort, the ice is used both to cool the air of the tun room and also the wort it.-elf ; in the latter case being commonly immersed in the wort, which is made of greater strength in order to allow for the reduction of gravity caused by the admixture of the melted ice. Where large quantities of wort are collected in the fermenting tun it would be more or less diffi- cult to complete the fermentation satisfactorily in these vessels ; and it is therefore the practice, amongst London brewers, after the fermentation has proceeded to a certain extent, to divide out the beer from the large tuns into a number of pontoons or cleansing rounds, having a capacity of about five to twelve barrels each. Stout, for instance, having an original gravity of, say, 32 Ib. a barrel, is usually pitched at a temperature of 13 or 14 (56 or 57 F.), the quantity of yeast added being about 1J Ib. a barrel. The attenuation is allowed to go on in the fermenting tuns until the gravity is reduced one-half. The beer is then divided out into the cleansing rounds, where the fermenta- 408 BEVEEAGES. tion is completed, the final gravity being for ordinary London trade 9 Ib. or 10 Ib. a barrel. With porter, the original gravity is usually from 20 Ib. to 22 Ib. a bairel, and the fermentation is con- tinued until the gravity is reduced to about one-third ; the quantity of yeast added is only about 1 Ib. a barrel. Cleansing rounds, squares, or pontoons, are covered vessels, each furnished at its upper side with an opening through which the yeast formed by the fermentation of the contained beer can escape. The rounds are completely filled with beer, and as there is a certain loss of liquid during the pro- gress of the cleansing, they have from time to time to be filled up, in order that the proper level may be maintained. The refilling is termed topping up, and it is performed sometimes by an, arrangement of ball-cock or similar self-acting valve, and sometimes by hand. The supply of beer necessary for maintaining the level in the pontoons is drawn from rounds placed at a higher level, and termed topping-up rounds, and filled with a well-fermented beer. The division of the beer amongst a number of small vessels greatly checks fermentation, and unless care is taken to push it sufficiently far in the fermenting tun, there is probability of the process being incomplete, and of the beer consequently remaining too sweet. The rounds being completely filled with beer, the yeast formed rises through the openings in the heads, and is conducted by spouts to troughs or backs in which it is collected. By this process the beer is gradually freed from the particles of yeast and glutinous matter held in suspension, which if not removed would keep the beer turbid- It seems probable that the composition of the water used in brewing affects to some extent the process of cleansing, for when the water contains a considerable proportion of compounds of lime, a double decomposition is set up with the salts present in the malt, and consequently in the wort, with the result of the formation of a lime salt, which is precipitated, and carries down impurities with it. Cleansing rounds were formerly made of wood, a common arrangement being that of casks placed on end in groups of four, with spouts leading from openings in the upper heads of the casks to a vertical spout carried down through the space in the centre of the group. From these rounds the beer is pumped through an attemperator or refrigerator to a settling tank, and thence into the vats. Cleansing squares constructed of slate are now largely used at the principal breweries. Slate appears to be the best material for the construction of cleansing squares, or for tanks for hold- ing cold beer. The slates forming the divisions between the squares are best so connected that no metal is exposed inside. The squares should be arranged in groups, and the slabs forming the divisions between the squares jointed to that forming the front of the group. The bolts securing the front slab may be screwed into nuts sunk in the division slabs, the hole containing the nut being filled in with putty. In some cases the slabs of slate squares are connected by angle-pieces, the heads and nuts of the bolts being tinned. The squares may be arranged in a series of double rows, having spaces between, into which the yeast is discharged. The lips, or short spouts by which the yeast issuing from the openings in the tops of the cleansing squares is discharged into the yeast troughs, may be of copper tinned, of tinned wrought iron, of wrought iron enamelled, or of cast iron painted and varnished. An objection has been raised to the employment of slate for cleansing squares, that it is a too good conductor of heat, and that the beer is subject to con- siderable atmospheric variations of temperature ; but this objection has no practical value. The fermentation of porter and stout at the London breweries is generally completed in cleansing rounds, but in some cases it is commenced and finished in squares holding from 170 to 320 barrels ; these squares are usually fitted with attemperators and with parachutes into which the yeast is skimmed. At the City of London Brewery, the fermentation of porter is commeoced in tuns holding 600 barrels, and completed in cleansing rounds having a capacity of 5J barrels each, or in hogsheads arranged in a similar manner to the Burton unions. For ale, it is usual to employ much smaller fermenting tuns than for porter, and frequently the fermentation is completed in these tuns. The tuns are sometimes fitted with small parachutes, by which the yeast can be removed and the fermentation checked. At Charrington's, the ale, after casking, is allowed to cleanse further, the casks being arranged on stillions or gutters, by which the yeast is received. The casks are filled up by hand. At Hoare's, the fermentation of the pale ales is completed in union casks, on the Burton system. At the City of London Brewery, the fermentation of ales is, in some instances, commenced in tuns of 140 barrels, and is completed in cleansing casks. At this brewery are copper fermenting tuns capable of holding 40 barrels each ; these tuns consisting of a copper vessel enclosed in an outer casing containing water. In these tuns the fermentation is commenced and completed, the temperature being regu- lated by water circulating between the tuns and their casing. The parachute consists of a kind of a copper funnel, having a stem which extends through the bottom of the tun. This stem is provided with a telescopic joint. By a lifting arrangement, the height of the parachute can be adjusted, so that its lip is slightly above the level of the beer in the tun ; as the yeast formed flows over into the parachute and down through the tubular stems, the cleansing proceeds in the same manner as in the cleansing rounds. As the cleansing proceeds, there is a certain loss of liquid from the tun, a 1 id the parachute has to be lowered from time to BEER. 409 time to maintain its level. Parachutes are sometimes balanced to float on the surface of the beer, and descend automatically. Usually, the top of the parachute has only a small area in proportion to the surface exposed by the beer, and the yeast is then skimmed into it. When fitted to ferment- ing squares, parachutes are sometimes made rectangular, and placed so that they extend across the squares. By the aid of parachutes the yeast can be removed from the tuns in a much more cleanly and convenient manner than by skimming. Another method of conducting fermentation is that known as the " Burton union system." In 1838, P. Walker, of Warriugton, invented the method of cleansing beers, this method having for its object the superseding of the necessity which then 307. existed for supplying by power or hand labour the place of the liquor discharged during fer- mentation, to keep the casks full ; and to prevent the yeasty head from being broken in upon the wort. According to his plan, independent passages were afforded for the flowing off of the yeast, and for the downward current of liquor, by which the cask or vessel was filled up. Another advantage was that the liquor for filling up could be intro- duced at the lower part of the cask, the yeasty head being left unbroken, and the attenuation allowed to go on in a regular and uniform manner. Fig. 307 is a transverse section of such an apparatus applied to casks ; a is a conical tube inserted in the bunghole of a cask ; from the upper part of this tube there rises the tube 6, termed the yeast tube, so that the yeast as it rises may be delivered into the trough c. A tube d de- scends through the conical piece a, nearly to the bottom of the cask, and this tube is at its upper end connected with a branch pipe which commu- nicates with the trough at the bottom. These tubes are the filling tubes, and by them the casks are filled and are kept supplied with liquor from the trough c, to compensate the loss of that thrown off during fermentation. The joint-piece by which the branch pipe is connected to the trough, is constructed with a plug like an ordinary cock, so that when the branch pipe is disconnected it can be turned downwards, and the flow of liquor shut off. The trough, which may be of any length required, is here shown suspended, whilst the casks are arranged on each side on sunk stillions. The malt liquor, in a sufficiently advanced state of fermentation, is run into the trough, from which it flows into the casks through the filling pipes, enough liquor being supplied to fill the casks, and to leave a certain quantity at the bottom of the trough. The liquor thus left, together with that which is carried off with the yeast and which subsides in the trough, serves to make up the loss during cleansing. The yeast, as already stated, rises up through the tubes 6, and flows into the trough c, and the fermentation and cleansing thus go on without attention until the completion of the operation, which is indicated by the yeast no longer flowing from the tubes. The system of fermentation followed at Burton somewhat resembles both the Scotch and the London systems, but differs from both. In the Burton system, as in the Scotch, the fermenting tuns are of moderate size, from 20 to 100 barrels ; instead of the fermentation being essentially a slow one, the wort is stimulated with large quantities of yeast, and the same result brought about as is caused by the great bulk of beer fermented in a single tun at the London breweries. The Burton, like the London brewer, after the fermentation has proceeded for a certain time, finds it desirable to divide out the beer, the usual course being to distribute it amongst the requisite number of union casks, in which the cleansing takes place. On the Burton system, the wort is pitched at a low temperature, say about 13 or 14 (55 to 57 F.), and receives a liberal allowance of yeast, of 4 Ib. to 5 Ib. or even more a barrel. For the best ales the original gravity of the wort is about 22 Ib. or 23 Ib. a barrel, and the attenuation is allowed to proceed until the gravity is reduced to 4 Ib. or 5 Ib. No yeast is removed from the ale whilst in the fermenting tuns, the cleansing being performed entirely in the union casks : in these the ale remains about a week before being discharged into the settling tanks. The fermenting tuns at the Burton breweries are in all cases of wood, and are fitted with attemperators. The tuns as a rule contain a greater depth of wort than those used in the Scotch breweries. At a number of the establishments at Burton, open wooden troughs are employed instead of pipes to distribute the wort to the 410 BEVERAGES. fermenting tuns. At Bass's, the fermenting squares are disposed in double rows, down each of which a pipe is led ; and from these pipes the squares are filled by the aid of open wooden troughs. At the Burton brewery, the fermenting rounds of a working capacity of 40 barrels are placed in groups of eight, and are filled from movable wooden troughs, which receive the wort from a main trough situated round the walls of the tun room. Each movable trough extends across four tuns, and these are tilled simultaneously through holes in the bottom of the trough ; the holes are fitted with plugs so that the wort can be shut off from any tun. Similar open troughs slung from the ceiling are also used at many of the Burton breweries to distribute the fermented wort from the tuns to the troughs of the union casks. The advantages of open wooden troughs as a means of dis- tributing the wort, are, that they are less in first cost than pipes, and may be kept thoroughly clean. They are, however, cumbrous, and are only applicable when the wort is supplied from higher level than the tuns. Union casks have generally a capacity of four barrels, and instead of being placed on the ground, as previously described, are slung on axles resting in bearings carried by a strong wooden frame. Usually the casks are disposed in double rows, each frame supporting from twelve to twenty casks. Above the casks is placed the yeast trough. When the casks are thus mounted, the method of employment is as follows: The ale to be cleansed is pumped, or run, into the yeast trough above the casks, and the plugs which close the pipes leading from the bottom of this trough being removed, the liquor runs down into the casks. When these are filled, the plugs are inserted, and the swan necks are thus left as the sole vents through which the yeast can escape. The yeast troughs belonging to the union casks are in almost all instances fitted with attem- perating pipes. The attemperating pipes of yeast troughs are sometimes so fitted, that by means of cords passing over pulleys fixed to the ceiling, they can be lifted up clear of the troughs, when the latter have to be cleaned. The union casks also are fitted with attemperators. A good arrangement consists of a hollow brass plug screwed into a suitable mounting on the top of the cask, this plug having two nozzles, which respectively communicate each with one of the tinned copper pipes extending from the plug into the cask. These pipes are connected at their inner ends, and a current of water can be made to enter at one nozzle, flow through the corresponding pipe, and return by the other pipe to be discharged by the second nozzle. The nozzles are respectively connected by flexible tubing to cold water and return pipes led along the sides of the yeast trough. These attemperators can be readily removed, and the holes through which they were inserted being closed by plugs, the cask can be rotated for cleansing in the usual way. To reduce the labour incidental to the disconnection of the casks lor cleaning, the plan of filling and feeding each cask through one of its axles has been introduced. At one end of each cask, the axle or trunnions, cast in one piece with the cast-iron cross fixed to the head, is hollow, and is fitted with a brass bush secured by a nut. At the inner end, the brush or tube is made conical, so that it fits tightly into the hole in the head of the cask, whilst, at the other end, it has a spherical bearing formed on it, which fits into a corresponding seat at the end of the branch pipe from which the cask is filled. The spherical bearing and its seat are held in close contact by bolts, the nuts of which exert their pressure through spiral springs. By this means a joint is obtained, that, although perfectly tight, does not interfere with the rotation of the cask. The main pipe running along each range of union casks, communicating both with the feed reservoir and with the fermenting tuns, is furnished with cocks, by which the supply from either source can be regulated. Each branch pipe is also furnished with a cock for regulating the supply to the particular cask to which it belongs, and each branch is also formed for a portion of its length of flexible tubing to enable the lower end to be readily disconnected. For turning the casks, spur wheels and crank handles are provided. The " Untergahrung," or system of bottom fermentation followed by the Bavarian brewers, differs materially from any adopted in this country. The object of the Bavarian process is to completely clear the wort of gluten, and, by removing the oxidizable matters, render the beer incapable of being soured by even a prolonged exposure to the atmosphere. To effect the separation of the gluten, the Bavarian brewers, instead of adding ordinary yeast to the wort, mix it with the peculiar kind of deposited yeast termed "unterhefe." The fermentation is effected in comparatively shallow backs or squares, placed in cool cellars, where the atmospheric temperature is not allowed to exceed 8 to 10 (46 to 50 F.). The process requires three or four weeks, the carbonic acid gas being disengaged in very minute bubbles, that carry up a mere film of froth. The insoluble gluten or yeast is deposited at the bottom of the fermenting vessels as a viscid sediment, the unterhefe. This deposited yeast is gluten oxidized in a state of eremacausis, or slow combustion, whilst the ordinary surface yeast is gluten oxidized in a state of putrefaction, arid the former, when added to wort at a low temperature, is incapable of causing the direct oxidation of the gluten dissolved in the wort, although it possesses the power of causing the transformation of the saccharine matter into alcohol and carbonic acid. In the Bavarian process, the oxidation of the gluten has to be effected by the action of the atmosphere, and the large area exposed by the fermenting vessels, together with the freedom of the surface of the beer fiom any protecting layer of yeast, BEER. 411 gives every facility for this atmospheric action. It might be supposed that the atmospheric action which causes the Bavarian beer to deposit its gluten would also induce an acetic fermentation in the wort. Such an occurrence is prevented by the low temperature maintained in the fermenting rooms, a temperature below that at which acetic fermentation of alcohol will take place. The unterhefe employed by the Bavarian brewers may, by some expenditure of time and trouble, be prepared from ordinary yeast. If some of the latter be added to wort at the low temperature of 8 to 10, and a slow fermentation allowed to take place, the yeast will be partly deposited and partly carried up to the surface. If this deposited yeast be collected to produce another fermenta- tion, this will result in the deposition of a bottom yeast still more resembling unterhefe ; and by repeating these operations, unterhefe is at length obtained. It is in very many instances desirable that a similar arrangement should be provided, in other countries than Bavaria; for during the summer months the high atmospheric temperature pre- vents, to a great extent, successful brewing of the best kinds of malt liquor, and loss of time is occasioned to the brewer. With a view of affording a more perfect control over the process of fer- mentation, Barclay Walker, of Warrington, designed an atmospheric tun-room attemperator. It consists of a fan, by the aid of which a supply of air is forced to traverse a number of flattened tubes immersed in cold water, or surrounded by ice or a freezing mixture ; the air, after being thus cooled, is led off by pipes extending over the range of tuns in the tun room. From the pipes, branches are led down into the tuns, these branches being furnished at their lower ends with perforated roses, which distribute the cold air a short distance above the surface of the wort. Each branch is fur- nished with a slide, so that the supply of air to each tun can be regulated. By this arrangement, the temperature of the air above the surface of the fermenting wort can be kept at that point which produces the best results, and a command over the process is given which cannot be obtained under ordinary circumstances. Where yeast cannot be got by exchange, it may be originated from a mixture consisting of 14 Ib. of grated potatoes, a similar quantity of molasses, coarse sugar, or honey, mixed with 3 gallons of water at a temperature of 21 to 24 (70 to 75 F.). This mixture should be set in a warm place until it ferments, and then mixed into three times its quantity of fresh first wort from the mash tun. This yeast is often made by distillers, and is known under the term of " bub." When the brewer is compelled to use bub, he ought to employ it on a small brew, to raise barm for future brews. The quantity proposed will ferment 40 or 50 barrels. It may be here recapitulated that in the best practice good brewing depends upon careful malt- ing, so as to have the malt always in the same condition of freely yielding the extract required from it. Careful curing of the malt on the kiln at the time of drying, and storing it in suitable backs, so as to retain the properties acquired in the kiln. To keep these backs of a size that when opened will allow of their contents being used, before the malt loses its curing, or suffers the slightest decomposition ; the only alternative being to re-cure the malt so that it may be sound when it comes to the mash tun. In mashing, to wet the malt first into a thick mash within the point of the ultimate temperature, so far as to allow the variations in the heat of the malt under use to expend itself within the given ultimate temperature, and thus prevent the setting of the mashes, and the passing to the fermenting tun of pasty, unconverted materials that may afterwards decompose in the beer. This wetting process should produce a homogeneous temperature of 65 (150 F.), and immediately after this wetting hotter water should be turned on, and the mashing rakes started to bring the temperature to 69 (156 F.). The mash, after standing one hour and three-quarters, should have the sparge temperature regulated, to keep the goods at 6b for two and a half to three hours from the time of setting the tap ; and if the goods are not extracted by this time, the water must be lowered in temperature 10 or 14 (20 or 30 F.) or more, if necessary, to bring the goods in the tun to 65 by the time the extraction is complete. In mashing, time and temperature may be considered nearly synony- mous terms; preponderance of heat should be compensated by reduction of the time during which the goods are exposed. In sparging, if the goods heat rises to 70 (158 F.), or even 71, the sparge-water temperature should be lowered for the first half hour, or for a whole hour, sooner than the three hours given as a standard period of high heat exposure, so that the goods will have been brought to 65 at the end of the process. If second mash and a sparge be the method followed, the second mash heat may be 69, like the first, but the sparging to follow ought to lower the mash apparatus gradually to 65 at the end of the mash ; and if a third or fourth mashing muat be taken, neither ought to make the goods over 65. Vatting and Fining. It was formerly the practice of the London brewers to keep immense stocks of their porter in store for eighteen months or two years. The store vats, some of which were of enormous size, were made of well-seasoned oak strongly hooped, and their heads were covered with sand, so as to exclude the air as much as possible. At the present time, the practice of vatting beer for long periods is not followed. At numerous breweries, it is the practice to pump or run the beer from the cleansing rounds to 412 BEVERAGES. settling tanks or racking squares, and after allowing it to deposit any floating matters, to draw it off direct into casks. In casking pale ale, from Ib. to 1J Ib. of fresh choice hops a barrel is added; these hops materially assist in keeping the ale, and also impart to it a fine aroma. Stock ales also recejve about 1 Ib. of hops a barrel when casked. The pale ale should be kept in cask at least six months before being consumed, and if well brewed it may be kept from twice to three times that period with advantage. London porter now seldom remains in a vat more than a month, and as a rule it is stored only for a day or two. The change effected in beer by storing it in close vessels appears to be due to an insensible fermentation, which goes on for a considerable time, resulting in the impregnation of the liquor with carbonic acid gas. Ure considers that the quality of the beer never remains stationary when in the store vats, and that from the moment it ceases to improve it begins to deteriorate by acetic fermentation. To clarify beer, finings, made usually from isinglass, are frequently employed. Finings are prepared by placing the isinglass, or other materials, such as sole skins or sounds of cod-fish, in a vessel, and covering it to a depth of 5 or 6 inches with vinegar, or sour old beer. When the isinglass has softened and swollen up, so as to absorb this liquor, a further supply of sour beer is added, and the mixture well stirred up, the process being repeated until the whole becomes of a uniform consistency. In some breweries this pulpy liquid is mixed with weak bright beer, and strained through a hair sieve ; whilst in other cases it is thinned with the bright beer, and then allowed to become clear by depositing the insoluble matters in settling tanks. The final gravity of the finings should be about 1 '025. In using finings, they should be first mixed with a large bulk of the beer to be clarified, and after agitation the mixture should be poured into the main body, and well stirred in. After this the beer should be allowed to stand about twenty-four hours, when the impurities will be deposited. Ure considers that the clarifying action of isinglass is due to the tannin of the hops combining with the fluid gelatine, and forming a flocculent mass which envelops the muddy particles of the beer and carries them to the bottom as it falls. Isinglass varies considerably in value, and it is important that brewers should have a ready means of judging of its quality. The best isinglass consists almost entirely of gelatine, and does not contain more than 2 per cent, of substances insoluble in water. One method of testing isinglass consists in placing a known quantity of it in water, boiling and weighing the insoluble matters that may be separated by straining the solution. Another test consists in steeping the isin- glass in spirits of wine, in which gelatine is insoluble, and then adding a few drops of tincture of galls. If a deposit is formed, it shows the existence of impurities ; whilst if the liquid remains clear, there is a strong presumption that the isinglass is of good quality. A practical and simple method of testing the value of isinglass or of other materials used in the manufacture of finings consists in dissolving a given weight of the isinglass to be tested in a fixed quantity of sour beer, and then pouring the solution into a funnel, the neck or spout of which is carefully bored out to a known diameter of about ^ inch. The solution is allowed to flow from the funnel into a graduated glass measure for a period of time measured by a sandglass, and the quantity of solution which has run through in this time indicates the quality of the isinglass. The higher the quality, the thicker will be the solution, and the more slowly it will flow from the funnel. Graham remarks on the general process of brewing, that the simplest arrangement is to carry out the fermentation through its first stages in the fermentation square or round, and afterwards to complete the secondary fermentation in settling squares. This method is less wasteful and is very efficient. But in carrying out such a process exceeding care must be taken that in the settling square the beer should be covered with a layer of carbonic acid, or in other words the gyle must be run off into the settling square before it is become dead. Graham further remarks that a rapid pro- cess is not always attended with equally excellent results, and those specially engaged in preparing store ales must bear in mind that it is quite impossible for them by any rapid driving process to produce an ale of the highest excellence in a short space of time. With proper treatment of store ales, it occasionally happens that they become sour, and in such cases it is necessary to employ materials that contain quick lime or other acid-neutralizing agent. In bottling ales, it may be necessary for the bottler to carry on the German system of slow feed- ing, and as it is illegal to employ sugar for the purpose, the brewer should be called upon to supply a few barrels of wort excessively rich in sugar, and containing but little of the malt extract. This wort ought to be very highly charged with bisulphite of lime. When the store cask is fed with a little of this wort, a small quantity of bisulphite introduced into each barrel will do good rather than harm, and there is thus the advantage of slowly feeding the store cask and not in any way running counter to the excise laws. If beer containing yeast cells is heated to a temperature of 50 to 60 (120 to 140 F.), the yeast cells are killed. Graham proposes a process based upon this discovery of Pasteur's. The beer should be run from the store cask and corked with a paraffined cork, that is with a cork saturated with parafBn wax, by which the loss that occurs from the cork giving insufficient protection against BEER. 413 pressure is avoided. The next process is to destroy the ferment in the ale itself, because however bright the ale may be, there are always floating on it minute yeast cells. If the ale were placed in a bottle and heated to a sufficient temperature to destroy these yeast cells, ale that did not contain sufficient carbonic acid would be unpleasant to drink because it would not effervesce. It is necessary therefore for the bottler to charge each bottle with carbonic acid ; and this may be done by merely allowing the bottles to remain until there is produced in the ale enough carbonic acid by subsequent fermentation a process occupying two or three weeks. When the ale has thus obtained sufficient carbonic acid, it must be heated to about 60. But if the bottler be pressed for time, and the ale is very flat and is required for immediate export, carbonic acid may be forced into the ale by an ordinary carbonic acid apparatus, and the bottles afterwards heated. In heating Burton ale up to 60, there is a lessening of the amount of haziness due to albuminous matter, and with Edinburgh ale there is a very distinct improvement in the brilliancy. In the public-house and restaurant, beer is sometimes fed with molasses or is rendered sparkling by the use of carbonic acid apparatus. The racking of beer is an operation nearly obsolete in England and Scotland, and, when followed, is employed only from the necessity of supplying small purchasers. As a rule, racked beer becomes stale and unpalatable before the barrels are emptied. But any attempt to deal with porter without racking would prove a failure, as its lees are very bitter and nauseous. The turning over of these lees when the casks are moved to be sent out is certain to impair the flavour. To produce the head, which is an essential feature of draught porter, as without it the beer is unpalat- able, the porter is mixed, previously to being sent to the consumer, with new unfermented wort, and the mixing is most conveniently effected on the racking system. The mixing material has technically the name of fillings, and is wort taken from the cooler at the same time that the fer- menting vat is filled. This wort is put into open-ended puncheons, and lightly barmed with a quart of yeast a puncheon, to prevent spontaneous fermentation until required for use. The pun- cheon first required for use is given extra barm in the quantity of about half a gallon, and all the puncheons, in their successive order of use, are given as much additional yeast on the night before they are required as will make them ready for the next day's use. If the fillings vessels are in underground cellars, their temperature will not need raising artificially, but in winter, if exposed, the temperature of small quantities will become too low to form a head without pan-heating to 18 or 19 (64 or 66 F.). In Ireland, where a brisk porter is in demand, small service vats are filled in the night with proper proportions of new and old porters, ready for the next day's demands. A similar procedure is followed by the London retailers. Fillings are used principally for draught porter, and the allowance ranges from 10 to 20 per cent., as the stock is new or old. The best draught porter is obtained from matured, well-attenuated old porter, mixed with 15 to 20 per cent, of rich unfermented raw wort or fillings. Cellaring in England, as compared with Continental storing, has a disadvantage in the want of ice ; and the ice machine, the substitute for ice, ought to be in every brewery, so as to afford the brewer the means of readily lowering the temperature to a point of comparative safety. Ice itself is not a necessity ; water at 4 (40 F.) is fully effective, and not very costly to produce. It would be advantageous to employ some special means of cooling transit casks before they are sent out in the hot weather, as their contents, however good before leaving the brewery, often refuse to fine, and even if they do fine, become tart. Beers for use at the end of the season should be deposited in the cellars of the publican in the spring, before the frost has left the atmosphere. Such beer ought to be set apart, and the beers required up to the commencement of August taken in the meantime from the brewery. Beer deposited in a cool state in a cool cellar with the publican, and not disturbed, has the advantuge over that coming direct from the brewer's cellar, that it is not remixed with its yeast deposits, and then heated by the summer's sun. All beers ought to go out to the consumer when cleansed, and be used in the first fining down, for once fined in the brewery, and turned over in summer, and heated in transit, it is improbable that beer will fine again before acetification sets in. Brewers on this account should not set up store in spring or summer, after the hot weather has commenced, but the brewing should stop on the first appearance of heat. It is very bad policy to brew in May or June the stock of beer to go out in August or September, with risk of souring, when beers can be brewed as well at the end of summer as at the beginning, if the malt is in order. A good brewer will clear out his stock in July or August. It is advisable iu cellaring to send out the best beers first, as in waiting to get rid of inferior beers both may be lost. Export beers are made of gravities from 40 upwards, rising in stages of 5 to 115. Exports so low as of 0'40 are very rare, and the principal article of so low a gravity is a light porter for storing in the West Indies and in Nova Scotia. Its specific gravity is generally 47, and it is made of a well-dried malt, one half pale the other half amber and black, and hopped with 12 Ib. of good Bavarian or American, double boiled. It is sent out in hogsheads from London, Edinburgh, and Glasgow. The usual export beers commence at 0'50, and generally average 0'55, O'GO, and - 6G, 414 BEVERAGES. Bottled beer generally has a gravity of 0-70. Beer for bottling should be kept nine to twelve months at least, and should be brewed from October to May ; it is laid down as an imperative rule that such beer should undergo a summer's heat and autumn's fermentation in cask in England before bottling to be sent abroad. The most economical method of bottling is to run the store hogs- heads and butts off, dry to the hop, into vats containing about two days' supply, and there fine it down a week before it is wanted. These vats ought always to be well sulphured before filling. Casks for export are always now steam seasoned, being set on end with the steam jet in the tap- hole ; the bung-hole is filled up with an old shive having an open spile-hole in it by which to learn the pressure of the steam. This method is preferable to that of steaming casks on their sides through the bung-hole, a system that is the cause of breaking large quantities of bung staves. Old casks should not be steamed, but should be filled with water to which a handful of quick lime is added. E. S. Cider. (FR., Cidre ; GEB., Apfelwein.) Cider is an alcoholic beverage made by fermenting the juice of the apple. It is largely prepared in different parts of England, France, and the United States, where the fruit is chiefly cultivated. Cider, like wine, is the product of the juice of a sweet fruit , it contains alcohol, extractive matters, acids, and salts, and it possesses a flavour and aroma which are agreeable to nearly every taste. Cider, as usually made, contains a much smaller proportion of alcohol than most wines, and a much larger proportion of gummy and nitrogenous substances ; the acids, while they impart to it refreshing properties, are more enfeebling to the system than tartaric acid; its taste is not so pleasant to the palate as that of wine, and its effects are not nearly so powerful. The nitrogenous substances, although making the drink more nutritive, render it liable to decompose and be spoiled. In spite of the many different opinions on this subject, cider, if carefully prepared, is a very excellent beverage, and second only to good wine ; it possesses many qualities which render it in many respects greatly superior to beer. Unfortunately, however, both in England and abroad, so liitle care is bestowed upon the preparation of this drink, and such antiquated and faulty methods are employed, that the ordinary cider of commerce is a far inferior article to what might be made by processes based upon scientific principles and conducted with more care and discrimination. The inferior quality, made from unripe fruit and not carefully fermented, is decidedly unwholesome, and its consumption liable to cause colic. The best cider contains from 8 to 10 per cent, of alcohol ; and the ordinary varieties, from 4 to 6 per cent. The former kind is made at the present day in Normandy, New J ersey (U.S.), and Herefordshire, the remainder being chiefly made in Devonshire and Somerset. The following table represents an average analysis of the apples and pears used in cider- making : APPLES. PEARS. Unripe. Ripe. Mellowed. Unripe. Ripe. Mellowed. Water 85-50 83-20 63-55 86-28 83-28 67'73 4-90 11-00 7-95 6-45 11-52 8'77 Vegetable matter 5-00 4-01 3-00 2 - ll 2-06 2-00 3-80 3-17 2-19 2-07 1-85 2-62 Albumen Acids (malic, pectic, tannic, &c.) 0-10 0-49 0-50 0-50 0-06 0-60 0-08 0-22 0-21 0-13 0-23 0-65 100-00 100-00 76-10 100-00 100-00 76-85 The loss of 23-9 per cent, in mellowed apples, and of 23-15 per cent, in mellowed pears, is due to the evaporation of the water and the decomposition of a portion of the organic matter, especially of the sugar, which is converted into alcohol and carbonic acid. The sugar which is con- tamed in the ripe fruit is sufficient to furnish from 3- 12 to 7 "34 per cent, of alcohol by volume. The 'keeping qualities of the fermented juice of apples and pears depend upon the presence of a sufficient quantity of alcohol and sugar, and upon the absence of all nitrogenous, fermentable matter, especially of aromatic principles, which are abundant in the unfermented juice. Unless alcohol be present in the fermented juice in the proportion of 18 or 20 per cent, by volume, the latter is certain sooner or later to undergo acetous fermentation. Now, ciders made from the juice of the apple alone, without any addition of water, cannot possibly attain a higher richness than from 3 to 7 per cent, of alcohol, which gives an average of 5 per cent, for common ciders, or only one-fourth of the proportion required to ensure its keeping. From this it is clear that the alcohol alone will not prevent the drink from undergoing acetous fermentation, but that the absence of any fermentable principle must also be ensured. In order to render the fermented CIDER. 415 cider preservable, the apple juice should, at the time of fermentation, always stand at 8 or 10 B. But since this proportion of sugar will not produce a sufficient quantity of alcohol to prevent an acetous fermentation from taking place, it should be considered only as an auxiliary to certain other precautions, to be treated of later. It may be assumed, from what has been already said, that 5 per cent, of alcohol is a sufficient quantity, provided that the causes of after-fermentation have been carefully removed, but that a larger quantity, if it can be obtained, is much to be preferred. Besides increasing the density of the juices, and thus augmenting the proportion of sugar con- tained in them, there is another method by which the saccharine richness of the " must " may be considerably raised, and this method is by far the best, notwithstanding the time which it occupies. It consists in gradually replacing the ordinary and less sweet varieties of apple by those which are much richer in sugar, and this is by no means impossible, or even difficult. It is true that there exists still a deep, but utterly unfounded prejudice against sweet apples among cider-makers ; this prejudice, however, may be easily combated, since it is opposed to the first principles of fermentation and of cenological science. Unless the fruit employed for cider-making contain a proper quantity of astringent substances, it is true that the product obtained from it is subject, though only after an incomplete or careless fermentation, to the annoying accident termed " viscous fermentation." It ia owing to this that cider, made by the usual faulty process, from sweet apples, is more liable to alteration than that made from apples containing less sugar. But this objection loses all its force when the process has been carried on upon sounder and more correct principles, and hence it is that cider-makers have, in thtir ignorance, been compelled to make use of fruit containing but little sugar, and thus to produce cider insufficiently rich in alcohol to be either agreeable to the taste or capable of resisting acetification and other vexatious alterations. It should be remembered, that the more sugar any fruit contains, the more alcohol it will yield, and the smaller, con- sequently, will be the chances of any subsequent alteration of the product, provided that certain substances favourable to alteration have been carefully eliminated. Although it has been stated that it is advisable to employ only the sweetest apples obtainable, the cider-maker must be cautioned against excluding those varieties which are rich in tannin, or the astringent piinciple. He should always have in view the cultivation of a fruit containing the maximum of both sugar and tannin. Apples and pears, which are at the same time very sweet and very bitter, furnish the elements of a beverage which will be rich in alcohol, i.nd which can be kept for a very long period without degenerating. Sugar yields alcohol in proportion to its own abundance, and the tannin, by partially or entirely removing the albuminous matters, effectually protects the fermented drink from being spoiled by after-fermentation. Referring to the analysis given above, the average composition of the fruit in all three stages will be found to be represented by the following figures : Water 77'40 , Albumen 0'22 Saccharine matter 7 '95 Gum and mucilage 2 '70 Malic, pectic, tannic acids, &c. . . 3-83 92-10 By removing the water, and leaving the fruit perfectly dry, the following figures are obtained : Grape sugar 64 '26 Vegetable tissue 17*53 Gum , 12-33 Albumen 2-92 Malic acid, &c 2-92 99-96 From these figures, it will be seen that by subjecting the fruit to a process of desiccation it is possible to give to the product any alcoholic strength desired, and the necessity of improving the must by the addition of sugar or glucose is thereby entirely avoided. If it be admitted, for example, that ripe apples contain 1 1 per cent, of sugar, this corresponds to 8 per cent, of pure alcohol by volume, and it will be easily possible, by the addition of dried fruit, to increase the strength to 10 per cent., which is about that of the common French wines. It requires 16 per cent, by weight of sugar to give, theoretically, 8 per cent, by weight, or 10 per cent, by volume, of alcohol, and such a quantity of dried fruit as will bring the product up to, at least, this strength should be added to the must. This would mean, on an average, 5 per cent, of sugar to be added, which would correspond to about 7 Ib. of diied apples. Since the desiccation is never by any means complete, as assumed above, this quantity should be doubled, in order to afford to this must an alcoholic richness of 9 to 10 per cent., which strength would greatly improve and ensure the preservation of the finished product. In order to bring into prnctice the plan just described, it is necessary only to keep a large stock of dried fruit of the best varieties, and to add this in proper quantities to the unfermented juice ; by this means, cider of the very best description, and capable of being kept for a great number of years, may be easily prepared. The same result might doubtless be obtained by concentrating a 416 BEVEEAGES. quantity of the must to the consistency of a syrup and adding it to the ordinary must ; this method would probably be more easily practicable and more economical than the one just described. When the juice of the apple has been extracted by the best method possible, and its active fer- mentation has been conducted for a sufficient length of time and at a proper temperature, it only remains to remove all foreign matter, whether suspended or settled down; to clear the cider thoroughly from all soluble albuminous matter, whether coagulable or non-coagulable ; in short, to submit it to a complete defecation, in order to allow of its being kept without fear of spoiling. This should be effected by drawing it off carefully after the suspended matters have settled down ; clarifying it carefully by the ordinary methodical processes of refining ; guarding it against the adverse influences of air and warmth ; and by exercising as much care over these processes and over the product itself as is customarily bestowed upon wines from the grape. Careful attention to all the points here enumerated is all that is required to produce a really good beverage, and one that will not be inferior to many wines, instead of the crude, harsh-flavoured drink that is commonly sold under the name of cider. Before pointing out the method of putting into practice the improvements suggested in the fore- going paragraphs, it is desirable to describe the old-fashioned processes, which are still generally followed. Common Method of Cider-making. The apples used in cider-making are just, or nearly, ripe when gathered, a state that may be recognized by their appearance and odour, or by the blackness of their seeds. Those which fall, or are gathered before maturity, are laid aside for a week or ten days, in order that they may become mellow ; any which may have become rotten during this time are carefully picked out and rejected. In some places, it is the custom to preserve all the fruit, whether ripe or unripe, for a certain length of time, varying from a week to six weeks, care being taken not to let the apples lie until they become pulpy, as in this condition they are wholly unfit for cider-making. They are next ground in a mill, in order to break up the cellules and set free the saccharine juice. When much fruit is being dealt with, the old-fashioned horse-mill is still in vogue. It consists of a circular stone trough, in which a large stone wheel is made to revolve on its edge ; the apples are poured into this trough and crushed by the wheel, which is turned by a horse, or by two horses, much in the same way as the tanners grind their bark. When about half ground, a little fresh water is added to the mash. In such a mill, three or four hogsheads of apples may be ground in the day ; but the cider has usually an unpleasant taste, acquired from the rinds, stems, and seeds of the fruit, which in these mills are much bruised. Another and better mill consists of two cast-iron, fluted cylinders, one of which is turned by a handle and communicates its motion to the other. These are fixed in a wooden case, and the apples are fed in through a hopper placed directly above. The crushed fruit should be passed twice through the mill in order to extract the whole of the juice. This mill will crush fruit enough in one day to make nearly twenty hogsheads of cider. The next operation is to press the crushed fruit, which is performed after it has stood for about twelve hours, at the most, in a wooden tub or cistern. Here, fermentation commences, and the breaking up of the cells takes place, by which the subsequent separation of the juice is much facilitated. The crushed pulp is then placed in hair-cloth or coarse canvas bags, and Allowed to drain into suitable receivers, after which it is subjected to a powerful pressure in the cider-press, a large screw-press. The juice which runs away is at first foul and muddy, but is afterwards as clean and pure as if filtered througli paper. It is common to throw away the remaining thin, dry cakes of pressed pulp, as useless, or to feed pigs with them ; or sometimes it is ground a second time with water and pressed for an inferior kind of cider, which is very weak, and must be drunk at once, as it will not keep. The first runnings may be strained through a sieve ; the whole is then placed in large casks, filled to the brim, where it soon begins to exhibit tumultuous fermentation ; the froth or yeast which collects upon the surface of the fermenting liquor is always removed. A bung-hole affords a sufficient exit for the carbonic acid gas disengaged. The fermentation is usually conducted in airy sheds, where the warmth is scarcely greater than that of the open atmosphere. If the liquor be much agitated, the process may las-t only one day; but when allowed to remain at rest, the fermentation commonly goes on two or three days, and even five or six. No ferment is used. The liquor is then racked or drawn off from the lees, and put into fresh casks. A fresh fermentation usually commences after racking, and if it becomes violent another racking is often performed in order to check it, in consequence of which tlie same liquor may require 1o be racked afresh five or six times. It is customary to fumigate the cask before running in the liquor by burning inside it a strip of linen coated with sulphur ; this is kindled at one end and lowered into the casks through the bung-hole, the bung being immediately replaced. The object of this operation, called " stumming," is to prevent the liquor from " fretting," or undergoing the after-fermentation already mentioned. The casks containing the cider are then stored in a cellar, barn, or other cool place, where a low and regular temperature can be maintained, and left to mature or ripen. By the following spring, the cider is considered fit for consumption and bottled or re-racked for sale. CIDER. 417 Cider is made of three different qualities: rough, sweet, and bitter. In the manufacture of the first or lowest quality, very little trouble or care is taken. The rougher the drink, the farther it will go, and the rnora acceptable it is to the working man. A palate accustomed to a sweet cider would judge the rough cider of farmhouses to be a mixture of vinegar and water, with a little dissolved alum to give it roughness. The method of producing this austere liquor is to grind the fruit in a crude, unripe state, and subject the juice to a full fermentation. For sweet cider, the sweeter fruits are chosen and ground in a perfectly ripe state, the fermentation of the juice being, also, checked before completion. To produce the bitter cider, particular varieties of fruit must be used, and the season in which it is matured must be taken into consideration. The temperature at which the fermentation is conducted is a matter of much importance, though it very rarely receives from cider-makers the attention it requires. The juice, when expressed from the fruit, is left in a cool place, at a temperature of about 10 or 12. When, as is frequently the case, the juice is permitted to stand in the full heat of the autumn sun, much of the alcohol undergoes acetous fermentation, being thus converted into vinegar, to which the unpleasantly rough and acid taste of common cider is entirely due. These properties are especially characteristic of the cider of Devonshire, in which county but little attention is paid to this part of the process ; the result is that the cider will keep, at the most, only four or five years, whereas, that made in Herefordshire and Worcestershire, where the fermentation is more carefully conducted, can be kept for a much longer period. Before bottling, it is customary to improve the flavour or strength of weak cider, and for this purpose there are many plans in use. The want of strength is supplied by brandy or any other spirit, in sufficient quantity to prevent acetous fermentation. To supply flavour, an infusion of hops is sometimes added, which is said to communicate an agreeable bitterness, and at the same time a fragrant odour. The want of colour is sometimes supplied by elderberries, but more generally by burnt sugar. Isinglass, eggs, or the blood of oxen are often made use of to refine and brighten the liquor. The proper time to bottle cider depends greatly upon the quality of the liquor itself; it can seldom be bottled with propriety until a year old, sometimes not until it is two years old. It should have just acquired its utmost degree of richness and flavour in the cask ; and this it will preserve for many years in bottles. The liquor called "ciderkin" is made of the marc or gross matter remaining after the cider is pressed out. To make this liquor, the marc is put into a large vat, with a proper quantity of boiled water which has just become cold ; the whole is left to infuse for forty-eight hours, and then well pressed. The liquor which runs out from the press is immediately tunned up and stopped ; it is fit to drink in a few days, and serves in families instead of small beer. Improved Method of Cider-making. When the juice of any fruit is required for use, it is a matter of much importance that as complete an extraction be made as possible, since the economy of the entire process depends primarily upon this. It is not effected easily, even by maceration, unless the vegetable tissue has previously been thoroughly disintegrated, in order to break open the minute cellules of which it is composed, and thus to set free the saccharine juices held in them. The more carefully this disintegration is conducted, the more easy is it. by mechanical means, to effect a thorough extraction ; and an incomplete disintegration not only leads to very poor results, but also renders it necessary to employ a process of maceration in order to obtain all the sugar, instead of submitting the pulp to the action of a press, which is a far quicker and more economical method. To obtain, therefore, the maximum yield of juice from his fruit, the cider-maker should consider it an indispensable condition that tke apples be thoroughly crushed or ground before subjecting them to pressure. Many different forms of apparatus are employed in crushing the fruit. The ordinary horse-mill, in which it is ground to a pulp by means of a circular stone wheel, described above, presents many disadvantages, to all of which the manufacturer still persists in shutting his eyes. It requires an enormous amount of labour, and it consumes far more time than is necessary. Besides this, in such a mill, the pippins or seeds of the fruit are crushed as well as the pulp, a contingency which ought to be carefully guarded against. The seeds of apples contain 25 per cent, of a colourless fixed oil, which is not absolutely injurious ; but they contain also a minute quantity of a volatile essence, closely resembling, if not identical with, the oil of bitter almonds. This oil, if present in cider in any quantity, effectually covers the flavour of the drink, and exerts a most powerful action upon the nervous system, and particularly upon the brain. To its presence are probably due the prolonged intoxicating effects and the serious disorders which follow excessive indulgence in this drink. The breaking up of the seeds does not render the cider more alcoholic, but it adds greatly to its intoxi- cating effects, and should therefore be avoided in every possible way. Another mill, used only in England, and much to be preferred to the one just mentioned, con- sists of two cylinders, having a number of knife-blades attached to them ; these move in opposite directions, and reduce the fruit, which is fed in from above, to small slices. The apples, thus Divided, fall between two other cylinders, made usually of granite, which crush them to a pulp of 2 E 418 BEVERAGES. more or less fineness, according to the distance apart at which the cylinders are' placed. By thia means, the fruit is prepared for the press without any danger of bruising the seeds and stems. A machine, preferable to either of the above for crushing apples, was devised by Berjot, and is now used in France ; it is shown in Figs. 308 and 309, from which a good idea of the method of working will be gained. The two vertical wheels are of granite ; they work in opposite directions, and may be regulated to stand at any required distance from each other. The apparatus is worked by horse-power, and can be made to crush 5 bushels of apples a minute. One of its chief merits is that there is no iron used in its construction ; contact with this metal is very injurious to the quality of the juice. It may be used for a variety of other purposes besides crushing fruit; it occupies but little space, and, by reason of its extreme simplicity, it is very readily repaired. Manual labour may be employed to work it if desired. This mill is decidedly the best at present in use, and we recommend it, above all others, to the cider-makers of this country. The fruit having, by the above method, been reduced to a kind of pulp, and a large quantity of its juices expressed, the next operation is to extract, if possible, the whole of the remainder. If thia extraction were completely effected, 100 Ib. of apples would yield nearly 98 Ib. of must for fermen- tation. Nothing like this qtiantity is, however, obtained at present, the deficiency being made up by the addition of water. It is true that no apparatus has ever been devised by which it is possible to extract the whole of the saccharine juices ; but it is easily possible, with improved machinery, to get a yield of at least 70 or even 75 per cent. Moreover, by the application of the principles of maceration to the residues, or marcs, this yield might be increased to about 90 per cent., and a residue left equal to no more than one-tenth of the original weight of the mass. Whereas, with all the large and clumsy apparatus at present used, and all the labour expended, a yield of more than 45 per cent, is rarely obtained. Many presses have been devised to take the place of the huge, old-fashioned cider-press. This unwieldy piece of mechanism often covers an area of 50 square yards, and requires the united strength of fifteen men to work it ; and yet, though many ingenious and labour-saving substitutes have been invented, this cumbrous monstrosity is still retained in many of the cider-producing districts of England and France. Of the improvements referred to, the best and most convenient is the hydraulic press ; unfortu- nately its price prevents its economical use by makers who produce only small quantities, but where the make is considerable it is to be preferred to any other. In small farms, an ordinary small screw press may be used with advantage. It is shown in Fig. 310. It will be seen that the principal screw turns two others, which are placed one on each side of the former ; by this means, the upper plate is subjected to a more uniform pressure, and better results are obtained than with a single screw. It furnishes a yield of 65 to 70 per cent, at the first pressing. The practice of submitting the crushed pulp to maceration, in order to extract the remainder of the juice, may be recommended without any hesitation. Two principal methods may be employed, according as it is desired to use the process simply as an auxiliary to the work of the screw press, or as a means for the extraction of the whole of the juice. In the first case, as much as possible of the juice is obtained by means of the press, the pulp being enclosed in bags ranged in rows, separated from each other by hurdles of wicker-work. The bags, when taken from the press, are placed in a tub, and subjected to the action of a sufficient quantity of tepid water for an hour. After this first maceration, they should be removed and placed in another tub with more water, wliile other bags are being put into the first tub. This is con- tinued until the pulp has been subjected four successive times to the action of water of decreasing CIDER. 419 density, when the contents of the first tub will have acquired the density of the natural juiee. The macerated pulp is afterwards pressed, the resulting liquid being used instead of pure water for the maceration of new supplies. In the second case, when the maceration is required to extract the whole of the juice, the apparatus is not quite so simple. It is shown in Fig. 311. The four vessels, A, B, C, and D, may be made of wood ; there may, with advantage, be six instead of four, in order to ensure the perfect maceration of the fruit. The cylinders E and F should be so constructed as to serve, should occasion require it, as receptacles, or as heating apparatus. When steam cannot be had, a coiled tube may be placed in each of these, through which may be passed the products of combustion from an ordinary stove. If the cylinder E contains liquid which it is required to raise into A, the register or regulator, which admits the heated gases into E, is opened ; the liquid thereby becomes heated, and the steam produced drives it up the tube into A. If, on the other hand, it be desired not to heat the contents to the boiling point, a small air-pump may be connected to M, by means of which the liquid can be driven up into A whenever the requisite temperature is reached. This latter method is preferable, since it is not advisable to heat the juice to a higher temperature than 70 (158 F.), in order to avoid the coagulation of albumen in the must. The fruit is, of course, prepared for the process by slicing with ordinary root-cutters. The liquid, when equal in density to the pure juice, is run directly into the fermenting vats ; the exhausted slices may either be pressed, or used at once as food for cattle. All the technical and mechanical questions concerning the advisability of macerating the fruit have been answered already by the success of the process in the extraction of sugar from the beet. There is now no reason why it should not be employed with equal success in the preparation of cider. Assuming that the juices of the apple have been extracted by either of these methods, and that all the precautions urged above have been carefully taken, the cider-maker has in his hands a must containing more or less saccharine matter, which requires only the process of fermentation to convert it into good cider. The same rules which regulate this operation in the case of wine, or any other alcoholic beverage, are applicable to this drink also ; and all those conditions which have been previously pointed out in the article on Alcohol as indispensable to its proper conduct must be scrupulously observed by the cider-maker desirous of success. And there are other conditions which he must not neglect in order to produce an article of good quality, containing a sufficient proportion of alcohol. One of these is to avoid too slow a fermentation, which invariably tends to produce lactic acid in place of alcohol, and in a very large proportion when the must contains much gum, dextrine, or viscous substances. If nitrogenous matter be present together with these, they will be decomposed, giving rise to myriads of fermentable germs, which cause the alteration and ultimate ruin of the product. A hurried fermentation is no less injurious: it produces the formation of acetic acid at the expense of alcohol, thus affording the harsh, disagree- able flavour which characterizes nearly the whole of the cider made at the present time. Above everything, care should be taken to see that the must contains water and sugar in correct propor- tions before submitting it to fermentation. The cider-maker, for the sake of increasing his yield, too frequently commits the serious blunder of diminishing an already inadequate proportion of sugar by additions of water to his must, thereby rendering it impossible to produce a drink of sufficient alcoholic strength. A must containing too little sugar infallibly gives rise to a bad fermentation. Acetic, lactic, and viscous fermentations ensue, in inverse proportion to the saccharine richness of the unfermented liquor. To avoid this, the maker must take every precaution to ensure a sufficient quantity of sugar therein, and he must not on any account whatever diminish it by the addition of water. By observing a simple rule, he may produce a cider equal in every respect to many wines, 420 BEVEEAGES. and capable of being preserved for any length of time. This rule is as follows : To see that the saccharine density of the must is as high as 10 5 Baume ; or, since other soluble matters are present besides sugar, which raise it as much as l-5 or 2, the total density of the must should stand at from 12 to 13 -5 Baume'. Besides having the proper relative proportions of water and sugar, the must should contain a sufficient quantity of astringent substances, and these, if not present, must be furnished to it. This is necessary to the success of the subsequent operation of clarifying the fermented liquor, which cannot be performed by artificial means without the assistance of these foreign matters. Catechu is the most convenient, on account of its comparative cheapness, and also because it imparts no taste to the drink. The quantity to be added varies, of course, with the natural astringence of the juices, but, as a general rule, a solution of 30 grm. per hectol. (about 20 grains per gallon) is sufficient. The process of active fermentation should be conducted at a temperature of not less than 15 (60 F.), and not higher than 25 (77 F.), in order to avoid either retarding or hastening the reaction. The process may be carried on in the open air, in vats of sufficient capacity, say 600 to 800 gallons. When the vat is filled to about five-sixths of its capacity, the sugar should be added, if this is necessary, either in the form of good fresh molasses, or of concentrated juice at a density of 28 to 30 Baume. The solution of catechu is next added, if the must is found to be wanting in astringence ; a good test is to add a little of a weak solution of gelatine, which, in that case, produces no precipitate, or a very faint one. The temperature of the must, and of the surrounding atmosphere, should then be carefully noted ; the latter should stand at 15 (60 F.) throughout the operation ; that of the must ought to be raised to 18 or 20 (64 or 68 F.), either by the addition of heated must or by steam. Great attention must be paid to these points of temperature. Although the juices contain minute quantities of a fermenting principle, it is always advisable, though by no means customary, to add a little good brewer's yeast ; 15 to 20 grains per gallon is quite sufficient. It should be mixed first with a little of the must, and then added to the contents of the vat with vigorous agitation. The vat may then be tightly closed, and the process suffered to proceed. In an hour, the contents of the vat are in a state of brisk fermentation, and carbonic acid gas is disengaged hi considerable quantities. It is never necessary either to remove the scum or to agitate the liquor in any way. The process is complete when the disengagement of gas ceases, and the liquor has fallen in density to 1 or 1'5, showing that all the sugar has undergone conversion into alcohol. It is then drawn off into tuns or barrels, where it undergoes another fermenting process. The usual length of the first or active fermentation is about sixty hours. The tuns into which the fermented liquor is drawn off hold usually 130 to 150 gallons ; they are completely filled, and the bung-hole at the top is simply covered with a piece of linen stretched across it. As soon as the fermentation recommences, the particles of suspended matter are carried to the surface and driven out at the bung-hole ; by this means the liquor becomes considerably purified. When this process is complete, which may not be for two or three months, the liquor is ready for clarification, which means the entire removal of all the causes of after-fermentation. The cider is first racked off into clean casks, which have been well sulphured, as already described. Here the process of clarification is performed. If the addition of catechu to the unfermented liquor have been made, the soluble albuminoid substances will be removed, by its means, on the further addition of a little gelatine or albumen ; more than enough to precipitate the catechu should not on any account be added. It is well to subject the cider to another clarification in a few weeks' time, especially if it is destined for sale. After this treatment, cider will keep as well as wine, and if sufficiently rich in alcohol, it will be much improved by bottling. The conditions of preservation are identical in the case of cider with those of the preservation of wine. When made from ripe fruit containing much sugar, and when there has been enough astringent matter in the must, and the two processes of fermentation have been properly conducted, and those of clarifying and racking have received due attention and care, there is no reason why cider should not be kept for an indefinite number of years, always provided that it be kept in a cool cellar, in good casks or bottles, and well out of contact with the atmosphere. In concluding this article it will be well to recapitulate briefly the most important points in the manufacture, and those to which the cider-maker should give his careful attention. 1. Many varieties of the fruit should be cultivated, in order that there may be a certain supply in all seasons; those -are especially to be desired which, when just ripe, contain the maximum quantities of sugar and tannin. 2. The apples must not be gathered before they have attained full maturity : they should fall to the ground when the tree is lightly shaken. 3. The gathered apples should be at once protected from rain or frost. If perfectly ripe, there is no necessity to lay them aside before using. 4. The division of the fruit is best performed by means of root-cutters if maceration alone is to be employed to extract the juice ; or by Berjot's mill if the press is to be used. 5. The extraction of the juice may be performed either by maceration or by pressure. COCOA. 421 6. When maceration alone is used, the must should be brought to the density of the natural juices ; in the case of pressure, maceration may be used to exhaust the squeezed pulp, but in such a way as not to increase the proportion of water, or to diminish the density of the must to less than that of the natural juices. 7. The extraction of the juice by pressure should be performed in a screw press, or hydraulic press if in great quantity, of simple construction, requiring but little power, and capable of producing at least 65 to 70 per cent, of juice. 8. The saccharine density of the must should be as high as 8 Baume for ordinary cider, and 12 to 13 "5 for cider destined for exportation. 9. A convenient quantity of catechu (20 grains per gallon) should be added to the must if the latter do not show a distinct precipitate when treated with a solution of gelatine. 10. These additions of sugar and catechu should be made to the must in the fermenting vat ; the latter should be rather deeper than wide in order to lessen the surface exposed to the air. 11. The temperature of the air in the fermenting room should be regulated at 14 or 15 ; that of the must should stand throughout the process at from 18 to 20 ; the process should be started by means of brewer's yeast (15 to 20 grains per gallon). The vats should be filled to about five- Bixths of their capacity, and should be covered up as soon as the process commences. 12. The liquor should be drawn off as soon as the process is complete after about sixty hours. The head or scum should be removed from the surface before drawing off. 13. The secondary fermentation should be conducted in clean tuns, of 130 to 150 gallons capacity, and quite full. 14. When the secondary fermentation is over, the liquor is racked off, during which process it is kept as much as possible from contact with the air, into casks properly sulphured and cleansed. 15. Clarification must be performed immediately after the first racking off. A test of the liquor with gelatine should be made before adding more catechu. 16. Another racking should follow immediately after the clarification. A second clarification and racking off should be performed upon cider for exportation. When made, the cider should be placed in casks of 50 to 60 gallons capacity, similar to those used for wine. These should be stored in cool cellars. 17. When sweet cider is desired, the first process of fermentation may be checked as soon as the cider has attained the proper degree of sweetness. Secondary fermentation should be hindered by frequent repetitions of the clarifying and racking-off processes, and by well sulphuring the casks. Careful attention to all these points cannot fail to result in the production of an exceedingly agreeable and perfectly wholesome beverage, which is certainly more than can be said of the cider of to-day. The process which has been described is in actual operation in Normandy, and it yields results which are little short of perfection. There is nothing to prevent similar results from being attained in this country, and the preparation of really good cider would be a source of much benefit to the community at large, since it might to a large extent take the place of beer, a beverage which is extensively adulterated, and hence often very injurious to its habitual consumers. Cider is, or might be, also much more cheaply produced than beer. The cultivation of apples upon land highly favourable to their growth, but now lying utterly waste, such as railway cuttings and embankments, would in a few years greatly increase the production of fruit, and tend to lower the cost of the manufactured beverage. Vast numbers of acres of such land, upon which thousands of tons of apples might be grown, with profit to the cultivators and benefit to the community, now, for want of a little enterprise on the part of the railway companies, produce nothing but rank herbage of little use as fodder, and consequently of no commercial value. The cost of covering this land with apple and pear trees would be very small ; and, apart from the value of the fruit itself, the presence of the trees would probably be of great service as a means of preventing the soil from slipping. This mode of utilizing the slopes of railways has already been partially adopted in some countries of the Continent. PERRY. (FR., Poire; GER., Birnwein.y Perry is another wholesome beverage, resembling cider, and made from pears in the same manner that cider is made from apples. The harsher sorts, or those that are too tart for eating purposes, make the best perry. The manufacture of this drink is exactly similar to that of cider ; and the remarks made concern- ing the latter apply, in every particular, to perry. As shown in the table on p. 414, pears contain a little more sugar than apples, and consequently yield a slightly larger proportion of alcohol. Cocoa. (FR., Cacao ; GER., Cacao.) Cocoa, a preparation of the roasted seeds of the Theobroma Cacao, is very widely consumed in various forms. It is wholesome, pleasant flavoured, and highly nutritious ; and the quantities in which it is prepared and sold for use as a beverage proclaim it to be an article of commerce second in importance only to tea and coffee. As common beverages, these three have a strong claim to consideration, not only on account of their universal consumption in this country, but also ecause, familiar as people are with them, few 422 BEVEEAGES. really know how to prepare them iu the most wholesome and agreeable form, and much of their flavour and tonic properties is frequently wasted by an incorrect mode of preparation. The active principle in cocoa is theobromine, an alkaloid closely resembling those contained in tea and coffee, but of less powerful effects. It also contains 50 per cent, of a peculiar fatty or oily substance, called butter of cacao ; and 20 per cent, of albumen, from which it obtains its nutritive properties. The cocoa of the shops is always mixed with a small proportion of arrowroot, or some other starch, in order to render it soluble, or rather emulsive. Being very nourishing and at the same time very easily digestible, cocoa, when well prepared, strengthens the digestive organs and quickly raises the tone of an exhausted or enfeebled system. Hence it is the favourite beverage of invalids and dyspeptic persons. Its exhilarating effects are nearly equal to those of tea and coffee. Upon some persons, however, it acts, for reasons which are not well known, as a mild emetic. Cocoa appears in the market in three forms, besides that of chocolat : cocoa nibs, flake cocoa, and soluble cocoa. Cocoa nibs are the roasted seeds from which the skins and hu.;ks have been removed in a " kibbling-mill." They should be of a dull, greyish-red colour ; but they are often coloured with Venetian red. Flake cocoa is the purest of the other two varieties, since it contains no sugar and only a small quantity of starch ; it is prepared simply by grinding the roasted " nibs " in a mill constructed of two metallic cones working one inside the other. Soluble cocoa is the form in which the substance is generally used ; it consists of the roasted nibs ground up with varying proportions of starch and sugar, for the purpose of rendering the cocoa readily diffusible in water. Sago and arrowroot are the most wholesome ingredients, but much adulterated and highly coloured starch of an inferior description is employed by second-rate makers. Chocolat is cocoa made into a paste with sugar and certain flavouring ingredients, usually vanilla. It is pleasant and nutritive, but sometimes disagrees with weak stomachs. Good, unadulterated chocolat may be known by the following characteristics : It is compact, brittle, and of a reddish-brown colour. It should break only with a moderate effort, and the fracture should be clean, and the gra'in fine. When worked into a paste, it should be perfectly homogeneous. It should melt easily in the mouth and possess a pleasant, fresh flavour. It should dissolve readily in milk or water, leaving no residue. Chocolat is made by crushing cocoa nibs in a mill, the rollers of which are made either of stone or metal, and heated by steam in the interior. By this means, the fat or butter is melted, and the cocoa is softened into a thick, smooth paste. To this paste is then added the required amount of sugar and vanilla or other flavouring matter, and the whole is well mixed together in a mixing mill until the mass becomes perfectly homogeneous, when it is moulded into various shapes. Chocolat is made as a beverage by reducing the necessary quantity to a fine powder and placing it in a jug, or other receptacle, with a little boiling water. The whole is then well mixed and stirred up with a spoon into a thin paste, and the jug is filled up with boiling milk and water. Sugar may either be mixed in with the paste or added afterwards in proper quantity. The drink ought never to be prepared before it is required for the table, since, on reheating, it not only loses flavour, but the oil or butter separates and collects on the surface, which is generally the cause of the ill effects produced by chocolat on weak stomachs. Cocoa is usually prepared for the table by simply pouring boiling water upon the soluble powder. If the flaked variety or nibs be used, they must be placed in boiling water and simmered gently for from four to six hours. Great care must be taken to see that the liquid does not boil, in order that the albumen may not be coagulated, and the cocoa thus prevented from thoroughly mixing with the water. Cocoa beverage is an emulsion ; that is to say, it is a liquid which contains solid matter in suspension, and hence may be considered as food and drink combined. While the liquid portion of the beverage bus almost as exhilarating an effect upon the system as tea and coffee, the solid portion, consisting of carbonaceous and nitrogenous matter, is highly nutritive. Coffee. (FR., Cafe; GER., Kaffee.) Coffee is a decoction or infusion prepared from the roasted berries of the Coffea Arabica, a plant largely cultivated in Arabia Felix and in various other parts of the globe. Some notion of the importance of coffee as a beverage may be gained from the fact that forty millions of pounds are consumed annually in the United Kingdom, and it is said that the annual consumption of the entire world amounts to the enormous quantity of six hundred million pounds. The chief constituent of coffee, to which it owes its peculiar effects, is caffeine, a powerful alkaloid identical with theine and closely resembling theobromine. It also contains tannic acid and small quantities of a bitter aromatic oil. The action of these constituents is stimulating, tonic, and ex- hilarating, without producing any unpleasant after-effects. They promote digestion, raise the spirits, and are strongly anti-soporific. Coffee berries undergo important changes during the process of roasting. It is carried on until they have changed to a chestnut-brown colour and lost 18 per cent, in weight, but it should not be stopped before, or carried farther than, this point. COFFEE. 423 The object of the process is to develop the aroma of the coffee and to render the berries less tough, in order that they may be easily ground in a mill. Too much heat removes the peculiar principles which it is desired to retain, converting them into others of disagreeable flavour and odour ; too little heat, on the other hand, produces raw, green, and flavourless berries, the infusions of which are unpalatable and liable to cause vomiting. Coffee is rarely made in a proper way in England. The chief characteristics of English-made coffee are weakness and lack of flavour, owing to the fact that it is invariably made as a decoction instead of an infusion ; that is to say, instead of allowing the powder to digest, simply, in hot water, it is almost always boiled, often for a considerable length of time. It must not be supposed, however, that the boiling is in itself objectionable ; that this is not the case is sufficiently proved by the fact that the very best coffee is made by making a decoction of one half of the powder, and an infusion of the other half, and then mixing the two liquids ; but if the whole of the coffee is boiled in the pot, it loses its delicate flavour, becoming rank, and quite unpalatable. The French proceed far more intelligently in their methods of making this infusion, and the superiority of the French coffee over that made in England is everywhere acknowledged. The object is, by treating the powdered coffee with boiling water, to extract the whole of the soluble constituents of the berry, or those in which its peculiar flavour or aroma are contained. In the first place, the French take much larger quantities of the coffee than is customary in England ; the proportions used being about one ounce of the powder to each breakfast-cupful of water ; if the coffee be required very strong, this proportion may be doubled ; the addition of a teaspoonful of freshly ground and roasted chicory is thought by some to improve the flavour of the beverage. The coffee is generally both freshly roasted and ground. When the berries have been well roasted, the product, after treatment with boiling water for a few minutes, should contain the whole of the flavouring, and a few other soluble constituents. It is the custom in France to improve the quality of the drink by pouring a little boiling water upon the exhausted " grounds," allowing it to macerate until cold, then boiling the separate liquid and using it for making infusions of fresh coffee. In cafe's, the grounds made during the day are afterwards mixed together in a pot, and boiled with water ; the decoction thus made is added in small quantities to the infusions of fresh coffee and it much improves their quality. In order to remove the suspended grains and to render the coffee perfectly clear, a little isinglass or white of egg may be added to it ; these, however, diminish the astringency and vivacity of the coffee. In France, it is customary to effect this by pouring a little cold water upon the surface of the hot coffee in the pot ; the cold water being heavier than the hot liquid underneath it, sinks at once, carrying with it all the suspended matter. In Arabia, a cold, wet cloth is often wrapped round the pot for the same purpose. The best and most convenient form of coffee-pot is called a " percolator," and is the invention of a Frenchman named De Belloy. It consists of two metal vessels, placed one above the other, the upper one being made to fit into the lower one. The bottom of the upper vessel is perforated with numerous very small holes. The powdered coffee is placed in this, and boiling water poured over it, the lower vessel receiving the beverage ready-made. After removing the upper vessel, a little of the decoction made, as already described, is added, and the coffee is clarified as above, when it is ready for the table. The addition of milk to coffee is said to destroy much of its tonic properties. Ginger-beer. (FK., Biere de gingembre; GEB., Ingwerbier.) Ginger-beer is a cooling and refreshing beverage containing an infusion of ginger, and is strongly effervescent. Being very wholesome and cheap, it has become a favourite summer drink among the lower classes of society. It is often recommended as a restorative after fatigue. Below are given several good recipes for its preparation on a large or a small scale. 1. Best lump-sugar, 1 Ib. ; Jamaica ginger, unbleached and well bruised, 1 oz. ; two or three sliced lemons ; cream of tartar, f oz. ; boiling water, 1 gallon. Macerate until nearly cold in a covered tub or clean vessel, with constant stirring; add 1 or 2 oz. of yeast, and place the vessel in a warm place to ferment. Allow to stand until the next day ; then decant the clear liquor and strain it through a piece of flannel ; allow to ferment again for a day or two, according to the weather. It may then be skimmed, strained, bottled, and securely wired down. 2. White sugar, 18 to 24 Ib. : Jamaica ginger, If Ib. ; Narbonne honey, 1 or 2 Ib. ; lemon or lime juice, 1 quart ; pure soft water (which has been boiled and allowed to settle), 18 gallons. Boil the ginger in 3 gallons of the water for half an hour ; add the sugar, lemon juice, honey, and the remainder of the water, and strain the mixture as above. When nearly cold, add the white of one egg and oz. of essence of lemon ; stir well for half an hour. Allow to stand from three to six days, according to the weather, and bottle it, placing the bottles on their sides in a cool cellar. The ginger-beer is ready for use in about three weeks, and will keep several months. 3. Best white sugar, 8 Ib. ; Bar Dadoes ginger root, 12 oz. ; gum-arabic, 8 oz. ; tartaric acid or cream of tartar, 3 oz. ; essence of lemons, 2 drachms; water, I) gallon d. Boil the ginger root for 424 BEVEEAGES. half an hour ; strain the liquor ; add the tartaric acid and sugar ; boil well, removing the scum ; add the gum-arabic, dissolved in a separate portion of the water, and the essence of lemons : allow to cool to about 38 (100 F.) ; add a little fresh yeast, and carefully ferment as above. The liquor may then be bottled for use. Lemonade. (Fu., Limonade; GER., Limonade.) The manufacture of effervescing lemonade on a large scale has been fully treated of under Aerated Waters. But it is often required to produce this beverage on a small scale, for domestic use. Its agreeable flavour and very refreshing effects render it a favourite drink in hot weather, especially for children. And, in cases of fever, it is of great use as a refrigerant and antiseptic. The following recipes for its preparation are therefore given : 1. Sliced lemons, two in number ; sugar, 2 oz. ; boiliug water, 1 pint. Mix well ; cover the vessel and allow it to stand until cold, stirring it occasionally. Pour off the clear liquid, and strain through a muslin or hair sieve. 2. Juice of three lemons ; peel of one lemon ; sugar, 1 J Ib. ; cold water, 1 quart. Digest for five or six hours, or all night ; then strain as above. 3. Citric acid, 1 to 1 drachm ; essence of lemon, 10 drops ; sugar, 2 oz. ; cold water, 1 pint. Mix well together and stir until dissolved. Made as above, lemonade is a very refreshing and wholesome beverage. Instead of the citric acid in the last recipe, tartaric acid is sometimes used. Lemonade for icing should contain a larger proportion of sugar than is indicated in the above recipes. The refreshing effects of lemonade are greatly increased by aeration. Aerated lemonade may be made, in small quantities, without the aid of machinery, in the following ways : 1. Place in the bottles 1 to 1 oz. of lemon syrup ; essence of lemon, 3 drops ; bicarbonate of soda, J drachm. Then nearly till the bottles with water, having the corks ready prepared, and add to each bottle 1 drachm of crystallized tartaric acid, instantly corking and wiring it. The bottles should be kept inverted in a cool place, or preferably in a vessel of ice-cold water. In this recipe, instead of lemon syrup, f oz. of lump-sugar may be used. 2. Lump-sugar, 1 oz. ; essence of lemon, 3 drops ; bicarbonate of potash, 25 grains. Fill th bottles with water and proceed as before, adding of crystallized citric acid, 45 grains. This recip* gives a more wholesome beverage, especially for the scorbutic, dyspeptic, rheumatic, and gouty. The following are recipes for lemonade powders : 1. For one glass. Powdered citric or tartaric acid, 12 grains; powdered white sugar, \ oz. essence of lemon, 1 drop, or a little of the peel rubbed off on to a lump of sugar. Mix the whole well together. 2. White sugar, 4 Ib. ; tartaric or citric acid, \\ oz. ; essence of lemon, \ oz. Mix well and keep in a bottle for use when required. One to two dessert-spoonfuls make one glass of lemonade. 3. Effervescing. For the blue papers, powdered white sugar, 1 Ib. ; bicarbonate of soda, J Ib. ; essence of lemon, l drachm. Mix well and put up in six dozen papers. Then put up 5 oz. of citric or tartaric acid in six dozen white papers. Or the two powders may be kept in separate bottles. On the Continent, mineral lemonade is the name given to various beverages, consisting of water to which a little mineral acid has been added, and sweetened with sugar. Thus they have limonade sulphurique, chlorhydrique, nitrique, phosphorique, &c. ; these are used as cooling drinks in cases of fever, inflammation, skin diseases, &c. Spruce-beer. (Fn., Sapinette ; GER., Sprossenbier.) Spruce-beer is a cooling and refreshing beverage, made from essence of spruce and molasses or sugar. There are two kinds made, the brown and the white, the latter being generally used and preferable to the other. It may be prepared by dissolving 7 Ib. of loaf sugar in 4i gallons of hot water. When the heat has fallen to about 32 (90 F.), 4 oz. of essence of spruce is mixed in and dissolved perfectly by agitation. Half a pint of good brewer's yeast is then added and mixed thoroughly. In summer, fermentation speedily sets in; but in winter, it should be excited by keeping the cask in a warm place. When the fermentation slackens, the liquor is drawn off, the cask well washed, and the liquor returned to it A new fermentation soon commences, and, when complete, the liquor may be bottled. The bottles should be wired ; and in order that the liquor may mature quickly, it is advisable to place them on their sides until it has become brisk then they should be set on end to prevent them from bursting. Brown spruce is made in the same way, brown sugar or molasses being substituted for loaf sugar. Another good recipe for spruce-beer is the following : Essence of spruce, i pint ; pimento and ginger (bruised), of each, 5 oz. ; hops, ^ Ib. ; water, 3 gallons ; boil the whole for ten minutes, then add of moist sugar, 12 Ib. ; warm water, 11 gallons ; mix well, and when lukewarm, add of yeast, 1 pint. After the liquor has fermented for about twenty-four hours, it may be bottled. TEA. 425 Spruce-beer is diuretic and anti-scorbutic ; it is an agreeable drink in summer, and is considered particularly useful during long sea-voyages. Tea. (FR., The ; GEB., Thee.) Tea is an infusion of the dried leaves of the Chinese tea-plants Thea Bohea, Thea viridis, and others. Of all the beverages of this class, tea is by far the most extensively drunk in this country ; upwards of 140 millions of pounds are annually consumed in the United Kingdom ; the total import of tea in 1876 nearly reached the enormous quantity of 186 millions of pounds. On the Continent, however, the consumption is very small as compared with that of coffee. The principal constituent in tea is tannin. Besides this, it is found to contain a volatile oil, to which its aroma is due, resin, gum, extractive matters, nitrogenous substances analogous to albumen, various salts, and an alkaloid called theine, which is identical with the caffeine of coffee ; the proportion of nitrogen in the dried leaves is from 5 to 6 per cent. Of the total constituents, the amount soluble in boiling water varies from 38 to 47 per cent., and depends chiefly upon the age of the leaf. The action of tea upon the system is stimulating and invigorating. It is an agreeable antacid, and is exceedingly refreshing if drunk when fatigued or after exercise. The proper time to drink tea, and when its effects are most beneficial, is about three hours after dinner. At this time, the digestion of the meal is just complete, and there remains in the stomach an excess of gastric juice which creates an uneasy sensation unless it is neutralized by a mild antacid such as tea or coffee. For this purpose, the simple infusion, containing no milk or cream, or very little, and no sugar, is best adapted. The presence of the alkaloid theine in tea has the remarkable effect of sensibly retarding the waste of the animal body, and thus of diminishing the necessity for food to repair it in an equal pro- portion. In other words, by the consumption of a certain quantity of tea, the health and strength of the body will be maintained in an equal degree upon a smaller supply of ordinary food. Tea therefore stands to a certain extent in the place of food, while at the same time it refreshes the body and stimulates the mind. Tannin probably aids also in the exhilarating effects produced by tea ; it imparts to the infusion an astringent taste and a somewhat constipating effect upon the bowels. The practice of "facing" tea, as it is termed, cannot be too strongly condemned. Formerly, large quantities of Prussian blue were used in China to impart a fictitious colour to green teas ; about 1 oz. being used to 14 Ib. of tea. More recently it is said that indigo has been substi- tuted, in consequence probably of the injurious effects which European writers have described the Prussian blue as possibly producing on the constitution of green-tea drinkers. Less doubt exists as to the pernicious qualities of an adulterated tea largely manufactured by the Chinese, under the name of Lie tea. This consists of the sweepings and dust of the tea-warehouses, cemented together with rice-water and rolled into grains. These adulterated teas have been imported into this country to the extent of half a million pounds weight in a single year. In this, as in other similar cases, the poorest classes, who can least afford it, are the greatest sufferers from the fraudulent introduction of the spurious mixture into the teas they buy. Black teas are some- tunes faced with finely powdered plumbago or blacklead. The common way of making the infusion is well known to everyone. The tea is placed in a tea- pot, is previously heated with hot water, and covered with boiling water. This is allowed to infuse for some minutes, and the teapot is then filled up with boiling water as required. If the water be boiling when poured upon the tea, as it always should be, about ten or fifteen minutes suffice to extract the whole, or nearly the whole, of the soluble constituents. Toddy. (FR., Toddi. ; GER., Toddy.) Toddy is the sweet juice obtained from various trees of the palm species. When the trees ar required to yield toddy in place of fruit, the flower-stalks are, when just efflorescent, cut off, and a deep incision is made in the stump, from which, after repeated beatings, the toddy flows into vessels hung beneath to receive it. One tree, when full-grown, will sometimes yield as much as six pints of toddy per diem. Toddy, when quite fresh, is a cool, delicious, and wholesome beverage ; after standing a few hours, it ferments and becomes highly intoxicating. It serves extensively as yeast, and throughout Ceylon, no other is employed by the bakers. A kind of vinegar is also prepared from it which is used for pickling gherkins, limes, the undeveloped leaves of the cocoa-nut and the palmyra trees, and various other vegetable substances. By far the larger quantity of toddy made is used in the manufacture of "jaggery," a species of sugar, resembling maple sugar, of which it is said that upwards of 1000 tons are annually made in Ceylon. According to Forbes, three quarts of toddy will produce 1 Ib. of jaggery. In Jaffna, the unfermented juice is boiled to the consistence of a thick syrup ; this is poured into baskets made of plaited palm-leaves, when, on cooling, it crystallizes into jaggery. In these baskets, the jaggery ia kept for home consumption, or exported to other 426 BEVERAGES. lands to be refined. Jaggery forms an article of commerce from the upper to the lower pro- vinces of Burinah, and is also of importance in some of the islands of the Indian Archipelago. Besides being exported in large quantities from Ceylon, it forms a considerable portion of the food, of the Tamil population of Jaffna. Amongst a variety of purposes to which it is put is that of being mixed with the white of eggs, and with lime from burnt coral, or shells. The result is a tenacious cement, capable of receiving so beautiful a polish that it can only with difficulty be distinguished from the finest white marble. Water. (F R ., Eau ; GEB., Wasser.) In an article on Beverages, water claims to occupy a prominent position, both on account of its own importance as a common drink, and by reason of its forming the basis of numerous others. Besides, though water for drinking purposes is not manufactured or prepared, it is nevertheless an article of commerce, since it must be purchased by its consumers from the water companies which collect and supply it, and paid for in much the same way as any other article of food or of daily consumption. For this reason, also, it could not properly be omitted from the list of commercial beverages. The primary source of water is the sea ; but all fresh water reaches us through the medium of the clouds, which are water in a state of vapour suspended in the atmosphere. A gigantic process of distillation is continually going on, owing to the evaporation of the water of seas, rivers, lakes, &c., by the heat of the sun. The vapour of water thus formed is recondensed by contact with a colder atmosphere above, and falls back to the earth in the form of rain, snow, and hail. In this way, the earth is furnished with a constant supply of water distilled from the ocean by the agency of the sun and the natural heat of the earth. As it falls through the atmosphere, rain absorbs a considerable quantity of the free gases existing in it, and hence becomes aerated with oxygen, nitrogen, and carbonic acid in varying proportions. Eain water is a powerful solvent, and therefore always contains more or less matter in solution, together with small quantities of dust which float about in dry air and are washed down by the first portions of the rain. Besides the free gases of which the atmosphere is composed, there are many gaseous impurities present, of which traces are invariably found in rain water ; these, however, are generally in such minute quantities that, if free from suspended matter, rain water may be practically considered as pure. If it is caught in basins or tanks, and stored for any length of time, especially with exposure to the air, it soon becomes foul and impure by the introduction of foreign matter containing seeds or germs, too minute to be visible, but capable, under the influence of light and heat, of loading the water with myriads of living organisms, which die and become putrid. In this state, water is wholly unfit for drinking purposes, and it must be carefully filtered before using. Eaiu water, owing to the absence of saline matters, is more favourable to the production and development of these organisms than water obtained from rivers, brooks, and springs, and should therefore never be used after long exposure to the air. Soft water, containing carbonic acid gas, exerts a solvent action upon lead ; hence tanks and pipes of these metals should never be employed. The insipid character of rain water and its liability to develop organic life render it unsuitable for general use as a beverage. The water in lakes and ponds which are not supplied by running streams is rain water caught and retained in natural depressions of the earth, or in valleys closed at the lower end by some obstacle. Here it comes into contact with the soil and with vegetable matter, and becomes charged with organic impurities; these, however, are not injurious to health unless they are permitted to become putrid. The vegetable life so abundant in most lakes and ponds of large size gives oft much carbonic acid gas, which is retained in solution in the water, and this gas renders it much brisker and fresher to the taste than ordinary rain water. That the water of ponds is better fitted than any other for drinking purposes is clearly shown by the fact that the instinct of cattle leads them to prefer it to running water, or to rain water caught in tubs, and that they are more healthy when they have access to the former kind. Rain water which falls in hilly districts and on the sides of mountains collects in streams and brooks, of greater or less size ; these gradually unite, forming rivers. In such waters, the impurities are often visible to the eye. It is frequently of a red colour as it flows through rocks of red marl, which contain much oxide of iron in their composition ; it becomes milky in colour as it descends from the glaciers of Iceland or the slopes of the Andes, owing to the fine white sand which it takes up in its course. Many of our English rivers are grey or brown in colour; they are brown when running through a peaty or boggy country ; and when the quantity of suspended vegetable matter is excessive, they are sometimes quite black to the eye. Only when perfectly clear, is the blue colour natural to large masses of water distinctly perceptible. But among the rocky and other materials with which water comes in contact in and upon the earth, there are many which it can dissolve, and the presence of which cannot be detected by the sense of sight. Hence, the clearest and brightest of waters those of springs and transparent rivers are never chemically pure, even when filtered; they all contain in solution a greater or less quantity of saline matter, sometimes so much as to give them a decided taste, and to form what are called mineral waters. The following WATER. 427 table shows the amount in grains per gallon of solid mineral matter contained in the waters of some important lakes and rivers: Boston (U.S.) water-works .. ! 22 grains. Charles River, Massachusetts 1 '67 Bala Lake 1'95 Loch Katrine 1-96 Thirlmere 3'60 Schuylkill River, Philadelphia 4 -26 Detroit River, Michigan Ohio, at Cincinnati Spree, at Berlin .. .. Loire, at Orleans .. Danube, near Vienna . . Lake of Geneva . 5 '72 grains. 6-74 7-98 9-38 9-87 10-64 , Lime in combination with carbonic and sulphuric acid is the most common impurity in stream and river water ; and it is to this substance and to magnesia that such water owes the property termed " hardness," or that of curdling with soap. Pure waters are always soft ; and from this quality the absence may be inferred of any large proportion of lime and magnesia salts. Waters containing much lime are often bright and sparkling to the eye and agreeably sweet to the taste. They become somewhat milky when boiled, and leave a sediment which encrusts the inside of kettles or boilers. When strongly impregnated with lime, they will even deposit a calcareous coating along their channels as they flow in the open air, or will petrify, as it is termed, any substances immersed in them. These circumstances are due to the fact that the lime is held in solution in the water by the help of free, dissolved carbonic acid gas, and when this gas is permitted to escape, or driven off by boiling, the lime can no longer be retained in solution, and it is accordingly deposited. Hard waters, therefore, are generally made much softer and purer by boiling. If, however, much lime be present in the state of sulphate, mere boiling will not softeu it, but if a little soda be added during the boiling, the sulphate will be decomposed and readily separated. A good and cheap method of softening hard waters is now being carried out by several of the largest English water companies. It is known as " Clark's process," and consists in adding lime water to the water already containing lime. The lime added combines with the excess of carbonic acid gas, which holds in solution the lime present in the water, and the latter portion, and also the newly formed carbonate, are precipitated to the bottom of the tank or reservoir. It will thus be seen that the water which collects in hilly districts and flows in streams and rivers through all kinds of country and over many different rocks and soils may, and generally does, contain organic and saline matters both in solution and in suspension. It is not, therefore, to be recommended for drinking purposes until it has been softened and filtered. Spring and well water is that which falls upon and filters through porous rocks. Owing to the carbonic acid which it contains, it dissolves a large quantity of saline matter as it filters through the different strata. In its downward course, this water sooner or later reaches a stratum which it cannot permeate, and is hence brought to a stand. If, however, the stratum happen to lie on an inclined plane, the water runs along it, and eventually issues from the earth where the rock crops out. It is in this manner that all springs and wells are formed, the latter being constructed by digging through several strata until one is reached upon which water is standing or over which water is flowing. As we have already seen, the solvent properties of water enable it to take up many substances from the rocks and soils through which it passes, and it often happens that in the neighbourhood of dwellings and farmyards, and especially in towns, the water of shallow wells becomes very impure, and consequently unwholesome to drink. The rains that fall upon the filth accumulated in towns wash out the soluble substances it contains, carry them into the soil, and through this, by degrees, to the wells by which the wants of the inhabitants are supplied. This has often been productive of serious and fatal disease. Hence arises the necessity of preventing, as far as possible, the accumulation of refuse, and, when such accumulation is unavoidable, of placing it at the greatest possible distance from wells which yield water for daily use. And hence, also, the advisability of bringing water from a distance for the supply of large towns. The proximity of graveyards to wells and springs from which drinking water is obtained is still more liable to render the water unwholesome by charging it with all kinds of objectionable matter. Water from a well standing close to an old churchyard in the neighbourhood of London, and analyzed by Noad, was found to contain the enormous quantity of 100 grains of solid matter per gallon, more than half of this consisting of nitrates of lime and magnesia. The presence of these salts in such quantity could only be traced to the proximity of the graveyard, as they are invariably produced by the decay of animal matters in porous soils. Well water frequently contains vegetable matter also, and of a kind which renders it wholly unfit for drinking purposes. In sandy districts, the decaying vegetable matters of the surface soil are observed to sink down and form a thin yellow layer in the subsoil, which is impervious to water. Being arrested by this layer, the rain water, while resting upon it, takes up a certain quantity of the vegetable matter ; and when collected in wells, it is often dark-coloured, marshy in taste and smell, and very 428 BEVERAGES. unwholesome. Purification of such water may be effected by filtering it through charcoal, or by putting chips of oak wood into it. Or it may be boiled, thus causing the organic matter to coagulate, as it were, and to collect in flocks, when the water cools, leaving it wholesome and nearly free from taste and smell. This property of being coagulated by boiling, and by the tannin contained in oak wood, show that the organic matter in water is of an albuminous character, or resembles white of egg. By coagulating, the organic substances not only fall themselves, but carry down other matter, thus completely clarifying or purifying the water. The sources from which country villages are supplied with drinking water are almost always shallow wells, each house or cottage having its own. As a rule, no care is taken to prevent the water in these wells from being contaminated with foul organic refuse, and hence it is rarely fit for drinking purposes. In some cases, manure heaps, pigstyes, and even cesspools, are permitted to remain in close proximity to the well which supplies whole families with water for drinking, cooking, and other purposes. Water from such wells is not only unfitted for consumption, but, from a sanitary point of view, absolutely dangerous. If it be impossible to avoid the contamination of the water in these wells, the best and safest plan to adopt in villages would be to establish one large deep well for the supply of the whole, placed in such a position as to be readily accessible and yet far removed from all chance of pollution with sewage and other injurious foreign matter. In the larger villages and towns, the supply is obtained either from such deep wells or from a neighbouring stream or lake, the water being purified sometimes by filtration through a bed of sand or gravel, and then conducted by means of underground pipes to the different streets and houses. Water thus supplied is, of course, much more wholesome than that obtained from shallow wells, but it is well never to use it for drinking purposes without careful filtration through a carbon filter, in order that any accidental impurity taken up in the underground pipes may be removed. Many means have been adopted of removing impurities from natural water, in order to render it potable. Muddy water is easily rendered clear and bright by processes of filtration on a large scale. In places where the only available water is muddy, the purification is effected in what are termed " filtering tanks." These consist of large, water-tight basins, on the bottom of which is placed a layer of small stones ; above these is placed a second layer of coarse sand or gravel ; over this again a layer of fine sand, and at the top a layer of river sand. The muddy water is introduced from above and filters through the several layers, collecting in the bottom one. From thence it passes into reservoirs, or shafts built vertically in the basin, and having their walls so perforated at the lower extremity that nothing but filtered water can pass through them; this water is pumped up from the shafts when required. Iron tubes perforated below are sometimes used instead of the brickwork reservoirs. The greater portion of the suspended impurities con- tained in the water is retained in the uppermost layer of sand, which has, consequently, to be renewed from time to time. In order to remove decaying organic matters or impure gases held in solution, powdered charcoal is frequently used as the filtering medium. In this way, not only are all suspended matters elimi- nated, but water which is coloured brown and possesses an offensive taste and smell, from the presence of the above matters, may be rendered clear, tasteless, and inodorous. The cost of the charcoal, however, which soon becomes impure and useless, prevents its application to this purpose on a large scale. And it is possible that charcoal which has become saturated with organic impuri- ties at a low temperature may give up a portion of the absorbed substance when the water to be filtered has a higher temperature. Carbon filters are frequently used on a small scale with great advantage for the filtration of impure waters. (See Filtration.) Drinking water should be clear and colourless, that is, absolutely free from suspended im- purities, such as clay, organic matter, &c. It should contain small quantities of dissolved carbonate of lime, chloride of sodium, oxygen, and carbonic acid gases. It should not contain any salts of lime and magnesia, except the carbonates, nor the smallest trace of any nitrates from which the presence of ammonia or nitrogenous organic matter may be inferred. When drinking water is boiled to dryness, it should leave a residue of from 10 to 30 grains of solid matter for every 100,000 grains of water, and of this quantity about one-half should be carbonate of lime. Water containing less than 10 parts of solid constituents in every 100,000 is soft and insipid, and less fitted for drinking purposes than that which contains a higher proportion. Of the free gases held in solution by the water, it should always contain 0'8 per cent, by volume of oxygen, 0'7 per cent, of nitrogen, and a considerable quantity of free carbonic acid. Suspended and organic impurities should invariably be removed, if present, by passing the water through a carbon filter. Indeed, no water should ever be used for drinking purposes, especially in large towns, which has not been subjected to careful filtration. Water that is to be used for brewing ales and porter should contain a considerable quantity of saline constituents, and principally of carbonate and sulphate of lime ; that used in brewing the best Burton ales contains from 10 to 20 grains per gallon of each. Common salt is also a valuable constituent. There should be no organic matter. Analyses of some of the best waters for WATER. 429 brewing will be found in the article on Beer. For wine-making, the water employed should contain a smaller proportion of mineral constituents than that required for beer. The very best would be rain water, to which the necessary proportion of the various salts has been added. This, however, would be impossible in practice, and it is found most convenient to use river or stream water, the composition of which is known and may be constantly relied on. The water of springs, or of stagnant ponds and marshes, which might contain putrid organic matter, either in suspension or solution, must not on any account be employed. The same conditions apply to water which is to be used in preparing whisky, or other spirit ; it should contain a small proportion of mineral salts ; it should be free from organic matters ; and it should always be clear and bright. For making infusions of tea and coffee, the most suitable is a soft water, or one containing no salts of lime, or very little. Rain water, carefully filtered, is the best for this purpose. Below are given some typical analyses of waters obtained from the different sources described, namely, lakes, rivers, and deep wells : Thirlmere Lake (in 100,000 parts). Total solid impurity Organic carbon . . Organic nitrogen . . 2-66 0-194 0-004 0-003 N itrogen (as nitrates and nitrites) 002 Total combined nitrogen .. .. 0-008 Chlorine 0-52 Total hardness . 0'70 The Thames, at Twickenham. Total solid contents . Carbonate of lime . . magnesia Sulphate of lime .. . soda .. 32-01 18-23 1-47 0-64 2-86 Sulphate of potash Chloride of lime .. Silica Organic matters . . 0-95 2-50 0-39 4-97 The Seine, above Paris. Total solid contents .. .. .. 17-90 9-20 Sulphates of soda and magnesia Chloride of lime Silica, alumina, and iron .. t Strassburg. Chloride of soda Nitrate of potash Silica . 1-00 1-00 0-80 0-20 0-38 4-88 0-25 0-58 0-74 0-17 0-85 2-38 0-39 magnesia Sulphate of lime .. Total solid contents .. .. .. 3-90 .. .. 2-00 The Rhine, a .. .. 23-18 13-56 magnesia Sulphate of lime .. .. soda .. .. Total solid contents .. Carbonate of lime magnesia Sulphate of lime magnesia .. .. 0-51 .. .. 1-47 .. .. 1-35 The Ehone .. .. 18-20 .. .. 7-89 .. .. 0-49 .. .. 4-66 .. .. 0-63 Alumina Iron at Geneva. Sulphate of soda Chloride of soda Nitrate of soda Silica Alumina The Danube, at Vienna. Total solid contents Carbonate of lime Sulphate of lime .. Total solid contents Carbonate of lime Sulphate of soda 12-62 8-37 1-50 0-29 Sulphate of magnesia .. Sulphates of soda and potash Silica Iron The Spree, at Berlin. 11-40 6-50 0-90 0-60 Sulphate of potash Chloride of soda . . Nitrate of soda Alumina and iron 1-57 0-20 0-49 0-20 1-20 0-30 1-30 The three following analyses, made by Professor Wanklyn, are of samples taken from the deep wells at Croydon, in Surrey. No. 1 is from the well in Waterworks Yard ; No. 2 from that in Mint Walk ; and No. 3 from the Old Well ; they are expressed in grains per gallon : 430 BEVERAGES. Total solid contents Silica Carbonate of lime Total Bolid contents Silica Carbonate of lime Total solid contents Silica Carbonate of lime Sulphate of lime 29-3 1-2 17-8 21-6 1-0 17-0 21-6 trace 14-1 1-8 (1) (2) (3) Carbonate of magnesia Chloride of soda .. .. Sulphate of soda Carbonate of magnesia Chloride of soda .. .. Sulphate of soda Sulphate of magnesia , Chloride of soda .. . Nitrate of soda potash Sulphate of lime 1*8 potash 1 An analysis of a well in the Red Sandstone at Liverpool gives the following figures : (Parts per 100,000.) 1-4 2-0 0-9 0-7 2-0 0'9 1-4 1-8 1-4 11 Total solid contents Organic carbon nitrogen Nitrogen as nitrates and nitrites (Parts per 100,000.) 26-400 0-020 0-020 0-416 Total combined nitroger Chlorine Hardness ( Temporary I Permanent .. 436 .. 2-680 .. 4-000 . 9-600 The three following analyses, made by Professor Wanklyn, show the composition of the water supplied to London by the West Middlesex, New River, and Kent companies respectively. The first is obtained from the Thames at Hampton, the second from the Lea and other rivers, and the third entirely from wells in the chalk ; the analyses are expressed in grains per gallon : West Middlesex Company. Carbonate of lime Sulphate of lime Silica .. 12-9 .. 2-4 New River .. 0-26 Nitrate of magnesia Chloride of sodium Company. Nitrate of lime magnesia Chloride of sodium Dmpany. 0-75 \ Alumina, &c Carbonate of lime t Sulphate of lime Silica .. 0-14 .. 12-70 .. 1-60 KentC 0-22 1 Carbonate of lime . . Water .. .. :. :: i 6 - 3 o = i8>3ina 1-03 1 Silica, alumina, &c. .. 0-28 \ 0-6 1-1 2-0 1-00 1-28 2-02 Sulphate of lime 5-37 magnesia 0*93 Nitrate of magnesia 1-20 = 12-0 soluble solids. soda 1-21 Chloride of soda 2-64 Water 0-37 ) The growing importance of deep wells as sources of drinking water renders it necessary that the geological character of the strata in which they are situate should be subjected to careful investigation, and a good deal of trustworthy and interesting information has been gathered together on this head during the last few years. The influence exerted upon the water by tlie different strata through which it passes is very great, and hence the subject is one of considerable importance. In its descent through the different beds, the water passes downwards with greater or less rapidity, according to the porosity of the strata, until at length it reaches one which is impermeable : this stratum forms a kind of floor upon which the water is stored, the quantity depending upon the thickness and extent of the strata above, and their degrees of porosity. These impermeable, or dry, strata have no influence upon the water which lies upon them further than assisting to store it. When such an impermeable bod lies upon the surface, the rain falling upon it, not being able to penetrate, runs away and collects in brooks and streams ; hence, in, districts WATER. 431 where the upper beds are of this nature, there is an abundance of stream water. In its downward course, the water is completely filtered from all suspended organic and other matters, being thus rendered beautifully clear and bright ; it also dissolves a portion of the soluble salts, generally of lime, with which it comes in contact in the various strata, and becomes, in consequence, more or less " hard." The seven most important permeable or water-bearing strata in this country are: (1) Chalk and upper Greensand; (2) Lower Greensand; (3) Purbeck and Portland beds; (4) Coral Rag and Grit; (5) Oolites and upper Lias sands; (6) Middle Lias; and (7) New Red Sandstone. The following table sets forth the principal characteristics of these water-bearing strata : Formations. Thickness in Feet. Quality of Water. Chalk - 645 to 1000 Hard Upper Greenaand Lower Greensand 100 400 20 500 Rather hard. Soft and good. Purbeck and Portland beda 60 Rather hard. Coral Rag and Grit .. 40 Great and inferior Oolites 200 450 Hard. Upper Lias sands 20 200 Soft. Marlstone or middle Lias 30 250 Rather hard. New Red Sandstone . . 2150 Soft or variable. Lower Permian beds (alternating! characters) J Variable. Soft. In endeavouring to ascertain the qualities of the underground waters derived from different forma- tions, it may be generally assumed that those drawn from limestone formations are " hard," and those from sandstone " soft." Owing, however, to variations in the nature of some of the strata in different localities, and to the greater or less proportion of carbonate of lime, carbonate of magnesia, salts of iron, &c., which they contain, the quality of the water from the same formation is liable to variation according to locality. Although this subject has been fully dealt with by various authors, it may be well to give here a brief summary of the results, as far as they have been ascertained, in different localities. (a) Water from the Chalk. The percolation of the rain through this formation, amounting in proportion to about one-third of the actual rainfall, is so exceedingly slow, that the water has abundant time to take up a large proportion of carbonate of lime from the rock itself, hence chalk water is naturally hard. It seems, from observations made on the chalk hills, that it takes from four to six months for the rain to reach a depth of 200 to 300 ft, so that the water which is drawn from this depth in summer belongs to the rainfall of the preceding winter. The total quantity of solid matter in chalk water varies from 31 to 32-5 in 100,000 parts, of which 16 '4 to 21 parts are carbonate of lime. In the case of large works, this mineral ingredient can be dealt with by Clark's softening process ; but for country villages there seems to be no plan of easy application for lessening the amount of calcareous matter, except that of boiling, by which the hardness is reduced from 24-7 to 3 7 in extreme cases. Chalk water, though hard, is very suitable for many purposes, especially for the important one of brewing. (6) Upper Greensand. The water from the upper Greensand, which immediately underlies the Chalk, is probably a little less hard than that from the Chalk itself. (c) Lower Greensand. The water from this formation, which is separated from the upper Greensand and the Chalk by an impermeable stratum known as the Gault, is remarkably pure, and decidedly "soft." Samples taken from five localities gave a mean result of 7 '9 of solid matter in 100,000 parts of water. Water obtained from this source is therefore very suitable for drinking purposes. As the sands are generally loose and incoherent, they absorb nearly all the rain which falls on their surface, except that given off by evaporation or imbibed by vegetation. (c/) Oolite Limestones. The water from these formations, which are much interstratified with Band-beds, is more or less hard, yet less so than that from the Chalk. Of the proportion of solid matter in the waters of the Oolites, that found in the fine springs of South Cerney, near Ciren- cester, which rise along the line of a large fault, may be taken as a sample. The total amount of solid matter was found to be 18 grains per gallon, of which 1 P 25 grain was of organic origin. The water from the Severn springs near Cheltenham, from the inferior Oolite, gave 6 grains per gallon, of which 2 grains consisted of organic matters. The well at Thames Head, sunk in the Great Oolite near Cirencester, yielded water containing 16 grains per gallon. And the waters of the Chelt, near Cheltenham, which rise from springs at the base of the inferior Oolite, gave 20 grains per gallon, of which 4 grains consisted of organic matter. (e) New Red Sandstone. Next to the Chalk, the New Red Sandstone, including the Bunter and 432 BEVERAGES. Lower Keeper divisions, is the most important water-bearing formation, and the water which it yields possesses an advantage over that of the Chalk in being softer, and generally capable of being used for all domestic and manufacturing purposes. From the numerous analyses that have been made of these waters in different localities in the central and north-western counties, we have the means of arriving at general conclusions on this subject. The beds of the Bunter Sandstone are wonderfully adapted to act both as natural filters and as reservoirs for that portion of the rain which sinks below the surface. This may be assumed as one- third, on an average, of the actual rainfall ; while in some districts where the formation consists of soft sandstone, or unconsolidated conglomerate, devoid of a thick covering of drift clay the amount of absorption must reach well-uigh one-half the amount of the rainfall. Owing also to its uniformity of composition, and the absence of beds of clay or marl of any importance, the whole mass of rock below a certain level, and throughout a depth of several hundred feet in some districts, becomes water- logged ; and wells sunk therein do not, as in the case of the Chalk, generally depend for their supply on the presence of fissures, water being nearly always found after the " water-level " of the immediate district has been reached. The amount of solid matter per gallon in the water of the New Red Sandstone varies from 6 to 15 grains, when it has been taken from wells not too shallow, or from those which are free from contamination by sewage pollution or other causes. It is to such a cause that the large proportion of saline and other ingredients in some of the Liverpool and Manchester wells, amounting in some instances to 24 and 36 grains per gallon respectively, is attributable. In general, the proportion of these ingredients occupies a central position between those of the Chalk and other limestone forma- tions, on the one hand, and the surface waters of mountain districts, composed of Millstone Grit or of Silurian rocks, on the other. Wine. (FB., Vin; GEB., Wein.) Wine is a generic title applied to a very large number of beverages produced by the fermentation of the juice of the grape. The art of making these has been known and practised since the remotest ages of which we have any record. The wine of grapes is, and always has been, the principal fermented drink of the southern European nations. In the United Kingdom, its consumption has been steadily increasing for many years; without the aid of figures it would be impossible to give a just notion of the immense importance of wine as a beverage in this country. In 1857, the total consumption was more than 7,000,000 gallons ; while twenty years later, in 1877, we find that it has increased to the enormous amount of nearly 17,000,000 gallons. Owing to the costliness of wine, its consumption is almost exclusively confined to the upper and middle classes, beer and spirits being the poor man's sub- stitute. In France, Spain, and Italy, where beer is not largely drunk, and where wine is much less expensive, it constitutes, as already stated, the national alcoholic beverage, being consumed alike by rich and poor. The composition and properties of different wines are influenced by a vast number of conditions and circumstances. The climate of the country, the nature of the season, the soil in which the vines are grown, the variety of grape, the mode of culture, the time of gathering, the treatment of the gathered fruit, the mode of fermenting the must, the temperature and length of time of pre- servation, all these, and numerous other considerations of minor importance, have a direct influence upon the composition and quality of wine. All wines, however, contain alcohol, but in widely varying proportions, sugar, and certain flavouring ethers to which the peculiar bouquet or aroma of each is due. Besides these, among the regular constituents of wine may be mentioned glycerine, extractive and mucilaginous matters, mineral and colouring matters, and eight distinct organic acids. Of these latter, four are formed in the juice and skins of the grape, viz. tartaric, malic, tannic, and gallic acids ; while the remaining four, carbonic, acetic, formic, and succinic acids are formed during the process of fermentation. Water is, of course, the largest constituent of wine, as of all other fermented beverages. The amount of alcohol in wine depends upon the quantity of sugar held in the must before fer- mentation, and hence varies considerably. The proportion by weight of absolute alcohol in some of the best-known wines is shown in the following table : Port .. .. Sherry .. Madeira .. Marsala .. Claret .. Burgundy 15 to 20 per cent. 17 19 17 18 15 17 8 10 8 12 Rhenish ., Moselle .. Malmsey . . Tokay Champagne Carlowitz .. . . 8 to 12 per cent. .. 8 9 .. 16 12 A good proportion of alcohol is necessary to the proper preservation of wine. Such wines as port, sherry, and Madeira, which contain nearly 20 per cent, of alcohol, cannot possibly undergo WINE. 433 after-fermentation, and may be kept for any length of time. French wines average from 8 to 10 per cent, by volume of alcohol, and require much care for their preservation. Wines containing less than this quantity do not bear transport well, and on exposure to the air turn sour from the forma- tion of acetic acid. In Spain, Portugal, and France, it is customary to add alcohol to wine after fermentation, and in these cases the whole of the alcohol in the wines does not originate from the sugar of the must. Unless the deficiency be made up in this way, precaution must be taken, by means of repeated clarifications, to remove every trace of fermentable matter from the wines, and thus to prevent the possibility of its being ruined by acetification and other degenerating influences. The sugar which ia invariably found in wine is that of the grape, which has escaped the decom- posing action of the fermentation. To this unaltered sugar is due the sweetness or "fruitiness " of some wines, and notably of port. They are called "dry" when the proportion of sugar is very small. Sugar is generally added to the must of the champagne grape before fermentation, in order to give it body, and also to keep it sparkling and prevent acetification. Only the very purest cane-sugar is ever used for this purpose, since the senses of taste and smell can easily detect the presence of impurities in the wines derived from the sugar, which cannot by any of the senses be detected in the sugar itself. Burgundy, claret, Ehenish, Moselle, and Carlowitz contain no sugar, or only a trace. The amount usually found in the most important sweet wines is shown in the following table : Lachrymse Christ! . . Patras Champagne .. .. 27 per cent. 15 7 Port .. Madeira Sherry 4 per cent. 2-5 The agreeable, vinous odour of grape-wines is imparted by a minute proportion of an ethereal substance termed cenaothic ether. This substance, when separated from the wine, is a mobile, volatile liquid, possessing an exceedingly sharp, unpleasant taste, and so powerful an odour as to be almost intoxicating. It does not exist naturally in the grape, but is formed during fermentation, and it appears to increase in quantity as the wine grows older. The faintest trace is sufficient to impart bouquet, since few wines contain more than Ta ^ 0o part of it by volume. This ether is present in all wines ; there are other ethers, however, which possess less fragrance, and which are different in different varieties of wines, giving to each the peculiar bouquet by which it is characterized ; these are present in even smaller quantities than the oenanthic ether. The formation of these is due to the action of the acids in the wine upon the alcohol, as shown in the following equation, in which ethylic acetate is formed by the union of acetic acid and alcohol : Acetic acid. C,H 3 OlO Alcohol. Ethylic acetate. C 2 H S - Water. + H 2 0. Some wines acquire their aroma partly during fermentation and partly after storage. The following table gives the average proportional quantities of some of the chief constituents of wine per litre. The figures are obtained from analyses of French, Swiss, and German wines : Alcohol (by weight) from Glucose 50-0 to 200-0 generally 80 1-5 10-0 2 Glycerine I'O Bitartrate of potash Eesidue (dried at 100) Ash .. .. 1-0 18-0 1-5 4-0 8-0 30-0 3-0 An analysis of the substances which compose the ash is as follows : Sulphuric acid, from (white wines) Phosphoric,, ( redwine8 } Hydrochloric acid, from Peroxide of iron Phosphate of alumina Lime Potash gnn. grill. grill. . 0-17 to 0-27 generally 5-20 0-155 Average 0<335 0-04 0-06 3-02 0-06 0-04 0-09 0-15 0-01 0-03 0-05 0-11 1-00 2-00 1-00 Red wines are richer in phosphates than white wines because the former remain for a longer time in contact with the seeds and skins of the grape, which are extremely rich in phosphates. Tartaric acid exists in the natural jui-e of the grape as bitartrate of potash or cream of tartar. 2 F 434 BEVERAGES. After fermentation, and when the wine is left at rest, this salt separates out, and is deposited in a thick crust upon the sides of the casks or bottles. The presence of this acid in wine tends to diminish the exciting or intoxicating effects of alcohol ; hence, as the wine gets older, it gradually becomes less acid, and stronger in proportion. Every year, therefore, added to the age of a good wine increases its strength and value. The principal effect of the presence of tannic acid or tannin is to aid in preserving wine, and to moderate the action of the alcohol. Wines containing much tannin produce intoxication much more slowly than those which contain but little. The wines of Bordeaux contain a large proportion of the astringent principle, and to this is probably due the fact that they are much less intoxicating than other varieties which are not more alcoholic. New wine contains more than its own volume of dissolved carbonic acid gas, formed during fer- mentation. This quantity, however, diminishes during storing, by diffusion through the pores of the casks, its place being taken by atmospheric air, which assists in maturing the wine. When bottled, it does not usually contain more than one-fourth of this quantity. When not in excess, its presence is believed to moderate the intoxicating influence of the wine, acting more or less as a cor- rective. It produces a gentle, stimulating effect upon the stomach, and greatly assists digestion. Wines, however, like champagne and sparkling hock, which contain much carbonic acid, are doubtless rendered more " heady " by its presence. The remaining acids, acetic, malic, pectic, &c., are seldom abundant in good wines, and have but little influence upon them beyond neutralizing, to some extent, the action of the alcohol. The general physiological effects of wine are well known. The first effect, when taken into the stomach, is to stimulate the action of that organ, producing in it, at the same time, a gentle and agreeable warmth. After a short time, the spirit penetrates into the blood, the movements of the heart and lungs are rapidly accelerated, the heat of the entire system is increased, and the circula- tion of the blood powerfully excited. If the quantity imbibed is too great, the pressure of blood in the brain becomes intense, and intoxication rapidly ensues. Vines cannot be grown in any climate. The proper development of perfume and of sufficient sugar in the grape requires a warm and constant sun, such as is to be had only in the warmer climates. The cultivation of the vine is most successfully carried on in the countries lying between the 35th and the 50th degree of latitude, and it is in these that the most celebrated vine-growing districts are situate. Colder climates produce wines poor in alcohol, though sometimes of very agreeable perfume ; they are difficult to keep, and turn sour with remarkable rapidity, since they do not contain enough alcohol to preserve them. The nature of the soil in which vines are grown exerts considerable influence upon the quality of the grape. Vines will grow everywhere, and in a fertile soil will flourish exceedingly ; but experience has shown that the value of the wine is rarely proportional to the luxuriance and strength of the vine from which the grapes were obtained. Hard, clayey soils are not favourable to the growth of grapes ; neither are damp soils, of any nature whatever. They yield vigorous and beautiful vegetation, but wine obtained from them is invariably watery and wanting in bouquet. A calcareous soil is, as a rule, highly favourable ; the culture of the grape in light, dry soils is more simple than in any other, and they yield a wine which is spirituous and of a fine bouquet and flavour. The best possible soil is that which is at the same time light and flinty. Volcanic earths yield very delicious wines, as proved by those of Tokay and the finest Italian wines. To sum up, the vine may be cultivated advantageously in a great variety of soils, provided they be light, dry, finely divided, and such as will readily receive and filter water. Heavy, moist, or clayey earths must be avoided in laying out a vineyard, and the first consideration should always be lightness and porosity. The amount of exposure to weather to which the vine is subjected has a marked influence upon it. Grapes gathered from the summit, the sides, or the bottom of a hill, may vary widely in quality ; and they vary also according as the land inclines towards the north, south, east, or west. Grapes grown on the top of a hill where they have been subject to many changes of tempe- rature and weather are less abundant, never reach perfect maturity, and produce an inferior wine to those grown on the hill-side, where they have been sheltered from these atmospheric variations. The bottoms of hills and valleys are also unfavourable to vine-growing : in such places, the air is charged with moisture, and the soil is constantly damp, the result being that the grapes are coarse, and the leaves and wood of the vine are forced at the expense of the fruit. The best possible gituation for a vineyard is on a hill-side, looking south east or south. That different seasons produce widely different wines is a well-known fact. In a rainy season, the fruit develops neither sugar nor aroma, the wine is weak and insipid, and can be preserved only with difficulty. A cold season yields a rough and ill -tasted wine; and high winds and fogs are highly detrimental to the fruit. The most favourable year for vine-growing is that in which the vine flowers in warm, dry, tranquil weather, followed by gentle rains as the fruit begins to form ; and when the development and maturation of the grape are assisted by constant heat, with occa- WINE. 435 sional showers and no fogs. For the harvesting of the fruit the weather should be very hot and perfectly dry. The finest vine-growing climate and soil is afforded by France, and this country has always produced the largest quantity of wine ; the wines of Champagne, Burgundy and Bordeaux are, perhaps, more extensively consumed than any others. The following brief description of the pre- paration of wines generally is the one commonly followed in that country. Vintage. The harvesting of the grapes is known as the " vintage." It is hardly necessary to insist on the necessity for waiting until the grapes have attained maturity, the indications of which state are sufficiently well-known. The vintage should be commenced only in fine weather and under a hot sun, and when the earth and the grapes are thoroughly dry : therefore not before eight o'clock in the morning. A sufficient quantity of grapes to fill a vat must always be gathered at a time, and at an even temperature ; failing the latter condition, they must be exposed in a warm place till the heat of the mass is uniform. Kotten grapes are cut off close and thrown away ; green bunches are left. To produce good wine, the crop must be gathered in three or four successive pickings. To give the wine more sweetness and body, the grapes are, in some districts, allowed to dry on the bunches by leaving them exposed to the heat of the sun until they become covered with a down resembling mouldiness. The bunches arrived at a state of maturity are gathered first, and produce very sweet, full-bodied wines. This picking being finished, the second is commenced, of those bunches which have matured in the meantime, and which yield finer and more alcoholic wine than the first A short interval is now generally allowed to elapse, that the combined influences of the hot days and dewy nights of the end of October may complete the ripening of the remainder, which are picked over three or four times yet, the last picking including everything that remains on the vine. The harvest will scarcely be concluded hi less than a month. In hot countries, the vintage will bear delay, especially when sweet wines are desired ; but where the grapes do not ripen readily, the vintage must precede the maturity of the crop, to avoid the injurious effect of the autumn rains. In this case, the deficiency of sugar must be made up by sweetening the must as hereafter explained. The bunches of grapes are gathered, principally by women and children, into wicker baskets, care being taken to reject those which are sour, rotten, or scorched. The contents of the baskets are emptied into small tubs placed in waggons, for transport to the place where they are to undergo the various processes of conversion into wine. Preparation of the Must. When the crop is gathered, the must id prepared by squeezing or pressing the grapes. This may be done in a variety of ways. The most crude method that of treading out the juice with the naked feet is now probably obsolete, but in many places it is done by workmen wearing large sabots. In some other places, they are crushed in small quantities at a time in shallow tubs, a tedious operation. The use of a " martyr " for the purpose is, perhaps, most general ; this is a wooden box, having a bottom formed of laths so closely set that the grapes cannot pass between them. Into this box, which is placed upon bulks above the vat, the grapes are thrown as they arrive, and are crushed by a workman in sabots. The juice runs through into the vat, while the solid matters remain behind, to be subsequently withdrawn at the side, and either added to the must in the vat or not, as occasion may require. This is repeated till the vat is filled conveniently high. The pressing of the grapes is an absolute necessity, because the saccharine juices will not ferment until liberated from the cells in which they are enclosed ; but there is no reason why the barbarous methods still existing should not be supplanted by machinery such as is used for crushing sugar-cane. A vat should be filled in at most twenty-four hours, for too long a period will entail a suc- cession of imperfect fermentations, the process being completed in one portion of the mass before it has begun in another. The best authorities agree that the grapes should be picked off the bunches before pressing, as the large stems contain but little matter useful to the fermentation of the must or the preservation of the fermented liquor. This operation is usually performed by a three-pronged fork. On the other hand, the pippins and skins of the grapes should always be added to the must, the former containing the preserving element, the tannin, and the latter the colouring principle. But in making white wines from black grapes some modification will be necessary. In the first place, taking advantage of the fact that the colouring matter in the skins is dissolved only after prolonged maceration, the pressing must be done as rapidly as possible and the skins removed. In order, however, to correct the great defect of all white wines the difficulty with which they are pre- servedthe pippins should be introduced into the must either in their natural state, or the tannin may be extracted from them by boiling and the decoction added to the must. Fermentation. In the fermentation of grape-must, the process is arrested before its completion by withdrawing the liquor from the vat, in order that it may be subsequently continued in a less degree in the casks. The juice which runs from the grapes during their transport to the works commences to ferment long before it reaches the vat, in spite of all the care taken to prevent it. In the case of highly- 2 F 2 436 BEVERAGES. brands of wine, this juice is fermented separately to produce the choicest varieties, but as a rule it is added to the juice obtained by pressing, and all is fermented together. The fer- mentation is conducted in vats of masonry or wood, the former being preferable, as they require less repair, maintain a more constant temperature, and are less exposed to accidents. The latter, however, when free from iron inside, are useful for small quantities. The vat must be scrupu- lously cleaned before admitting the must. Stone vats are washed with warm water, and coated with milk of lime ; wooden ones are washed with warm water, and then scrubbed with brandy. These precautions are needed to ensure the destruction of fungoid life and acid or fatty products that would injure the must. The established conditions of fermentation are a certain degree of heat, contact with the air, and the existence of a vegeto-animal principle, and of a saccharine principle in the must. The most suitable temperature is about 19 (66 F.) ; it is too slow below this point, and too rapid above it, ceasing altogether under the influence of great heat or great cold. If the tempera- ture of the surrounding air does not equal at least 15 (59 F.), it must be raised to this point by artificial means, and the must heated by mixing some boiling must with it, or better, by intro- ducing, as in Burgundy, a bath cylinder. This precaution concerning the temperature is absolutely necessary, and certain results cannot be counted upon without it. The fermentation also is slower in proportion as the temperature at the time of the vintage was lower. This inconvenience also is obviated by heating the must and raising the surrounding temperature to 15 to 19 (59 to 66 F.). Experience proves that grapes gathered in the morning are slower to ferment than those plucked after noon under a hot sun and in fair, clear weather. Dews, showers, and slight frosts also hinder fermentation ; hence the necessity for observing the conditions of weather before alluded to. Air is favourable to fermentation, and is necessary to its initiation, though it may be dispensed with subsequently. It is nect ssary, on the other hand, that the carbonic acid liberated shnll have free egress ; but this disengagement entails great loss of alcohol and of bouquet, so that it is well to cover the vat with planks, on which cloths are spread in such a manner that the contents are preserved from contact with the cold outward air, still leaving a small outlet for the generated gases. The fermentation is thus regulated ; the temperature is maintained at a higher point ; the loss of alcohol and acidification of the " head " are prevented ; the aroma and bouquet are pre- served ; and the fermentation is maintained under varying atmospheric conditions. The fermen- tation is also more rapid and complete according as the mass is larger ; but against these advan- tages, and the additional one that the wine keeps better, must be counted the facts that the larger vats require longer to fill, and that the increased heat may cause the volatilization of a portion of the bouquet. Very sweet grapes yield sweet and full-bodied wine, because the ferment is not in sufficient quan- tity to decompose all the sugar; less sweet grapes may require sugar to be added to the must to nourish the action of the ferment and to employ the whole of it in producing alcohol. Very thin must is as difficult to ferment as very thick must. The mean consistence should be 10 '5 to 11 '5 B. (about 1 080 sp. gr.). When the must is very watery, the resulting wine is weak and very liable to change. Cold countries, wet lands, and rainy seasons produce grapes containing more water and ferment than is necessary to decompose the sugar formed in the fruit, and the wine is liable to turn sour in consequence of the superabundance of ferment remaining after the spirituous fermentation. Mention has already been made of a means adopted for correcting this evil. In sugaring the must, it is necessary to remember that cane-sugar does not undergo alcoholic fermentation till it has arrived at a more hydrated condition than the sugars of fruit, or glucose. To avoid the delay thus occasioned in the fermentation, it is well to transform the crystallizable sugar before introducing it. Tartaric acid is preferably employed for this purpose, and the sugar solution should be boiled in the must for two hours in presence of 2 per cent, of this acid. If the grapes were insipid and flat, only a partial neutralization by the aid of chalk is needed, while with very acidulated musts the tartaric acid should be completely neutralized. By this plan is obviated the fault ascribed to the sweetening of some musts that it leaves a sickly taste in the mouth, due to the fact that the sugar used has not been entirely decomposed, because then all the added sugar is transformed into alcohol as rapidly as the grape sugar itself. Neither need there be any fear that the addition of the sugar will postpone the commencement of the fermentation ; therefore it may be added as early as desired, instead of waiting till towards the end of the operation. Obviously the sugar may also be converted by means of sulphuric acid or phosphoric acid on condition that the subsequent neutralization be complete ; but tartaric acid is specially named, ns it is normally found in the fruit of the vine, and a solution of it may be economically prepared by treating dry lees, which abound in vine countries. The fermentation first manifests itself by little bubbles which appear on the surface of the must : little by little it raises the centre of the mass, agitates the whole, and produces more or less effer- vescence, due to the liberation of carbonic acid. The suspended matters are distributed, raised, and WINE. 437 precipitated until one portion settles on the bottom and another portion collects on the surface to form the "head." The fermentation commences as soon as the vat is filled, and lasts ordinarily from twenty-four to thirty hours, with a temperature of 30 to 32 (86 to 89 3 F.) in the centre. The volume of the mass increases considerably. The " head " raises itself, cracks open, and disengages abundance of froth ; heat develops in the liquor in proportion to the mass, and the colour is in- tensified. Then the symptoms diminish, the head sinks, the liquor clarifies itself, and the work is nearly terminated. The heat, being greatest in the centre, must be equalized by pressing down and agitating the mass. The effervescence, agitation, and heat observable in the must are more intense when the skins, pippins, and stems are present. If the movement relaxes, the vat is mashea and the head precipitated several times. This is done by means of a stirrer, but it must be dispensed with when the skins exhibit any change. Acidity in the head is prevented by protecting it from the action of the air ; and by precipitating the froth in the bath, the ferment it contains becomes mixed with the liquid and nourishes the fermentation. Tlie more completely the grapes have been crushed and the more carefully the saccharine fluid has been extracted from the cells, the more regularly the alcoholic fermentation develops itself. Sometimes instead of mingling the skins with the must in the vat, a lid pierced with holes ia fitted to it in such a way that the skins are thus kept immersed in the must. This arrangement has borne advantages and some drawbacks. Clearly it avoids the necessity for agitating the mass, since the solid particles are plunged into the liquid and the wine reaches the surface. A second cover surmounts the vat, but if it does not close hermetically and the air obtains free access to the wine, there is danger of its causing acidity. The fermentation may be left to complete itself without any manipulation, provided the second cover be perfectly closed, preserving only an exit for the generated gas by means of a bunghole of sufficient size. This plan, however, is not in favour with the best authorities, who declare that considerable advantage is derived from mashing the mass while in the vat, since the wines gain in quality by the agitation. The carbonic acid which disengages itself from the mass, and the deleterious effects of which are well known, displaces the atmospheric air resting on the vat. and then falls to the bottom of the room by reason of its density. Ventilation must be provided with the utmost care in order to avoid the risk of suffocation to the workmen. Milk of lime and alkaline solutions absorb it. The proportion of alcohol produced is in accordance with the sugar which the fruit contains, and is, in consequence, very variable, since the musts may have any density from about 8 to 18 B. (about 1-060 to 1-143 sp. gr.). The proper moment for drawing off the wine and placing it in casks is when the fermentation has rendered the presence of the sugar insensible and replaced it by alcohol, though all the sugar has not absolutely disappeared, but suflBcient still remains to excite the complementary fermentation in the casks. Concerning the colour of the wine, it may be remarked that it is more intense according as the fruit has been more pressed and longer fermented, as the grapes are riper, and as the wine is more alcoholic. As a general principle, lively and prolonged fermentation ia destructive of bouquet and aroma, which constitute the merit of some wines; on the contrary, a very complete fermentation should be allowed to wines whose principal quality is alcoholic strength. Finally, energetic mashing, often repeated, prevents change in the " head,'' provided that the must has entered freely into fermentation under the influence of a sufficient temperature and with a suitable proportion of sugar. The disengage- ment of carbonic acid will be such as to obviate any reason to fear the access of atmospheric air, if the mass does not remain in the vat too long after the liberation of the gas is finished. The operation of racking the wine will presently be considered, but a few words must first be devoted to the " fortification " of wines, and the results to be expected from it. Fortification. This consists in introducing a certain proportion of alcohol into the wine for the purpose of strengthening and preserving it, the alcohol opposing secondary fermentation by paralyzing the action of the ferment and precipitating the albuminoid matters ; it also improves the condition of weak and acid wines. The operation may be performed either in the vat or in the cas"ks, preferably the former. The must is fortified by adding a proportion of sugar corresponding to the alcoholic strength desired, or by adding alcohol itself when the fermentation is approaching its end, or about twelve to fifteen hours before racking. Wine in the cask is fortified by an addition of alcohol or by a mixture with very alcoholic wines. The wine may also be submitted to congelation, which removes a portion of its water in the form of ice. Fortification sweetens too acid wines, in that the alcohol precipitates the excess of cream of tartar, and combines in time with the free acids present to form ethers. It also affects the colour of red wines, alcohol being a solvent of the violet principle of the grapes. The colour of the wine is due to a mixture of this normal violet with a red colour due to the effect of the air and acids. It therefore follows that better results on this head are obtained by fortifying in the vat, for by direct fortification in the cask the red tint is diminished and precipitated in the lees. It is evident then, that independently of its direct action, ale >hol de-acidizes too acid wines, favours the formation of ethers, increases the colour, and gives a body to the wine. These are 438 BEVERAGES. sufficient reasons in its favour ; but the direct addition of alcohol must almost always be condemned. Not only are the most detestable compounds brought into the market after treatment with alcohol, but the plan has also this great disadvantage, that wines so treated cannot possess that degree of homogeneity which arises from fermentation, and which is one of the principal merits of natural wine. Ill-advised, however, as the direct addition of alcohol is, it is, nevertheless, only too often resorted to, because the cost of the alcohol produced by fermenting additional sugar in the must is a trifle higher than the commercial price of manufactured alcohol. It does occasionally happen, however, that good may result from the addition of alcohol to the must towards the end of the fermentation in the vat. Sacking. From the preceding observations it is evident that the moment for racking wine cannot be submitted to fixed and invariable rules, but that it will differ with the climate, the season, the quality of the grapes, the nature of the wine to be produced, and other considerations which must not be lost sight of. The sinking of the head is not a sufficient sign, as some wines should be drawn off before this happens, while others improve by remaining for some time afterwards. The cessation of sparkling and froth, indications drawn from the odour, taste, colour, cooling, and density, do not always form a safe guide, though the last mentioned does, in the majority of cases, mark the precise moment. Wines for distillation must be thoroughly fermented ; while weak, perfumed winea need less, notably some white wines whose speciality is to be sparkling. Racking must invariably be performed when the sweet taste has become insensible, and is replaced by a vinous flavour. The lowering of the density to or 1 B., cannot always be considered a proof of the end of the fermentation, since the proportion of alcohol and other matters renders it inconstant. Chaptal gives the following rules : 1, The must should ferment for a length of time proportionate to the sugar it contains ; 2, It should ferment less for sparkling wines, and be introduced into the casks immediately after pressing ; 3, It should ferment less as the colour is weaker ; 4, It should ferment less as the temperature ia higher and the mass greater ; 5, It should ferment less as the wine is to be more perfumed ; 6, It should ferment longer if it is to be distilled ,- 7, It should ferment longer as the temperature was lower at the time of vintage ; 8, It should ferment longer as the wine is to be more coloured ; 9, And it should ferment longer in small vats than in large. Consequently the vatting may vary from 24 hours to 12 or 15 days. Nothing is more arbitrary in practice than the moment for racking, but there is no doubt it may take place the instant the active fermentation ceases, and the vatting need never be prolonged beyond 72 hours for very rich wines, and 30 to 36 hours for delicate wines ; while the latter period much more than suffices for very light wines or those for immediate consumption. The racking is done in a very simple way, either by a siphon or by a tap placed in the bottom of the vat, at the interior orifice of which a grating or birch broom has been placed to retain the pippins and impurities. The wine is caught in large tubs, and then filled into casks which have previously been scrupulously cleaned. When the vat has been emptied of wine, a residue is found in it composed of stems, skins, and pippins, as well as a variety of vegetable debris, froth, and albuminoid matters combined with tannin. The win* contained in it is removed by pressure. The mass is placed in the press, and the wine which runs from it is added to that already obtained without pressure. After the first pressing, the mass is turned over and pressed again till the fourth time. The product of the first pressing is the strongest, that of the last is the hardest, the most sharp, and the most deeply coloured. Often the products of these several pressings are mixed in separate casks to produce a deeply coloured wine that will keep very long ; at other times it is mixed with the unpressed wine to give it strength and a slight astringency, and to obtain one uniform product from the whole vintage. The solid mass of skins, &c., assumes almost the hardness of stone when well pressed, and is applied to several purposes. In some countries, it is used for brandy making ; in others it is treated with water to form a thin vinous drink for the labourers. Elsewhere, it is employed in the manu- facture of verdigris ; and again, of vinegar. It is widely applied to cattle feeding, and may be burnt to produce alkali. The pippins form excellent poultry food, and yield oil. When the must has undergone its due period of active fermentation and has been placed in casks, it has by no means reached ite last degree of elaboration. There is still a modified amount of fer- mentation to be undergone, after which the inert alcohol deposits itself at the bottom of the vessel with the greater part of the insoluble suspended matters, thus constituting the " lees." In order that the wine may acquire its due degree of spirit, it is essential that all the convertible sugar be transformed into alcohol by the slow fermentation which follows the active process in the vat ; besides which, it must be made to keep by separating the deposits, the foreign suspended matters, and the soluble substances, which might cause an alteration in it. The work thus entailed consti- tutes the duty of the cellarman, but before alluding to the several points involved, it will be neces- sary to say a few words about the cellars where the wine is worked and stored as well as about the preparation of the tubs and casks for its reception. Maturation and Storage. Vaults and above-ground Cellars. The following rules should be observed with regard to a wine vault : WINE. 439 1. The vault should face the north, the temperature being then much less variable ; 2, It should be dtep enough to ensure the temperature being constant; 3, Its humidity must be constant without being too great, for excess of moisture mildews the papers, taps, &c., while dryness may cause the casks to open and let out the wine ; 4, The light must be very subdued ; 5, It must be absolutely secure from disturbance, for the shaking caused by the passage of waggons along a road, or by a thunderstorm, stirs up the lees, mixes it with the wine and provokes acidification ; 6, All green wood, vinegar, or other substances likely to ferment must be kept away from the vault. Accordingly the vault must be excavated several fathoms beneath the surface of the earth ; the outlets must face the north ; it must be distant from all roads, factories, streams, &c., and must be vaulted over. The best vaults are generally those cut in solid rock. Above-ground cellars are built where the soil is sandy. They should unite as far as possible the same conditions as the underground vaults. The Bordeaux cellar is made in the following way : It is built as near to the fermenting vats as possible, of varying length, and about 20 to 25 yards broad. The floor may be on the same level as the earth outside, but the air is fresher when the floor is lowered a few inches, in the case of dry soil ; but where the soil is wet it should rather be raised a little. It should be shaded on the south by tall trees or by a building ; the windows, of very small dimensions, are pierced in the north wall. It is ceiled with plaster or planking. Four rows of casks are placed in it, two down the middle and one along each side, supported on long beams a few inches above the floor. Receptacles for Wine. In principle, the most capacious and most tightly closing vessels are the best. Use is chiefly made of casks, of various sizes, constructed of oak, whose principal inconveniences are that they sometimes present soluble substances to the wine, and are more or less porous. When made, the wine i* stored in casks or glass bottles. In any case, the receptacles must be thoroughly cleaned in good time before they are required. Those having an unpleasant smell after cleaning should not be used. The best mode of cleaning is as follows. The cask is first soaked in cold water, and then in hot water to swell the wood and close all interstices. It is afterwards thoroughly washed with a mixture of sulphuric acid with fifteen times its weight of water, and finally subjected to two washings, the first in boiling, the second in cold water, to remove all trace of the acid. During the " insensible fermentation" in the casks, a more or less abundant froth forms on the surface of the liquid, and must be carefully removed. At this time, therefore, care is taken to keep the casks constantly full, in order that the scum may escape at the bung-hole which is only im- perfectly closed by a leaf or by lodging the bung loosely on it. In some countries, the level is adjusted every day during the first month, every four days during the second, and then once a week till the wine is drawn off. The intervals are modified elsewhere, the object being to let out the scum and prevent the action of the air on the wine while the disengagement of carbonic acid is relaxed or spent. The causes which diminish the contents of the cask are evaporation and absorption by the wood of the cask. The casks should be hermetically closed as soon as the generation of carbonic acid is not sufficient to oppose the free access of the air, but a vent-peg should be inserted for the purpose of letting out the gas now and again. The working of wine consists in. a gradual and complete purification, performed after the fermentation, and intended to eliminate all convertible foreign matters, but especially the soluble and insoluble nitrogenous matters. For all wines of good quality the filling up should be done with the same wine, some being re- served specially for the purpose, but with common wines it may be done with the press liquor. la any case, the vessel containing the complementary wine should not be left open. It is unnecessary to state that the casks ought to be raised on stands in the cellar, at such a height as to render the drawing off as easy as possible. They should also be placed perfectly hori- zontal, for if tilted up at the back, the lees collect at the front, rendering it necessary to place the tap inconveniently high in order to prevent it from running out with the wine ; and, if raised at the front, it is impossible to draw off the whole of the clear liquid ; whereas, when lying perfectly horizontally, the lees collect in the centre of the lower cavity, without being disturbed when the wine is racked. The casks, thus disposed, roust be inspected frequently, in order that any accidents may be discovered and remedied at once. This is especially necessary during the month which precedes and follows the equinoxes; at these times, the wine is particularly subject to undergo fermentation, especially new and white wines. If allowed to ferment, the wine exercises considerable pressure in the casks, the staves frequently giving way unless an exit be made for the carbonic acid gas, or, rather, unless several litres of the wine be immediately removed from the cask. During the equinoxes also, the casks are liable to be rotted by vapours exhaled from the ground ; this is especially the case in deep cellars. Great care must be taken, too, to see that none of the casks become leaky or worm-eaten ; large quantities of wine may be lost from these causes. Drawing off. There are so many influences which causu the lees to remingle with the wine after having deposited itself at the bottom of the vessel, that the first care necessary after the conclusion of the complementary fermentation, is to separate the wine from the deposit by drawing it off. 440 BEVERAGES. This is performed at various times according to fancy, but the moot reliable rule is that weak wines should be drawn off iu winter, medium wines towards the end of that season, and strong, full-bodied wines in summer. The operation is repeated as many times as may be necessary for the purification of the wine. It is best performed by means of a siphon, or a simple air-pump. As long as a wine preserves its colour, flavour, and aroma, there is no necessity for re-racking it ; bat as soon as it begins to lose its transparence, becoming turbid and flavourless, it must at once be drawn off into another cask, which has been well sulphured the moment before. The effects of sulphuring are pointed out in the ensuing paragraph. Sulphuring. This operation consists in burning sulphur in the casks. Its first effect is to make the wine thick and its colour disagreeable, but the latter returns in a short time, and the wine clarifies itself. Its object is to prevent acidification and all ulterior fermentation. It also displaces the air. Wines are sometimes sulphured without being withdrawn from the cask. A small quantity is drawn off, and the sulphured wick inserted at the bung-hole and burned just above the surface of the wine. While the empty portion of the cask is filled with the sulphurous gas, the bung is replaced, and the cask agitated violently, in order that the gas may be entirely dissolved. The cask is then refilled with wine. Another method of sulphuring wine consists in introducing a small quantity of a solution of the sulphurous gas in water. Clarification. The processes of racking-off and sulphuring remove a large portion of the im- purities of a wine, but there still remain particles of suspended matter, which must be precipitated by a process of artificial clarification. This process not only removes suspended matters but aids in precipitating dissolved impurities, even after a considerable lapse of time. Hence it constitutes a powerful means of improving and preserving wines, and cannot possibly be dispensed with. The substances most commonly employed to effect this clarification are fish gelatine, the whites of eggs, blood, and various other substances artificially prepared. When fish gelatine is employed, it should be chopped into small pieces and stirred up with a little wine aud an equal weight of tartnric acid ; it swells, softens, and forms a glutinous mass. This is thrown into the wine in small quantities and with much stirring, after which the wine is left to stand. During this time, the gelatine combines with the tannin of the wine and falls to the bottom, carrying with it all particles of suspended matter, and leaving the wine clear and bright. Five grammes of fish gelatine is sufficient to clarify 150 litres of wine. To prepare it for use, 5 grm. may be dissolved in 7J decilitres of white wine and made up to the litre with brandy ; this preparation will keep indefinitely if kept tightly corked. In warm climates, egg-albumen may be used with advantage in winter ; the whites of five or six eggs are sufficient to clarify 150 litres of wine. They are beaten up with a pinch of salt, and then thrown into the cask. Eggs which are not absolutely fresh must not on any account be employed. Blood-albumen may be substituted either for fish gelatine or white of eggs ; one portion is coagulated by the alcohol, and the rest combines with the tannin and colouring matters of the wine. Its use tends greatly to improve the colour of the wine, especially if its colour has become altered by age. In order to preserve blood, it may either be mixed with an equal portion of alcohol at 58, or it may be dried. Many different powders, consisting of albumen in various forms and bearing particular names, are prepared aud vended in France as clarifying powders. Classification of Wines. Wines may be divided into several different classes, according to the point of view from which the classification is regarded. The most obvious division is that of colour : they may be either white or red. White wines are prepared from both white and black grapes, but the juice after expression is not allowed to remain in contact with the skins and seeds of the black variety, or it will extract the colouring matter. Ked wines are made from the black grapes only, and the must is allowed to lie upon the seeds and skins until it has become of the desired colour. Or wines may be classed again as "sparkling" or "still" wines. The qualities of sparkling wines are afforded to them by placing in the bottles a little cane-sugar, and so causing them to undergo a second fermentation ; still wines are those which have not received this addition of sugar. A very common classification of wines is as " dry " or " fruity " ; the former being those, like Rhenish wines, which contain little or no free sugar, and the latter those, like port and sherry, which contain much sugar and have a sweet or " fruity " flavour. Wines may be further spoken of as simple or compounded, or mixed, the latter being, of course, mixtures of two or more simple wines made for the purpose of blending their distinctive qualities of taste, bouquet, and colour. Such mixtures are much drunk in this country. The wines of the South of France are strongly alcoholic, stimulating, and of a warm flavour. Some of them are highly aromatic and saccharine and all possess a fine, delicate aroma. Those of Champagne and Burgundy are moderately alcoholic, full-bodied and delicately perfumed ; they are both red and white. The Spanish wines, port, sherry, and Madeira, are the most alcoholic wines made ; the former is dark in colour and the two latter are white or golden ; all of them have an exquisite bouquet. The wines from the Rhine are dry and acid, of a light flavour, and poor in WINE. 441 alcohol, and of a fine golden colour. Bordeaux wines are tonic and astringent, nutritive, stomachic, aud of a delicate flavour and perfume. Those of Tokay, Alicante, Malaga, Malvoisie, and Cyprus are very saccharine, tonic, and stimulating. Preservation of Wines. The preservation of wine presents no serious difficulties provided that certain rules be carefully attended to. The principal conditions of success are the following : 1. The more alcohol a wine contains, up to 18 or 20 per cent, by volume, the better it will keep. 2. It should also contain a good proportion of free sugar. 3. A wine, though rich in alcohol and poor in sugar, is more liable to spoil in proportion as it contains germs of nitrogenous organic matter, whether soluble or insoluble, coagulable or non- coagulable by heat. From these conditions, it will be seen that when wine contains an average proportion of alcohol, or of alcohol and sugar, but when by repeated rackings all suspended matters have been removed, and if it contain sufficient tannin to effect the removal of soluble albuminous substances, and the processes of clarification have been scrupulously followed out, there is nothing to prevent its being preserved for an indefinite length of time, provided it be kept from the oxidizing action of the air. The principal alterations and maladies to which ill-made or carelessly stored wine is liable are acetous and viscous fermentation, excess of astringent or of colouring matters, ropiness, and bitter- ness. These may all be avoided by careful attention to the rules which have been given for the proper conduct of the various processes. Testing Wine. The good or bad qualities of a wine may be recognized by the application of three senses sight, smell, and taste. An eye accustomed to the examination of wines can readily discover whether the colour is homogeneous or not, and whether it is natural or artificial. By the sense of smell, the aroma of different wines is distinguished one from another ; this method of examination becomes an almost infallible indicator when the organs of smell are extremely sensitive. The sense of taste, when carefully exercised, is the most to be relied on. When a wine is pure and un- adulterated, the different component principles are blended together, forming a perfectly homogeneous whole, which leaves one flavour only upon the tongue and the roof of the mouth ; but when the wine is the result of a mixture, the constituents are not intimately combined, but merely loosely mixed. By keeping such wine in the mouth for a short time, the warmth volatilizes the lighter and more volatile constituents, rendering them at once sensible to the roof of the mouth, while the extractive and heavier matters are made evident to the tongue and lower part of the mouth ; if the wine has been diluted with water, it is detected at once by a practised taster, by a sensation of flatness and insipidity. Physical and chemical instruments, such as thermometers and oanometers, are frequently employed in testing the qualities of wines, in order to ascertain their vinous or saccharine richness. Mixing Wines. The mixing of wines is performed in order to rectify certain defects by bringing together two opposite qualities. Thus red wines are mixed with wines of too light a colour ; light wines, containing little alcohol, with stronger wines, in order to ensure their preservation, and so on. These mixtures, when judiciously made and in proper proportions, always produce wines superior in quality to either of the two originally mixed ; they are generally more wholesome and more agreeable. The art of making such mixtures is a difficult one, since not only have the appearance, the taste, and the smell of the wine to be consulted, but also the taste of the consumer ; hence it is not possible to base it upon any definite rules. The wines of Southern France are dark and heavy, but when mixed with white wines, obtained from a light, chalky soil, they yield splendid wines of a beautiful, brilliant colour. If a fresh, sweet white wine is mixed with an acid wine, the product is also one of very good quality. A small quantity of a new wine, or two or three years old, added to an aged wine which has lost its fresh- ness, or has begun to turn bitter, completely restores it, and often quite removes the bitter flavour. Highly coloured red wines, when mixed with white ones which have become yellow, are much improved in flavour and quality. The practice of mixing wines not only improves and assists in preserving them, but also renders them capable of being transported for great distances without fear of injury, which could not possibly have been the case with the unmixed wines. The well-known harshness of some Bordeaux wines is frequently corrected by adding Hermi- tage, and colouring with those of Cahors, Gard, and He'rault ; these mixtures can only be made when the wine is new, in order that, after mixing, they may undergo an insensible fermentation, by which the added wines are closely united with the Bordeaux ; the result is a fine wine commonly sold as Medoc. It will thus be seen that the wines to be used for mixing, and their proportions, vary extremely, and must be adapted to the different tastes of different consumers. The taste of the majority of Englishmen is quite different from that of the Eussians, and that of the Euasians is different again from that of the Germans ; and therefore the wine-dealer is obliged, in order to satisfy all demands, to make a profound study of this question of mixtures. He has also, by various means, to increase the strength of his wines, especially if they are destined for the English market ; this he frequently 442 BEVERAGES. effects by adding alcohol, in proportions of 2 to 5 litres to each cask of wine, or by provoking a second fermentation in it by adding unfermented must, in close vats. In the South of France, the wines chiefly used for mixing are those of Alicante, Bernicarlos, Hermitage, Rousillon, Gaillac, and others. In Burgundy, when the vintage has been a small one, the deficit is made up by adding equal portions of the wines of Tavel, Cher, Rousillon, or Narbonne, and then a sufficient quantity of water to bring the mixture to the regular alcoholic strength. These wines, when brought together, speedily undergo a continuation of the fermenting process, which renders them absolutely homogeneous, and produces a wine which cannot be distinguished from the finest Bordeaux. For a wine of the first quality, the proportions of the mixture are : Wine of Cher 1 pipe. Marseilles 1 ,, Bordeaux (white) 1 Rousillon 10 gala. For a wine of the second quality : Wine of Touraine 1 pipe. Rousillon 10 gals. And for an ordinary wine : Wine of Rousillon 1 pipe. Burgundy 30 gals. River or rain water 1 pipe. Alcohol 5 quarts. Good vinegar 1 quart. Tartaricacid 500 grm. Tannin 59 When the wine is of too deep a colour, a dry, white wine may be substituted for the Burgundy. It is advisable to allow the mixture to stand for a month or more. It is often the practice to send mixed wines into the market as soon as they are made ; but this is a great mistake, since the elements of the mixture have not had time to become properly mixed and to form a homogeneous whole. A month is generally sufficient to effect this, but in the case of some wines a much longer time is requisite; others, indeed, never mix at all, the particular taste of each single wine is distinguishable after a con id .Table lapse of time. When a wine possesses certain characteristics which render it of superb quality, it ought never to be mixed with other and inferior wines, as is too frequently the case. An old wine, unless it is deteriorating and lacks freshness, ought not to be mixed with wine of less than two years of age, at the risk of losing both bouquet and colour. No wine which has undergone alteration or deteriora- tion of any kind should ever be used for mixing, or the disease will inevitably spread until the whole mixture is ruined. The improvement of a wine is commonly effected in one of two ways : either by natural means, such as mixing it with one or more different wines ; or by an artificial method, such as imparting to the wine itself, or to the mixture, those particular principles which are lacking. Examples of the first method are afforded by mixtures of the wines of Touraine and Cher, made for the purpose of improving the former ; by mixtures of different brands of Burgundy ; by mixtures of strong and weak wines, or of a wine which is becoming enfeebled by age with another of the same brand but some years younger, &c., &o. By the second method, wines lacking sweetness are improved by the addition of syrup ; wines which are too sweet, by the addition of a little solution of tartaric acid; those wanting in bouquet, by affording to them the particular bouquet by which they are characterized ; and those which have none at all, by the addition of any which may be desired. By these and various other methods, and with the exercise of a good deal of judgment and experience, the wine merchant is able to remove or cover any defect to which a wine is liable. In these processes of mixing consists the great art of cellar management, and to such an extent is it carried on, both abroad and in England, that it may be confidently asserted that few wines ever reach the consumer in an unmixed or natural state. Strengthening Wines. Wines are often strengthened by the addition of alcohol, for the purpose of rendering them preservative and preventing alteration. The fortification is generally performed with Montpelier spirit, of 86; it is preferable, however, to use spirit of about 58, obtained by distillation. This method of fortifying wines is very defective, since it imparts to them a crude, rough flavour and odour, which will not permit them to be used for a very long period. To avoid this, the following mixtures may be employed with advantage, instead of the raw spirit : Water 70 litre*. White sugar 6 kilos. Carbonate of eoda 30 grm. Pure tannin 15 Alcohol (86) 25 litres. WINE. 443 Or better still : Water 57 litres. White sugar 6 kilos. Carbonate of soda 30 grm. Pure tannin .. , 15 Brandy (58) 38 litres. In making the first of these preparations, the sugar and carbonate of soda are dissolved in the water, and the spirit is then added. For the second, the sugar, previously dissolved on the fire in a little water, is added to the brandy, then the carbonate of soda, also dissolved in a little water, and finally the rest of the water is added. These preparations improve much on being kept. Their use will preserve wines from many maladies, and will even restore those which have been suffered to spoil. Imitation of Wines. The practice of adding various substances to inferior wines, in order to pass them off as wines of great age and value, has become extremely wide. All sorts of tinctures and infusions are employed in making these imitations ; and it will be well to give here the recipes from which they are chiefly prepared, and then to point out briefly the methods used to imitate certain wines of well-known brands. The following are a few recipes for these tinctures : Tincture of Iris. Alcohol (50 to 58) 1 litre. Water J Florentian iris (powdered) 125 grm. Allow to stand for twenty-four hours ; then distil to obtain 1 litre. Tincture of Strawberry roots. Alcohol (85 to 90) 5 litres. Dry strawberry roots (powdered) 500 grm. Tincture of Iron. Oxide of iron 500 grm. Crystallized tartaric acid 500 Water 2 litres. Dissolve these by heat. Tincture of the dried husks of nuts. Alcohol (85 to 90) 5 litres. Dried husks 500 grm. Infusion of Raspberries. Alcohol 10 litres. Raspberries (ripe and picked) 10 kilos. Tincture of Almonds. Alcohol (85 to 90) 5 litres. Essence of bitter almonds 5 grm. These preparations, after about a month or so, may be utilized in imitating various different wines. If it be required to make Burgundy, Macon, or Bordeaux, those wines are chosen which most resemble the one required in age, colour, strength, &c. For Burgundy, a small quantity of the infusion of raspberries is added to each cask, either alone or with a little of the tincture of almonds. For Macon, the infusion of the husks of nuts and the tincture of strawberry roots are employed, a litre of each being added. For Bordeaux, the tincture of iron is used to produce the characteristic roughness; 1 to 2 litres of the infusion of raspberries to every cask of 280 litres ; and a minute quantity of the tincture of iris to give the bouquet. The exact quantity of these tinctures required to give the right flavour or bouquet must be left to the dealer, as they depend entirely upon the nature of the wines dealt with. Various shades of colour are imparted to wine, when necessary, by adding small quantities of tinctures made from different foreign woods. Some wines, owing to age, begin to lose their characteristic qualities ; this is frequently prevented by adding to it wine of the same brand, but perfectly new, by which means the old wine regains its freshness, colour, or bouquet. As a rule, however, the older the wine the finer does it become and the more agreeable is it to the palate. For this reason, many plans have been resorted to in order to make a new wine pass for an old one. These methods rarely succeed in deceiving a practised taster, and since they almost always injure the w:ne to some extent, they are not by any means to be recommended. It is seldom absolutely necessary to impart fictitious colours to wines, but it is the custom to do so in order to gratify the eye of the consumer ; this is especially the case in seasons when the grape has not arrived at full maturity, and the wine is, consequently, of a poor colour. Many colouring preparations are made for this purpose from different Indian and Brazilian woods, and from the 444 BEVERAGES. seeds and berries of the elder-tree, privet, danewort, whortleberry and other plants. By tho use of such preparations any desired shade of colour may be easily obtained. A much better means of imparting colour will, however, be found in the employment of red hollyhock flowers, dried and picked, and steeped in either red or white wine. This preparation, made when required or a few days previously, will serve to give a white wine any desired shade of red ; and if kept for some time, it becomes capable of imparting a very fine brownish-red tinge. Its special advantage is that it cannot be detected in wine by any process whatever. By fermenting mulberries, a preparation may be made, having not only a magnificent colour, but a very fine perfume also ; by mixing it with brandy, a colouring medium is obtained which is quite equal to the preceding, and of a far superior aroma. These substances, and some others, have been employed in France for colouring wines with the most complete success. The method of making the first-mentioned colouring preparation, viz. that from the hollyhock, is as follows : To operate on a large scale, a cask is raised slightly from the ground on a wooden stand ; this cask has a trap-door in its- bottom, for the introductiou and withdrawal of the flowers, and also a perforated false bottom, placed about 4 in. from the real bottom, and a stop-cock midway between the two. It is then filled to nine-tenths of its capacity with dried and carefully picked leaves of the red hollyhock flowers, and wine poured upon them until the cask is quite full, when it is covered over. After a period of eight days or more, the wine is drawn off into another cask and the flowers allowed to drain before being covered with wine afresh; the second infusion is added to the first. A little tartaric acid is added to the tincture in order to brighten the colour, and also a quantity of alcohol, after which the whole is allowed to age. The flowers may be infused once or twice more, and should finally be well pressed to extract the remaining drops of wine. Three hundred grammes of the leaves are sufficient to impart to 100 litres of white wine, a fictitious colour resembling that of the wines of Narbonne. In order to know what quantity of the flowers is necessary to heighten the colour of a light wine to the required degree, a litre of the wine is taken and such a quantity of the tincture is added to it as is necessary to produce that colour, the quantity being carefully noted. The correct proportion required to colour 100 litres, or any other quantity, can then be readily deduced. The method generally employed to extract the colouring mutter from the berries of the elder- tree, privet, danewort, whortleberry, or mulberries, consists in bruising the fruit and subjecting it to fermentation, with the addition of a little water if necessary. Or the fruit may be infused simply in alcohol, at from 65 to 85 ; such infusions have a finer aroma than the products of fermentation, and they are more readily preserved. A little solution of tartaric acid may be added to them with advantage about once every month. Fruity or liqueur wines contain less water and more sugar and alcohol than the dry wines, and have also a stronger aroma. They are generally of a somewhat syrupy consistence. Owing to their large proportions of alcohol and sugar, they have the property of keeping for many years without undergoing sensible change. The best known and most esteemed of these wines are those of Alicante, Grenache, Cyprus, Lacrymse Chrihti, Madeira, Malaga, Port, Sherry, and Tokay. The liqueur wines of commerce are, however, almost always imitations, made at Cette or Mont- pelier. They are made by mixing different wines with alcohol and sugar, and some aromatic infusion, in such proportions as agree with the character of the wine imitated. These aromatic substances are very numerous ; those most frequently employed are infusions of raspberries, green walnuts, cloves, iris, and bitter almonds ; recipes for these are given below : Infusion of raspberries. Alcohol (85). An equal quantity of ripe and carefully picked raspberries. Infusion of green walnuts. Alcohol (85) 100 kilos. Green walnuts 100 Infusion of cloves. Alcohol (58) 4 litres. Bruised cloves 500 grm. Infusion of iris. Alcohol (85) 4 litres. Grated iris (Provence) 500 grm. Infusion of bitter almonds. Shells of bitter almonds 20 kilos. Alcohol (58) 40 litres. The shells should be roasted like coflee berries, and placed in the spirit while hot. These infusions ought to be made a month or two before they are required for use. The recipes of some favourite liqueur wines are as follows : Alicante. Wine of Bagnols 80 litres. Alcohol (85) 9 Syrup of raisins 10 Water .. 5 Mix well together, and add a little of the infusion of iris. WINE. 445 Cyprus. Muscatel (very old) 25 litres. White wine (dry and alcoholic) '.. 64 Alcohol (85) 5 Infusion of walnuts 1 White sugar 2 kilos. Water 1 litre. Mix the different wines together ; add the alcohol and the infusion of walnuts ; dissolve the sugar in the water, and boil till the solution becomes of a golden colour ; add it to the mixture, with a little of the infusion of cloves. Grenache. Collioure (dry) 80 litres. Syrup of raisins 12 Infusion of walnuts 1 ,, Infusion of bitter almonds 1 ,, Alcohol (85) 5 Burnt sugar (yellow) 500 gnn. Proceed as for Cyprus. Lacrymae Christi Bagnols (old) 85 litres. Gum kino 50 grm. Infusion of walnuts 1 litre. Syrup of raisins 6 ,, Alcohol (85) 8 Dissolve the gum kino in the alcohol; mix the whole together, and allow to stand. Madeira. Picardan (dry) 60 litres. Tavel (old and strong) 25 Infusion of walnuts 2 Infusion of bitter almonds 2 Sugar candy t 1*5 kilos. Brandy (58) 10 litres. Melt the sugar candy in a portion of the wine and mix the whole together. Malaga. Bagnola (old) 80 litres. Syrup of raisins 10 Infusion of walnuts 2 Alcohol (85) 8 Proceed as for Madeira. Port. Rousillon (old) 70 litres. Old Ratafia 25 Alcohol (85) 5 Mix thoroughly, and set aside for two months. Sherry. Add to the substances indicated for Madeira, from 1 to 2 litres of an infusion of white raspberries. Tokay. Baguols (very old) 80 litres. Syrup of raisins 10 Dried elder flowers 300 grm. Infusion of white raspberries 2 kilos. Infusion of walnuts 1 Alcohol (85) 6 litres. Dissolve the syrup in a little warm water ; infuse the elder flowers in it until cold ; pour the wine upon it, and agitate the whole briskly. The two most important fruity wines, viz. port and sherry, are adulterated to an enormous extent. In Portugal the juice of elderberries is largely added to port in order to heighten its colour, and extract of rhatany for the purpose of improving the colour and imparting an astringence to the wine. In England, beetroot, Brazil wood, the juices of elderberries and whortle- berries, the pressed core of elder-wine, extract of logwood, &c., are commonly added to port to give it a fictitious colour ; and oak sawdust, alum, and extract of rhatany to give it an astringent taste. A mixture of elder-juice, grape-juice, brown sugar, and crude brandy, called "jerupiga" is the commonest adulterant of port, both in this country and in Portugal ; its addition to the wine in bond is permitted by the Custom-house authorities. A mixture commonly sold for sherry consists of Cape wine, to which a nutty flavour is imparted by means of bitter almonds, and a fulness by the addition of honey, and rendered more alcoholic by a little plain spirit or pale brandy ; this mixture is subjected to an insensible fermentation, and is 446 BEVERAGES. then sold as good sherry. Sherry is coloured by means of concentrated must, burnt sugar, or spirit colouring. All the wines which have been considered above are the pure, genuine wines of the grape. Large quantities of imitation wine are manufactured, however, both in this country and in France, and it is now bought and sold to such an extent among the poorer classes that it is desirable to describe here the methods by which this inferior wine is made. Different recipes in common use for its preparation are therefore given iu full. 1. To make 150 litres, take 50 litres of wine of Kousillon, Narbonne, or St. Gilles, of three years of age, and 100 litres of the following mixture : Cold river water 85 litres. Common brandy 20 Good vinegar 1 Tartaric acid 300 grm. Powdered iris 15 to 20 Powdered wood charcoal . . . . 500 Place in a barrel the water, vinegar, and brandy ; dissolve the tartaric acid in a little of the mixture, and stir up the charcoal in it, returning the whole to the barrel and mixing well together ; beat up the whites of two eggs in a little water and add them to the mixture with constant stirring. In twelve hours' time the liquid will be clear, when it is drawn off and mixed with the wine ; in a month or two the liquor is fit for consumption, and possesses the flavour, strength, and colour of a good red wine. 2. Add to 100 kilos of unpicked grapes 100 litres of the following mixture : River or rain water 100 litres. White sugar 18 kilos. Cream of tartar (powdered) . . 300 grm. Boracicacid 60 grm. Gall nuts (well bruised).. .. 30 Common salt 100 Infuse the gall nuts for twenty-four hours in an earthenware vessel with 1 or 2 litres of boiling water. Then crush the grapes in a barrel, slightly raised from the ground and having a stop-cock. Take 25 or 30 litres of the water and heat just to boiling , dissolve in it, first the boracic acid, then the cream of tartar, and afterwards the sugar and salt, adding the solution to the remainder of the water. Pour in the infusion of gall nuts and add the whole to the crushed fruit in the barrel ; mix thoroughly by agitation. The mixture thus made begins spontaneously and almost immediately to ferment, which continues for a week or more, In order to impart a good colour to the wine, the sterna and skins of the fruit are allowed to remain in the fermenting liquor, and kept at the bottom by means of laths. The barrel is carefully covered during the process. If a deeper colour be required, it may be imparted by adding 200 or 250 grm. of dried hollyhocks before fermentation. This process complete, the wine should stand for a day or two, and may then be drawn off into a cask, when it enters at once into the secondary or insensible fermentation. 3. Another common wine is often made from the marc resulting from the process just described, which is usually rich in fermentable matter. One hundred litres of water containing the same ingredients as are mentioned in the last recipe, and also 200 grm. of dry, picked hollyhocks, are added to this marc. In less than two hours, fermentation commences, and proceeds for some days, after which the liquor attains considerable strength and a good colour. It is usually added to the wine made by the preceding recipe. Instead of the 18 kilos of sugar employed in the first recipe, 30 kilos of syrup may be used, the other ingredients remaining the same. To obtain wine of good quality and capable of long preservation, the must should indicate at least 10 by the saccharometer before fermentation. It is needless to state that the more sugar the must contains, the stronger and better will be the wine produced. 4. A very cheap wine may be made by placing in a bucket 40 or 50 litres of river water, and adding 35 to 40 kilos of raisins. Dissolve also 200 grm. of cream of tartar, and 40 grm. of boracic acid in 1 or 2 litres of boiling water, and pour the solution upon the raisins. When the fruit has swollen until the skins are almost bursting, the liquor is poured off it, and it is placed in a barrel with 100 litres of ihe mixture described under the second recipe ; the barrel is then covered over, a email outlet being left for the escape of the gas. Fermentation commences only after a day or two, and should be provoked by incessant stirring for a few hours. The wine made in this way should be clarified in a month's time with the whites of six eggs to each cask. In the bottles it is very bright and sparkling. If suffered to age in the cask it becomes dry, heady, and pleasant to the taste. 5. For another wine, either white or red, the ingredients are : White sugar 5 kilos. Raisins 5 Common salt 125 grm. Tartaric acid .. .. 200 ,. Common brandy 12 litres. River water 95 Gall nuts (bruised) 20 grm. Brewer's yeaht (in paste) . . 200 WINE. 447 Soak the raisins in a little of the water until they swell ; dissolve the tartaric acid in 2 litres of hot water ; infuse the gall nuts for twenty-four hours in 2 litres of boiling water ; then dissolve the sugar and salt in the remainder of the water, place the whole in a cask ; add first the brandy, and then the yeast beaten up in two tumblerfuls of water, and stir up briskly with a stick inserted through the bung-hole. In twelve hours' time, if fermentation has not commenced, it is provoked by renewed stirring, and then left to proceed of itself. To make this wine of a red colour, it is necessary only to add to the above ingredients 250 to 300 grm. of dry, picked hollyhocks, taking care to keep them at the bottom of the cask. Deterioration of Wines. Nearly all wines are subject to alterations of different kinds, many of them being easily prevented or cured ; some occur naturally, whilst others are accidental. Those are considered to be natural disorders which are not brought about by outside causes, such as ropiness, sourness, bitterness, and loss of colour. Accidental disorders are principally the results of frost, contact with the atmosphere, or taints derived from the cask, mouldiuesa, and bad eggs. The means employed to correct these disorders have to be modified according to the age of the wine, and to the nature and development of the alteration. When a wine becomes ropy, it loses its fluidity and becomes oily. White wines are most subject to this disorder, and especially those which have not been allowed to complete their fermentation. It occurs chiefly after a rainy season, when the wine contains but little tartar and tannin. It rarely needs special treatment, as the wine usually recovers in the course of time ; if it does not, a good cure is to add 30 grm. of pure tannin dissolved in half a litre of alcohol at 85, and to whip the mixture well. Sourness is the most common disorder of all wines ; it occurs chiefly in wines fermented in the presence of air. To avoid it, the casks destined to receive wine should always be sulphured, as has been stated already ; great care must also be taken to allow as little contact with air as possible, both during fermentation of the must and the several racking operations. It is almost impossible to permanently restore a wine which has advanced far in this malady, since it almost invariably reappears after a length of time, however much care be taken to avoid it. The best way out of the difficulty is either to mix it with a sweet wine for immediate consumption or to dispose of it to the vinegar manufacturers. Bitterness is a common disorder of aged wines and especially of Burgundy ; it is always preceded by an alteration of colour. It may be remedied by adding to each cask affected, 135 grm. of tartaric acid, or more, according to the degree of bitterness, and from 10 to 15 grm. of tannin. This treatment generally arrests the progress of the malady, and if after eight or ten days it be drawn off into a sulphured cask, clarified, and treated with 200 grm. of well-washed vegetable black, it will probably be restored to its original condition. One of the principal accidental alterations of wine is the effect of heat. Too high a temperature in the cellar is likely to excite active fermentation in the casks, which frequently results in the bursting of the latter and the entire loss of the wine. To avoid this, a quantity must be drawn from each cask, and air freely admitted, in order to check the process. Sometimes ice is introduced into the casks, or a quantity of fresh cold water for the same purpose. The most effectual remedy, however, is to submit the wine to two consecutive mckings and clarifications in a well sulphured cask, with the addition, before each racking, of from 400 to 500 grm. of powdered wood charcoal. When, in very cold weather, a portion of the wine has become frozen, it is best to draw off the liquid portion, since that which is solidified is nothing but water and may be removed without injury, the wine being rather strengthened and improved thereby. If the wine be allowed to melt again, the colour will be seriously impaired. The casks into which it is drawn must be well sulphured, and a little tartaric acid may be introduced with advantage, in order to assist in restoring the natural colour. Taints arising from mouldiness are due to the condition of the casks when filled. Wines tainted from this cause, or from the use of unsound eggs in the clarification, must never be mixed with other wines, or they will infallibly impart their disagreeable taste to the whole mixture. When so tainted, the wine should be racked off, and pieces of well-burnt wood charcoal introduced into the casks to purify it. It may then be racked again on the following day, with the addition of 500 grm. of good oil, well whipped in. It will not be fit to mix away with other wines until it has stood in the cask at least a week or ten days. Wines which have been affected with any of the disorders mentioned above, and successfully treated, should be at once disposed of for immediate consumption, since the affection is liable to return, after a lapse of time, with renewed energy. Ropiness is the only disorder which it is possible to effectually and permanently cure. Bottling. The secret of bottling wine with success consists in the exercise of much care and cleanliness. The bottles should be sound, clean, and dry, and free from the least trace of musti- ness. Experience proves that wines bottled in fine, dry weather preserve their clearness and liquidity much better than those bottled in damp weather, or in a southerly wind. The wine should be clear and brilliant, or it must be carefully fined and clarified before being finally bottled. 448 BEVEEAGES. Indeed, it is well to submit it invariably to this process previously. Care must be taken to avoid shaking the cask, and so distributing the sediment during the operation. The remaining portion which cannot be drawn off clear, should be strained through the "wine-bag" and then bottled as inferior wine. The corks should be of the best quality, and immediately before being placed in the bottles should be compressed by means of a cork-squeezer. They should also be coated with a wax, when inserted, in order to preserve the mouth of the bottle from moisture, insects, &c. A good recipe for such wax is to mix and melt together the following substances : Resinous pitch 1 kilo. I Tallow 100 grm. Burgundy,, 500 grm. | Prussian red 125 The quantity so made is sufficient to wax 300 bottles. In performing the operation, in order to avoid bursting the bottles, the mixture must be kept melted at a heat below its boiling point, and the necks of the bottles must be perfectly dry. When the process is finished, the bottles should be stored in a cool cellar, and on no account placed in an upright position, or in damp straw, but on their sides, in sweet, dry sand or sawdust. To give a wine sparkling properties, a few grains of white lump-sugar or of sugar candy may be introduced in the bottles before finally stoppering. Champagne is invariably treated in this way in France. The sugar undergoes gradual fermentation during the sojourn of the wine in the bottle, and a quantity of carbonic acid gas is thus formed and held in solution until the bottle is opened, thus affording to it the agreeable briskness and creaminess, which are so much prized in sparkling wines. Wine-production. Among the wine-producing countries of the whole world, France occupies the first place both for quantity and quality. In the year 1788, the total amount of space covered by the vine in that country was about 3,365,000 acres ; in 1829, it was estimated at 3,975,000 acres ; in 1849, at 5,482,000 acres ; in 1859, at 5,875,000 acres ; and in 1869, at 5,975,000 acres. At the present time, notwithstanding the loss of Alsace and Lorraine, the area covered by vineyards in France may be considered, in round numbers, 6,500,000 acres. These figures serve to show to what an enormous extent the cultivation of the grape has increased during the last century. The departments in the south-east of France are admirably situate, as regards climate and soil, for the production of good wine ; the produce of this region might be made equal in every respect, if not superior, to the wines of Beaujolais, Medoc, Hermitage, and Tokay. Unfortunately, however, by much the larger portion of it is rendered inferior by adulteration and mixing. The principal wines of some of these departments are the following -.fferault (red wines), Chuselan, Tavel, Saint- Genies, Lirac, Ledelon, Saint-Laurent-des-Arbres, Cante-Perdrix ; (white wines), Frontignan, Lunel, Marseillan, Pommerols, Maraussan. Pyrenees Orientates (red wines), Bagnols, Coperons, Collioure, Torsenilla, Terrats ; (white wines), Rivesaltes. Basses Pyrenees (both red and white), Juranc.on, Gan. Vaucluse (red wines), Coteau-Brule', Clos de la Berthe, Clos de Saint Patrice. Andes (both red and white), Limoux. Alpes-Maritimes Gaude, Cagnes, Saint-Laurent-du-Var, Saint-Paul, Bellet. Basses-Alpes Me'es, Manosques, Valensalles. The south-western district produces on an average 12,331,000 hectols of wine annually, and worth at the very least 406 millions of francs. The principal wines are : Gironde (red wines), Clos de Lafitte, Clos de Latour, Clos de Chateau-Margaux, Clos de Hautbrion, Clos de Eosan, Clos de Goree, Clos de Le'oville, Clos de Larose, Clos de Brane-Mouton, Clos Pichon-Longueville, Clos Calon, Pauillac, Pessac, Sainte-Estephe, Saint-Julien, Castelnau de Me'doc, Cantenac, Talence, Cotes de Canon ; (white wines), Saint-Bris, Carbonieux, Pontac, Sauternes, Barsac, Preignac, Beaumes, Langon, Ce'rons, Pujols, Hats, Landiras, Virlade, Sainte-Croix-du-Mont, Loupiac. Landes (red wines), Cap-Breton, Soustons, Messange, Vieux-Boucaud. Lot-el-Garonne (white wines), Clairac, Buzet. Dordogne(red wines), La Terrasse, Pe'chermont, Des Farcies, Campreal, Sainte-Fois-des-Vignes ; (white wines), Montbassillac, Saiut-Nessans, Sance. In the eastern district the chief wine-growing departments are the Jura, which produces the following white wines : Arbois, Chateau-Chalon, Pupillin, L'Etoile, Quintigny ; and the Drome (red wines), C6te-de-l'Hermitage, Croses, Merceurol, Gervant ; (white wines), C6te-de-rHermitage, Merceurol, Die, Vin de paille de rHermitage. In the north-eastern district, the chief departments are : Marne ( red wines), Verzy, Versenay, Mailly, Saint-Basle, Bousy, Clos Saint-Thierry ; ( white wines), Le Closet, Sillery, Ai", Mareuil, Haut- villers, Pierry, Dissy, Cramant, Avize, Oger, Le Mesnil, Epernay, Taizy, Ludes, Chigny. Saonc- et-Loire (red wines), Moulin-a-Vent, Thorins, Chenas, Fleury, Romaneche, La Chapelle Guinchet, Mercurey, Giary ; (white wines), Pouilly, Fuissey, Solutre, Chaintre. In the central and northern districts are : Cote-cTOr (red wines), La Romanee'-Conti, Chamber- tin, La Pierriere, Le Richebourg, Musigny, Clos Vougeot, La Romane'e-Saint-Vivant, La Tache, Le Clos Saint-Georges, Le Clos Premeau, Le Clos du Tart, Les Porets, La Matroie, Les Bonnes- Mares, Clos de la Roche, Clos de Beze, Clos de Saint-Jacques, Clos de Mazy, Clos de Versolles, Clos de Marjot, Clos de Saint-Jean, Vols, Nuits, Chambolle, Volnay, Pomard, Beaune, Morey, WINE. 449 Savigny, Meursault, Gevrey, Chassagne, Alx, Blagny, Santenay, Chenove. Tonne (red wines), Cotes des Olivettes, Cotes de Pytois, Cotes de Perriere, Cotes des Preaux, Cotes de la Chainette, Cotes de Migraine, Cotes de Clairion, Cotes de Boivins, Que'tard, Pied de Eat, Chopette, Judas, Rosoir, Irancy, Couliinges ; (white wines), Vaumorillon, Les Grise'es, Le Clos, Valmur, Grenouille, Bouguerau, Mont-de-Milieu, Chablis. Aube (red wines), Les Kiceys, Balnot-sur-Laigne, Avirey- Lingey, Bagneux-la-Fosse. The culture of the grape in Algeria has developed slowly during the last twenty years, and, at the present time, several excellent wines are made in that country, the soil and climate of which are particularly favourable. Some of these wines were shown in the Paris Exhibition of 1878. The vineyards of Oran, Mascara, and Tlemcen furnish fine red wines ; those of Bone and Doue'ra excellent dry white wines. Austria produces annually, on an average, 3,242,146 hectols. of wine. The Austrian territory which produces the largest quantity is Lower Austria and Dalmatia. The Tyrol, Styria, Austro- Illyria, Carniola, and Moravia come next. The northern provinces also produce wine, but it is of an inferior kind. Austrian wines are both red and white, the latter being dry. Some localities produce liqueur wines, and sparkling wines are made at Voslau, in Lower Austria and near Graz, in Styria. All these are made on thoroughly sound and good principles. The production of wine in Hungary is estimated at 2,798,520 hectols. annually. The most celebrated Hungarian wines are Tokay, Szamorodui, Szalmabor, Me'nes-Magyarat, Rust, Saint- George, Sopron, Sumlo ; these are all fruity or liqueur wines. There are also many very highly esteemed dry wines, both red and white, made in Hungary and Transylvania ; some of these are noted for their excellent bouquet. Hungarian wines are exported to Austria, Prussia, Poland, Russia, and England ; a very small quantity only is sent to France. In the Exhibition of 1878, Hungary was represented by three hundred exhibitors, with more than 860 samples of choice wine : red, white, fruity, dry, and sparkling. There is but little wine made in Switzerland, though there are a few vineyards which produce very superior wines. The red and white wines of Neufchatel are much esteemed. In the canton of Vaud, there are three good brands, namely, those of Yvorn, Lavaux, and Lacote. The canton of Valais produces what are known as " Glacier " wines ; and that of Zurich an excellent brand known as Neftenbach. Swiss wines are carefully prepared. The soil and climate of Spain are in every respect admirably adapted for the cultivation of the grape. The wine produced by this country in the year 1878 amounted to 10,510,026 hectols., which, considering the extent of the country and its remarkable advantages, is not by any means a large quantity. Spain produces wines of many different varieties. The fruity wines of Spain have been noted for centuries for their exquisite qualities of perfume and flavour : the most celebrated are the wine of Xe'res, or Sherry, Malaga, and Rota; the next in order are the wines of Mon- tilla, Valdepenas, Carinena, Peralta, and Sitges. Spain produces also some sparkling wines. Sherry, Malaga, and Montilla come chiefly from the province of Andalusia ; the two Castiles furnish the wines of Toro, Rueda, Seca, Nava del Rey, Villarubia, Ocana, Yepes, Arganda, San Martin, and the celebrated Valdepenas. Saragossa, Catalonia, Aragon, and Navarre produce many esteemed red and white wines, of which the best known are these of El Campo and Carinena. Finally, the provinces of Valencia, Murcia, Alicante, Caceres, and Badajoz furnish some very fine brands, amongst which may be mentioned those to which one of these provinces has given its name, the wines of Alicante. Spain was represented in the Exhibition of 1878 by 1536 exhibitors. Portugal enjoys the same favourable conditions of soil and climate as Spain, and like the Jatter country is justly renowned for the quality of its wines. By extending the cultivation of the grape, however, Portugal might easily double its annual production, which during the years 1874, 1875, and 1876 inclusive, amounted only to about 4,000,000 hectols. The wine-growing districts of Portugal are the following: Douro, Traz-os-Montes, Minho, Beira-Alta, Estremadura, Alemtejo, and Algarve. The average yield of the Douro is about 400,000 hectols., comprising the famous " Port," which is so largely consumed in England ; and some other wines, as those of Muscat, Malvasia, Bastardo, &c. The second district, that of Traz-os-Montes, produces about the same quantity as the Douro ; they are very light, dry, and aromatic. All the other districts produce more or less excellent wines. The Portuguese island of Madeira has been celebrated for its wines for a very long period. Of the different varieties, the finest is that known as Malmsey, which is the produce of a particular vineyard ; next in order come the wines of Tinta, t?ercial, Bual, and Bastardo. All Madeira wines increase considerably in quality and in strength by keeping. They are much esteemed in this country. The situation of Italy is highly favourable to the cultivation of the grape and the production of good wines. The annual produce is about 27,000,000 hectols., but this quantity might be very considerably increased. In 1867, the produce of the whole of Italy was 28,879,908 hectols. ; the average produce at the present time is rather less than this. The most celebrated Italian wines 2 a 450 BLACKING. are those which are furnished by the vineyards in the neighbourhood of Vesuvius, one of which is the excellent liqueur wine called Lacrymse-Christi. The wines of Piedmont, known as Barbera, Nebbiolo, Barolo, Gattinara, Malvasia d'Asti, &c., are also much esteemed. The Sicilian and Sardinian brands, 'however, constitute the most important produce of Italy. The former island is renowned for its Marsala, Malvasia, and Moscati, and for the wines called Etna-Madeira and Syracuse. There were 158 representatives of Italy at the Exhibition of 1878, and 417 samples were exhibited, each being accompanied by its analysis. Greece has long been celebrated for the excellence of its wines. The dry wines of Corinth have special qualities of bouquet and aroma. Those of the island of Thyra are considered to be superior to all other Grecian brands ; four-fifths of these are dry and acid, the remainder being very sweet red and white wines, known as Vino Santo. The island of Cyprus is celebrated for the liqueur wine to which it has given its name. Australia is fast taking a prominent place among wine-producing countries. The soil and climate of many parts are well suited to viticulture. Some of the wines are richer and more alcoholic than those of Portugal ; a few are of soft, luscious, delicate flavour, while others resemble the Sauternes. BLACKING. (FR., Cirage; GEB., Wichse, Stiefelwichse.) Blacking is a pasty compound used for producing a polish on black leather surfaces, especially on the " uppers " and the edges of the soles and heels of boots and shoes. There are numerous methods of manufacturing this substance ; but in nearly all, the base is a black colouring matter, usually animal charcoal, mixed with substances which acquire a gloss by friction, such as sugar and oil. The carbon employed should be in the form of a very deep, finely powdered black. Since it always contains carbonate and phosphate of lime, it is treated with a mineral acid in order to decompose these salts ; a mixture of sulphuric and hydrochloric acids is frequently used, the salts produced being acid phosphate of lime, sulphate and chloride of lime. The sulphate of lime gives consistence to the pasty mass, and the two other salts being deliquescent help to keep the leather flexible. No more acid should be used than is sufficient to decompose these salts, or the leather will be destroyed. It is probably to prevent this that some makers add a small quantity of alkali to the blacking. Sometimes powdered gall-nuts, sulphate of iron, indigo, and Prussian blue are incorporated with the blacking in order to impart to it a good colour. Fatty or oily matters are also sometimes added in order to preserve the flexibility of the leather, and to neutralize any excess of acid which may remain. The consistence of different blackings varies widely ; they mav be classed either as liquid or as solid blacking. The well-known liquid blacking of Day and Martin is composed in the following manner. Very finely ground animal charcoal, or bone-black, is mixed with sperm oil till the two are thoroughly commingled. Eaw sugar or treacle, mixed with a small portion of vinegar, is then added to the mass. Next a small measure of dilute sulphuric acid is introduced, which, by con- verting into sulphate a large proportion of the lime contained in the animal charcoal, thickens the mixture into the required pasty consistence. When all effervescence has subsided, but while the compound is still warm, vinegar is poured in until the mass is sufficiently thinned; then it is ready to be bottled for the market. The following are other ways of making liquid blacking : 1. Animal charcoal, 5 oz. ; treacle, 4 oz. ; sweet-oil, f oz. ; triturate until the oil is thoroughly incorporated, then stir in gradually pint each vinegar and beer lees. 2. Animal charcoal, 1 Ib. ; sperm oil, 2 oz. ; beer and vinegar, each 1 pint, or sour beer, 1 quart. 3. Bryant and James's indiarubber blacking. Indiarubber in very fine shreds, 18 oz. ; hot rapeseed oil, 9 Ib. (1 gallon) ; animal charcoal in fine powder, 60 Ib. ; treacle 45 Ib. ; gum arabic, 1 Ib., previously dissolved in vinegar, No. 24 strength, 20 gallons. The mixture is triturated in a colour-mill until perfectly smooth, then placed in a wooden vessel, and sulphuric acid added in small successive quantities amounting altogether to 12 Ib. This is stirred for half an hour daily for fourteen days, then 3 Ib. of finely ground gum arabic are added, and the stirring repeated for an additional fourteen days, when the blacking will be ready for use. 4. It has been proposed to treat the leaves and other portions of the mastic gum tree, Pistacia lentiscus, by decoction or distillation, principally to obtain from them a blacking which dries almost immediately after application, shines without the necessity of being brushed, and is much less liable to soil the clothes. 5. Acme blacking. To rectified spirit, 1 gallon, is added blue aniline, 20-80 drachms, and Bismarck brown aniline, 31 -20 drachms, the solution of the two last being effected by agitation within eight to twelve hours. After the solution is completed, the mass is allowed to settle, and the liquid portion is drawn off by spigots above the sediment, and filtered if necessary. The alcohol is placed in the apparatus first, then the colours, and the mixture agitated every hour for a space often to fifteen minutes. Of this liquid gallon is added to rectified spirit, 1 gallon, and in this are dissolved gum camphor, 11 oz.; Venice turpentine 16 oz.; gum shellac, 36 oz. To benzine, BLACKING. 451 J gallon, add castor oil, 3^ fluid oz., and boiled linseed oil, If fluid oz. The two solutions are then united by agitation, but should not be allowed to stand over two days in any vessel of iron or zinc, as in the presence of the gums the colours will be decomposed by contact with zinc in eight days, and with iron in eighteen to twenty-four days. 6. A quantity of ordinary starch is dissolved in hot water, and while still hot oil or wax is added, the mixture is stirred and allowed to cool. When cold a small quantity of iodine is added to give a bluish-black colour. To a gallon of this are added 8 oz. of a solution of perchloride or other per salt of iron, and a small quantity of gallic or tannic acid (or both), and sometimes about 2 drachms of oil of cloves with 8 oz. glycerine. The whole is thoroughly stirred. Paste blackings are also made in a variety of ways, of which the following are the chief: 1. Bryant and James's iudiarubber blacking may be made in a solid form by reducing the pro- portion of vinegar from 20 gallons to 12. The compound then only requires stirring for about six or seven days in order to prepare it for use, and it may be liquefied by subsequent addition of vinegar. 2. Dr. Artus manufactures Hacking from the following materials : Lamp-black, 3 or 4 Ib. ; animal charcoal, 5 Ib. ; are well mixed with glycerine and treacle, 5 Ib. Meanwhile guttapercha, 2 oz., is cautiously fused in an iron or copper saucepan, and to it is added olive oil, 10 oz., with continual stirring, and afterwards stearine, 1 oz. The warm mass is added to the former mixture, and then a solution 6f gum Senegal, 5 oz., in water, 1 Ib., and 1 drachm each of oil of rosemary and lavender may be added. For use it is diluted with three or four parts of water, and tends to keep the leather soft, and render it more durable. 3. All ordinary paste blackings require to be mixed with some liquid before application, causing considerable waste. It is claimed for the subjoined method of preparation, that by its means the blacking is rendered of such a condition that when merely dipped in water or other solvents the required quantity can be rubbed on to the article to be blacked without the cake crumbling or breaking up. The ingredients of the blacking are those in ordinary use, but it is brought to the required consistence by combination with Kussian tallow, in the proportion of 3 per cent,, and casting the mass into the desired forms. These may be cylindrical, &c., and may be enclosed in covers of cardboard, tinfoil, &c., in which the blacking can slide, so that when one end is pushed out for use, the remainder acts as a handle. The exposed end, when damped by immersion or otherwise, can be rubbed on the article without crumbling. The ivory-black (animal charcoal) which has been used in the preparation of white paraffin, according to Letchford and Nation's patent, may be conveniently used for making blacking. 4. The addition of sulphuric acid to animal charcoal and sugar produces sulphate of lime and a soluble acid phosphate of lime, which m;ike a tenacious paste. Thus : Animal charcoal, 8 parts; molasses, 4 parts; hydrochloric acid, 1 part; sulphuric acid, 2 parts. These are well mixed. A liquid blacking may be produced from this by the addition of the necessary proportion of water. 5. Fuller's earth, 8 oz. ; treacle, 3 Ib. ; animal charcoal, 2 Ib. ; butter scrapings, 4 oz. ; rape- seed oil, 4 oz. ; strong gum water, | pint ; powdered Prussian blue, | oz. ; commercial sulphuric acid, 8 oz. If the blacking is required in a liquid form, add \ gallon of vinegar. 6. To animal charcoal, 1 Ib., add commercial sulphuric acid, 4 oz. ; work them well together, and when the acid has done its duty upon the charcoal add fish or colza oil, 4 oz.'; stir the mixture till the oil is thoroughly incorporated, then pour in gradually a strong solution of washing soda or other suitable antacid, and continue the stirring till ebullition ceases, or the acid is neutralized. Next add about 8 oz. treacle, and then pour in a solution of gelatine and glycerine, in quantity about 2 quarts if liquid blacking is required, but less will suffice to produce paste. The solution of glycerine and gelatine is made by dissolving the best size in hot water, in the proportion of 4 purts of water to 1 of size, and then adding to every quart of the liquid 1 oz. of glycerine. The addition of the glycerine and gelatine preparation gives great brilliancy, depth of colour, and permanency to the blacking when applied to leather, and at the same time makes it damp-proof; besides which the antacid has the effect of neutralizing the sulphuric acid employed, and thus prevents the injurious action of that acid on the leather, as in the case of most ordinary blackings. For application to dress boots the following composition is prepared; Gum arabic, 8 oz. ; molasses, 2 oz. ; ink, \ pint ; vinegar, 2 oz. ; spirit of wine, 2 oz. Dissolve the gum and molasses in the ink and vinegar, strain, and then add the spirit of wine. Harness blacking is not made in the same way as boot blacking. The following are some of the methods of preparing the former kind : 1. Glue or gelatine, 4 oz. ; gum arabic, 3 oz. ; water, f pint. Dissolve by heat, and add of treacle, 7 oz. ; finely powdered animal charcoal, 5 oz. ; and then gently evaporate until the compound is of the proper consistence when cold, stirring all the time. It must be kept corked. 2. Mutton suet, 2 oz. ; beeswax, 6 oz. ; melt them, and add sugar candy, 6 oz. ; soft soap, 2 oz. ; lamp-black, 2J oz. ; finely powdered indigo, \ oz. When thoroughly intermixed add oil of tur- pentine, J pint. 2 G 2 452 BLACKS. 3. Beeswax, lib.; animal charcoal, J lb.; Prussian blue, 1 oz., ground in linseed oil, 2oz.; oil of turpentine, 3 oz. ; copal varnish, 1 oz. Mix them well, and form the mass into cakes while it is still warm. 4. Add to No. 3, while still warm, soft soap, 4 oz. ; oil of turpentine, 6 oz. ; put into pots or tins while warm. 5. Isinglass, \ oz. ; finely powdered indigo, J oz. ; soft soap, 4 oz. ; glue, 5 oz. ; logwood, 4 oz. ; vinegar, 2 pints ; ground animal charcoal, -i oz. ; beeswax, 1 oz. Infuse the logwood in the vinegar for some time with gentle heat, and when the colour is thoroughly extracted strain it, and add the other ingredients. Boil till the glue is dissolved, then store in stoneware or glass jars. Said to be very useful for army harness. 6. Melt 4 oz. mutton suet with 12 oz. beeswax, 12 oz. sugar candy, 4 oz. soft soap dissolved in water, and 2 oz. finely powdered indigo. When melted and well mixed, add J pint turpentine. Lay it on with a sponge, and polish with a brush. A good blacking for working harness, which should be cleaned and polished with it at least once a week. 7. Three sticks of black sealing wax dissolved in pint of alcohol, and applied with a sponge ; or lac dissolved in alcohol, and coloured with lamp black, answers the same purpose. This is intended for carriage harness ; it is quick drying, and hard and liable to crack the leather, so should be applied as seldom as possible. 8. A good blacking consists of: Hog's lard, 4 oz. ; neat's-foot oil, 16 oz. ; yellow wax, 4 oz. ; animal charcoal, 20 oz. ; brown sugar, 16 oz. ; water, 16 oz. Heat the whole to boiling, then stir it until it becomes cool enough for handling, and roll it into balls about 2 in. in diameter. 9. Soften 2 lb. of glue in 1 pint of water ; dissolve 2 lb. soap (Castile is the best, but dearest) in 1 pint of warm water : after the glue has become thoroughly soaked, cook it in a gluepot, and then turn it into a larger pot ; place this over a strong fire, and pour in the soap water, slowly stirring till all is well mixed ; then add \ lb. of yellow wax cut into slices ; let the mass boil till the wax melts, then add | pint of neat's-foot oil and sufficient lamp black to impart a colour ; let it boil a few minutes and it will be fit for use. 10. When harness has become soiled it can be restored by the use of the following French blacking : Stearine, 4i lb. ; turpentine, 6f lb. ; animal charcoal 3 oz. The stearine is first beaten into thin sheets with a mallet, then mixed with the turpentine, and heated in a water bath, during which time it must be stirred continually. The colouring matter is added when the mass has become thoroughly heated. It is thrown into another pot, and stirred until cool and thick ; if not stirred it will crystallize, and the parts will separate. When used it will require warming ; it should be rubbed on the leather with a cloth, using but very little at a time, and making a very thin coat. When partially dry it is rubbed with a silk cloth, and will then give a polish equal to that of newly varnished leather, without injuring it in any way. Liquid blacking is usually filled into small bottles of very coarse stoneware, closed by corks. Paste blacking is formed into cakes, which are secured in waterproofed paper, generally prepared by steeping the paper first in boiled linseed oil, and pressing, then hanging up to dry for from eighteen hours to a week. The following is an improved way of making a waterproof paper of superior quality, thinner, but equally strong, and capable of drying in less than a minute. The paper is steeped in a melted or fluid composition, consisting of paraffin, wax, or hard tallow, in combination with crude or other turpentine, in the proportions of two to one. It is then imme- diately pressed, and the surplus composition is removed by passing it between rollers heated by steam. By using paper in endless sheets, the whole process might be made continuous, the paper being finished for use or storing by the time it leaves the rollers. It is obvious that the manufacture of blacking requires neither skill nor capital. It may be conducted on almost any scale according to the demand. The chief trade is, at the present time, in the hands of one or two very large firms; but smaller makers are scattered throughout the country. Though the consumption of the article is very considerable, its price is so low that it represents a small money value. It is neither exported nor imported in any appreciable quantity. BLACKS. Several manufactured carbonaceous substances are known in commerce under the generic name of "Blacks." The most important of these are animal-black, bone-black, Frankfort-black, ivory-black, and lamp-black. They are usually obtained by carbonizing organic matter, particularly bones, in closed vessels or crucibles, or by collecting the soot formed by the combustion of oily, resinous, and bituminous substances. Other blacks than those enumerated are manufactured, but only on so small a scale as to be of no commercial importance. Animal-black. (FR., Noir animal ; GEB., Knochenschicarz.) This substance is almost identical with bone-black, but is generally in a more finely divided state. Any animal refuse matter may be used in its preparation, such as albumen, gelatine, horn shavings, &c. These are subjected to dry distillation in an earthenware retort. An inflammable gas is given off, together with much oily tiatter, ammonia, and water, while a black carbonaceous BONE-BLACK. 453 mass is left behind. This is washed with water and powdered in a mill, the product being animal- black. It is largely used in the manufacture of printing ink (see Ink), and of blacking (se e Blacking). Bone-black. (FR., 2foir cfos ; GEB., Enochenschwarz.) When bones are heated in a retort or crucible, the organic constituents are decomposed and carbonized. A mixture of combustible gases is given off, which do not condense on cooling ; and others, which condense in the form of a heavy oil, called bone-oil, and also much water containing tarry water and ammouiacal salts in solution. The residue in the retort or crucible consists of finely divided carbon in intimate mixture with the inorganic constituents of the bones : this mixture constitutes ordinary bone-black, or animal charcoal, as it is sometimes called. The inorganic portion may, if required, be removed by washing the residue in dilute hydrochloric acid. The process, as worked on the large scale, is carried on in different ways, according as it is desired to collect the volatile condensable portion of the distillate, or to allow it to escape. In the latter case, when it is required to obtain only bone-black, the apparatus employed is of a very simple nature, and the amount of fuel needed is comparatively small. The carbonization is effected in fire- clay crucibles, 16 in. high and 12 in. in diameter. These are to be preferred to crucibles made of iron, which were much used at one time, since they do not lose their round form when subjected to a high temperature ; in consequence of this, they fit more closely together in the furnace, less air can penetrate, and therefore less of the charcoal is consumed by oxidation. The furnace is an ordinary flat hearth, having a superficial area of about 40 square yards, and is covered in with a flat arch, all of brickwork. The fireplace is situate in the middle of the hearth ; the crucibles are introduced through doors in the front, which are bricked up when the furnace is filled ; each furnace holds eighteen crucibles. The crucibles, filled with the coarsely broken bones, are covered with a lid luted on with clay. To economize fuel, the furnaces should be in a row, and placed back to back. The arrangement of the furnace and pots is shown in Figs. 312 and 313. A is the fire- place; B, the crucibles, eighteen in number, spread over the floor of the furnace in a single layer ; c, d, e, and / are the flues for conducting away the heated gases arising from the calcination of the bones, as well a s the waste heat itself; the last portion of the flue is fitted with a damper g. 454 BLACKS. The furnaces are intended to be built in fours, back to back, the waste heat serving in a great measure to conduct the operation of the revivifying apparatus placed in the centre ami marked C. When the furnace is filled and the doors are bricked up, the heat is slowly raised to redness, at which point it is kept for six or eight hours. The combustible gases are evolved and consumed in the furnace as soon as the bones begin 'to decompose, and by this means so much heat is produced that only a small quantity of fuel is needed to maintain the required temperature. "When the car- bonization is complete, the doors are taken down and the crucibles removed to cool, their place being immediately filled with fresh ones. The heat must be kept as uniform as possible through- out the process : if it be not sufficiently high, the boue-black will contain a portion of undecom- posed organic matter, which renders it quite unfit for use ; if, on the other hand, the temperature be raised too high, the bone-black will become dense and compact, whereby its efficacy as a de- colorizer is much reduced. When the charcoal in the crucible has become perfectly cool, it is removed and crushed. When required for decolorizing or deodorizing purposes, it is only roughly broken up into small lumps, in which form it is most readily applicable. The crushing is effected by means of two grooved cylinders, consisting of toothed discs, alternately 10 and 12 in. in diameter. These are so placed that the 10-in. discs of one cylinder are opposite the 12-iu. discs of the other, and thus, in revolving, the carbonized bones are crushed to fragments between them, but are not reduced to powder. They are passed successively through six of these mills, the cylinders of each couple being nearer to each other than the last. Finally, the crushed bones are carefully sieved ; the powder is placed apart from the lumps, again passed through finer sieves, and sorted out into different sizes. A furnace such as that described above will carbonize four charges of bones in one day, each charge being more than half a ton in weight. With careful work, the bones will yield 60 per cent, of bone-black, or more than one ton daily. If it be required to condense the volatile gaseous products of the carbonization, this process is conducted in retorts similar to those used in the manufacture of acetic acid from wood : these are so arranged that the whole of the gaseous products are condensed and collected. The aqueous portion of the distillate is usually evaporated down to obtain salts of ammonia ; the uncon- densable gases may be employed for illuminating purposes. The manufacture of bone-black is usually carried on in the neighbourhood of large towns, where a good supply of bones may be readily obtained. The principal use of bone-black, or animal charcoal, is to decolorize various solutions, parti- cularly syrups ; inferior qualities are used in the manufacture of blacking. The decolorizing pro- perties of this substance are extensively made use of by sugar refiners in the purification of their different syrups (see Sugar). When it has become unfit for the clarification of the sugar liquors, the charcoal is purified for re-use by processes which will be described in the article on Sugar. Ordinary bone-black has about the following composition : Phosphate and carbonate of lime, and sulphide or oxide of iron, 88 parts ; chareoal, containing a small quantity of nitrogenous matter, 10 parts; silicated carbide of iron, 2 parts. The decolorizing properties of bone-black are due solely to the presence of the charcoal. When intended for use as a deodorizer or decolorizer, bone-black should be kept carefully ex- cluded from the air, for by exposure it loses this power to a great extent, and becomes almost inert. That which has been freshly burnt is therefore best for these purposes. The cost of production of bone-black may be calculated as follows : *. d. | s- *. 4 tons fat bones at 4s. per Breaking up the bones . . . . 154 wt 1600 Rent and taxes 080 27 bushels coal 139 ; Interest, repairs, and wear and 2 firemen 049 I tear 072 4 workmen 080 i Contingencies and transports . . 024 1 carman 024 2horse 8 5 7 I i20 7 3 Produce : Black, 60 per cent., say 38 cwt. in grains, at 14s. 3d 13 10 9 10 cwt fine, at 5s. 6d. 178 Fat, 6 per cent, say 5 cwt., at 31s. 8d. 7 18 4 22 16 9 22 16 9 Profit 296 Frankfort-black. (Fa., Noir de Francfort ; GEE., Frankfurter Schicarz) Frankfort-black is a black powder obtained from dried vine-twigs, carbonized to a full black and then ground very fine. On a large scale, it is prepared from a mixture of vine-twigs, win eg LAMP-BLACK. 455 lees, peach stones, bone shavings, and ivory refuse. It varies in shade according as the animal or vegetable charcoal is in excess ; when the latter predominates, the powder is of a bluish colour ; but when there is an excess of animal charcoal, it has a brownish tinge. It is customary to wash the powder well when first made, in order to remove any soluble inorganic impurities. The finest Frankfort-black is probably the soot obtained from the combustion of the materials mentioned above. It makes an excellent pigment, and is extensively used by copperplate engravers in the preparation of their ink. Ivory-black. (Fs., Noir cCIvoire ; GEE., Elfenbein-Schwarz.) Ivory-black is a beautiful black pigment prepared by carbonizing waste fragments and turnings of ivory. These are exposed to a red heat for some hours in crucibles, great care being taken to avoid overheating or burning. When quite cold, the crucibles are opened, and the contents pulverized, the richest coloured fragments being kept apart for the best quality. The powder is then levigated on a porphyry slab, washed well with hot water on a filter, and dried in an oven. The product is of a very beautiful velvety black colour, superior even to that obtained from peach kernels, and quite free from the reddish tinge which so often characterizes bone-bluck. Ivory-black, like Frankfort-black, is employed by copperplate printers in the preparation of their ink. Mixed with white lead, it affords a rich pearl-grey pigment. Lamp-black. (Fu., Noir de Fumee; GER., Kienruss.) Lamp-black is an exceedingly light, dull-black powder, formed by the imperfect combustion of oils, fats, resins, &c. It may be prepared on a small scale by suspending a small tin-plate funnel over the flame of a lamp fed with oil, tallow, or crude naphtha, the wick being so arranged that it shall burn with a large and smoky flame. Dense masses of this light carbonaceous matter gradually collect in the funnel, and may be removed from time to time. The funnel should be furnished with a metal tube to convey the gases away from the room, but no 3U - solder must be used in making the con- nections. An especially fine quality of lamp- black is obtained from bone-oil, deprived of the ammonia with which it is always contaminated. It is manufac- tured on a commercial scale by means of the apparatus shown in Figs. 314 and 315. The oil is contained in the lamp A and kept at a constant level by means of the globular vessel B, which is also filled with oil and inverted over A. The oil flows from the lamp into the tube C, which is bent upwards at the further extremity on a level with the oil in the lamp. A cotton wick is supplied to the bent end of the tube, as we'll as , a little spout D, for conducting away any oil that may overflow into the receptacle E placed beneath. A conical hood surrounds the flame of the lamp and terminates in a tube 6, through which are conveyed the sooty products of the combustion of the oil into the wide lateral tube c, arranged to accommodate the smoke from about a dozen such lamps placed 315. at intervals of about 6 ft., as indicated in the figures. The effect of this wide tube c is not only to cool the smoke but also to collect the water and other liquids condensed. The smoke and vapours pass hence into d, the first of a series of sacks made of closely woven linen, about 10 or 12 ft. long and 3 ft. in diameter, closed at the bottom with a trap or slide e, and formed at the upper and lower ends of sheet-copper tubing made funnel-shaped. The upper one of these is prolonged into an additional pipe /, by means of which the smoke arrives at the second sack g in the series, thence finding its way to the third, and so on till the last sack of the row is reached. In connection with the last sack of each row is placed a horizontal flue F, in which are arranged frames covered with wire gauze and mounted on hinges - ' Their purpose is to retain the small remaining portions of lamp-black passing out with the smok e from the sacks. The meshes of the gauze are constantly getting filled up with soot, which --&<) 456 BLEACHING POWDER. necessitates a periodical checking of the draught for its removal. This is done by means of the rod G, which, when raised and allowed to fall suddenly, jerks the accumulated mass off the gauze. The current of air passing through the entire apparatus can be regulated by a damper placed at the entrance to the chimney in which the flue F embouches. At regular intervals, the mouthpieces in the lower ends of the sacks are removed, and their contents are shaken out separately and collected according to their various qualities. That gathered from the first sack in each row should always be kept apart from the remainder, as it is much contaminated by the presence of resinous and tarry matters. A process has been devised by Messrs. Martin and Grafton for the preparation of lamp- black from coal-tar, which affords a very good product. The coal-tar is first stirred up ener- getically with lime-water in any convenient vessel, after which the mixture is allowed to stand until the coal-tar has subsided to the bottom, when the lime-water is drawn off. The tar is then well washed by dicantation with hot water, and rectified in the ordinary naphtha still. Afterwards it is run into a long iron cylinder, which is placed over a furnace, and supplied with numerous large burners. Each burner has a metal funnel placed immediately above it, connected with a cast-iron pipe, into which all the fumes from each burner are conducted. The naphtha in the cylinder is heated almost to the boiling point by the furnace beneath. A series of smaller pipes lead away the fumes from the main pipe into a row of chambers, and thence into a series of large canvas bags, placed side by side, and connected alternately at top and bottom. The bags vary in number from fifty to eighty, the last one being left open to allow the smoke to escape, after tra- versing some 400 yards since leaving the burners. The best quality of lamp-black is found in the last bags, that near the furnace being much coarser and less pure. The bags are emptied when- ever they contain a sufficient quantity. The process employed in Germany for the manufacture of lamp-black is to conduct the products of the combustion of any resinous matter in a furnace into a long flue, at the end of which is pi iced a loose hood, made of some woollen material, and suspended by a rope and pulley. The lamp-black collects in this hood, and when a sufficient quantity has accumulated is shaken down and removed. In this manner about 6 cwt. of lamp-black may be collected in twenty-four hours. In England, an inferior variety is sometimes obtained from the flues of coke-ovens. That known as Russian Lamp-black is made by burning chips of resinous deal or pine wood, and collecting the soot formed ; but it is objectionable, owing to its liability to take fire spontaneously when left for a long time moistened witli oil. The lamp-black made in these ways is generally purified by calcination, in order to remove the empyreumaticoils which it invariably contains. This is effected in close vessels, and the product is called burnt lamp-black, and is especially useful as a water-colour. The particular virtue of lamp- black as a pigment lies in its state of extremely fine division, which could not possibly be attained by artificial means ; this quality renders it invaluable as the basis of black pigments, all of which contain it in a greater or less quantity. Indian ink and printers' ink are also composed principally of this substance. The transport of lamp-black is effected in barrels or bags ; when in the latter, these should be previously soaked in water containing some clay in suspension, which stops up the pores of the sacking, and thereby prevents loss. BLEACHING- POWDER. (FR., Chlorure ; GEB., Chlorkalk, Bleichpulver.') Synonym, chloride of lime ; formula, CaCl 2 O 2 + CaCl 2 . The exact nature of bleaching powder remains still a matter of doubt. It is sometimes regarded as a simple compound of chlorine with lime whence its name sometimes as an oxychloride of calcium, sometimes as a mechanical mixture, or as an absolute compound of oxychloride and hypochlorite of lime. For the various discussions upon this part of the subject, the scientific reader is referred to the writings of Millon, Fresenius, Kolb, Crace-Calvert, Schor- leminer, and a host of others. Bleaching powder, as ordinarily manufactured, is a dull white powdery substance, often agglomerated into small round lumps readily friable between the fingers. It always contains a certain amount of free chlorine, which imparts a strong pungent odour, rather agreeable than otherwise, unless too powerful. A small percentage of moisture usually present keeps it feathery, and it readily absorbs a further amount of water when exposed to the influence of the atmosphere, finally turning into a dirty white paste. Under the influence of strong light especially sunshine decomposition takes place, with the formation of chlorate of calcium. The bleaching property of the compound is owing to the presence of chlorine, the most powerful bleaching agent known. The available amount of this gas contained in a sample of ordinary bleaching powder is about 36 per cent. Beyond this about 4 per cent, goes to form chloride and chlorate of calcium. Of the 36 per cent , probably 4 per cent, as a rule is free and disengaged during the various manipula- BLEACHING POWDEB 457 317. tions preceding the actual bleaching process. For this reason, it used to be customary to sell a 32 per cent, bleaching powder, and probably an article of this constitution would be as good for the consumer, and in every way better for the manufacturer, than the bleaching powder usually put upon the market. In the endeavour to secure a high strength, both loss and damage is caused, by the disengagement of free chlorine gas and the prolonged process of manufacture. The art of bleaching is of very great antiquity, and until a comparatively recent date consisted of alternate treatments of the substance operated upon by various alkaline washings and exposure to the action of the sun and air. In this way, the oxygen of the air formed some combination with the colouring matter which could be extracted by water or an alkaline liquor. The use of chlorine was first suggested by Berthollet in 1785, and within a few years afterwards the process was worked upon a considerable scale in Scotland. The gas was generated in a glass or wooden appa- ratus by heating a mixture of salt, peroxide of manganese, and sulphuric acid, and passed into water. When a saturated solution was obtained, it was removed, and the goods bleached by being immersed in it and thoroughly boiled. The glass or wooden vessels speedily gave way to an apparatus constructed of strong sheet lead, encased in a metal jacket, with an agitator to effect a perfect mixture of the ingredients. Heat was applied by an underneath fire, or by a steam pipe introduced between the lead and the outer shell. This improved apparatus was used extensively for something like fifty years, an ordinary charge consisting of 120 parts of manganese to 150 of salt, and 185 of strong sulphuric acid. The chlorine gas was taken off by lutes and pipes in a manner very similar to that to be presently described. The addition of an alkali to the water at first caustic potash was made about 1792, and, in 1798, Charles Tennant, of Glasgow, patented the use of lime, to be employed as lime water. In this way, the article known as " bleaching liquor," still manufactured occasionally for paper- makers, was obtained. In 1799. the absorption of chlorine by dry lime was patented, and the commercial article now known as " bleaching powder " introduced. The process of manufacture, as at present carried on, is as follows : Instead of mixing together the salt, manganese, and sulphuric acid, the liquid hydrochloric acid obtained by condens- ing the gases from the sulphate of soda process, in the manner fully set forth in a previous article (see Soda), is employed, and run upon a known weight of peroxide of manganese contained in a " still." The best form of still is shown in Figs. 316, 317, and 318, and will be readily understood. The bottom consists of one slab of stone (good free-stone, or, better still, " Yorkshire flag "), not less than 1 in. in thickness. Into it are set sides of similar material, about 6 in. thick. The grooves into which the sides are let are about 1 in. in depth, and a very little wider than the side, so as to allow of " stemming." At the four corners, a, 6, c, d, Fig. 317, a diamond is cut and thoroughly stemmed with dry fire- clay, fireclay just moistened with tar and heated, red lead and glass, or any other suitable com- pound. Sometimes the indiarubber rods described when speaking of hydrochloric acid condensers are used, but this construction id apt to be faulty. The whole still is securely bound together with 1 in. iron rods, which pass through the ends, and are screwed up against upright pieces of wood, Fig. 317. The cover of the still is formed of three stones, bedded in a mixture of tar and china clay. In it are various openings a square manhole in the centre, through which the charge of man- ganese is also introduced, and round holes, to admit of steam column, acid, gas, and " dip " lutes. A false bottom technically "tables" is formed about 9 in. from the bottom stone, with stout slabs, about 12 in. wide and 5 in. thick, roughly dressed and resting upon stone or brick supports, running along the sides of the still, Fig. 316. Steam is introduced through a small iron pipe, protected from the action of the acid and gas by the stoneware column shown in Figs. 319, 320, and 321. This is set at the back of the still, and has an opening only underneath the tables. The hydrochloric acid is run in through the lute shown in Fig. 322, let into the cover near the steam column, while the " dip lute," shown in Fig. 323, likewise set in the cover, allows the workman from time to time to gauge the amount of acid he is running in. The stills are built in a range, and incline about 1 in. towards a gutter C 458 BLEACHING POWDER. along the front, which conveys away the waste liquors, &c. A good size of still is 9 ft. by 6 ft. by 4 ft. 6 in. deep, the cost, complete, being about 1007. A charge of manganese, about 6 cwt., is thrown into the still, and roughly spread upon the tables. The door is then replaced, and made tight with any convenient method of plastering, and the still is connected by the gas lute with the bleaching-powder chamber. Hydrochloric acid, of not less than 18 Twaddell, is then run in from the stock cistern, until the manganese is just covered. After beiug allowed to stand for a short time, good " strong " steam is introduced, at a boiler pressure of 45 lb., and kept at full blast for a quarter of an hour. A rapid disengagement of chlorine takes place, the gas passing away to the chambers, and a mixture of free hydrochloric acid, chloride of iron, and chloride of manganese is left in the still. Successive blasts of steam are pressed into this mixture from time to time until the operation is complete. The " bend " of the gas lute is then removed, and the contents of the still raked out, through a small opening in frout, into the gutter. The reaction occurring is represented by the following equation : Mn0 2 + 4HC1 = MnCl 2 + 2H.O -f C1 2 . For this first part of the process the generation of chlorine various manganese ores are used. The best comes from Devonshire. It is soft, and therefore easily dissolved by the hydrochloric acid, and contains up to 72 per cent, of binoxide. The Spanish ores are of like strength, and. sometimes as soft, but are more irregular in quality than the Devonshire. The German ores, as a rule, are weaker and smaller, 60 to 62 per cent., and often in a very finely divided state. Up to about 1857, the German qualities were chiefly used. The Spanish has now taken the lead. The following table gives the approximate composition of the various ores referred to : Devonshire. Spanish German lumpy. Manganese peroxide Iron oxide Carbonate of lime Silica 70-00 11-00 0-25 15-00 72-00 15-00 0"25 10-25 69-00 14-00 1-50 13-00 Alumina Moisture 1-50 2-00 50 2-00 1-50 1-25 99-75 100-00 100-25 Other descriptions occasionally used are imported from Virginia, California, and New Zealand. The Virginian is very irregular in quality. The best descriptions are very good, soft, and satis- factory in the working ; the majority of the cargoes brought over, however, are hard, and contain a good deal of carbonate of lime. Hence they not only dissolve slowly, but waste hydrochloric acid. The Californian, as a rule, is very hard. The New Zealand is of recent introduction, and is well reported of. All these varieties come up to 70 per cent. usually over. The price of a good 70 per cent ore is, at the present time, about 85s. per ton. Six years ago, it was 140s., but the introduction of Weldon's recovery process has largely decreased the consumption. 324. The hydrochloric acid should not be too weak, in order that the manganese may be more thoroughly decomposed, and the still liquors kept as strong as possible. For this latter reason, the steam should also be as free from water as possible. With all precautions, a large loss results from undecomposed manganese. To make it as small as possible, constant supervision should be kept over the working of the stills. They should never be run off until perfectly " spent," and should be kept carefully clean by a thorough raking out before a fresh charge of manganese is in- troduced. An efficient and economical form of still gutter is shown in Fig. 324. It will be noticed that the main body is formed of one balk of timber, to which are added sides of smaller pieces. This BLEACHING POWDER. 459 method of construction gives a gutter as good as if hollowed out of one large balk, costs of course much less, and can be made of a larger size than is readily practicable with one solid piece. The next operation consists in bringing the chlorine gas into contact with the slaked lime in the chambers, or " boxes." Various materials and forms of construction of chamber have been from time to time adopted wood, brick, stone, and sheet lead. The latter is now almost invariably used ; but the old stone and brick boxes are still occasionally met with. When built of stone, the chamber is only about 10 ft. square by 6 ft. high, the best material being "hard flag, and the method of con- struction somewhat similar to that of a manganese still. Sometimes a stone chamber has a lead top. A brick chamber is usually built in the shape of a long lime kiln one great arch, about 9 ft. wide and 7 ft. high. The first leaden chambers were only small packing about 2| tons of bleaching powder each. The size has been gradually increased until the chamber of most modern and improved construction is about 60 ft. long by 30 or 35 ft. wide, and packs up to 12 tons of bleaching powder. The mode of erection is shown in Figs. 325 and 326. A wooden framework is first set up, of the size of the proposed chamber, consisting of 6 in. sq. corner posts, with atout uprights, about 7 ft. apart, of 7 in. by 3 in. deals, and the top or " crown " of 7 in. by 4 in. deals. Upon this framework, is hung a casing of 6 Ib. sheet lead, the whole being burned by upright seams into one solid piece, and secured to the " crown " and uprights by straps of lead burned upon the sheet. The top is formed of similar sheets of lead burned together and strapped to joists, 11 in. by 3 in., set 14 in. apart. Two or three doorways are cut in the sides, and upon the top are formed two manholes whence also samples can be drawn and gas communication pipes. The doorways are about 5 ft. high and 4 ft. 6 in. wide, and are closed by stout sheet-iron doors swinging upon hinges and secured by cross beams and wedges. The workmanship must be of careful description to prevent any escape of chlorine. The height of a bleaching-powder chamber varies with the individual experiences of the manufacturers, but it should not average more than 7 ft. A slope of 12 in. from 7 ft. 6 in. to 6 ft. 6 in. is given to the top to prevent any accumulation of water. Various methods are adopted for connecting the side sheets with the bottom of the chamber and preventing any injury by the manipulation of the lime with shovels, &c. The best construction is shown in Fig. 327. An inner lining of lead, or skirting, 12 or 15 in. in height, is burned upon the sides and flanged 2 or 3 in. upon the ground or flooring. Over thia flange, the bottom, formed of concrete or flags, is laid. A perfectly tight joint is thereby made, and if by any mischance the lead lining is cut, the gas has still no chance of penetrating the outer sheet. The older plan is to form a skirting of 1-in. deals round the chamber. The gas from the still is carried for a short distance along earthenware pipes, on account of the heat and softening power of the steam. It is afterwards con- veyed to the chamber in lead pipes of from 3 in. to 10 in. in diameter, depending upon the number of " mains " employed. Sometimes three or four stills are connected together ; some- times a whole range of stills plays into one large main pipe. By the former plan separated mains, a more perfect command is obtained over the quality of gas served to the chamber ; but the cost of repairs and the waste of gas are greater than when only one or two mains are used, and the strong and weak gases pass on to the lime indiscriminately. In any case the pipes from the stills must have a considerable fall, so as to keep all condensed steam out of the chambers, and allow it a free course back into the still. The best method of connecting the gas mains with the pipes leading finally to the individual chambers is shown in Fig. 328, and consists of two water lutes and a movable bend, or " elbow." The small vertical pipe is to carry off into any suitable cistern or drain the last products of condensation. The lime employed is of two kinds French " cliff," obtained from the banks of the Seine, and Bomewhat akin to the Dover chalk cliffs, and the pure limestone found in various parts of England 460 BLEACHING POWDER. and Ireland, more particularly in Derbyshire and the neighbourhood of Belfast. Cliff varies considerably in its composition, from pure limestone to impure " chalk." Some English descrip- tions of the latter have indeed been often worked tip into bleaching powder, the temptation being the lowness of cost ,- 'but in the long run, the operation does not pay, owing to the exceedingly uncertain composition of the chalk. Good limestone the lumps that are usually burned for bleaching powder has about the following composition : Carbonate of lime Phosphate of lime 98-25 0-50 trace trace Silica Iron and alumina 0-50 0-40 99-65 The stone is thoroughly calcined in any convenient form of kiln, care being taken to reject all portions not completely burned, and then slaked with water. This slaking requires considerable care and experience. Only a very slight excess of water should be used. If too great, a pasty mass is formed which resists the action of the chlorine ; if, however, the whole is not thoroughly slaked, the absorption of the gas is incomplete, and raw lime goes through into the bleaching powder. The plan usually adopted is to spread the lumps of calcined stone in a layer about 12 in. deep, and to add the water through a rose pipe until the pieces fall into a fine powder. The portions of unburnt lime can be readily discovered and thrown out during the slaking process. The lime is next passed through a sieve of about sixteen meshes to the inch, and is spread upon the floor of the bleaching-powder chamber to a depth of about 8 in., the surface being slightly furrowed. If the depth of lime is too great, it is impossible to bring the chamber up to strength without frequent turnings, and consequent loss of gas. When the charging is completed, the manhole doors are luted on, the sheet-iron doors wedged up, and plastered round with lime or loam. The chlorine gas is now admitted from the still*, and the chamber " pressed " until a sample drawn from the top shows about 22 per cent, of chlorine. The gas is then turned on to another chamber, and the accumulated gas in the first box allowed to be thoroughly absorbed by the lime. When the green colour in the chamber has subsided, the doors are opened, and the charge is carefully and systematically turned over. The gassing operation is then repeated, occasionally a second turning is resorted to, and when a sample tests 37 per cent., the supply of chlorine is finally turned off, and the chamber is left to stand for six or seven hours. The doors are then opened, the manholes are removed, and the finished bleaching powder is packed into casks. Instead of allowing the unabsorbed chlorine to escape into the air when a chamber is opened, and to save the time necessary for the slow final absorption, it is very usual to have a communication with a freshly charged chamber, or a small antechamber, into which the gas is drawn when the bleach is finished, or when the box requires "turning." Various precautions should be observed in gassing the lime. A due proportion of " maiden " i. e. pure chlorine, and " spent " gas gas mixed with steam should be used. If the weak gas be brought into contact with the lime in too great a proportion especially with fresh lime, a coating will be formed upon the sur- face, which resists the penetration of the chlorine. If a chamber be too rapidly pressed, a large pro- portion of the chlorine will remain in the powder only mechanically held, and will fly off when the bleach is packed. The common belief that the temperature of a chamber should not exceed about 80 or 90 F., while right in practice is probably wrong in theory, the mischief of a higher temperature arising not from the actual heat of combination, but from the presence of steam, of which the tem- perature is an indicator. Perhaps the best admixture of strong and weak gas is obtained by passing fie product of a large number of stills into one main. The more usual plan is to have separate mains for about every three stills, and, with careful management, the gassing of a chamber can be more perfectly regulated by this method. The loss of chlorine during the operation of packing is about 0'75 per cent. When packed, the loss is at the rate of about 1 per cent, per month in hot weather, and 5 per cent, in cold. Instead of building the bleaching- powder chambers upon the ground, after the manner shown in Pig. 329, a very usual and excellent plan is to arrange them at a considerable elevation, upon suitable supports, to form a warehouse below. The packing is then performed by raking the bleaching powder into wooden spouts, countersunk in the floor, from which it falls into casks placed beneath. A closed connection between spout and cask is BLEACHING POWDER. 461 made by sheet indiarubber. This method of packing is less laborious and hurtful to the men employed ; it is more quickly performed, and, although a seemingly greater loss of chlorine is appa- rent between the test in the chamber and the test in the cask, the bleach is more stable afterwards, the free chlorine being well shaken out of it by tumbling down the spout. The usual bleach cask holds from 5 to 7 cwt. The powder should be packed as tightly aa possible, both to preserve the quality and to economize the cost of casks. Owing to the disagreeable nature of the operation, this is a point which requires constant care and supervision on the part of the manufacturer. The variations of the actual process of bleaching-powder manufacture are very few. The only important one has already been noticed the preparation of liquor, by passing chlorine gas into lime water. Bleaching liquor is more esteemed upon the Continent than in this country, and is usually prepared by the bleachers themselves. The use of chalk, or carbonate of lime, has been proposed in place of the hydrate. The question of yields is an important one, as there are many loopholes for loss. Upon an average, and in round figures, 13 cwt. of good 70 per cent, manganese ore, or 17 cwt. of 60 per cent., should yield 1 ton of bleaching powder. These figures refer of course to cases where the manganese is not recovered by Weldon's cr some other process. A very great loss is incurred by the more finely divided portions of the ore being swept away with the waste liquors from the still, untouched by the acid. Further loss is sustained by the ore getting coated over, the acid being thereby prevented from penetrating to the centre. Sometimes an arrangement of washing and settling pits is made, and the waste manganese is restored to the still with a fresh charge ; but it is doubtful if the result pays for the expense and trouble. One ton of lime makes about If ton of bleach ; but the quality varies considerably with tlie quality of limestone employed. About 2 tons of stone, or cliff, go to 1 ton of calcined lime. An experienced manufacturer can readily tell, from the appearance of the lime in the kiln when the fire has burned low, when the calcining operation is completed ; and from the feeling and texture of the bleaching powder in the chamber, when the absorption of chlorine has been sufficient. The chief uses of bleaching powder are, as its name denotes, for various bleaching processes, for the raising of metallic colours, and steam blues, and for the discharging of Turkey reds in calico printing. It is also used, but to a smaller extent, as a disinfectant. Its use in the latter capacity has been somewhat circumscribed of late years by the introduction of various other substances, such as carbolic acid, &c. It is, however, one of the best agents that can be employed for this pur- pose, a great merit being its harmlessness the safety with which it can be handled and treated. The chief seats of the industry in this country are the districts of the Tyne, Lancashire, and Glasgow ; the total output is about 70,000 tons per annum. The price fluctuates constantly and rapidly. In 1805, it was about 115?. a ton. From this point, with an increased output and better methods of manufacture, it gradually declined, until, in 1866, it ruled about 111. a ton. Since then.it has risen to 111., fallen again to 5/., recovered to 9/., and, at the present time, remains steady at 5/. The cost price, when the recovery of the manganese is carefully carried out by Weldon's process to be pre- sently described, is about 4/. 15s. a ton. Under the old process it is fully 6/. a ton. Of course this variation in selling price by no means represents variation in profit. Owing to the different methods from time to time adopted in manufacturing sulphuric acid, it is difficult to give any reliable indication of the varying cost of this material ; but the following table shows the approxi- mate values of salt, since the commencement of the present century : Year. Cost of Salt per Ton, delivered at Newcastle. Year. Cost of Salt per Ton, delivered at Newcastle. t. d. s. d. 1800 14 1835 100 1801 12 1840 1 1804 11 1845 17 1810 17 1850 17 1814 10 1855 16 1818 500 1860 16 1820 1 15 1865 15 1825 200 1870 13 6 1830 100 1875 15 6 It remains to notice the most important of the many processes devised for the recovery of* the manganese, and for avoiding the use of manganese altogether. The consideration of these points has been reserved because the actual manufacture of the bleaching powder the action upon lime with chlorine gas is in all cases the same. It will be at once apparent from the details given above, and from the chemical reaction in the stills Mn0 2 + 4HC1 = Mn01 2 + 2H 2 O + C1 2 . that the manganese is only an agent in decom- posing the hydrochloric acid, issuing from the still, when its work is done, in the form of chloride of 462 BLEACHING POWDER. manganese, mixed with chloride of iron and free hydrochloric acid, and running off to waste. In addition to the expense entailed by so clumsy a process, the immense volumes of " still liquor," when run from the various works, forms a serious item in river pollution, and a nuisance to the surrounding neighbourhood. Of the processes of " regeneration " from time to time devised and carried out, those ef Dunlop and Weldon alone deserve special mention. The former was first worked about 1855 at Messrs. Tennant's, St. Rollox Works ; it consists in treating the still liquor with carbonate of lime, and decomposing the carbonate of manganese thus obtained by the simple action of heat. The liquors are first neutralized and allowed to settle, clear solution of chloride of manganese remaining supernatant. This is carefully drawn off, and run into a large boiler fitted with a shaft and agitator. Here it is mixed with ground chalk, or milk of chalk ; steam is introduced under a pressure of about three atmospheres, and the whole is kept in constant agitation for three or four hours. The following reaction takes place : MnCl 2 + CaC0 3 = MuCO 3 + CaCl 2 . When the operation is complete, the contents of the boiler are left to settle, the clear super* natant chloride of calcium is run off, and the precipitated carbonate of manganese is drained and washed to remove all chloride of calcium. The expulsion of the carbonic acid and the oxidation of the manganese are effected in a long oven about 50 ft. in length, 12 ft. wide, and 9 ft. high. Four lines of rails traverse the sole of the chamber ; heat is applied underneath by means of a flue passing down the centre, and returning on both sides. The carbonate of manganese is thrown loosely into sheet-iron wagons, which are slowly drawn backwards and forwards until the four lines of rails are traversed, the contents being subjected for something like forty-eight hours to a constant temperature of about 300 (572 F.). The water and carbonic acid are completely driven off by this process, and the residual manganese is converted by the action of the air which is allowed to circulate through the oven pretty freely, through the loosely closed doors into a mixture of peroxide and protoxide. Mr. Mactear reports well of this process, but it has not been worked on any large scale except at the St. Rollox Works. The expense of the plant is the chief objection. Some attempt has been made to utilize the chlorine lost in the chloride of calcium by substituting carbonate of magnesia for carbonate of lime, and obtaining hydrochloric acid from the resulting chloride of magnesium ; but this refinement of Dunlop's process has not been found practicable. The second, and by far the most important, of the processes set on foot for the regeneration of the manganese, is that of Mr. Walter Weldon, which consists in the precipitation of the manganese as protoxide, and in peroxidation by an injection of air in the presence of an excess of lime. This improved form of an old patent has almost revolutionized the bleach and manganese trades. The old patents that dealt with this simplest of all the methods of regeneration, failed by em- ploying only an equivalent proportion of lime, whereby only one-half of the manganese can be obtained as peroxide. Weldon's improvement consists in the addition of a sli 2 fast to the spindle and slot in the crank. This slot is made at its bottom or on its edge as at a; 2 , whereby, in the swinging of the crank w 2 , and by the action of the spring, the centerer D' is raised and lowered as required. A stop lever t/ 2 , acting against a fixed guide 2 , and fast on the spindle o 2 , limits and directs the movements of the centerer. The apparatus for feeding and passing the wire to and through the perforations m' in the nut s and inner plunger Q are as follows : E' (Fig. 398) is a reel having the wire b wound upon it, and hung to revolve freely under the draft of the wire from it. F' is the frame of the wiring apparatus (Fig. 403) hung to rock on trunnions a 3 , projecting from a ring b 3 arranged to loosely surround the shaft. The front portion of the frame is forked at c 3 , and rests on shoulders formed in the outer plunger P, being retained there by the action of a spring, except towards the completion of the down-stroke of the plungers P Q, or after they have moved a certain distance in common, and during a portion of their ascent, when the frame rests upon a fixed stop, e' (Fig. 396). The object of causing the wiring apparatus to rest by its frame on the plunger P, during the early portion of the descent of the latter in common with the inner plunger Q (which support also occurs during the completion of the up stroke of the outer plunger), is to ensure the entry of the wire 6 through the perforations m' in the nut s and inner plunger Q, and to avoid stoppage of the plungers when threading or passing the wires through the perforations. The wire b is taken from the reel E' and passed through an oiler /* on the frame F' (Fig. 403), and thence through straightening eyes or cups <7 3 , and through a feeding clamp h 3 , and eyes or guides t 3 , on a slide G', which has a reciprocating motion along the frame F', and is guided by slots r 3 . From this slide G', the wire b is passed through a clamp 1 3 on the frame F', through an anvil or cutting block m 3 , and through a front eye or guide n 3 , which is in line with the perforations m' in the nut s, where the fork c 3 of the frame F' rests on the shoulders of the outer plunger P. The feed of the wire is established by the forward movement of the slide G' by the clamp A 3 till the slide is arrested by a stop o 3 , which determines the length of the wire to be cut off after its projection by the feed through the per- forations m' in the nut s and inner plunger Q. A spring p 3 (Fig. 397) eifects the forward or feeding stroke of the slide G', and a cam q 3 on the shaft, its back movement ; H' is a cutting lever for severing the wire into successive pieces of the requisite length from the forward portion as it is projected through the nut s and outer plunger P ; it is worked respectively by a cam r on the shaft C, and by a spring s. The clamp I 3 serves to hold on to the wire b after each cut, and during the back movement of the feeding clamp A 3 , to keep up the supply. The clamps A 3 and / 3 alternately grip the wire, the former gripping when feeding, but relaxing when retiring, and the latter vice versa. More recently, an additional improvement has been made in the apparatus for feeding bristles to the machine. To provide for filling the comb with bristles, it is taken out of the machine, and 652 BRUSHES. there being duplicate combe, empty ones can be filled while the machine is at work, so that it can run without intermission. The novel filling arrangement shown in the accompanying figures enables one workman to servo several machines. Fig. 406 shows a side view of the comb-filler ; and Fig. 407 is a plan of the same. The comb A to be filled is entered vertically from above, 406. within grooved guides 6 6 of a main frame B, secured to the side of a bench. The bristles C are entered transversely within the spaces c c, between the teeth d of the comb, and so as to overhang both sides of the latter in regular order, commencing with the space between the lower teeth, and repeating the filling operation, each tooth space, one above the other in succession, as the comb, controlled by pawls, drops down the grooved guides bb till it is wholly filled, when it is taken out from below for use in the machine, and an empty comb is inserted in the filler. Pivoted at e to the main frame in front, is a narrow lower jaw D, on and along which the bristles C are laid, so that they overhang both sides, being held in position by a fixed upper jaw E, which, with the lower jaw, grips them at about the middle. The introduction of the bristles between the jaws is effected by temporarily depressing the lower one, which is afterwards closed by a spring /. The open edge of the comb A, when in place, lies immediately behind the jaws, and the bristles are drawn into, and more or less compressed within, each tooth space c in succession, by toothed feeding bars F F, pivoted at g, to a pair of outside horizontal slides G G, which are slotted at A to receive guide pins , connected with the main frame. The toothed portions of the feeding bars F F lie over the bristles on the jaw D, and are held in a raised position, so as to be clear of them, BRUSHES. 553 by means of a spring / ; and a forward traverse motion is given to the slides which carry the feeding bars, by means of a spring H, and cord or chain k. To feed the bristles into a space c of the comb, power is applied by foot to a treadle below. This pulls upon duplicate cords m, which are connected with dogs I, pivoted on the feeding bars F F, and so arranged in relation to the slides G G and the stops n, that their first action is to draw down the toothed feeding bars F F into the bristles, and afterwards to draw the bars and slides backwards, by which the bars F F are made to distribute and pack, as required, the bristles within a tooth space c of the comb. The foot is then removed from the treadle, and the parts resume their normal position, to effect the filling of a succeeding tooth space, and so on till the comb is full. The comb A is retained in position and fed or allowed to drop as required, so as to bring each tooth space in succession into the receiving position for the bristles, by means of pawls J K, the former of which, catching in the holes s of the comb, simply serves to keep it from dropping too far while the latter is out of contact with the teeth of the comb, it being adjusted to enter suc- cessively within the tooth space c, to hold the comb at its precise required height. Towards the close of the back or feeding-stroke of the bars F F, pins on them strike levers, which, bearing against studs P of the pawl K, release the latter from the comb to provide for its next downward feed. When the feeding bars F F and slides G move forward again, a projection connected with them releases the pawl J to admit of the comb completing its drop ; the pawl K being now released from the action of the lever, catches between a succeeding pair of teeth, for repetition of the crowding of another lot of bristles within the next tooth space of the comb, and so on till the filling is complete. The Woodbury machine uses bristles, hair, tampico, or any other material equally well, and firmly secures the bunches in backs of wood, leather, indiarubber, bone, ivory, or other substances. It works 75 to 80 bunches per minute with the greatest ease, and fills an ordinary scrubbing-brush back in about the same time. Though extensively used in America, this machine has not been received with favour in England, an objection alleged against it being that the wire used for binding the bunch occupies so much of the hole as to prevent the bunch from fitting closely. Round Brushes. Round brushes for cleaning bottles, lamp-glasses, and other cylindrical vessels, are made by fastening the bristles, which project both ways, between two wires, which are then firmly twisted together. Steel Brushes. For cleaning and removing sand from castings, very durable brushes are made by substituting for the bristles, a series of flat, well-tempered steel wires. They are an American manufacture, and are sold at 5 to 18 dollars (say 23 to 75 shillings) per dozen, according to size. Iron-wire Brushes. Headed pins of ordinary iron wire are fixed in some elastic material, which is then attached to a thin sheet of metal, dished or bent so that the margin can be inserted in the undercut margin of a recess formed in the handle or back, as seen in Fig. 408. When the metal is bedded down upon the back a, the edges of the plate enter the recesses (Figs. 409 and 410), and it may then be secured by screws. If the plate be of steel or other metal having a degree of resilience, it may be sprung into place, and other fastening be dispensed with. The attachment of the elastic material to the plate is effected by sewing or riveting to the previously nicked or perforated plate, or by clamping over the edges of the plate, or by slitting them and turning up parts to be passed 554 BKUSHES. through the elastic material and clamped down. Fig. 411 shows a margin which has been slitted ; either needle and thread or rivets may be passed through. Fig. 412 is an example of clamping ; in Fig. 413, the teeth are pointed for forcing through the material. By another plan, the elastic material is fixed on a piece of wood by means of pins driven through the folded margin of the material and into the wood, or secured by stitches across the back, or by binding wire, &c., in a groove on the wood. The wood is then screwed to the handle, or cemented into a recess by shellac. Figs. 414 and 415 show the attachment by pins. In Fig. 414, the margin is so wide that it can be folded over the edge of the wood to the back ; pins c are then driven through, or the opposite margins at c c are sewn together across the back. Fig. 416 shows an oval piece of wood fitted with a groove d on the edge ; the edge of the material is folded over this, and embraced tightly by a coil of wire. In Fig. 417, the piece of wood is fitted into a recess in the \\\\uiiiinir/// handle or back /, which is of papier-mache, vulcanite, or of various moulded compositions. A hat- brush is shown in Fig. 418 : i is a piece of wood to which the material is secured ; it is then fixed in a recess formed in the wooden back k, which is covered with plush, whose edges are folded underneath, hidden and secured by the back. Some brushes are made without wooden backs, the elastic pin-set material being stitched or riveted to a backing of leather g (Fig. 419), to which a leather strap h is attached, forming a handle under which the hand is held when in use. This kind of brush is useful for grooming horses, &c. It is also possible to have a margin of "9- bristles around the metallic part of the brush ; in those having recessed backs, the wire for drawing in the bristles is concealed ; those having leather backs require the bristles to be wired in from the edge, as in Fig. 420, or from the back, as in Fig. 421. In the case of brushes with metal backs, such as cattle and horse brushes, the bristles are fixed in a strip of leather which is fastened to the metal back, and surrounds the wire pins forming the centre of the brush. Cylindrical brushes for brushing hair and other purposes are made by securing the pin-set material to the circumferences of the cylinders : preferably it is sewn to a strip of leather backing, and this is coiled spirally around the cylinders and cemented or tacked to them. Bass Brooms. Since the introduction of Piassaba (see Fibrous Substances), the manufacture of " bass brooms " has become an important branch of the brush-making industry. The rough " bass," as it is called, has to undergo a process of cutting, combing, steaming, " mixing," cleaning, and a : final secret process, by which it is rendered more durable, in order to fit it for the brushmaker. The principal consumers of this material are 3. and G. Horsey, of Mile End, who are the sole employers of machinery for making this class of brush. The backs or stocks are pierced partially through with holes, as by the Woodbury machine, before mentioned, and are automatically centered for the reception of the bunches. On one side of the machine, is a box filled with bass of the proper length, and at each revolution of the machine, a curious mechanism, called the " thief," darts into the midst of the bass, and abstracts just sufficient to form one bunch, which, being delivered to a travelling " carrier," is conveyed under the punch for fixing. Fig. 422 shows a section of the punch BRUSHES. 555 descending, and doubling up the bunch, at the same time forcing down a scrap of steel wire which, when down in place, is spread out, and holds the bunch in position, as shown in Fig. 423. Figs. 424 and 425 show a plan and sections of the wire, the bass being removed. The steel wire is run from an immense reel placed over each machine, whence it descends through a series of rollers, which deliver just so much at a time as will suffice to fix one bunch. Each machine, requiring the attendance of only one girl, can fix about 30,000 bunches per diem. Immediately the stock is filled, the broom passes through a set of combs, and between a series of knives, by which the surface of the bass is rendered flat and even. Finally, the backs are dressed smooth, and almost polished, by the action of a number of rotary and fixed knives. Figs. 426 and 427, both partly in section, show respectively a side view and front view of one of the machines employed in recessing wooden backs. A is a framing, on which is fixed a standard B, one side of whose projecting head is planed and formed with " vee " elides, to receive a eliding carriage C. In bearings formed in bosses on this carriage, a cutter spindle I is fitted to revolve, receiving motion from a strap m. The carriage can be slid to and fro by means of a screw operated by a handle n, and working in a nut fixed to the carriage, as in the case of a lathe slide rest. A shaft o is fitted to revolve upon an inclined axis, in a bearing p fixed to the framing of the machine. On the upper end of this shaft, is formed a head q, which is planed and made with vee slides, and upon this head a table D is fitted to slide. Corresponding parts are seen in Fig. 428, which illus- trates a modification in the machine. To the under side of the table, are secured two curved guide blocks rr, fitted to revolve around and in contact with an annular guide ring s, which is bolted to the table, but can be adjusted so as to be more or less eccentric with respect to the axis of the shaft o. If the ring s were fixed so as to be concentric with the shaft o, the table D would revolve with the shaft without sliding upon the head q, but when the ring is eccentric to the shaft, the table is made to slide to and fro on the head during each revolution. The table D is prepared to receive and hold in position the wooden back which is to be recessed. In the figure, the back marked E fits into a recess in the face of the table. A cutter F is fixed to the lower end of the spindle I. A revolving motion is imparted to the shaft o, by means of the worm and wheel G, the worm being fixed on a shaft t, driven by means of a strap. The back to be recessed is placed in position on the table, the carriage C having been slid away from the standard, so that the cutter would clear the work on completion of the back last operated upon. When the work is in position, the shaft t is started, and the work is thereby caused to revolve, and also to move to and fro in a direction across the axis of revolution. The carriage C is now moved in the direction indicated by the arrow, by turning the handle n, by which the cutter is brought into contact with the work. The movement of the carriage being continued, the cutter recesses the handle in all directions away from the centre, and, by the combined rotatory and rectilinear motions of the work, makes the recess of an oval form. The cutter is so formed that when the recessing is completed, which completion is determined by the further movement of the carriage being arrested by a stop, the margin of the oval recess is under- 556 BEUSHES. cut, as indicated in Fig. 408. For some purposes, the recess does not require to be under-cut, nor the bottom of the recess to be raised in the centre, for instance as in the case of Fig. 417. The action of the shaft o is then made vertical and not inclined. Fig. 429 is a side .elevation, partly in section, of a modification of the foregoing machine when made self-acting to a greater extent. In this case, the table D revolves upon a vertical axis, but in other respects is arranged to act in the same manner as the table in Figs. 426, 427, and 428. The cutter spindle I revolves upon an axis which is in- clined with respect to the axis of the shaft o, by which an effect correspond- ing to that of the first machine is obtained ; it revolves in bearings in a carriage C, which is fitted to slide at right angles to the axis of revolution of the cutter spindle. A worm u, fixed on the shaft o, and gearing with a worm wheel fixed on a cross shaft v, imparts a comparatively slow revolv- ing motion to the shaft, which revolves once during the recessing of a back or handle. Upon the shaft, is fixed a cam I, on which rests one end of a lever w, which is fixed upon a shaft J mounted in bearings. Upon the same shaft, is fixed a second lever x, the free end of which is connected by a link x' with the carriage C. This connection is made capable of adjust- ment. In the figure, the link is jointed to a nut, in which works a screw y, mounted in the carriage in such a manner, that when the screw is turned, the carriage is moved in one direction or the other, while the nut remains stationary. The cam acts upon the lever w, to effect the sliding of the carriage C in the direction indicated by the arrow. A weight L, attached to a chain which passes over two carrier pulleys z z, tends to move the carriage forward in a contrary direction to that indicated, and thus keeps the and of the lever w pressed upon the cam. A second cam M acts upon a lever a' mounted on the shaft J, and connected by a rod V with the strap guide bar of a counter shaft motion, from which the cutter spindle and the shaft i are driven. When a back to be recessed is fixed upon the table, and the machine is set in motion, the cam J slowly raises the end of the lever w, by which the carriage C and the cutter spindle are moved in the direction indicated, and the recessing is effected. When the recessing is com- pleted, the cam permits the weight to move back the carriage C, and, during this backward movement, the cam M begins to depress the end of the lever a', and thus to shift the strap which drives the counter shaft on to the loose pulley, so that by the time the backward movement of the carriage is completed the action of the machine is arrested. Brushes with Celluloid Backs. In making brushes with backs of celluloid or other similar eub- Btances, the material is formed ir moulds in two parts called half-shells. One of these is perforated with a series of holes for the tufts of bristles, whose inner ends are secured by being matted or ironed BUTTONS. 557 down upon the tinder side of the half-shell. A thin sheet of plastic material is now laid on, to further secure the bristles and keep them in position, this being covered with a wooden core extending into the handle of the brush, and strengthening it. This again is covered with the other unperforated half-shell, which forms the back of the brush, and the whole is then subjected to heat and pressure in a die, so as to mould the composition together, and close the holes about the tufts. In this way, a strong, cheap, and durable brush is obtained, in which there are no seams or joints to open during use, no cement to crumble and admit moisture, and no threads or wires to break off or rust out. Brush-making is a trade which may be carried on upon almost any scale, according to the capital at command. A man may start alone with half a dozen tools and a five-pound note, or he may employ hundreds of hands, and any number of machines driven by steam. The manufacture is not confined to any particular place or country, but is spread promiscuously over every civilized land. Imports and Exports. The imports of brushes to or exports from the United Kingdom are so trifling as not to be specified in the trade returns. The imports of bristles for brush-making, in 1877, were, from Russia, 1,162,634 Ib. ; Holland, 209,457 Ib. ; China, 100,006 Ib. ; Germany, 960,614 Ib. ; United States, 73,045 Ib. ; Belgium, 63,557 Ib. ; France, 57,894 Ib. ; other countries, 26,253 Ib. The exports for the same year were, to Belgium, 41,175 Ib., value, 3219/. ; other countries, 57,780 Ib. value, 8649Z. BUTTONS. (FB., Bouton; GER., Knopf.) Buttons may be said to mark the difference between ancient and modern styles of dress. The ancients, like the Easterns of to-day who have not put off old costumes for new, delighted in loose and flowing robes, rather flung around the body than deliberately put on ; but from the time of the Roman toga downwards, there has been a gradual departure from the antiquated dress in the countries of the West, and the fate of loose robes was sealed by the invention of buttons about a century and a half ago. The first end to which buttons were applied was that of ornament, and consequently in their earliest forms they were splendid and costly ; but men soon recognized their utility as a fastening for garments, which might thus be made less incommodious by reason of their fitting the person closely. It would be difficult to enumerate all the substances which of late years have been made to con- tribute to the manufacture of buttons ; but chief among them may be named gold, silver, copper, lead, iron, steel, brass, pewter, pearl, tortoiseshell, shell, ivory, bone, horn, hoof, hair, silk, Florentine (satin), linen, cotton, velvet, cloth, indiarubber, guttapercha, vulcanite, wood, amber, jet, glass, porcelain, enamel, clay, precious stones, leather, papier-mache', betel nut, vegetable ivory, or Corozo nut, and Manton's patent mineral earth as a substitute for the last named. Metal Buttons. These are made in two ways, either with a metallic shank for attachment to the garment, or perforated to admit the passage of the thread through the button itself. In the former case, they are usually manufactured by punching discs, out of sheet brass containing somewhat less zinc than ordinary brass, trimming the edges to remove the " bur," and planishing the faces under the action of a hammer to form the face of the button. This is embossed at the same moment that the maker's name is stamped on the back by means of cameo and intaglio dies. The shanks are formed of wire, which is run out by machine and cut off in sections of the proper length by a pair of shears, while a stud descends on the middle of the detached section, and forces it between the jaws of a vice, which give it the form of a staple or loop. It is then levelled by a blow from a small hammer, and dropped into a box. About a hundred of these shanks are taken out at a time and placed in position on the discs for which they are intended, being retained for the moment by a bent strip of flat iron. A scrap of solder is laid at the foot of each shank, and the whole set are then put on an iron plate, and heated in an oven till the solder melts. On cooling again, it fixes the shank, and forms a backing to the button. Each button is then turned separately in a lathe specially adapted, and afterwards gilt, electroplated, or tinned, as may be required. When the face only receives a plating, the buttons are known as " tops " ; when the whole is thus treated, they are called " all-overs." Though the gilding is exceedingly thin, it will receive a polish with agate or bloodstone burnisher. Metal buttons without shanks are turned out by stamping simply. Cast buttons are produced by suspending a number of loops of wire the shanks, with their ends expanded, in impressions in a mould, and pouring in the hot metal around them. When cold, the buttons are freed from sand, and chucked and turned in a lathe, when they are ready to receive polish or plating. Livery buttons are now probably the only ones on which the die-sinker is employed, they being the last remaining trace of the ornamental application of buttons. Covered Metal Buttons. These consist of three essential parts the metal framing, the textile covering, and the stuffing. The metal employed is exceedingly thin sheet iron, known as " taggers," made in plates measuring 14 in. by 10 in. The thickness generally used is No. 36 or 38, 558 BUTTONS. and the quality varies with the choice of the manufacturer. This is first scaled, the scales being removed by acid in order to preserve the tools, and then passed under a special punch. This punch is double, the outer portion cutting a circular blank of proper size, while an inner punch descends and forces the blank on to a die, so that its periphery is turned upwards, or so that the entire blank is rendered hemispherical in shape. These " shells " are next annealed in an ordinary furnace, and then conveyed to a horizontal revolving barrel, where they are tumbled with sawdust till thoroughly cleansed from all dust and grease. The under portion of the "shell," known as the "collet," is a somewhat smaller disc than the face, and is stamped out in an almost precisely similar manner, the inner part being punched out, leaving it with an annular shape. As the under side of the button is exposed, one face of the collet is japanned. A circular piece of the textile fabric to be used for covering the button is cut out by a die of the proper dimensions, and a pad or stuffing made of soft paper, silk, and thread (or sometimes of specially prepared paste-board covered with a bit of canvas) is punched into shape and fitted into the vacant space between the two metallic discs face and collet. The discs, stuffing, and cover are united to make the finished button, by stamping them in a press with concave and con- vex dies, the shank of soft material, through which the needle is passed laterally, protruding through the aperture in the collet. The press used in finishing the button is shown in Fig. 430. A is a fixed mandrel, B a sleeve thereon supported by a spring C. On the upper mandrel D, is another sleeve E, 43Q sustained by a catch F. The lower face of the mandrel D is hollowed, and a projecting annular portion of the upper sleeve enters a corresponding portion of the lower one E. In using the machine, a shell is placed over the lower mandrel, and above it is laid the textile covering. The workman then causes the upper mandrel to descend, by which the covering is pressed down around the shell, and, by the return upward movement, both covering and shell are carried up inside the sleeve E. Then is inserted the annular piece G, provided with a cavity suitable for receiving the combined collet, tuft-piece or shank, and stuffing, the last being uppermost. The upper mandrel is again brought down, and the shell is thus forced into the collet with its accessories, the covering being at the same moment turned under. This particular form of button ia called " iron-back," and is shown in its finished state in the figure. In another variety of the same class, known as " silk-back," the face consists of shell and cover, while the back is composed of four layers : A concave circular piece of taggers iron somewhat smaller than the shell, a paste- board blank, a canvas blank, and outside of all a silk blank. These are put together in the manner already de- scribed, and then a nipple for attachment to the garment is made by a press. The oldest and largest button-making firm in the United States turn out about 65 millions of iron-backs per annum, consuming for the purpose about 500 to 700 boxes of taggers iron, each weighing 112 to 120 Ib. The iron is of the very best quality, such as has only recently been produced in America. The various coverings lasting, brocade, twist, &c., and the canvas for forming the shanks, are all imported from England, France, and Germany. Another method of making covered buttons is as follows. The disc for the shell is left flat, and the back piece or collet consists of a smaller circular disc, with a round hole in the centre and having its edge cut into eight sharp points, which are so bent as to form nearly a right angle with the disc, but inclining slightly inwards. To complete the button, three pieces of paper and two pieces of cloth are required, and are arranged in the following way. On the cloth forming the outer covering, is laid a piece of paper of the same size, upon which is placed the iron disc forming the shell ; this is overlaid by another piece of paper the same size as the shell, and this again by a small piece of paper to help form the shank ; next comes a piece of coarse cloth, and finally the metallic collet. In putting on the back, the covering is gathered up over all the materials, and the points which are already inclined inwards are passed down into the covering, forming eight little hooks, which hold the button together in a neat and effectual manner. The paper stuffing forces the cloth to protrude through the hole in the collet, forming the shank for attaching the buttons. Pearl Buttons. The manufacture of buttons from mother-of-pearl is an important branch of industry, and is distinguished by the fact that no elaborate machinery, and not more than a few shillings of capital, are required. The whole work is done by means of a lathe and skilled hand BUTTONS. 559 labour, consequently any efficient workman can carry on the manufacture alone, and as a con- sequence, this particular kiiid of button-making is carried on by a large number of persons, each engaged in a very small way. There are several varieties of pearl, all composed of the nacreous gum secreted by several species of mollusc. The finest and purest specimens are obtained from the white-edged Macassar shells, imported from the East Indian seas, and worth in this country about 140J. to 1601. a ton. The yellow-edged Manilla shells are similar ; but the yellow tinge on the border reduces their value, and they are at the same time mere brittle. This variety is principally used in Sheffield for delicate knife handles, and fetches 1001. to 120/. a ton. A smaller and less deli- cate variety is found in the Persian Gulf and Ked Sea ; they are known as Bombay and Alexandria shells. Their quality is very various, and prices range from BQl. to 701. or 801. a ton. The islands of the Pacific Ocean yield a so-called black shell, which, when polished, throws out a dark shade full of rainbow tints ; portions also, when properly turned, give a white button, nearly as good as that from the best Malacca shells. The last and lowest variety, also from the Pacific, is the Panama shell, worth 20?. to 30/. a ton. The mother-of-pearl is cut out of the shell by a small cylindrical saw ; the disc is turned in a lathe, and, if thick enough, split to make two. A " dove-tail " hole is drilled in each button to receive the shank, which is fixed by a slight blow with a hammer, thus expanding the lower part into the dove-tail so as to prevent its being easily withdrawn. The waste from pearl-cutting has been utilized for button-making, by grinding it to a fine powder, and mixing it with gum, to form a paste, which, on heating, may be pressed in moulds. The beauty and iridescent brilliancy of mother-of-pearl are owing to thin plates overlapping each other unevenly, and dispersing the light as they reflect it. Ornamental flutings and corrugations are formed in the lathe by means of an eccentric chuck and slide rest. (See Pearl and Coral.) Porcelain Buttons. The process of manufacturing porcelain buttons resembles that of making email ornamental articles of earthenware. The moistened clay is pressed into plaster of Paris moulds, carefully placed on boards to dry, and then taken to the " biscuit-oven," where it undergoes the first firing or baking. The baked clay is now called " biscuit," and is ready for the painter or printer. A great number are made uncoloured ; but many also, both with holes and shanks, are partly or wholly painted, some with simple, others with complicated designs. The painting is effected either by hand or by transfer printing : in either case, the colours are " fixed " by the articles being baked in a muffle furnace or enamel kiln. In transfer printing, the design required is printed from copper plate, by means of a peculiarly prepared ink, on thin tissue paper, which is then placed, while the impression is still moist, upon the biscuit ware and allowed to dry, after which it is removed, the design having become transferred from the paper to the biscuit ware. The design is then burnt into the article in a muffle furnace. This baking effectually removes the oil used in preparing the colour, and leaves the button ready for the glazing process. Each muffle furnace is furnished with a little tramway, which traverses the interior of the furnace and projects forwards into the bakehouse. This tramway is provided with small, flat, movable iron platforms, on which the " frames " containing the buttons are carefully piled and then wheeled into the oven, around which a steady fire is kept constantly circulating. When the baking has been completed, the button is subjected, if required, to the glazing process, which is the same as that used for common porcelain, after which the shanks are added. (See Pottery.) Glass Buttons are moulded by pinching the material, while in a half soft condition, in a pair of hot pinchers, which are furnished with a die if it is desired to impress a design on the buttons. (See Glass Manufacture.) Shirt Buttons. Common white shirt buttons are made in the following way. Finely powdered steatite is saturated with soluble glass, the mixture is dried and repulverized, and the powder thus obtained is pressed into moulds by suitable machinery. It is then fired or baked in fur- naces, again dipped in soluble glass, and a second time submitted to the furnace. When cool, the buttons are polished by being put into a rotating barrel with water, then dried, and again polished by rotation in a similar barrel with soapstone powder. Turned Buttons. Buttons made from ivory, bone, horn, woods, and such like substances, are turned in a button lathe (Fig. 431), and the holes, varying in number from two to four, are drilled, while the button is in the lathe, by means of long drills converging towards the button and forming all the holes at once. The cutter of the lathe is like a centre-bit, only both wings are cutters instead of one being a router. On the tool revolving, the centre pin transfixes the sub- stance, and the wings circulating cut out a round disc, which is advanced towards the cutter by a 560 BUTTONS. eliding bar in the back poppet head. In the machine represented in the figure, the moving jaw of the clutch is forced against the blank by a spring, and drawn back again by a depression of the treadle. The bits are brought singly and alternately against the blank, being moved thereto by the bell- crank hand-lever. The woods chiefly employed are ebony, boxwood dyed black, and cocoa-wood. The so-called vegetable ivory or Corozo (Corosso, Corusco) nut consists of the hardened albumen of the interior of the nut, which is the fruit of a species of palm, Phytelephas macrocarpa, imported from the northern part of South America and from Central America. The nut grows in bunches as large as the double fist, but less than half of it is fit for use. It is milky white, lighter and softer than ivory, easily turned, and will take any shade of dye. Its value is about 251. to 30/. per ton. (See Nuts.) Button-moulds. These are little turned wooden discs perforated in the centre, and exactly resembling miniature quoits in appearance. They form the shell over which a covering of cloth or other textile fabric may be sewn, so that the pattern can always resemble that of the garment on which the button is used. They are principally made in the south of France, where suitable wood is not expensive, and are imported into this country by millions. They are used almost exclusively on women's and children's attire. Button Machinery. During the last four or five years, several improvements have been effected in button making and ornamenting machinery, the principal of which will now be described. An ingenious invention for polishing or finishing buttons made of horn, bone, wood, or Corozo nut, consists in subjecting them to frictional contact with prepared chalk, pulverized charcoal, or other fine cutting material, mixed with spirits of turpentine, naphtha, or such other liquid as, unlike water, will not "raise the grain" of the substance of which the buttons are made. They are by this means brought to a, better finish in a few hours than was hitherto possible in several days. When it is designed to ornament the buttons by " lining " or marking them with sharply-defined annular lines, they are subjected to frictional contact under pressure of a die having an axial movement, by which, in addition to securing the requisite smooth surface, the colour of any dyes previously applied is rendered more vivid and bright, and the " lines " are made without the raggedness of contour resulting from the use of a cutting tool. Fig. 432 shows a vertical section of the apparatus employed in polishing and " lining " buttons, on the line x x, Fig. 433, which is a horizontal section on the line y y of Fig. 432. In practice, the buttons are taken either as they come from the lathe, or, when coloured, as they come from the dye, and any desired number are mixed with about twice their volume (more or less) of prepared chalk, or other fine polishing substance ; to the whole, is added a quantity of spirits of turpentine, or naphtha, or, failing these, alcohol or kerosene may be used, but with inferior results. The mass is then placed in a common tumbling box, which is made to revolve for several hours, varying according to circumstances, and continued until the requisite smoothness of surface has been obtained. The bed A is provided at its forward end with a flat circular disc or carrier plate B, furnished at its periphery with radial teeth a, and, concentric with its axis, witli an annular series of holes 6, these holes having a dimension and form corresponding with those of the articles to be polished, and extending quite through the carrier plate. The carrier plate itself is furniuhed with a downwardly projecting axial shaft c, which works in a bearing formed in BUTTONS. 561 the fixed plate C, which last closes the lower ends of the holes 6, except as presently described. At the hack of the plate 0, is a vertical guide a', in which works a lifter D. Upon the upper end of this lifter, and within the guide, rests the die E, while around the upper portion of the guide, is a steam chamber b', furnished with steam pipes d connecting with a generator, and designed to heat the die E by circulating steam through the chamber. Arranged vertically, coincident with the lifter D and the die E, is a rotating die F, working in bearings provided in the lower part of the sliding head G, which moves in suitable guides A' fixed upon the bed A. Thia head carries an upright shaft G', upon the upper extremity of which are fast-and- loose pulleys and B', and which carries at its lower end a pinion D', gearing into a spur wheel F' on the rotating die F. The pulleys have a belt G* running to a shaft. The position of the two dies E F is such that, as the carrier plate B is intermittently rotated, the holes 6 will pass in succession immediately between the dies, to permit the upper or rotating die to pass through the holes, to act in conjunction with the lower die, which remains fixed except when lifted to discharge the finished articles. A slot is formed in the plate C, coincident with the adjacent portion of the series of holes 6, an 1 indicated in dotted line at e in Fig. 433 ; below it is an outlet chute /. The lower extremity of the lifter D is slotted, to allow a lever g to pass through it, one end of which luver is pivoted at one side of the frame A, while the other end is curved upward to rest upon a cam TO on a shaft H extending along the opposite side of the frame. The shaft H has a spiral disc h at its forward end, which gives an intermittent rotary movement to the carrier plate, insuring the retention of each hole 6 iu succession above the die E and below the die F for a certain definite time. The shaft H gears by bevel wheels n r with a bell-crank shaft J, driven by spur gears s t from a driving shaft K furnished with a pulley M for a driving belt. L is an elbow lever, whose extremity e" is pivoted to the lower part of the sliding head G, and whose free end connects by a pitman w with the crank m of the shaft J. To the bend of this elbow lever, is pivoted the bar z, whose upper end is pivoted to the fixed guides A', in such manner that the bar and the part e" of the elbow lever form, together a toggle joint, capable of giving a vertical movement to the head, from the rotation of the crank ; the down- ward stroke of the latter continually increases in power as the toggle joint straightens. M is a bellows which, being actuated during the downward stroke of the crank m, by the striking of the stud m" of the elbow lever L upon the arm n" of the bellows, sends a puff of air through its nozzle r" to blow away any dust which may have accumulated upon or near the dies. The method of operation is as follows : The buttons are placed singly in the holes 6, and by the movement of the carrier plate are brought under the rotating die F. The movement of the carrier being suspended for a moment, the sliding head G is brought down with great force by the straightening of the toggle joint, the die F on the head G being meanwhile rapidly revolved by the action of the belt on the fast pulley C'. As a consequence, the button is subjected simultaneously to great pressure and to the frictional contact of the die F upon its upper or outer surface, the force of the die corre- sponding in contour to the surface of the button. It is thus effectually smoothed and burnished, the colours are brightened, and the lines are sharpened without crumbling. This operation con- cluded, the continued working of the machine lifts the die F, whereupon the cam m raises the lever g, while the lifter D forces up the lower die till its top is level with the upper surface of the plate C. Then the action of the cam h on the teeth a turns the carrier plate B, until the hole con- taining the button is brought over the slot e, whereupon the button falls into the chute /, away from the machine. The same movement of the machine also brings the next hole into proper 2 o 562 BUTTONS. position with regard to the dies, so that the whole operation is continuous, and the work is per- formed with speed and economy. Figs. 434 and 435 represent an apparatus used to give a coloured ornamentation to buttons. N is the supporting framework, furnished at top with two longitudinal guides a, upon which runs a carriage P, having an upright cleat 6 at each end. Between these cleats, is extended a series of tightly drawn parallel threads i, whose distance apart will correspond to the space desired between the colour markings on the button. In the bottom of the carriage P is a disc, flat on the top but spiral beneath, fitting into a seat in the carriage bottom in such a way that when turned by means of the thumb piece e on the shaft /it will be raised, and, constituting the cam c, will lift the board R placed upon it. This board is indented in its upper surface with numerous cavities v, which receive the buttons to be ornamented, and retain them withtheir upper surfaces projecting somewhat above the corresponding surface of the board. By turning the disc or cam c, the board is lifted till the buttons are brought up s ! ngly against the threads '. W is the shaft of the cylindrical brush R*, and has a pulley a* furnished at the outer end with a crank ft 2 . Upon the frame below, are two pulleys , by which the piece of material is held in by pressure of a spring c, while the tools approach and perform the cutting. This spring is attached to a lever bar d, and the pressure is removed by a backward travel of the spring and its bar through the action of a plate, on which is a roller running in the race of cam /, on the forward end of the short shaft H, the release of the waste piece and the shaped button being effected by the attendant before putting iii a fresh rough piece. Sometimes a receiver is arranged between the fixed jaw and 2 o 2 564 BUTTONS. the movable one, so that the piece of rough material can be put in while the jaws are apart, thus preventing injury to the fingers. The receiver is composed of two wings or cup plates, which can be opened when the tools retire after completing the cutting, and allow the article and the waste to fall into a receptacle beneath, closing again for the reception of a fresh piece. The Figs, from 440 to 444, both inclusive, refer to a German improvement in presses and appliances for the manufacture of composition buttons in imitation of horn and vegetable ivory. It consists in providing the bed-plate A of an ordinary screw or lever press B, with a set of half- dies C, capable of being raised and lowered by a hand lever D, and sliding wedge plates formed of zigzag bars E E, which move in slots formed in a plate F, the upper part of which has chamfered or rounded-edged holes, in which the half-dies move. The " force " or head G of the press has upon its under side a corresponding number of half-dies H, these being formed by long pins or studs I, that they may pass through holes in a perforated plate J (Fig. 443), by which the composi- tion forming the buttons is fed to the lower half-dies. The plate is capable of easy removal for each feed ; it has a groove on each side-edge for a plain plate to be slid in to serve as a bottom, upon which the pieces of prepared composition rest when put into the holes in the perforated plate. The two plates act like a box ; when charged it is put over the lower half-dies C, and the plain plate is then drawn out and the pieces of composition fall down on to the top of the lower dies ; the force G is then lowered by rotating the handles L, and the pieces of composi- tion become transformed into buttons of a shape and thickness corresponding to the distance BUTTONS. 565 between the half-dies when the pressure la on. The half-dies, top and bottom, may have any device or design upon them, and one of them may have a couple or more of pins projecting to form the holes for sewing purposes ; or a short pin M may be upon, say, the upper half-die, by which the back of the button is formed, the pin M then making a hole of sufficient depth for the reception of a metal eyelet, shank, or loop, which can be inserted after the button is removed from the press. In fitting metal shanks to such com- position buttons, the shank pins are arranged in holes formed in a plate N ^ , ^ ^ (Fig. 444), and with the loops exposed that they may readily be taken hold of by a pair of pliers. This plate has a recess under it, in which a gas or other burner is fitted, for heating the plate, and for imparting sufficient heat to the shanks, that their pins may enter the holes in the button backs when applied, the heat softening the composition and forming the attach- ment of one to the other. The ingre- dients forming the composition, after being mixed in suitable proportions and of the colour desired, are placed in a caldron enclosed in an outer vessel, the space between the two vessels being filled with sand, to maintain an uniform heat. The composition, when heated to the proper temperature, is stirred and rabbled into a stiff pasty consistency, and used as desired. This is removed from the caldron in suit- able pieces and rolled in long strips, from which are cut smaller pieces, to fill the holes in the perforated plate. The rolling operation is done upon a hot plate, and the first-named perforated plate is heated partly by the hot plate and partly by the press, the half-dies in which are also heated, so that the composition, from the caldron to the finished button, is kept at about one temperature. The v. (O) pressure is maintained upon each series or group of buttons for a few seconds, and when the " force " is lifted, the first-named perforated plate is removed, and made ready for the reception of fresh pieces of the composition. The lower half-dies are then lifted by the sliding wedge bars, to lift the made buttons above the level of the holed plate on the bed. A many-tined fork is then put in between the raised half-dies, and the buttons are lifted off the dies by the tines, the superfluous composition being removed and thrown back into the caldron to be rabbled along with the other. The rough edge of each button is then dressed by a plunger tool. Instead of making holes in the buttons by the pressure operation, a cone-shaped lump can be left upon the back of each, through which a hole can be made parallel with the back by a heated piercer needle, the socket of which rides in a kind of box. The socket can be pushed in a given distance, to force the heated needle 566 BUTTONS. through the lump on a button put into a receiver or socket ; the socket then recoils under the action of a spring, and the pierced button can then be removed. The common practice in turning buttons, &c., is to employ a machine having two spindles mounted in line with each other, and revolving at a high speed, the cutting tools beiug fixed in the spindles, and the material to be operated upon being held between them by means of a o o o o o o OOOOOO ^OOOOOO OOOOOO oo o o.o c and "grip," together forming a pair of tongs. The grip and cutting tools are worked by the operator by means of handles, and require a considerable amount of manual labour and skill in their manipulation. An improvement upon this plan consists in actuating the grip and tools by means of cams in connection with levers and rods in a self-acting manner, so as to open and close the grip, and push one or both tools backwards or forwards as required, enabling a girl to do a large amount of work without great labour or skill. Figs. 445, 446, show a side elevation and plan of the machine suitable for turning buttons of wood, vegetable ivory, and similar substances: a is the framing of the lathe ; 6, 6' are spindles revolving in bearings on the framing ; at their ends they carry the tools for turning the front and back of the button respectively ; they are driven by straps taking on the pulleys c, c> ; d is the " grip " ; e, the " steady ;" k is a mm mounted on a spindle, revolving in bearings, and caused to turn by means of a pinion m, the teeth of which gear with teeth formed on the circumference of the crank ; the pinion m is mounted on a spindle, which is to rotate in its bearings by a strap taking on the pulley n. The crank is formed on the outside with a groove, in which works a roller I, mounted on a bar or connecting-rod g, which is guided at one end in the bracket q, and at the other end is attached to a spring/ by means of a screw r and nuts, as shown, whereby the tension of the spring can be regulated. The spring / BUTTONS. 567 is, by preference, jointed below, and serves to push the grip d against the piece of material. The groove in the front side of the cam k is shaped so as to make the grip self-acting, allowing the piece of material operated upon to drop in the moment the operation is finished, when the operator places another piece in the grip. The back of the crank k is also formed with a groove, in which works a roller I' mounted on a stud in the bracket ', which, by means of a set screw, is fixed on a square bar h that is guided in the framing a, but by preference works through stuffing-boxes. The bar A has a similar bracket t at the other end. Through the brackets t, ', are passed the screws/,/, which abut against the ends of the spindles 6, b' connected by the staples s, s', so that the spindles are made to partake of the movement of the bar, which is self-acting, and so timed and arranged by the shape of the back of the cam k that the tool on the end of the spindle b first cuts the face of the button, and then that on the end of the spindle 6' cuts the back of the button. There- upon the grip is opened, and the button falls out, a piece of new material is put in, and the opera- tion continues. Fig. 447 shows a part of a self- feeding appliance which is suitable for small articles that are turned very quickly ; t is a ring, which is made to revolve on four rollers placed equidistantly within it (not shown), formed with ratchet teeth all round, and actuated by a pawl. Motion is communicated by a lover and rod from a roller working in the outer groove of the cam k. The ring t is formed with holes in it ; at each hole is a spring u for holding the piece of material ; e is the steady. The pieces are fed in at leisure, and without the hand of the workman coming near the tools or grip. The next machine (Figs. 448 to 452) to be considered is an American invention, enabling all the operations of manufacturing covered metal buttons to be performed automatically. On a standard A, is a horizontal table, consisting of an under solid plate B, and turning in contact with it a plate C, having near its outer edge a series of holes c slightly larger than the button to be made. Above this second plate is a ring D, of the same size as the two circular plates, held stationary, but perforated with holes corresponding with those in the second plate. The bases of the holes in the plate C, being closed by the lower stationary plate, form a series of depressions in which the buttons are to be formed. The plate C is caused to revolve with an alternate motion by a suitable cam or ratchet wheel. At one side of the table and above it, in the line where the holes c re- volve, is placed a vertical tube E, terminating above in a hopper F, where are placed the fillings for the buttons, stamped of the proper size. A brush is made to vibrate among the fillings over the mouth of the tube, the effect of which is to keep the tube full when once it has been filled, and to lay the fillings flat in position, so that they may fall down one after another. The base of the tube is closed, but a slot is arranged in one side, just large enough to allow of the exit of one filling at a time, and a reciprocating bar G, entering at the opposite side of the tube, pushes the fillings out in succession, so that they fall through the holes in the upper ring D into the holes c as the revolving plate C turns round. A little beyond the tube of fillings is a hopper H for the metal faces. These are placed in the hopper H, whose bottom is inclined towards the centre from each end. In the 568 BUTTONS. centre, is a slot-shaped depression A', running across the hopper in a direction towards the revolving plate which turns beside it. It is but little larger than the metal faces, and just deep enough to allow them to catch and rest in it. The hopper tilts backwards and forwards, making the faces slide over the depression A'. The machinery for causing the tilting is a cam-wheel P, operating in opposition to a spring (not shown), against a roller p on the end of a connection, with an arm fastened to the hopper, and projecting below the point at which it is pivoted, so as to tilt In Fig. 451, one of the metal faces is seen in section, resting in the depression. In the hopper is 450. a vibrating brush or pad I, swung by the arm ', pivoted at J>, a pin passing through an elongated slot in '. The lower surface of the brush sweeps away any faces not lying in proper posi- tion. On the side of the depression A' towards the revolving plate, there is a slot in the side of the hopper H, through which the faces pass. After each tilting motion, the hopper pauses in a level position, owing to the shape of the cam wheel P which operates it, end the vibrating brush I being then also immediately over the depression, and the metal faces being lightly held in their position, they are pressed out of it by a reciprocating bar K through the slot k on the surface of the re- volving plate, where they all lie with their turned edges downward. While the hopper is tilting, the slot in the side may be kept closed by a spring (not shown), which may also be arranged to open the slot when the hopper comes to a level position. The reciprocating bar K is shown actuated by a lever M pivoted at m, motion being given in one direction by the cam wheel P having projecting cams at proper points on its face, which bear upon a roller O, in the end of a connection with the lever M. Motion in the opposite direction is given to the lever by a spring N. BUTTONS. 669 As the revolving plate turns, the metal faces are brought underneath a revolving brush L, standing above the plate and turning on a vertical shaft, arranged in a suitable bearing connected with the frame of the machine. The revolving motion of the brush L may be given by cords or belts from wheels 1. The operation of the brush L is to sweep the metal faces into a guide Q on the surface of the revolving plate, which conducts them one by one to the holes in the upper surface of the plate, into which the paper fillings have already been put. By this means, into each of the holes is placed a paper filling, and immediately over it one of the metal faces with its edge turned down, so as to embrace its sides. In case the revolving brush brings the metal faces to the entrance of the guide, which conducts them to the depressions in the revolving plate, more rapidly than the guide delivers them, the surplus metal faces pass off by the side of the guide and are carried around by the plate to the opposite side of the machine, where they are guided off by the guide R, and may then be placed again in the hopper H. Each depression is next carried by the revolution of the plate under a punch S, which is arranged to descend into each as it comes beneath, and by a touch adjusts the metal face over the paper, so that the edges of the metal will enclose the paper filling. Immediately adjoining this punch is another punch T, by the descent of which, as successive depressions containing the fillings and faces fall beneath it, each metal face is firmly pressed down into the depression over the metal face, and its edges clenched around the paper filling. By the shape of the same punch, any desired configuration may be given to the button. Immediately adjoining this second punch is arranged a third punch U, having at its extremity one or more pointed instruments (not shown), which punch the necessary holes through each button. The punches should be arranged at the same distance apart as the holes c, and may be caused to descend and rise by being attached to frames sliding in ways V, and operated by a knuckle-joint W, moved by connections with the crank shaft X. The button, by the operation of the punch last mentioned, is finished except japanning ; and after being carried a little farther by the revolving plate, is dropped through a hole in the under stationary plate into a recep- tacle beneath the machine, or it may be driven down through the hole in the plate B by a pin, operated by a sliding frame, the same as, or similar to, that which operates the punches. A compact arrangement for operating the several parts of the machine is shown in the figures ; the vibrating brush, the reciprocating bar G for expelling the fillings from the bottom of the tube E, the punches and the pin, being all operated by the frame sliding in the ways V. The same cam wheel P also causes the tilting of the hopper H, and moves the reciprocating bar K- The machine is operated by a crank or by power applied to the crank shaft X, and motion may be given to the revolving plate or table, and to the cam wheel P, and from it to other parts of the machine, through pinion wheels connecting with the main crank shaft X. When it is desired to make buttons with two metal faces, an upper and lower one with a filling of paper or other material between them, the arrangement and combination is modified so as to introduce a second hopper for holding the under metal faces. Both metal faces have turned edges, as before described, and one is made slightly smaller than the other, so as to go within the edges of the other. The fillings are made of a proper size to go within-the smallest of the metal faces. Self-fastening Buttons. Hitherto have been discussed only those kinds of buttons which, by means of holes pierced through them or by looped shanks attached to them, may be sewn on to garments with ordinary needles and thread. But an infinity of plans have been devised for making buttons which should be self-fastening, that is, possessing in themselves the means of attachment. One plan in very common use is to have a bent wire in the form of a figure oo , but open at one end, which is inserted through the looped shank on the button, after the latter has been thrust through the material of the garment. By another method, two small bell cranks with long and short arm are mounted on the shank of the button, and provided with angles against which a spring presses, keeping the bell crank in position after the style of the spring in the back of a penknife. A direct pull outwards suffices to dislodge the button when necessary. Sometimes links are used with a metal washer. A description of all the improved forms of buttons introduced, even within the last few years, is quite inadmissible, on account of the space it would occupy ; but it will be advan- tageous to refer to the principal half-dozen varieties, on account of both the ingenuity displayed and the principles involved. The form of a self-fastening button having a screw passing from the back of the material into the head of the button is shown in Fig. 453. Hart's self-fastening button consists of a button with a shank formed of strips of metal or wire which will bend without breaking, and provided with a washer (Fig. 454). a shows a transverse section of the button fixed ; 6 c, the two sides ; d, the button with the washer ; e, the washer ; /, the metallic strip forming the shank. The shank should not be so long as to subtend the washer when turned down. Fig. 455 (ff,6, and c) represents a button with a movable head, so that the shank may be placed through the button-holes. The head is hollow, is partly filled with caoutchouc, is perforated on the under side, and has an internal groove or recess crossing the perforation at right angles. The 570 BUTTONS. shank terminates at one end in a disc, and at the other in a short transverse bar, so as to form a cross head, as shown in a. To use the button, the cross-head D is passed through the button-hole in the fabric, and a caoutchouc washer is put on the shank B, to prevent it falling out when discon- nected from the button head. The shank is then secured to the head, by passing the cross-head through the aperture E (6) and turning it one quarter round, when it is forced into the groove M, and retained by the pressure of the rubber R ; c shows the complete button attached. Barnum's button, an American invention, shown in Fig. 456, consists of a long shank A formed into a T at the end ; and between the button and the cloth is a piece of rubber B through which the shank passes. A washer provided with a slot and a slight depression in it is placed at the back. The T is pushed through the slot and turned so as to fall into the depression, the spring of the rubber then draws the button firmly up to the washer, and holds all parts beyond the chance of slipping. The cloth is strengthened by the fastening, and the lap of the button-hole about the button is rendered better by reason of the space between the button and the fabric. imVi..Vk-^7rSftgffi^j^' x '^ In Fig. 457 is seen an automatic fastening by means of a shank shaped into head, iieck, and shoulder, passing through the fabric and fitting into a circular metallic socket in the knob of the button, the socket being so devised that on the shank being pressed in up to the shoulder the edge of the socket is forced to bend in and close round the neck of the shank and so prevent the latter being withdrawn: A shows the shank, with a the head, 6 the neck, and c the shouMer ; B shows the head of the button, with the metallic socket d in the centre, and the orifice of the socket of equal diameter with the head a of the shank. On the shank being inserted in the socket, and pressed in till the shoulder is forced against the thin metallic circumference e of the orifice, the latter bends inwards and closes round the neck of the shank as shown in C. According to another plan, the button consists of two parts, a head and a shank, held together by a spring of indiarubber or other material. The head piece is provided with a slot in the centre passing quite through the head, and a cross slot passing not quite through. The shank consists of a foot-plate, with an upright stem and cross-piece. When the button is to be attached, the cross- piece is put through the slot till it presses on the spring ; it is then given a quarter-turn, and falls into the other slot where the spring holds it. By reversing the operation, it can be taken out. Sometimes one or more spiral metallic springs are used to effect the same purpose. To obviate the button-hole from cutting through the thread which fastens the button on, the button is sometimes made as shown in Fig. 458 : a a is the base of contact of the button with the material ; 6, the annular surface to receive the button-hole ; c, a flange to retain the button in the button-hole ; d, a circular projection to prevent rubbing the thread. Holes are made through the bottom for fastening as usual. The button may be of any material, and either naked or covered. An improved linen button consists of a metallic blank having two holes for sewing on to the dress, which is laid in a recessed die or bed having a corresponding recess for the linen disc ; a sheet with an interior flange is then laid on the linen, and finally the back is put on the interior of the shell, and the whole is "closed up." The button is more durable than the ordinary form, and the cotton or thread, lying beneath the surface, is prevented from cutting in the wear. A form of solid leather button designed to strengthen the shanks and prevent their getting loose and coming out, consists of a fixed metallic plate or collar on the underside of the button, BUTTONS. 571 which plate is provided with a slot or hole in the centre through which the bow is passed. In the act of fixing the plate or collar on the underside of the button, the button is provided with a recess round the shank, into which the collar is dropped and firmly held by the pressure employed in the construction of the button. A substitute for shanks is composed of metallic prongs of round wire, or cut from sheet metal, secured to the head of the button in the same way as the shank, and varying in number. If preferred, a metallic collar may be used in combination with tLe prongs and placed outside them. The latter are then put through the collar in the act of fastening the button on the material, and the prongs are turned down within the collar and firmly driven in, as shown in Fig. 459, A and B. 457. 458. 469. 460. A proposal for doing away with the stiffness in fastening buttons is to have a ball and socket joint, the end of the shank being spherical, and moving in a hemispherical hollow, giving it a certain amount of flexibility. The last button that will be noticed is that shown in Fig. 460. It is formed as usual, except that the underside is made with a projecting neck, having a hole in the centre. On each side of the neck, is a slot in which slides a catch consisting of a slotted slide piece. The fastener ia composed of a stem of metal with a flange or collet at the lower end, the other end being pointed or coned and shaped with a groove at a short distance from the end. The figure shows the under- side of the button with the catch ; a, the underside of the button ; b, projecting neck ; c, hole in the centre of neck ; e, slotted catch sliding in the slots in the neck. The slot d is enlarged at one end, / corresponding with the hole c. The diameter of the stem of the fastener allows it to pass freely, but without shake, through c and /. Seat of the Industry. The principal button factories are distributed, in about the following pro- portions, in and around the towns named : London, 58 ; Birmingham, 161 ; Paris, 140 ; Brussels, 5 ; Vienna, metallic 15, porcelain 5, shirt 6, silk 11 ; Prague, several ; Berlin, 49 ; Barmen, 29 ; Liidenschied, 14 ; Elbcrfeld, 9 ; Hamburg, 5 ; Stuttgart, 6 ; Darmstadt, 3 ; Offenbach on Main, 3 ; Lubeck, 2 ; Breslau, 2 ; United States, 55, principally in New York (19) and Philadelphia (13). There are also several factories at Lyons, and one at Milan. As regards the home manufacture, Birmingham turns out principally metallic buttons, and exports large quantities of linen shirt-buttons to France, though unable to compete with her in some other classes. It produces also some few glass buttons, and consumes about 15 to 20 tons of Corozo nut a week, for making vegetable ivory buttons. For pearl button-making, it uses about 2 tons weekly of the best shells, and perhaps 20 tons of the inferior sorts. France manufactures far more buttons than we do. She exports immense quantities of wooden button moulds to this country, and is known for bone, pearl, vegetable ivory, and glass varieties, the chief factories being concentrated in some three or four towns distant 40 to 60 miles north of Paris. A few years since, France enjoyed almost a monopoly for porcelain buttons ; but since the destruction of Orleans by the Germans the trade has gone Rhinewards. Germany (including Austria) exports more buttons than France and England combined, supplying the markets of America, as well as those of northern, eastern, and southern Europe. She excels in cheap articles with a good outward appearance. Vienna is known for pearl buttons, eclipsing Birmingham in that branch, and several German towns have taken up the porcelain button-making, which does not seem to have made its way across the Atlantic as yet. Prague is now the great emporium for porcelain buttons. One works there possesses fourteen machines, costing only about 251. each, which turn out individually an average of 1600 buttons a minute. The great bulk of the glass buttons, too, are made in Bohemia, where the cheapness of labour and raw material enables them to produce a good article at an absurdly low figure about lie?, per 20,000, it is said. Imports and Exports. The values of the imports of all kinds of buttons, excepting metallic buttons, for the year 1878 were, from Holland, 405,210?. ; France, 192,236?. ; Germany, 32,309?.; other countries, 3551?. The value of all buttons (save metallic) exported from the United Kingdom to all countries, in 1878, was 7222?. (See Bone; Celluloid; Glass; Ivory; Nuts; Pearl and Coral ; Pottery.) CAMPHOR. (FB., Camphre ; GER., Kampher.) The name " camphor " is technically applied to a great number and variety of gum- resins, all of vegetable origin, and possessing more or less similar general characteristics, coupled with minor distinctive peculiarities. Three kinds only are objects of commerce ; they are derived from (1) Laurus camphora (Cinnampmum camphora, Camphora officinarum), the well-known camphor laurel of 572 CAMPHOR. China and Japan ; (2) Dryobalanops camphora (or aromaticd), a gigantic tree inhabiting the Malay Archipelago ; and (3) Blumea balsamifera. The products are known respectively as Common camphor, Borneo camphor, and Blumea camphor. Each of these will be considered under a separate head ; and, at the end of the article, will be added short descriptions of the less-known " camphors " of pharmacy. Common or Laurel Camphor. C 20 Hj 6 O. This is a colourless, transparent body, of tough, waxy, structure, having a specific gravity about equal to that of water, melting at 175 (347 F.), and boiling at 204 (400 F.). It volatilizes readily at ordinary temperatures, giving off the peculiar pungent aromatic odour which characterizes it. Recent researches prove it to be a phenol. It is very slightly soluble in water, to which it communicates its warm camphor taste ; but in alcohol, ether, fixed and volatile oils, naphtha, aniline, &c., it dissolves with facility. On subjection to the action of oxidizing agents, it is transformed into camphoric acid, and, if the oxidation be continued, camphretic acid, C 10 H, 4 O 7 , will result. The camphor laurel is a gigantic evergreen, bearing considerable resemblance to the common laurel, except in the matter of size, attaining, as it sometimes does, to a height of 50 ft. and a girth of 20 ft., with branches 8 or 9 ft. in circumference. The leaves are shining, and of a bright green colour, emitting a camphoraceous odour when bruised. The wood is white and fragrant, and is much used by the Chinese in carpentry, as it is proof against the attacks of insects. The chief habitat of the shrub ia the island of Formosa, where it reaches the greatest size, and where most of the camphor of western commerce is produced. It also flourishes in China, the Chusan Archi- pelago, and Japan ; the last-named country exporting considerable quantities of the drug. The shrub has now become naturalized in most of the tropical and warmer temperate countries of the world, as in Java, Brazil, Jamaica, and the West Indies generally, Cape of Good Hope, Mauritius, Madeira, and the Mediterranean region ; and it has been proposed to introduce it into South Georgia and Florida. It forms a large and handsome tree in sheltered spots in Italy, as far north as the Lago Maggiore ; it is commonly found in all the nurseries around Paris, and is not unknown in this country. The drug obtained from this laurel is prepared exclusively, or nearly so, for the markets of the West, and constitutes the only camphor of European and American commerce. As the native processes of collecting and preparing the substance vary in the different countries where the shrub is indigenous, it may be best treated geographically. 1. Formosa. In the district of this island included under Chinese territory, the camphor laurel is not found ; it is confined to the country of the aborigines, and its immediate borders. This circumstance is owing to the fact that the extraction of the camphor entails the destruction of the shrub ; as this destruction has never been compensated by replanting, the forest has been gradually cleared away, the aborigines receding and the Chinese encroaching as the work of destruction hns progressed. In consequence of the disturbed relations between the two races, thus induced on the border lands, the risk attending the camphor trade is very great, the distillers requiring to be always on their guard against attack; nevertheless, the industry maintains its ground. The method of preparing Formosan camphor is as follows : The shrubs, as required, are selected for the abundance of their sap, many being too dry to repay the cost and labour of treatment. The best part of the wood is secured lor timber ; while the branches and refuse are taken, while freshly cut, and chopped up into little pieces for distillation. The stills, built up in sheds and moved as the Chinese advance into the interior, are of very rude construction ; over eight or ten hearth fires, ia placed a long wooden trough, often a hollowed tree, coated with clay and half filled with water. Boards pierced with holes are fitted on the trough, and above these are placed jars containing the chips; the latter are surmounted by inverted earthenware pots, and the joints are made airtight by means of hemp packing. When the fires are kindled, the generated steam passes up through the pierced boards and, saturating the chips, causes the sublimated camphor to settle in crystals on the inside of the pots, from which it is scraped off, and afterwards passed through a second process of distillation to remove some of the impurities. At the bottom of a copper still, is placed a bed of dry powdered earth from an old wall (selected, doubtless, for the sake of the lime it contains), and on this a layer of crude camphor; this is again covered with earth, and so on alternately till the vessel is full, the series terminating with a stratum of earth, and being finally covered with green mint. A second vessel, usually formed of straw smeared with clay on the outside, is inserted over the still and luted on. The apparatus is placed over a regulated fire, and the contents are heated for a considerable time. After cooling, the camphor is found to have sublimed, and attached itself to the upper vessel. For transport from the interior, the camphor is packed in large vats or tubs, provided with escape holes at the bottom, and is stowed in carts of rude construction. Through these holes, exudes an oily or uncrystallizable liquid, known as "camphor-oil" (q. v. post). Almost all the camphor produced in Formosa is shipped from the free-trade port of Tarnsui, at the northern extremity of the island. It is the characteristic export of the place, and one of the most interesting, forming the main supply of the European markets. It is the only commodity, either of export or import, for CAMPHOR. 573 which the Transit Pass system is made use of. From Tamsui, the camphor is conveyed by native craft to Hong Kong, Shanghai, or Canton. Hitherto, owing to its being comparatively loosely packed, and containing a large percentage of water absorbed during its sublimation from the wood, the loss caused by evaporation during the journey between the two ports has been very large. The Customs allow for an estimated decrease of 5 per cent, (formerly 11 per cent, was the allowance) ; but the actual loss often amounts to 20 per cent. Lately, a hydraulic press has been established by one of the foreign firms trading at Tamsui, and the loss has thereby been reduced below the Customs' allowance. Chinese shippers have not yet learnt to appreciate the advantage gained; but it will be strange if they do not soon avail themselves of it. Until 1868, the Chinese Government enjoyed a monopoly of the Formosan camphor trade ; but it was then thrown open, with very bene- ficial results. In 1870 and 1871, attempts were made to re-establish the monopoly, under cover of a tax of less than a cf. per lb., in itself unimportant. With the removal of the objectional features of the impost, merchants have rested content, and things have gone smoothly since. There is no doubt that the supply of camphor laurels in Formosa is being gradually exhausted, though a number sufficient to satisfy the needs of many years still remains. The seaboard has been stripped of its shrubs ; but throughout the mountainous interior, the forests are still untouched. At Posia, a fertile plain among the hills in the middle of the island, Mr. Bullock's party, in 1873, found an abundance of camphor laurels; but the civilized aborigines inhabiting the spot are ignorant of their value. The prices ruling in Formosa, in 1872, gave a profit of 2 to 3 dollars (dollar = 4s. Id.) a picul (133J lb.) to the producer. For the western consumer, the Formosan camphor is reshipped, from the Chinese ports mentioned above, in square chests ined with lead-foil or tinned-iron, containing 1 J to 1J cwt. each. It consists of small dirty- greyish grains congregated together, their sp. gr. when pure being 98 to 99. It is always wet, as the merchants cause water to be poured into the cases before shipment, with a view, it is pretended, of lessening the loss by evaporation. The statistics of Formosan camphor production are as follow : 1870. 17,239 cwt., value in place, 29,080?. Of this quantity, 12,368 cwt. were exported, viz. : to China, 7890 cwt.; Japan, 2576; Bombay, 311 ; Strait Settlements, 1023; Germany, Holland, and France, 568. The bulk of that sent to Eastern markets was re-exported to the West, the portion which reached England being valued at 45,249/., or an average of 3/. 16s. Gd. per cwt. 1871. 11,537 cwt., value in place, 15,0487. 1872. 17,500 1873. 12,239 23,633. 1874. 14,380 25,666. Nearly all of this was sent to Hong Kong, and 3556 cwt. were ascertained to have been re-exported. 1875. 8,499 cwt., value in place, 1876. (About) 11,700 1877. 17,500 23,710/. Of which about 2700 cwt. went direct to non-Chinese ports. The imports of Formosan camphor to this country are about six times as great as those from Japan. 2. China. An inconsiderable quantity of camphor is produced near Chinchew, in the province of Fokien, on the mainland of China. The method of preparation, which differs from that in vogue in Formosa, is as follows. The freshly gathered branches of the laurel are chopped into small pieces, and steeped for two or three days in water; they are then boiled in a suitable vessel, meanwhile being continually stirred about with a stick, until the grains begin to adhere to it in the form of a white jelly. The fluid is then poured off into glazed vessels, and is left at rest for some hours, when the camphor will be found in a concreted mass. The crude drug is then purified as in Formosa. The shrub also flourishes in the Chusan Archipelago, growing to a large size if permitted ; the natives, however, only use the wood, and do not extract the camphor as on the main. 3. Japan. The camphor laurel is widely distributed throughout the three principal islands of Japan. It flourishes best in the southern portion of the empire, viz. in the province of Tosa, in Sikok ; the mild, damp sea-air favours its growth here, and the principal preparation of the drug is carried on in this locality. The districts of Satsuma and Bungo also produce considerable quan- tities ; the exports are chiefly from the ports of Osaka and Hiogo, and in much inferior proportions from Nagasaki. The distillation of the camphor is carried on throughout the year; but the best results are obtained in winter. The workmen choose a space where the trees are abundant, and there build a temporary dwelling and a camphor still. When the patch is exhausted, the buildings are taken down and trans- ported to another locality. The distilling process is very simple ; but is much in advance of the methods practised in China and Formosa. A tree is chosen, and as soon as it is felled, the trunk, large 574 CAMPHOR. roots, and boughs are cut up into small uniform chips, by means of a short-handled axe, and are drawn in barrows to the still. This is commonly placed on an incline, in the neighbourhood of a rivulet, which will furnish water for the wet distillation of the camphor. The most general arrangement of still and condenser, adopted in the Tosa district, is shown in Fig. 461. On a small circular stone wall A, serving to form a fire place, lies an iron plate F, 2 in. thick. This is covered by a numerously perforated lid, luted tightly with clay, which at the same 461 - time forms the bottom E of the vessel B, which is 3 ft. 4 in. high, and 18 in. wide at the top. Near the bottom is a square opening D, which may be closed by a board. -The whole is clothed with a thick coating of clay C, held fast by a binding of bamboo hoops a. The upper opening is closed by a clay luted cover G, having a hole in the centre, furnished with a cork K. Just under this cover, a hollow bamboo stem leaves the still, and passes to the condenser H. This consists of a four-sided box open beneath, divided into five inter- communicating compartments by means of four partitions, and turned with its open side into a vessel M containing water. This condenser is kept constantly cool by a stream of water, led over the top by means of the pipe 6. The distillation is conducted in the following way : After removing the cover G, the vessel B is filled with the chips of camphor wood, the cover is replaced, and well luted with clay ; then through the opening K, a certain quantity of water is run in, which, after saturating the chips, will collect in the pan F. Gentle firing is now commenced, and is continued for twelve hours, so as to keep the water in F at a steady boil. The ascending steam, finding -its way among the chips, carries all the camphor with it, and, on conden- sation in the cooler H, the camphor is deposited. After 24 hours, operations are suspended, the whole apparatus is cleaned out, and the camphor collected in H is removed into tubs. Here it is subjected to very gentle pressure to extract the oil, which amounts to 25 per cent, at least, and is quite limpid. In some districts, the raw camphor is submitted to a second, somewhat stronger, pressure, by which a greater proportion of the oil is forced through the joints of the casks. The two products are then ready for market. The camphor exported is never quite pure ; it always needs to undergo a process of purification after arrival in Europe. The waste chips, after drying on the grating I, are used as fuel. Japanese camphor is distinguished from Formosan by being coarser grained, clearer, of pinker hue, and by subliming at a lower temperature. It is also known as " Dutch," or " tub " camphor, the latter name arising from its being imported to Europe in tubs covered with matting, each placed within a second tub, secured on the outside by hoops of twisted cane. No metal lining is used, and the camphor is thus drier than the Formosan. Each tub holds about 1 to 1 J cwt. The selling price is nearly twice as high as the Formosan, and the imports to Europe are about as 1 to 6. The amount of camphor exported from Japan, in 1870, was about 2360 cwt., principally to China (2171 cwt.); Straits Settlements (51 cwt.) ; and France and Germany (139 cwt). Its value in the selling market was 14,498/., or about 61. 2. lOd. per cwt. In 1871, Hiogo and Osaka exported about 8450 cwt., and Nagasaki about 900 cwt. more : the total value was placed at about 25,0007. In 1872, the value of the export was stated at 30,576Z. In 1876, Hiogo and Osaka exported about 10,000 cwt. The imports of common camphor into the United Kingdom, in 1870, were: Unrefined, 12,308 cwt. ; refined, 2361 cwt. Imitations of Common Camphor. It is said that camphor has been prepared from the roots of the cinnamon shrub, and finds a ready sale in Ceylon and other parts of India ; report also states that it has been obtained from several of the Labiatae, notably in Spain. An imitation camphor is some- times made in Japan ; but it is readily distinguishable from the genuine article. An artificial chemical product, bearing a close outward resemblance to camphor, is obtained by passing hydro- chloric acid gas through oil of turpentine surrounded by ice. Two compounds are produced : solid artificial camphor, C 20 H 16 HC1, white, transparent, lighter than water, and possessing a camphoraceous taste ; and a liquid known as " terebine." This preparation has not been admitted into pharmacy, and is little more than a laboratory curiosity. It is easily recognised by the re- action with ammonia. If natural and artificial camphor be dissolved in alcohol, the former will CAMPHOE. 575 not be precipitated permanently by ammonia, while the latter produces a flocculent precipitate, which is not dissolved in the supernatant liquid. Eefining Common Camphor. The crude camphor consists of small crystalline grains of greyish- white or pinkish hue, cohering in irregular, friable masses ; this, when dissolved in spirits of wine, leaves a sediment of 2 to 10 per cent, of impurities, composed chiefly of common salt, gypsum, sulphur, and vegetable matters. The latter are removed by careful distillation, in the presence of a little quicklime to absorb the oil, &c. Two earthen pots luted together, and having a small aperture provided for the escape of the air on the first application of the heat, answer the purpose roughly. In this way much camphor is refined by the natives of India. They buy it in the cases as it arrives from Chinese treaty ports, paying about 34 rupees (rupee = 2s.) a Surat maund of 42 Ib. The process is illustrated in Fig. 462, and is conducted as follows : About 1 maund of camphor are mixed with 2 seers (seer = If pint) of water, and placed in a copper still A, about 2 ft. high. This quantity of camphor is made into a pyramid, and after 46a - it is piled into the vessel, an additional 2 seers of camphor (? or water) are thrown in round the sides. A copper lid E is then put on, and, to make it perfectly tight, an iron bar is passed through it and the vessel by holes made for the purpose. The still is then lifted by handles, and set on an earthen chula B, below which fires are burning. The lid and edges of the still are smeared with wet clay, which is also piled up into a cone. In about fifteen minutes, steam comes through the hole where the bar goes, whereupon a cloth C attached to a bamboo is dipped into a receptacle D filled with water, and mopped over the clay cone on the still, so that the water keeps the upper portion cool. This is maintained for three hours, when the sides of the still are beaten with a stick. If this produces the sound of an empty vessel, it is known that the process #f sublimation is complete ; the still is then removed from the chula, and the lid is opened. The camphor is found in a thick crust lining the upper part of the sides of the still ; it is divided into four pieces by a flat iron knife, and packed in boxes for sale to the dealers. The refining of camphor in Europe was long confined to Venice ; but it is now carried on largely in England, Holland, Hamburg, and Paris, the product being much finer and purer than that obtained by the crude processes of the East. In England, the operation is performed as follows : The impure camphor is broken up, mixed with 3 to 5 per cent, of highly slaked lime, and 1 to 2 per cent, of iron filings. These are well sifted, and introduced through a funnel into the necks of a series of bomboloes, flasks of thin flint glass, with flat bottoms and short necks, the name being of Venetian origin. These are placed in sand baths, which are heated by dishes of fusible metal, kept at the proper temperature by means of a furnace outside the room. The object of this is to avoid the necessity for bringing fire into the presence of the very inflammable vapour given off by the camphor. When filled and in place, the flasks are covered with sand to the neck, and rapidly heated to 120-190 (248-374 F.) for half an hour, to expel the water. The temperature is then gradually raised to about 204 (400 F.), and maintained at this point for about twenty-four hours. As the temperature increases, the camphor softens, and at last melts. When the mass has become fluid, the sand is removed from the upper part of the flask, and a paper stopper is put into the neck to partially close it. The heatis then carefully preserved at a point sufficient to sublime the camphor, but not to remelt it, so that it re-solidifies on the interior upper part of the flask as a semi-transparent cake, leaving all impurities behind. The temperature of the refining room is about 65 (150 F.), the air being very dry, and highly charged with camphor. To diminish the escape of camphor vapour during the process, each bombolo is covered with a glass shade ; another use of this is to exclude the air, whose presence would make the sublimed camphor opaque instead of translucent. The whole process lasts about forty-eight hours ; it requires the greatest attention and experience, on account of the inflammability of the substance, and the necessity for regulating the temperature very nicely, so that the sublimate may be deposited, not merely in loose crystals, but in compact cakes. When the sublimation is completed, the flasks are taken out, and cold 576 CAMPHOB. water is sprinkled on them. This causes them to break, and the now pure camphor is removed from them in the form of large bowls or concave cakes, like gigantic quoits, about 10 or 12 in. in diameter, 3 in. thick, and weighing 9 to 12 Ib. The bomboloes weigh about 1 Ib. each, and measure about 12 in. across. Sometimes a little charcoal or sand is added to the lime, and, when sulphur is present, iron filings are a useful adjunct. Following is an account of the Dutch method of purifying. To every pound of camphor, is added about 2 oz. of lime ; the two are well mixed in a mortar or small mill, and about f Ib. of the mixture is put into each still. These consist of black glass flasks of round form and with long necks, a certain number being placed in a row on sand baths heated by a furnace beneath. They are buried some inches in the sand, and tightly stoppered with cotton or tow. Under each sand bath is a furnace and ashpit. To commence with, a gentle fire is made so as to liquefy the camphor. The steam rises into the neck, and would condense and fall back into the still in drops if it were not prevented. Each still is furnished with a conical hood or cap of tinned iron, which is covered with warm sand, and in which the vapour collects. In this way, all danger of breaking the still, by drops of camphor falling back, is avoided. When the camphor is fluid enough, and all the moisture has been eliminated from it, the sand is removed from the hood, or the latter is replaced by another, having a hole in the middle, to admit an iron implement for stirring up the mass in the still. As the camphor evaporates, it condenses again on the sides of the cap, and there forms a transparent mass. All outer air must be rigidly excluded. When the hoods have been exchanged, and the moment the sublimation begins, the fire is reduced. The temperature is maintained at the proper degree for a whole day. From time to time, the workman removes the cap and the cotton stopper, in order to stir up the stuff at the bottom of the still with an iron tool, and to keep the passage of the neck open, as ihe condensing camphor has a tendency to choke it up. Towards the end of the operation, the cap is altogether removed. The end is known to have arrived when the camphor collected on the sides begins to melt. The flasks are then taken from the sand- baths, cooled and broken, to extract the mass of camphor ; this is then wrapped up in blue paper. Much camphor still remains in the fragments of the flasks, and as it would be too troublesome to scrape it off, the pieces are thrown into a very deep copper still, which is covered with a circular copper hood, and placed over a fire. The camphor collects as before around the hood, and is then easily removed. During the sublimation in the flasks, the temperature is maintained at 120 248 F.) for half an hour, and is then raised to 190 (374 F.) ; at this point, the neck will be coated with moisture, which must be removed by inserting a sponge on a flexible stick. A temperature of 190 to 196 (374 to 385 F.) will melt all the camphor in three and a half hours. The residue is sublimed in a cast-iron vessel, and the little product obtained is thrown in with the next lot of raw camphor. Uses. The -applications of common camphor are restricted almost solely to medicinal and antiseptic purposes. Borneo Camphor ; Malay Camphor ; Borneole ; Camphyl Alcohol ; or Kapur Barus. This is quite distinct from the camphor of western commerce. It is expressed by the formula C 20 H, 8 O 2 , or two additional equivalents of hydrogen. It fuses and boils at higher tem- peratures than common camphor, is harder and more brittle, of greater specific gravity (1'009), less volatile, and doos not crystallize on the interior of a bottle when kept. Its crystals are coarse and resinous looking, about J in. broad on the faces, and of different form from the ordinary drug. In the chief feature, viz. aroma, it closely resembles common camphor, but is less pungent. It is the product of a magnificent forest tree, the Dryobalanops camphora, or aromatica, which often reaches a height of 90 or 100 ft. to the first branches, overtopping all its neighbours, and presenting a handsome head of dense foliage. The trunk often attains a girth of 17 to 18 ft. According to the natives of the Malay Archipelago, there are three kinds of this tree, named respectively mailanguan, marbin tungan, and marbin targan, from the outward colour of the bark, which is sometimes yellow, sometimes black, and often red. The bark is rough and grooved, and overgrown with moss. The leaves are dark-green, oblong-oval, and pointed ; they smell of camphor, and are hard and tough. The exterior form of the fruit is very like the acorn ; but it has around it five petals, placed somewhat apart, and the whole much resembles a lily. The tree flourishes to greatest perfection between the altitudes of 250 and 400 ft. above sea level; but is also found in dry (that is, not marshy) places near the sea coast, and rarely at an elevation of 1000 ft. Its chief habitat appears to be the extensive bush of the Batta country, on the west coast of Sumatra, north of Ayer Bangie ; it is also found in the mountains of Santubong, Marang Sundu, and Sugony ; in Labuan ; in all the northern parts of Borneo, and it is eaid to be particularly abundant in the country of the Kyans, on the upper reaches of the Bintulu and Rejang rivers. The camphor is secreted, in the form of coarse crystals, in the hollows and interstices of the body of the tree, especially in the knots, and swellings of the branches from the trunk ; but it is not found in every tree, some observers remarking that only about one tree in a thousand appears in a condition favourable to the secretion of the gum. The natives have no means of estimating the CAMPHOR. 577 quantity of camphor in a tree, and though they know that it increases with age, the latter is always an element of uncertainty with them. Trees in a state of decay often contain the most camphor. The drug is gathered at irregular intervals, according to the fancy of the Rajah on whose territory the trees are. About thirty men start into the forest ; select a place where the trees are most numerous ; aud build rude huts, which sometimes form their dwelling for months together. They divide into two parties, one felling the trees, the other extracting the camphor. The tree is cut down just above its roots, divided transversely into several logs, and these again are split with wedges into small pieces, from the crevices of which the camphor, if there be any, is extracted.- That which comes away readily in large, semi-transparent flakes is esteemed the prime sort or "head " ; the smaller clean pieces are considered as " belly " ; and the minute particles, chiefly scraped from the wood and often mixed with it, are called " foot." The last is separated from its impurities by steeping it and washing it in water, sometimes with the aid of soap. It is then passed through sieves or screens of different meshes, in order to make an assortment as far as regards the size of the grains ; but much of the selection is also made by hand, and particular care is taken to distinguish the better kinds from that produced by the artificial concretion of the essential oil. The quantity of camphor yielded by a single tree probably averages about 10 Ib. Its commercial name is Kapur Bdrus, the first word signifying camphor, and the second being the name of the Sumatran port whence this article is mostly shipped ; it is sometimes called " bamboo camphor," from the fact of its being transported from the interior in hollow stems of that plant. It is in such great demand among the Malays and Chinese for embalming their dead, that it is only met with in Europe as cabinet specimens, the whole produce being consumed in loco. Thus the Chinese export to us their own Formosan product, while they import Kapur Bams, paying as much as 121. 10s. a catty (1| Ib.) for the best quality. The production of the drug is lessening yearly, and the profitable operations of 1753, when fully 1250 Ib. were shipped from Padang, will probably never return. Trees are cut down at random without any being replanted, and this wilful and wasteful destruction will, it is feared, soon place the tree among the past species of the Archipelago. Propositions have been made to Government to have regular plantations formed in suitable localities (as is done with the teak tree in Java), notably in the district of Ayer Bangie, Ban, and Tapanolie Eesidence. 1 he plants, four to six days old, may be transported in boxes half filled with wet sand, the contents being kept carefully wet and covered over with linen. The tree yields several products besides the camphor. First may be cited the well-known camphor oil (q. v. post). The fruit, when fresh and well ripened, is eaten by the natives. The height of the tree prevents the fruit being gathered, but when it fulls in March, April, and May the people go out to collect it. Prepared with sugar, it forms a very tasty preserve. It is said to be very unhealthy to remain near the tree during the flowering season, on account of the extraordinary hot exhalations given off by it. The wood of the tree is very tough and durable, and much valued by the natives for ship-building purposes. Its strong camphoraceous odour guards it against the attacks of the kepang, the destructive worm of those seas. It is adapted to making planks, beams, keels, stringers, and timbers, and has been proved invaluable for wharves and jetties. From its oiliness, it takes fastenings well, and iron is not liable to rust in it. Its weight is said to be about 70 Ib. per cub. ft. At Johare, large steam saw-mills have been erected for the purpose of preparing the wood for export. The following meagre statistics are all that can be found regarding this camphor: The quantity imported into Canton, in 1872, was stated at 3159 Ib., worth about 80. a Ib. In 1872-3, 2 cwt. were imported into Bombay, valued at 914/. The value of the production in 1873 was 1043 | 1875 was 3179 (about 5 cwt.) 1874 2578 | 1876 2337 Blumea, or Ngai Camphor. A third variety of camphor is manufactured in China from the Blumea balsamifera, a tall herbaceous Composita called Ngai in Chinese, and abundantly distributed throughout tropical Eastern Asia. When in a crude state, the drug appears in dirty-white, crystal- line grains, contaminated with vegetable remains; when pure, it takes the form of colourless crystals an inch long. It resembles the Bornese camphor in every particular, excepting in optical properties. Its value is about ten times that of Formosan camphor, and on this score it occupies an intermediate place between the two principal varieties of camphor. It is quite unknown in Europe; but in China it is much used, partly for medicine and partly for preparing the fine Chinese inks. The manufacture of this kind of camphor is carried on principally at Canton, the exports from which place are valued at 3000/. per annum. A camphor-yielding plant which is closely allied to the preceding, if not identical with it, is the Blumea grandis, a native of the Tenasserim provinces, where it flourishes exceedingly, and grows to a height of 6 or 8 ft. Its leaves resemble those of the mullen, and, when bruised, emit a strong camphoraceous odour. Many years ago, the Tavoyers informed Mr. Mason that they were in the habit of making an impure camphor from the weed by a very simple process. Latterly, this has 2 P 578 CANDLES. been improved upon by an Englishman, and the article lias been brought into public notice. More than 100 Ib. of it were refined and sent to Calcutta, and could not be distinguished from Chinese camphor. The plant is so abundant in the Provinces that they might supply half the world with camphor ; wherever trees are cut down, this weed springs up. Other Camphors. Besides the three principal camphors of commerce, the following are more or less known in perfumery and pharmacy, viz. : Barosmi Camphor. The leaves of Earosma betulina yield on distillation about 1 per cent, of a volatile oil, which solidifies on exposure to cold, and, after re-solution in alcohol, forms needle-like crystals, possessing a nearly pure peppermint odour. Bergamot Camphor, or Bergaptene, is a product of the bergnmot tree, a member of the Citrus genus, cultivated principally at Eeggio, in Calabria. From the full-grown but still unripe fruit, gathered in November and December, an essential oil is expressed. For a period of some weeks after its extraction, the oil gradually deposits a mass of white greasy matter, which, when distilled with water, produces bergamot camphor. Cincebene Camphor is obtained from the essential oil of a variety of the wormseed, which grows especially about the Don and Volga, and in the Kirghiz deserts. Cubebs Camphor, or Hydrate of Cubebene, is a deposit formed in cold weather from the oil of cubeba. Neroli Camphor. The fresh flowers of the bitter orange, when distilled with water in copper stills, yield an essential oil, most of which passes over on redistillation : the addition of an equal quantity of alcohol to the portion remaining in the still causes a little Neroli camphor to collect on the surface. By re-solution in boiling alcohol, it can be produced in a crystalline form. 0ms Camphor is the solid crystalline substance obtained by the distillation of orris root with water. Patchouli Camphor. The substance known in perfumery and pharmacy under this name is homo- logous with Borneo camphor. It is solid; fuses at about 51 (130 F.), and boils at 295 (563 F.); its specific gravity is 1-051 at 4 (40 F.); it is insoluble in water, but readily soluble in alcohol and ether ; it crystallizes in hexagonal prisms ; finally, it is a left-handed rotary sub- stance, while Borneo camphor is right-handed. Sassafras Camphor is yielded as a crystalline deposit, by cooling:, in a freezing mixture, the volatile oil procured from the roots and bark of the sassafras shrub of America. Thyme, Camphor of, or Thymol, is a crystalline product of the fractional distillation of essential oil of thyme. Tobacco Camphor, or Nic6tiania, is produced by distilling tobacco leaves with water. Camphor Oils : a. Malayan. During the collection of the camphor from the Malayan camphor tree, that is while the tree is being cut up, an oil drips from it in considerable quantities. Some- times it is obtained also by tapping the living trees ; but is not considered of sufficient value to warrant the destruction of the tree. The method of gathering this oil, as practised by the natives of Sumatra, is to make a transverse incision in the tree to a depth of some inches, the cut sloping downwards so as to form a cavity of the capacity of about a quart. In this, a lighted reed is placed for about ten minutes, and the hole is left for the night, when it becomes filled with the oil. This volatile oil, known as Borneen, holds in solution a resin, which, after a few days' exposure to the air, is left in a syrupy state. It is probably camphor in an undeveloped state, as the tree would yield camphor if left. It is seldom brought to market, probably because the price obtained is not a sufficient remuneration for the trouble of transport. Whenever it is offered at Barus, the usual price is a guilder (Is. 8d.) for an ordinary quart bottleful. b. Formosan. This is a yellowish brown, oily, or uncrystallizable camphor, which exudes from the cases of crude common camphor, to the extent of 3 or 4 per cent. It is very strong smelling, and holds in solution an abundance of common camphor, which it speedily deposits in crystals when exposed to a low temperature. Its symbol is C 20 H 18 O ; its density is 0-910. By exposure to oxygen, or the action of nitric acid, it absorbs oxygen and becomes solid camphor. It is much used by the Chinese as an embrocation, especially in rheumatic diseases, and will probably soon be a valuable European import as a cheap substitute for Lin. Camphorce. It is scarcely saleable on the spot, and is considered much inferior to the Malayan camphor oil, from which it is distinguished by an odour of sassafras. In Japan, the oil is expressed from the camphor, and is employed as a lighting material by the very poor people, who are content to burn it in open lamps, in spite of its powerful odour and heavy smoke. A recent native Japanese paper says that a resident at Osaka has built a large factory for preparing this oil, not for making oil out of camphor, as Nature says which has proved superior to kerosene, both in cheapness and illuminating power. (See Drugs ; Inks ; Oils ; Perfumes ; Besinous Substances.) C. Q. W. L. CANDLES. (FB., Bougie ; GEB., Kerze, Licht.) The use of wax candles as a source of artificial light dates from the middle ages, though, from the costliness of the material, it was probably confined, for a long period, to the dwellings of the CANDLES. 579 wr-althier classes. Until the introduction, in comparatively modern times, of tallow and vegetable fats, the substitute for wax caudles in the houses of the poor, and still to be found in some country districts, was the ordinary rush-light, which is the simplest and most primitive form of candle known. The use of candles made from tallow and palm oil, and various compounds prepared from them, as well as from wax, paraffin, and other substances, has of late years largely increased, and the manufacture has assumed very considerable dimensions in some of the larger towns of Great Britain, and on the Continent. A caudle consists essentially of two parts : (1) the combustible material ; and (2) a porous sub- stance through the medium of which combustion takes place. The first portion of the candle, the combustible material, is composed of various fatty or hydrocarbonaceous matters ; and the second portion, or the wick, the type of which is found in the rushes employed by our forefathers, is usually made of cotton. Before proceeding to describe the manufacture of candles, in itself a simple operation, the materials of which they are compounded, which are very varied and complex in their nature, must be fully dealt with. THE COMBUSTIBLE MATERIALS EMPLOYED. These are chiefly tallow and vegetable fats, and substances prepared therefrom by complicated chemical processes ; also wax, spermaceti, paraffin, ozokerit, &c. Tallow. Tallow is simply beef or mutton fat, or a mixture of both, prepared by being heated in contact with water and under slight steam pressure until the membranous matters in which it id enveloped aggregate into lumps, and collect in a layer between the tallow and the water, when the steam is turned off. For candles which are to be moulded from tallow alone, mutton suet is employed, while the commoner or coarser tallow is kept for those which are to be dipped, and also for the preparation of stearic and other fatty-acids. When melted tallow is allowed to cool very slowly, and without disturbance, it separates into two portions, one much harder, and the other much softer, than the original tallow ; and if the temperature of the whole mass does not fall below 24-27 (75-80 F.), it will consist of hard, round nodules, suspended in a liquid oil. This process is technically called " seeding," and the idea of separating the solid from the liquid constituents of fats, by exposing them to pressure while in this condition, originated with the French chemist Chevreul, in 1823. The researches of Chevreul and others demonstrated the following facts with reference to the composition of fatty bodies generally ; and it is to a clear comprehension of these, and of the bearing of other scientific facts and phenomena upon them, that are due the various manufacturing processes which have resulted in the elegant and useful commercial products called " candles," the varieties of which range from the softest and cheapest English " cottage composite," to the alabaster-like stearic acid " bougie" of the continental salons. It will be desirable, therefore, to consider the important fact, demonstrated by Chevreul, that all the ordinary neutral fats of commerce are, chemically speaking, " salts," in which the base is glycerine, and the acid is a mixture of various fatty-acids, which may be separated from each other, and prepared in a greateror less degree of purity. Hence Salt Acid + Base Neutral fat (e.g. tallow) = stearic and oleic acids + glycerine, C S H S (OH) 3 The fatty-acids of commercial solid fats belong chiefly to the series known as the " Adipic," of which Formic acid, CH 2 O 2 , and Acetic acid, C 2 H 4 O 2 , are the lowest terms. The two members of most frequent occurrence are Stearic acid, C^HjgO^ which is a large constituent of tallow, and Palmitic acid, C, 6 H 32 O 2 , which occurs in similarly large proportions in palm oil. Beeswax (to be referred to again presently) contains one of the highest known members of the series, Cerotic acid, C 27 H 54 O 2 . The fatty-acid of the fluid constituents of most natural fats, and especially of the non- drying oils, is called Oleic acid, C 18 H 3 ,O 2 , and belongs to another series, known as the "Acrylic." Each of the above-mentioned fatty-acids is capable of forming three salts with glycerine, the glycerides in natural fats being the third term in each series, tallow, for example, being a mixture of tri-stearine and tri-oleine. Chevreul's researches materially assisted in developing the theory of " Saponification " ; but as this will be fully discussed in the article on " Soap," it need not be alluded to here, further than is necessary to explain the principles of the process by which stearic acid was at first entirely, and is still very largely, manufactured. When neutral fats are boiled in open vessels, with a solution of a strong caustic alkali, as soda, or with lime mechanically suspended in water in a thin cream, the glycerine is replaced by the alkali, and a salt or soap is formed by the union of the fatty-acids with the alkali, thus : Neutral fat + Alkali = (Fatty acids + Alkali) i. e. " Soap" -f Glycerine. When the " soap" is dissolved in water, and a strong mineral acid is added to the solution, th fatty-acid is liberated Soap + Sulphuric acid = Fatty acids + Sulphate of soda (or lime). 2 P 2 580 CAKDLES. As neither saponification, nor the decomposition of a soap by a stronger acid, in order to liberate its fatty-acids, can take place except in the presence of water, the elements of water H 2 O play a very prominent part in all reactions relating to neutral fats, and the preparation of soaps and fatty-acids from them. It was soon discovered by Chevreul and his collaborateurs that the removal of glycerine from natural fats, i. e. their conversion into fatty-acids, enormously increased their hardness and illumi- nating power, so that candles made from the mixture of stearic and oleic acids, resulting from the removal of glycerine from tallow, by the process indicated above, were less greasy, and gave much more light, than candles made from the same tallow untreated, though they had not so nice a colour. The next step was the separation of the harder from the softer portions of the fatty- acids, and it was found that when this was effected by pressure, the oleic acid, in flowing away, carried with it in solution the whole of the colouring matter of the mass, leaving the crude stearic acid tolerably white. To make it absolutely so, little else was found necessary than repeated pressings at various temperatures, the series of operations, after the removal of the glycerine, being purely mechanical. In carrying out this on a manufacturing scale, the expensive alkalies soda and potash were soon replaced by lime, and the preparation of stearic acid by this process is now conducted as follows : The tallow to be purified is placed in a large, slightly conical, wooden tun, which will be more particularly described hereafter. In this tun, the tallow is mixed with 16 per cent, of good slaked lime, made into a thin cream witli water. After tightly closing the tun, steam is introduced from a pipe below, and the contents are boiled for four hours. During the boiling, the mixture is kept constantly agitated by means of a wooden shaft bearing three horizontal arms, worked by steam power. The action of lime upon the constituents of tallow has the effect of decomposing them, glycerine being set at liberty, while stearate, and oleate, of lime are formed. The formation of these salts, which, when mixed together, constitute an insoluble soap, greatly facilitates the subsequent separation of the solid and liquid constituents of the tallow. To ascertain when the operation is complete, a small portion of the boiling mixture is drawn out in a ladle, and cooled. When cold, the sample should appear perfectly smooth and solid, and should be very brittle, powdering finely in a mortar. When the operation is complete, the steam is shut off and the agitator is stopped, the whole contents standing until cool, and the fatty matters and lime form a solid mass at the bottom. They are then dug out and removed to another tun, similar in all respects to the last. Here they are treated with four parts of strong sulphuric acid for every three parts of lime previously added, and are then heated and agitated in the same manner as before. During the operation, the lime salts are decomposed by the acid, sulphate of lime falling to the bottom, and the soapy fat rising in a thick layer to the surface. Again, the whole is permitted to stand ; when cool, the fat is skimmed off and placed in a third wooden vessel, where it is well washed with water and by steam blown into it. The washed fat is next heated to the melting-point, and run into dishes or troughs made of tin ; these are placed in a room, the tem- perature of which is kept at from 20 to 30 (68 to 86 F.), and left for two or three days, or until the contents have assumed a granular or crystalline structure, when they are removed from the dishes, and cut into shreds by machinery. The shreds are then placed in canvas or woollen bags, or between large, square sheets of canvas, and are carefully deposited between the plates of a powerful hydraulic press. Pressure is exerted gently at first, and is gradually increased until the flow of the liquid oleic acid ceases. The press is then unlocked, and the hard, thin cakes of crude stearic acid are thrown into another wooden tun similar to the others. Here they are melted down by blowing in steam, which is continued for some hours. After settling, the fatty matters are drawn off into tin dishes, and placed aside to cool. The temperature of the room in which the cooling is conducted should be slightly higher than the previous one, or about 30 (86 F.). The dishes should remain here until the contents assume a crystalline structure, when they may be emptied. The blocks are then cut up into lumps, and ground to a mealy powder by means of a rasping machine, worked usually by steam. This powder is gathered into bngs, made either of hair or of wool, or both, and is then submitted to a second pressure in another hydraulic press, differing from the former one by having a heating apparatus attached ; the plates should also be heated before the press is used. The necessity for heat in this second pressure is due to the extreme difficulty experienced in eliminating the last portions of oily matter from the fat. When the full pressure is being exerted, the press is left for about fifteen minutes before being unlocked. The cakes thus obtained are cleaned with a knife, the parings being added to the next batch. They are again melted by steam, a little wax being sometimes added, in order to destroy the crystalline texture of the stearic ncid, which renders it unfit for use in candle-making. This finishes the process, and the steariue is melted into blocks ready for use. The tun in which the saponification of the tallow takes place is made of oak or cedar, and is tightly bound with iron hoops. Steam is introduced by means of a spiral copper tube, laid on the bottom, and perforated with numerous small holes. An upright wooden shaft, carrying wooden arms fitted with teeth, is fixed in the centre of the tun, and revolves during the process. The CANDLES. 581 tuns are arranged in rows in a large room, two being required for the completion of each batch. It will be observed that in this process a very large amount of lime 16 per cent, on the weight of tallow employed is used. The disadvantage of this is that much sulphuric acid is necessary to decompose the lime soap, thereby injuring the colour of the resulting fatty-acids. It was soon found that if the saponification were conducted in closed vessels, under a steam pressure of 3 or 4 atmospheres, the amount of lime might be reduced to about 3 or 4 per cent, upon the tallow, thus reducing the cost, and improving the colour, of the product. This modification is still very largely worked, especially in America. Subsequently it was discovered that if sufficiently high tempera- ture and pressure were employed, the lime might be dispensed with altogether, and that the resolu- tion of the fat into fatty-acids and glycerine might be effected by steam alone. This process, known as the " Autoclave," has been largely worked, both in Europe and America ; but in consequence of numerous accidents, arising from the explosion of improperly constructed vessels, it is usual to decompose tallow at a lower pressure, with the aid of 2 or 3 per cent, of lime, the subsequent opera- tions of crystallization of the fatty-acids, hot and cold pressing, &c., remaining the same. The next advance was the discovery that when neutral fats are exposed to a very high tempera- ttfre, 300 (572 F.), or above, in presence of superheated steam, they are decomposed, and the fatty- acids are volatilized ; and that when these vapours are condensed, the fatty-acids are almost white : that, in fact, fatty-acids may be distilled, almost unchanged, in an atmosphere of superheated steam. It was impossible, however, to conduct this process on a large scale, in consequence of the simul- taneous production of acroleine, a vapour resulting from the decomposition of glycerine, and possess- ing intensely irritating properties ; but, in 1841, it was discovered that if neutral fats were treated first with concentrated sulphuric acid, and then boiled with water, they might be distilled without any such inconvenience, and the problem was thus solved by Dubrunfaut. In 1842 and 1843, Messrs. Jones and Wilson, under the name of Price and Co., took out two patents for the combined treatment of fatty bodies by sulphuric acid and water successively, and their subsequent distillation by the aid of superheated steam. From that time to the present, this process has been worked, in its various modifications, on a most extended scale, especially in England. It gives a much larger quantity of material, of good colour for candle-making, from a given weight of fat, than any other known process. The candles are not so hard, nor quite so white, as the continental boitgies of stearic acid ; but while tallow, treated by the saponification process, yields only about one-half its weight of candle material, tallow and palm oil, when distilled, give at least 75 per cent, of such material, of a slightly inferior quality. The most perfected form of apparatus now used hi the distillation process, as made by Merryweather and Sons, Long Acre, London, is shown in Fig. 463. The process is conducted as follows: The fat is melted from the casks in which it is stored, by means of a steam jet inserted in the bunghole, and runs into the underground wooden tank A, where it is left for some hours to settle the condensed water out of it. Hence it is pumped, by means of the gun-metal lift and force- pump C, into a series of lead-lined collecting tanks B, fitted with steam coils, by which the material is boiled before being passed through the tap c to the vessel D. This latter, which is known as ths " Acidifier," is made of stout copper, supported either on wrought-iron girders or on brickwork. It is fitted with a valved pipe a, for the admission of superheated steam; a copper pipe fitted with water shower pipe d, for condensing the vapours generated by the acidifying process ; a thermometer b, for guidance as to temperature ; and a gun-mefeil cover e, at the lower side, for cleaning out, and to which is affixed a tap /, for drawing off the acidified materials. On admission to D, the fats are heated for a certain time, by the introduction of superheated steam at a temperature of about 176 CANDLES. (350 F.), from the superheater F, constructed from the special design of Ed. Field. Sulphuric acid, in the proportion of from 3 to 6 Ib. per cwt. of fat, is next supplied to the acidifier from the tank E by opening the plug g. When the acidification is complete, the material is left to stand for about six hours, and is then discharged into a series of lead-lined, open washing-vats G, provided with copper steam coils, and containing water and a little sulphuric acid. Here it is boiled with free steam for another two hours, and is left for about twenty-four hours to settle ; it is then drawn off into the tank A, and pumped through the tap c' into a large, open, lead-lined tank H, placed at a sufficient elevation. This tank is fitted inside with a coil, which is charged with steam, to keep the contents in a liquid state. By means of the valve A, about 5 tons of the material is run into the still I, consisting of an iron body, and copper dome ; it is fitted with a thermometer ', and the necessary taps of copper or gun-metal. The contents of the still are heated, by fire, to a temperature of about 116 (240 F.) ; superheated steam, at about 294 (560 F.), is then admitted by the pipe m from the superheater N, and the process of distillation commences. The temperature must be regulated according to the quality of the material operated upon. The vapours pass over by the pipe n to the refrigerator K, which consists of a series of vertical copper pipes, connected at top and bottom by gun-metal bends. These pipes are mounted on iron frames, over a set of six circular iron tanks k, into which they can be emptied. The tanks are furnished with pipes for the admission of steam, and with spiral copper cooling-coils, through which cold water may be passed. The "essence-tank" / is fitted with an improved shower-pipe L, which prevents any vapour passing away uncondensed. The pipe M conveys vapours to be burnt in the flue. The fatty-acids are collected in pails from the mouths or outlets of the copper coils, the greater part in a fit state for candle-making, without the necessity for putting them through hydraulic presses. That part which is not fit for candle-making, as it comes direct from the still, is pressed and redistilled. As the result of distilling t dlow, it may be mentioned that out of every 100 Ib. subjected to this process, 78 to 80 Ib. of crude stearic acid is produced. Three-fourths of this, or about 60 Ib., is ready for making stearine (i. e. stearic acid) candles without further treat- ment ; the remaining fourth, about 20 Ib., after being pressed and redistilled, yields about three- fourths of stearic acid and one-fourth of oleic acid. Thus the total proportion of the latter product is only 5 Ib. Besides the stearic and oleic acids, there is a large quantity of a third product, called " pitch." If allowed to get cold, this is a hard, black substance ; but provision is made for passing it at once to an iron vessel, where it is submitted to great heat, and yields a product similar to that obtained by the distillation process, and which is often used in the preparation of " composite " candles, though much inferior to the pressed and purified material. The pitch, after this operation, becomes a commercial article of many uses, and will in all probability soon be recognized as an efficient substitute for "black-japan," for coating iron, the latter article being worth from 20s. to 30s. a gallon. The approximate cost of the plant required for distilling tallow or palm oil according to the above process, exclusive of steam boiler, may be stated at from 1700/. to 3150/., according to whether 1 ton or 3 tons are to be distilled at a time. The following table shows the quantity and value of tallow and stearine imported to this country in the year 1878 : (N.B. Stearine, chemically speaking, i.e. stearate of glycerine, is seldom or never made now, and the term "stearine" is somewhat loosely applied, commercially, to stearic or palmitic acids in various states of purity.) Cwt. 73,646 158,480 France 14 810 42 760 456,715 873,696 63 587 124 054 Argentine Republic 66,754 216 786 134,765 419 268 Other countries 28,905 61,156 921,203 1,814,179 The total quantities and values for the four preceding years were as follows :- 1874. 1875. 1876. 1877. cwt. 1,155,243 cwt. 967,396 1,344,445 cwt. 1,224,239 2,331,479 2,045,863 2,875,170 2,568,479 CANDLES. 583 Palm Oils. Palm oil is now used in enormous quantities for the production of palmitic and Btearic acids at Price's Candle Company's works, as well as by almost every candle manufacturer in Great Britain, about 25,000 tons being annually consumed. In many continental countries, a prohibitive duty prevents its employment. The process employed consists in acting upon the fat with sulphuric acid, and then submitting it to distillation. The plant and the modus operandi scarcely differ from those last described. The distilled mixture of stearic and palmitic acids is cut into shreds, by means of a revolving knife, and the shreds are wrapped in canvas or woollen cloths, spread in even layers between mats of cocoa-nut fibre, and submitted first to the cold press, and afterwards to the hot press, at a temperature of 29 to 32 (85 to 90 F.). The pressed cakes of fat are pared, and then melted again by steam, in large, wooden, iron-bound vessels, containing water and sulphuric acid. The whole is boiled for a time and is then allowed to Btand, after which the acidulated water is drawn off. The melted fat is repeatedly washed with hot. water, and then run into moulds ; when cold, it is quite pure, and ready for manufacture into caudles. It will be observed that three processes for the decomposition of neutral fats have now been described viz. (1) By saponification with a strong alkali, at a temperature but little above 100 (212 F.) ; (2) By the use of water, with or without a very small quantity of lime, at very great steam pressure, and a correspondingly high temperature; (3) By treatment with strong sulphuric acid and water in successive portions, and subsequent distillation at normal atmospheric pressure, but at a dangerously high temperature above 300 (572 F.) It was reserved for a physician at the Danish Court, the late Dr. J. C. A. Bock, to demonstrate the important fact that, by properly conducting the operation, water alone might be made to decompose tallow into fatty acids and glycerine, and that by the use of water and sulphuric acid combined, fatty-acids might be prepared from tallow in open lead, lined tanks furnished with steam coils, without any of the complicated and dangerous apparatus required by the " autoclave " or the " distillation " processes, without any lime or other alkali, and with a much less expenditure of acid than was required by any other process. Unlike many inven- tors, he was able to carry out his ideas into actual practice, and in the International Exhibition held in London in 1862, were shown some beautifully white and hard stearic acid candles, which had been prepared by this process in the manufactory of O. F. Asp, Prindsessegade, Copenhagen. Since then, the process has been constantly at work in that factory ; it has also been adopted in several other continental candle factories,"and is now at work, among other places, in New Zealand. The simple character of the " plant " required renders it peculiarly valuable for distant countries. Considered from a theoretical point of view, it is, perhaps, the most ingenious and the most strictly scientific of all the methods for decomposing neutral fats. Dr. Bock pointed out, that tallow is composed of exceedingly minute globules of fat, surrounded by membranous envelopes, composed, probably, of albumen ; and that until these enveloping walls are destroyed, no reagent can act upon the fat within. In ordinary saponification, the albuminous envelopes are dissolved by the caustic alkali ; in acidification, they are burnt and charred by the strong sulphuric acid, the quantity of which may be so adjusted as not to burn and discolour the tallow itself, which, after pouring out from the destroyed envelopes, is in a state to be readily decom- posed by water at 100 (212 F.). Dr. Bock's process was described by him in an article in Dingier ' ' Polytechnisches Journal,' for May, 1873, of which the following is a synopsis. " By the lime saponification plan, the albumen contained in the fat is dissolved, lime-soap is formed, and the extraction of the glycerine is rendered possible. By acidification, the whole pro- cess is affected at once. Conducted properly, the fat, washed out with water, always remains as neutral fat, and, by the use of concentrated sulphuric acid, not a trace of glycerine is left. Acidi- fication, rationally conducted, is only a preliminary operation, intended to break up, corrode, or carbonize, the albumeniferous matters. But the conduct of the operation was long based on the erroneous belief that a double acid, sulpho-stearic, was formed. With due care, only the envelopes of the cell-< are blackened, and these are soluble neither in fat nor in fatty acids. The production of a real black solution is only an evidence that a certain part of the fat has been burnt which should be avoided under all circumstances. There is no doubt that the operation has generally been carried to excess, in the matters of duration, height of temperature, or strength of acid. By proper acidifi- cation, the neutral fat is only unclothed, as it were, and freed from the cells, or at any rate, the latter are so ruptured, as to allow of the easy exit of the fat. This latter is then in a condition to be decomposed, an operation accomplished in much shorter time by the chemical equivalent of acid 4 to 4-5 per cent. and the necessary water. After letting out the glycerine waters, the fatty-acids appear more or less black. They may now be distilled. Their melting-point varies from 49 to 57 (120 to! 34 F.). " The real value of Dr. Bock's method consists in dispensing with distillation. The object of this operation is the removal of the black colour, or rather of the black- coloured matters, by superheated eteam. These black matters are the partially carbonized albumen cells, which swim about in the fatty-acids because the sp. gr. of the two bodies is about the same. This difficulty is overcome 584 CANDLES. by oxidizing the mass, by which the sp. gr. of the cells is raised from 0'9 to 1-3. They are t' us precipitated, and the fatty matters can be washed off. The subsequent cold and hot pressing are the same as with ordinary methods. " From several years' experience at Messrs. Asp's works, the following results have been deduced. Tallow yields, by complete decomposition, 95 per cent, of fatty-acids, which lose 2 per cent, by oxidation and washing. The glycerine obtained equals 6f per cent, from tallow at 23 B., and is quite free from all organic acids. The oleic acid resembles that produced by the lime saponification process ; but it is much richer in solid acid. The stearic acid is also like that produced by the lime saponification method ; but it is much harder, and its melting-point is 5S-60 (136-140 F.). It equals 55-60 per cent, of the tallow employed. " The plan is free from danger, as the steam is only used in open vessels. The plant is much cheaper, as nothing special is required. The labour also is much reduced, as the operation is com- pleted in one vessel. It is as applicable to vegetable as to animal fats." The process indicated above has now been for fourteen years in daily operation on a manufac- turing scale in Copenhagen, and in the hands of the inventor and his son, has been greatly im- proved and simplified since its first introduction. At that time, there were five stages in the process, viz. : (1) Acidification, to remove the membranous cellular tissue from the tallow ; (2) Decompo- sition, by acidulated water, into dark fatty-acids and glycerine; (3) Oxidation, to increase the sp. gr. of the dark membranous matters, so that they might separate themselves from the fatty-acids ; (4) Repeated washings with water ; (5) Pressing, both cold and hot. The greatest improvement is due to the discovery that the dark membranous matters may be oxidized while the fat is still neutral. The acidification, oxidation, and decomposition are all now conducted, in rapid succession, in one and the same wooden tank, after which, one or two washings in another tank render the fatty-acids fit for the press. Another point of great practical importance, which has been developed in the working out of this process, is the increased hardness of the stearic acid produced by it, arising from the solidifica- tion of some of the oleic acid in the tallow, by the prolonged action of sulphuric acid upon it. This reaction has lately been pointed out as a novelty, by Bornemann and Kraut ; but it was suspected twelve years ago, and soon afterwards was definitely proved, by the Messrs. Bock. They observed that the fatty-acids became harder and harder, so that cold pressure had no effect upon them ; by the adoption of hot-pressing, they produced white stearic acid, and an exceedingly brown oil. This latter, when distilled, saved the cost of distillation, by its yield of solid matters. It is claimed, therefore, for the Bock process, that stearic acid can be made of better quality and in larger quan- tity from a given weight of tallow, than by any other process at present known. Whichever of the four processes (lime-saponification, autoclave, distillation, or Bock's) is employed, a large proportion of oleic acid is unavoidably produced. The quantity of it, per ton of neutral fat, varies in inverse proportion to the hardness of the original fat, or of the material manu- factured from that fat. For many years, it was difficult, at any rate in England, where soft soaps are much less used than on the Continent, to find a suitable outlet for this oleic acid : it could not be used as a lubricant, owing to its acid reaction upon metals ; when saponified by the ordinary methods, it produced a very soft and very brown soap, slow of sale. It was discovered, however, that when saponified with soda-leys of very high specific gravity, a hard soap could be made from it, containing a very large percentage of fatty-acids, and good for ordinary cleansing purposes, but whose smell was considered objectionable. A few years ago, M. Eadisson, of Lyons, taking advantage of a laboratory reaction of oleic acid which had long been known, developed a method of converting it into palmitic acid, and, by dint of great perseverance, worked out the details of the process on an industrial scale ; it is now a commercial success, and has been patented in nearly all countries where candles are manufactured. Whether it is more economical to convert the oleic acid into soap or into palmitic acid, depends upon the relative cost of the two processes, and the current market value of the manufactured products. The following information relative to this remarkable process, which is extremely interesting, from both scientific and technological points of view, was kindly supplied to the writer, by the patentee, M. St. Cyr Kadisson, 37, Boulevard-Oddo, Marseilles. In 1841, Warentrapp announced that when oleic acid was heated with a great excess of caustic potash, it was decomposed into palmitic acid, acetic acid, and hydrogen, the acids combining with the potash, the reaction being explained by the following formula : Olficacid. Potash. Palmitate of Potash. Acetate of Potash. Hydrogen. C 18 H, 4 2 + 2KHO = C.^KO, + C 2 H 3 K0 2 + H 3 . At M. Radisson's factory at Marseilles, this is practically realized, and about 3 tons of oleic acid are daily converted into palmitic acid, by this process. The conversion is effected in cylindrical cast-iron vessels, with sheet-iron covers ; they arc about 12 ft. in diameter and 5 ft. high. A fireplace is built beneath them, sufficiently far off to avoid heating by radiation. About 1 J ton of oleic acid and 2} tons of caustic potash leys at 43 B. are CANDLES. 585 pumped into one of the vessels. The evolved steam passes off by a large manhole on the upper side; when the soap gets dry, this manhole is closed, and the disengaged gases are conveyed through pipes, first to a condensing tower, and thence to a gasometer. The temperature of the mass is slowly raised to 320 (608 F.). A mechanical agitator revolves in the mass, with the double purpose of ensuring equal distribution of heat, and of beating down the froth, which rises abund- antly. Eventually the soap undergoes igneous fusion, and at 290 (554 F.), begins to give off hydrogen. When 320 (608 F.) is attained, the escaping gases have a peculiar smell, very readily recognized ; at this point, it is necessary to suddenly stop the operation, since if the heat were continued longer, the materials would enter on the stage of " destructive distillation." In order to effect this stoppage, steam and water are introduced by a Giffard's injector, and at the same time, a door in the bottom of the cylinder is opened, by which the palmitate of potash falls into an open tank, where the soap and a quantity of water sufficient to melt it, are heated together by a steam- jet. After subsidence, the contents of the tank divide themselves into an upper layer of ntut.'al palmitate of potash, and a lower layer of potash leys, usually about 18 B. The neutral palmitate is removed to another vessel, and decomposed with sulphuric acid ; the last traces of sulphate of potash are removed by washing with water. At this stage, the palmitic acid is of a clear chocolate hue, and when cooled, crystallizes in large tables; its solidification point varies between 50 and 53 (122 and 127 F.), according to the nature of the oleines employed. It can be distilled with great facility in the usual apparatus, and leaves only 3 per cent, of pitch. After distillation, the palmitic acid is extremely white, and burns with a very clear, smokeless flame. Moulded into candles, it compares very favourably with the best stearic acid ; and when mixed with ordinary stearic acid, it " breaks the grain " of the latter (i. e. destroys its tendency to crystallize), and gives it a semi-transparency, very valuable in the eyes of a candle manufacturer. Instead of decomposing the palmitate of potash by sulphuric acid, it may be boiled with milk of lime, under a pressure of three atmospheres, when the result will be a lime-soap, floating in caustic potash leys. So much water, however, is necessary for this reaction, that the resulting leys are only 6 B., and their concentration to 43 B. is so costly, that it is more economical to regenerate the sulphate of potash by Leblanc's process. The potash leys may be completely causticized in the cold at a sp. gr. of 20 B. with six hours' brisk agitation, thus economizing fuel. The carbonate of lime so obtained is pulverulent, and can be easily washed by " displacement " (i. e. running water through it to wash out the potash), in a layer 3 ft. thick The caustic leys are rapidly con- centrated to 43 B., and stored in tanks, where, on cooling, they deposit the small amounts of sulphate and carbonate of potash which they contain, and the vertical partitions of the tanks become covered with crystals of acetate of potash, arising from the preceding solidification. The perfectly clear leys are then employed in the transformation of fresh portions of oleic acid into palmitic acid. The crystals of acetate of potash are separated from the leys which hang about them, by a centrifugal machine, and are then taken to a distilling apparatus, where the acetic acid is displaced by sulphuric acid. The crude acetic acid, thus obtained, is purified by a second distillation, and becomes of commercial value. Its quantity should be 2' 5 per cent of the oil solidified. Oleic ac-id, which is the product of the distillation of fatty bodies, contains small quantities of hydrocarbons analogous to natural petroleum. These distil over during the conversion of oleate of potash into palmitate, and are condensed in a tower, furnished with transverse partitions, extending alternately nearly across its diameter. A simple rectification makes them pure enough for illuminating oils, and the paraffin which remains in the heavy portions of the oil can be separated by crystallization in the cold. As a matter of purely scientific interest, it may be mentioned that caprylic alcohol, sebacic acid, caproic acid, and other rare substances, are formed, in very small quantities, simultaneously with the palmitic acid. All fatty bodies, with the exception of mare's grease, and the fat of " suint," can thus be solidified by the action of caustic potash ; but the ultimate products vary, and the palmitic acid ia by no means always pure. Different percentages of palmitic acid are obtained in the final result, according to the nature of the fatty bodies employed. Thus, 100 Ib. of oleic acid, resulting from tallows decomposed by lime, should yield 91 Ib. of palmitic acid fit for candle-making, while 100 Ib. oleic acid resulting from distillation processes, only yields 87 Ib. of white palmitic acid. The following figures give the cost, in francs per 100 kilos., of white palmitic acid produced from distilled oleic acid : General charges 5 -80 Labour 6-35 Loss of alkalies 2'60 Fuel for all operations 8 '10 Carbonate of lime 0'60 Caustic lime , .. 0'65 Sulphuric acid 2 CO Wear and tear of plant .. .. '95 Distillation 3-50 31-15 or a total of about 13/. a ton. 536 CANDLES. It is not necessary to describe here all the difficulties encountered in obtaining, by the Leblanc process, an economical transformation of sulphate of potash into caustic. It may, however, be mentioned that an evaporating pan, placed at the back of the furnace on a level with its bed, has been found most useful. It is fed by the mother-liquor of the sulphate of potash, which, by its evaporation, keeps up a supply of moisture arouud the small particles of potash, which are volatilized, or carried over mechanically by the furnace draught, and thus, by increasing their density, causes them to settle in the pan. This simple contrivance has so reduced the loss of potash as to render possible the application of the Leblanc process. M. Radisson claims the following advantages, as accruing to the stearic acid manufacturer from the adoption of his process : 1. Utilization of the oleine, a troublesome by-product of variable value ; 2. The floating capital necessary for the purchase of raw material is diminished by about 30 per cent., the production of stearine being increased by nearly the amount of oleine produced ; 3. The manufacturer can use low-priced greases, whose value varies in inverse proportion to their richness in oleine ; 4. The stearine produced by this process is little, if at all. inferior to that produced by any other process. It may be noted as an interesting fact, that the oleic acid produced by Bock's process is more suitable for conversion into palmitic acid than that produced by either of the other methods. The two processes (Bock's and Radisson's) are worked conjointly with the most satisfactory results. The percentage of palmitic acid from Bock's oleic acid, is higher than that from any other. Wax. Beeswax is a product of no small importance for candle-making purposes. A trifling proportion only is made in England, but it is of far superior quality to the produce of other lands. A considerable quantity is imported annually from Corsica, and smaller amounts from India, Ceylon, North America, and Brazil. Beeswax is always of a brownish or yellowish colour, and has a peculiar smell resembling, and derived from, honey. It is purified and rendered white by being melted in hot water, or by steam, in a vessel either of tinned copper or of wood. It is allowed to settle, and the waxy superstratum is run off while fluid into a wooden trough, having a row of perforations in its bottom, by which it is distributed upon horizontal wooden cylinders, made to revolve with their lower portions surrounded by cold water. The ribbons or films made in this way are then exposed to the bleaching action of the atmosphere and sunlight, being frequently moistened and turned over during the process. It is necessary to guard against wind, which might scatter the shreds; for this purpose, large cloths are provided. The operation is continued until the wax becomes perfectly clean and white. It is usually conducted from April till September, the exigencies of the weather preventing it at other seasons. In France, it is customary to add a little cream of tartar or alum to the water in which the wax is melted, by which the long and tedious operation of bleaching is rendered unnecessary, or much shorter. Bleaching agents, such as chlorine, cannot be employed to bleach wax, since they render it unfit for making into candles. Purified in the above manner, beeswax is perfectly white, and has neither taste nor smell; it has a specific gravity of from 0-960 to 0-996; at a temperature of 30 (86 F.) it becomes soft, and melts at 68 (154 F.) ; at (32 F.), it is hard and brittle. Other kinds of wax are also used, such as Chinese wax, derived from an insect, the Coccus ceriferus ; Japan wax, of vegetable origin ; Carnauba wax, from Rio de Janeiro, which is also a vegetable wax, remarkable and especially valuable on account of its high fusing-point ; and several other varieties of vegetable wax, derived, like the last two, from palms. Besides these, may be named the greenish Myrica, or myrtle wax, obtained from the fruit of the Myrica cerifera. It is used in America for candle-making. "Wax candles are superior to tallow candles, not merely on the score of hardness, elegance, and cleanliness, but also on account of the greater purity and bril- liancy of their light. Paraffin. During the last twenty years, paraffin has come largely into use for candle-making. The crude solid product separated from the light and heavy oils by the mineral oil refiners, and known as " paraffin scales," is of somewhat variable composition. The impurities amount, on an average, to 20 per cent, of the weight, and consist of blue oil, greasy hydrocarbons of low fusing-point, solid refuse, and water. The oil manufacturers, having an eye to the quantity of solid product, often separate the scales from the oil, as early in the process of oil refining as possible, knowing that the subsequent distillation and the treatment with acid and alkali will reduce the weight of solids by decomposition. Hence the process of refining may vary according to circumstances. The method adopted by Messrs. Young and by Wm. Walls and Co., of Glasgow, is first to melt the scales in a large pan, by the introduction of steam through a perforated wrought-iron coil. The mechanical impurities and the bulk of the water subside ; the supernatant liquid is decanted into another vessel, and mixed with a due proportion of coal oil or spirit, varying in gravity from 0'735 to 0-765. It is then caked, or allowed to fall on a revolving drum, kept cold by an internal flow of water ; less oil or spirit say J of the weight of the scales is required by the former plan, more by the latter. The cakes or pulp, as the case may be, are then placed between porous or absorbent materials, usually cocoa-nut matting lined with canvas. These are arranged in a CANDLES. 587 hydraulic press, fitted with iron plates and wickerwork mats to keep the layers distinct, and are subjected to pressure. This operation is repeated till all the oil and greasy hydrocarbons are removed. When this is accomplished, the cakes, as removed from the press, should be almost transparent. Instead of employing clean coal oil or spirit at each operation, some manufacturers, with a view of economy, use the pure liquid for the last wash only. When this principle is adopted, the liquid pressed from the cakes at the last operation is used for those at the second stage, and from that stage again for those at the first stage. Thus the scales are subjected to three pressings, which, if done with care, should be sufficient to pro- duce highly refined paraffin. It is obvious, however, that unless the scales have been properly treated by the oil refiners, before coming under the operations described, disappointment and failure will result. It is also clear that the refining will be more perfect by using pure spirit at each operation. The oldest form of hydraulic press was the ver- tical cold press, still used for the commoner kinds of fat. The newly introduced hot presses, on the other hand, are horizontal in shape, and altogether of superior construction. They are made by Needbam and Kite, of Vauxhall; and by Galabrun Freres, of Paris. Figs. 464, 465, and 466 show respectively a front elevation, partly in section, side elevation, partly in section, and a plan, of a novel hot press specially adapted to the requirements of paraffin, sperm, and stearine refiners. It is made by James Clarkson and Co., Maryhill Engine Works, Glasgow, from the design of W. Walls, Esq., of that city, through whose kindness the following description and illustrations have been obtained. For convenience in working, and economy of labour, whether as a hot or as a cold press, it is '/ // \^. ^ o) 588 CANDLES. unequalled. The plates A are notched at each end with a check of varying width, corresponding with the diameter of two vertically tapered bars B, placed at each end of the press and parallel with its supporting pillars. The object of this contrivance is to do away with the necessity for a balance weight, or other arrangement for bringing back the ram, plates, &c., when the press is opened. By this plan, on the ram being lowered by its own weight, each plate falls back into place, being stopped by the increasing size of the tapered bars ; thus the plates are held in their places, equi- distant from each other, and in a position to render the refilling of the press a matter of the greatest ease and simplicity. The bottom of the press ia cast with a trough on it, which receives all the drippings from the plates, while the cylinder head, and the bottom collars on the pillars, are pro- vided with projecting drooping rings ; in this way, no oil can escape down the sides of the tapered bars or the pillars, but all must drop into the trough. The press is entirely encased in sheet iron, with hinged doors in front, for introducing and withdrawing the materials. A perforated steam pipe G is introduced at the top of the press, and is carried down the back inside ; thence it passes on both hands around the bottom of the trough, for the purpose of keeping the drippings in a liquid state. An outlet pipe is attached to the front or back of the trough, and serves to conduct the oil to a tank. The process of purification is simply mechanical ; its efficacy, other things being equal, may be a subject of arithmetical calculation, the factors being the relative quantity of spirit or oil used at each wash, the amount of oil left in at each pressure, and the number of washes. There is, moreover, another matter which exercises an important bearing upon the results, viz. the tempera- ture at which the cakes are cooled after each melting. In the act of cooling, crystallization takes place, and the slower this is performed the more perfect are the crystals. The result is that when a perfectly crystallized cake is subjected to pressure, it behaves like a sponge, yielding up the impurities to combination with the spirit. A quickly cooled cake, on the other hand, may be compared to a piece of putty or dough, and will not press to advantage, nor yield satis- factory results. The washes containing the impurities, along with paraffin in solution, are, as haa been shown, either sent back in the process in bulk, or the naphtha may be distilled off, and the residue returned and treated ab initio. In all cases, the liquid which has been used for the washing at the first stage is the most heavily charged with low hydrocarbons, and must be subjected to distillation. The spirit is separated from this residue by steam heat, and may be uaad again ; but the heavier portions require treatment with acid and alkali, as in the case of crude oils. The cakes, which, by repeated washing and pressing, have been freed from colour, and from the greasy constituents which would spontaneously decompose and injure the wax, will, even after extreme pressure in hydraulic, presses heated by steam, still contain a proportion of naphtha. To get rid of this, the cakes are put into a still or. rectifier, an iron vessel furnished with a condensing apparatus. Amongst the melted paraffin, high pressure steam is introduced through a perforated pipe, and produces violent agitation. This is continued till the last trace of smell ia removed, 12 to 70 hours being required to effect it, according to the specific weight of the oil or spirit used. The condenser is employed for the purpose of recovering the naphtha for future use. The only operation uow requiring explanation is the passing of the liquid wax through animal charcoal. Before this process can be applied with effect, every trace of suspended moisture must be removed ; this is done by heating the liquid, as decanted from the rectifier, in a steam-jacketed pan. After the complete removal of the water, freshly burned animal charcoal, to the amount of 5 to 8 per cent., is added to the wax, stirred actively for half an hour, and left to settle. The clear liquid is then allowed to percolate through filters, which effectually remove the very fine particles of charcoal that refuse to subside. This liquid, which should now be as pure as water, ia put into moulds to cool, when it will be ready for candle-making. By the method above described, the very finest " wax " is now made by the Glasgow firms before mentioned. The only drawbacks to this interesting process are the risk of fire, created by the accumulation of inflammable vapour of naphtha, and the loss of volatile materials from the same cause. To obviate these drawbacks, other methods of refining paraffin have been devised and duly patented by their inventors ; but no other process has proved effective in yielding a paraffin- wax of equal purity and beauty. The patent process adopted by Price's Candle Company, at Battersea, depends upon the fact that paraffins have different melting-points. Oil has a greater solvent power over the low paraffins, consequently when a properly crystallized cake is warmed to a degree below the fusing-point of its higher constituents, the lower grades melt, and carry away with them oil and other impurities, leaving the former comparatively pure and free from oil. The proportion of oil in these drainings is such that, when caked, they can be pressed without any addition of naphtha, and can thereafter be mixed with scales for draining again. This operation is performed in " cooking cupboards," closets about equal in size to an upright hydraulic press, fitted with shelves formed of double iron plates, each shelf being charged with steam. The hard, partially purified paraffin cakes, which remain on the shelves of the "cooking cupboard," are melted in a lead-lined vessel heated to 177 (350 F.) and into them is forced from 5 to 10 per cent, of CANDLES. 589 sulphuric acid, sp. gr. 1 845. Sulphurous fumes are copiously given off, and must be conveyed away by suitable means. The agitation with steam is kept up for several hours, and by this treat- ment, all the more unstable hydrocarbons are destroyed, and settle down in the tank. The contents are allowed to stand for a time; the paraffin is drawn off, treated with weak soda ley, then digested for a considerable period with animal charcoal, and passed through a filter, heated by a steam jacket to maintain the fluidity of the mass. Several materials have been substituted for charcoal in the above process. In one instance, the addition of about 12 per cent, of powdered fuller's earth, at a temperature of 110 (230 F.) is recommended. The mixture is well agitated, then left to settle, and the clear paraffin is run off. The fuller's earth may be cleansed from paraffin by washing or agitation, and used again. By another process, invented by Smith and Field, silicates of magnesia, and of other bases, may be employed for the same purpose. Pure paraffin is sometimes used alone for candle-making; but it is generally mixed with pro- portions of hard stearine, varying from 5 to 15 per cent. The refined paraffin causes the candle to burn with a flame of great power, while the high melting-point of the stearine renders it less liable to bend under the influence of a warm atmosphere, and to give off smoke during combustion. Spermaceti. The substance known as "spermaceti" is a valuable product for candle-making. The first operation needed to fit it for use is technically termed " bagging." The crude sperm oil, as brought in by the whalers, is placed in a reservoir, at the bottom of which are a number of pipes leading into long bags lined with linen, and temporarily closed at the bottom by tying cords round the mouths. The pressure exerted by the body of material in the reservoir forces a large proportion of the oil through the parts of the sacking, leaving behind the solid or " head-matter," as a dingy brown mass. This so-called crude or " bagged " sperm is deprived of a further quantity of oil by the application of pressure. It is put into hempen bai?s, which are deposited between the plates of a hydraulic press such as that shown above. The pressure applied is about 80 or 90 tons. When the oil ceases to flow, the sperm is taken out, melted by heat, and then drawn off into trays to granulate. The brittle crystallized blocks are ground to a coarse powder by means of revolving cylinders; the powder is collected in a bin beneath, and is filled into cloths, and subjected to a hydraulic pressure of about 200 tons. The oil expressed under this force contains a small amount of solid matters, and is therefore returned for re-bagging. The blocks, as turned out of the press, are melted down, and boiled for 2-3 hours with caustic soda ley of sp. gr. 1'IOD, in the proportion of 40 parts by measure of the former to 1 of the latter. It is important to guard against an excess of alkali beyond that required for combination with the oil, as it would tend to saponify the spermaceti, and cause a waste of material. The mixture is kept at a low, equable temperature, till the oil is taken up, aud is allowed to remain at a gentle simmer, while the soap that has been formed rises to the surface and is skimmed off. The heat is then raised to about 121 (250 F.), and the mass is treated with small successive doses of water, the additional scum being carefully taken off as it rises, till the whole is clear. It is then drawn off to crystallize in flat tin dishes, whereupon the cakes are again reduced to powder, placed in linen bags, and subjected to hot pressure in a very powerful hydraulic press heated by steam, after which the spermaceti will still contain a quantity of oil, or weak sperm, which no mere pressure will remove, and which must be extracted by saponification. The final operation consists in boiling down the sperm with strong alkaline ley at 112 (235 F.), removing the scum as before. When the latter ceases to appear, further purification is effected by introducing a little water, at intervals, while the heat is lowered. The supernatant spermaceti, now perfectly colourless and transparent, is cast into blocks and crystallized. Spermaceti candles are valued for their beauty and illuminating power. They usually contain about 3 per cent, of wax or paraffin, to counteract the crystalline structure of the spermaceti, and are moulded in the ordinary way. The addition of a little gamboge makes the spermaceti resemble wax, the compound being known as " transparent wax." fizokerit. From " ozokerit," or " earth wax," a kind of mineral paraffin, have long been fashioned crude miners' candles, in the districts where it is found; but the application of the sub- stance to the manufacture of candles suited to civilized needs is confined in England to one firm, Messrs. Field, of Lambeth. The colour of the mineral varies from brown to greenish and yellow tints; its fracture is resinous. It contains 85 '75 percent, of carbon, and 15-15 per cent, of hydrogen, and appears to consist of a group of hard, solid hydrocarbons, whose melting-points range from 60 to 80 (140 to 176 F.). Dr. Letheby says that the illuminating power of ozokerit exceeds that of the best paraffins, and is therefore far beyond those of spermaceti, wax, and stearine. The following table shows the number of grains of the various substances enumerated required to give the light of 1000 grains of the best spermaceti candles : Ozokerit 754 Paraffin 798891 Spermaceti .. .. .. 1000 Wax 1150 Various compounds ..9921189 Stearine . ..1200 590 CANDLES. The leading properties (i ozokerit are : (1) That it has a very high melting-point, and does not bend or soften in a warm atmosphere ; (2) that it has a great illuminating power ; (3) that it burns with a dry cup, and is not so liable to " gutter " as ordinary transparent candles ; (4) that it is entirely free from smell, is not at all greasy to the touch, and has an appearance closely resembling the finest bleached beeswax. The refining of ozokerit for the purposes of candle-making is almost identical with the processes, already described, for refining palm oil and paraffin. The mineral is first carefully distilled ; the product mixed with oil is submitted to powerful pressure, to remove the latter as much as possible, the extraction of the last traces requiring a treatment with sulphuric acid. The melted material is thoroughly washed, and repeatedly filtered through animal charcoal. When thus purified, the ozokerit resembles fine beeswax in colour, but is more translucent than wax, though less so than paraffin. The hardness and high melting-point of the candles made from this source give rise to a drawback, common to wax candles, viz. the smouldering of the wick on extinction. The immediate cause of this is the fact that the cup of the candle dries and solidifies as soon as the flame is blown out, so that there is no liquid matter left to extinguish the spark. This difficulty is now overcome by a special contrivance of the wick. WICKS. The next point for consideration is the wick, constituting the medium through which the combustion of the fatty or hydrocarbonaceous matter is performed. The chief essential qualities of a wick are good power of absorption, and a capacity for burning freely, evenly, and thoroughly, while producing the least possible proportion of ash. It must necessarily be quite free from inequalities of whatever kind, and should be made of perfectly sound fibres. The forms and kinds of wick differ widely with the quality and composition of the candle ; the melting-points, and other characteristics of the hydrocarbonaceous bodies forming the caudle, vary to such an extent that, in order to burn to the best advantage or indeed, in some cases, to burn at all each sort of candle needs to be accommodated with a special wick. One of the greatest secrets of candle-making is to have the wick perfectly suited to the peculiarities of the fatty matters employed ; on this score, it is impossible here to do more than indicate the principles involved. But little variety is to be remarked in the choice of material for making wicks. The original, and not yet obsolete, medium was the common soft rush, Juncus conglomerate, to be found in most moist pastures, and by the sides of streams and ditches. They are in best condition in the height of summer, but may be gathered on to the autumn. As soon as cut, they are placed in water, other- wise they would dry and shrink, and the peel would not run. They are then stripped of half the peel, the object of which is to expose the pith sufficiently to enable it to conduct the molten fat, while enough of the rigid epidermis remains to afford it support. When duly peeled, they are laid out to bleach and take the dew for some nights, and are afterwards dried in the sun. These rushes are gathered in Lancashire, and abundantly in the Fen Country, and in Ireland. Candle-wicks are ordinarily made of fine cotton yarn ; Turkish cotton rovings are said to be the best, but of the cotton employed for this purpose there is certainly a great deal more imported from the United States than from Asia Minor. The wicks of night-lights vary greatly in composition, according to the fancy of the manufacturer. Sometimes little sections of rush are used, as well as very fine cotton yam ; but the majority consist of " inkle," a fine flax yarn. The manufacture of cotton and flax wicks is now performed almost exclusively by machinery, the threads of fibre being bound together either by twisting or by braiding. For dip candles, the wicks require to be bulky and of loose texture, in order that the melted tallow may rise freely. They are therefore made by twisting, and constitute the simplest form of wick after rushes. The cotton yarn chosen for the purpose must be " oozy " or furry, and the threads must be free from twist. This is placed ready balled in the cutting machine, a simple contrivance already repeatedly illustrated elsewhere. By it, the yarn is doubled in proper lengths around a rod ; a knife then descends and severs the yarns, to which a twist is communicated, by means of a rolling apparatus worked by a treadle. The twist is secured by dipping the wicks at once in molten fat. Twisted wicks have a great drawback, inasmuch as they are only very partially consumed in the flame, and thus necessitate the troublesome operation of snuffing. The first attempt to remedy this evil was made by Price's Candle Company, on the occasion of the Queen's marriage. The candles were made self-snuffing, by means of plaiting the wick, and " gimping" strings of wire, or other fibrous material, into the plaits, with the object of bending the wick outwards, so that the end of it should reach the oxidizing part of the flame, and thus be destroyed. A simplification of this plan consisted in plaiting the wick with strands of unequal length, by which the same result was attained. In these cases, the wick was round. At the present day, plaited wicks are made flat, by which means they acquire a natural inclination to bend. For all kinds of moulded candles, plaited, or in technical language, " braided," wicks are used, the old-fashioned twisted wick being reserved for " dips." An improved form of wick-plaiting machine is shown in Fig. 467 ; of a triple set, one apparatus only is seen. The contrivance is simple, but very ingenious. The strands of cotton yarn are carried on three revolving bobbins, whose gyrations are regulated by the beater beneath. The plaited CANDLES. 591 wick is passed away in an endless rope over the wheels In principle, tlds is identical with ordinary braiding machines, but it differs from them in always having but three bobbins. Given proper materials, the success of a wick depends upon the manner in which it is plaited, and especially upon the relative tightness of the plaiting. Stearine candles require a moderately tightly braided wick ; for paraffin, the braiding must be extra tight ; for sperm and wax, on the other hand, it needs to be unusually loose. Few candle-makers plait their own wick, at least in any quantity; they prefer, in most instances, to entrust the work to cotton spinners who make it more or less a specialty. The leading firm in this busi- ness is Haynes and Co., of Hampstead Eoad, London, who will courteously afford every information. After being twisted or plaited, the wicks are bleached in the ordinary way, and thoroughly dried. Before being used by the caudle-maker, they are dipped in a bath of pickling liquor, the effect of which is to retard combustion, and to help in causing the destruction of the ash. The pickle most commonly employed is a solu- tion of about one pound of boracic acid in 75 pints of water ; in this, the wicks are soaked for about three hours. When taken out, they are either wrung, or put into a centrifugal machine, to remove the first excess of water, and are then com- pletely dried in a tinned-iron box, pro- vided with a steam jacket. Various other pickles are recommended ; the principal are 1, A solution of 5 to 8 grms. of boracic acid in 1 litre of water, to which 0'3 to 0'5 per cent, of sulphuric acid has been added ; 2, a solution of phosphate of ammonia (used in some Austrian works) ; 3, a solu- tion of sal-ammoniac at 2 to 3 Beaume (proposed by Dr. Bolley) ; 4, a solution of 2 oz. borax, 1 oz. chloride of potassium, 1 oz. nitrate of potassium, and 1 oz. chloride of ammonium in 3 quarts water; 5, the wicks of the newly-introduced "snuffless dips " are plaited, and are then soaked in a solution of nitrate of bismuth. CANDLE MANUFACTURE. Having described the nature and preparation of the materials which, In one form or another, constitute the two component parts of every candle, the next consideration will be the manner in which their combination is effected. Two plans only are in vogue, each exceedingly simple ; one is known as dipping, the other as moulding. The former is employed for common tallow candles, which are accordingly called " dips." The rods supporting the twisted wicks, as they come from the twisting and cutting machine, are transferred to a frame capable of being raised and lowered at will. This commonly takes the form of a beam, but a better arrange- ment is seen in Fig. 468. The frame, made of iron, and capable of revolving, is so suspended that a perfectly horizontal position is always maintained, even under undue pressure at either end ; in this way, are secured a uniform length of candle and a plumpness at the top, which is difficult of attainment even by skilful workmen by the ordinary beam. Under the frame, are placed troughs containing melted tallow, into which the suspended wicks are repeatedly dipped. After each dipping, the adherent fat is allowed to cool sufficiently to retain a new coating on fresh immersion. The process is renewed until the candles have grown to the proper thickness ; they are then left to cool and harden. Dip candles are still largely manufactured, and are much employed in mines and small factories, and by domestic servants, as well as in cottages ; but within the last three or four years they have there been largely replaced by the small moulded " cottage composites," made from distilled fatty acids, with a self-consuming wick. These are, in fact, small and cheap composite candles, made in the same sizes as the old tallow " dips," and at nearly the same price. 592 CANDLES. They are very largely manufactured by several firms, among whom may be mentioned Christopher Thomas and Brothers, of the Broad Plain Soap and Candle Works, Bristol. By far the greater number of candles now manufactured are moulded, by which they acquire a much more finished appearance. The most simple form of moulding machine is that known as the " hand-frame," which is in use only among small manuiacturers. The form commonly used is that made by Biertumpfel, of Albany Street, Regent's Park, and shown in Fig. 469 ; A, stan- dards and water-box, with candle moulds partially enclosed ; B, movable clamps, for holding the ejected candles ; C, handle of eccentric wedge, for opening and closing the clamps; D, pistons, having the tips soldered at the top ends, which are fitted to the lower ends of the candle moulds ; E, cotton bobbins, revolving on strong iron pins ; F, crank handle, for raising the pistons, by the action of which the newly made candles are ejected into the clamps ; G, handle of gun-metal gland cock, for emptying water-box (this cock is so arranged that it cannot leak or get out of order) ; H, overflow pipe, which prevents the box from being overcharged with water ; I, newly made candles, held by clamps while the melted material id being poured in, so that the wick is centred in each mould ; J, a clearing pin, to enable workmen to clear the bend of the overflow pipe if it should become choked ; K, a pipe to admit hot or cold water to the water-box. The method of using the machine is as follows: After having made the connection between the hot and cold water pipes and the machine at K, and having connected the outlet pipe with a drain, the machine is ready for cottoning. The pistons are raised by turning the crank handle F, until the tips are level with the butt ends of the tin candle moulds, where they can be held by the pawl catching in the pinion. A fine wire, doubled, and of sufficient length to go through the tip-mould and piston, is then inserted, and extended below the piston sufficiently to enable the operator to pass the candle wick end tl i rough tlie loop. This permits the c cotton to be drawn up through the mould ; it must then be secured in any convenient manner during the first filling. The crank F is returned, the melted material is pour* d in, and the operation is complete. When nearly cold, the butt ends of the candles are shaved off with a tin scoop or a wooden spud. The clamps B should be placed open over the machine ; the crank handle F is then turned, and the candles are ejected into the open clamps. These are then closed by the handle C, so that each candle is held in its proper position. The crank handle F is then returned to allow all the pis- tons to recede into their places ; the wicks are thus held in a central position by the candles I and the cotton bobbins E. The cotton should be slightly strained under the piston plate. The melted material is again poured into the moulds to form a second batch ; when these are nearly set, the wicks are severed under the clamps, and tlie first batch is removed in the clamps. The temperature of the water in the machine is easily regulated, by shutting off or admitting hot or cold water, as required, at the "]" connection at K. The internal immersion pipes, situated inside the water-box and between the rows of moulds, are perforated. These machines occupy only about 3 ft. x 2 ft. of space, and are made to mould candles from 1 Ib. each to 56 to the Ib. It is also possible to make candles of two different CANDLES. 593 diameters, or several different lengths, in the same machine. A polished appearance is given to the candles by alternately admitting hot and cold water into the water-box ; the adjustment of the temperature is an operation needing special experience, the men's fingers forming usually their only thermometer. Another form of moulding machine is shown in Fig. 470. It is manufactured by Galabrun Freres. of Paris, and is in general favour on the Continent ; it is said to be capable of turning out 200 candles per half hour ; but it is only suitable for stearic acid, 470> or similarly hard material. When moulded and cold, the candles are taken to little tables, fitted with circular knives re- volving at high speed. Here the butt ends are trimmed, and the length of the candles is ad- justed to the weight. Some of the superior kinds of candle undergo a special polishing operation, performed by sub- jecting them to the friction of felt and other substances. la Fig. 471 is seen a trimming, washing, and polishing machine combined, as made by Gala- brun Freres. Modifications of Candle Manu- facture. a. Double wicks. Some very thick candles, such as the so-called " police-lights," and others, used in ships' lanterns, &c., are made with double wicks. Ordinary frames cannot be used in this case. The wick is threaded on a kind of metallic skewer, which is thrust into the centre of the candle mould. When the candle has partially cooled, the skewer is withdrawn, and the wick is left behind. The space left vacant by the extraction of the skewer is filled up with candle material. 6. Fancy patterns. Instead of the plain cylindrical form, candles are sometimes made in a variety of fancy patterns spiral or ropelike, with figures to indicate the hours, &c. These require special moulds. c. Self-fitting ends. Many candles are now moulded with conical bases, so as to fit any holder. For these, a little tin mould is fixed above the ordinary frame mould. d Coloured candles. For colouring candles, vegetable dyes are almost solely used. In these 2 Q 594 CANDLES. extravagant days, candle- makers are often required to supply an article of a tint which will match some particular ceiling or wall paper, and no little ingenuity is required to ensure such tints being permanent. As an illustration of the demands made by fashion, it may be mentioned that Price's Candle Company keep 300 varieties of candle always in stock, and are open to make 1000 different kinds (including size, colour, and material) in case of need. Though electric lighting lias emerged from embryotic obscurity into a palpable, fully-developed fact, much to the consternation of the gas companies, there is no reason to suspect that it will, within a proximate date, at all displace candles. With abundant evidence that the antiquated rushlight is still an article of domestic use Messrs. Haynes supply between three and four tons annually, prin* cipally to the University towns, there is safety in predicting a long life for paraffin, stearine, and composite candles, and even for the humble " dip." Illuminating Value. It is somewhat remarkable that the public, in judging of the value of a candle, are entirely guided by its mere appearance, and more particularly by its colour. The primary object of a candle is to give light. In estimating the value of any light-giving material, three factors have to be taken into account, viz. : (1), the cost of the material ; (2), the rate of its consumption ; (3), the luminous intensity produced. In practice, a sperm candle burning at the rate of 120 gr. an hour, is taken as the standard light with which all others are compared. Thia is the explanation of the phrases " sixteen-candle gas," electric light of so many thousand " candle- power," and so on. Such a standard, however, is unsatisfactory at best, since very slight in- equalities in the wick, or changes of its curve in the candle flame, materially affect the luminous intensity, without appreciably altering the amount of sperm consumed. Various other standards have been proposed, but none are thoroughly reliable. (See Photometry.) The following tables are the result of experiments by Dr. Fraukland, F.R.S., as to the luminous intensity, cost, &c., of various sources of light : I. Quantities of different substances required to produce the same amount of light. Young's paraffin oil 1 00 gal. (about 8 Ib.) American rock oil . . 1 28 Paraffin candles ..18 'Gibs. Sperm .. 22 '9 Wax candles Stearic acid candles . . Composite Tallow 27-6,, 29-5,, 36-0,, II. Cost of different sources of light equal to that of 20 sperm candles, each burning for 10 hours, at the rate of 120 gr. an hour. *. d. 7 2J Wax Spermaceti 68 Paraffin 3 10 Tallow .. .. ..28 Sperm oil .. .. American rock oil Paraffin oil Coal gas .. .. *. d. 1 10 6J 5 4J Although it is impossible to avoid the inference from the above figures, that candles in any form are very expensive illuminating agents, compared either with coal gas, or paraffin oil (or any of its numerous modifications), nevertheless, the numerous advantages which they possess render it exceedingly unlikely that they will, to a greater extent than at present, be superseded by either of the two cheaper methods of illumination. Neither coal gas nor paraffin oil can be employed except at what are, for all practical purposes, stationary points; they cannot be carried about, while evolving light, from one place to another, and are altogether destitute of that element of portability, which renders the candle so valuable. Further, except in so far as a fire may result from actual contact between a candle flame and any inflammable substance, candles are absolutely safe illuminating agents, and persons burning them are not liable to the alarming explosions and fires which resuli from the careless use of gas, or of paraffin lamps. Notwithstanding, therefore, the competition of gas and petroleum, and, it may be added, possibly of the electric light, there seems no reason for believing that the caudle trade will do other than increase with the needs of the population, and will continue to repay every effort devoted to its improvement which is founded upon truly scientific and sound commercial principles. Night-lights. The making of night-lights is an important branch of candle manufacture. In 1877, Price's Candle Company, who enjoy almost a monopoly of the production of these useful articles, turned out 32 millions of them. There are two distinct kinds of night light ; the common form, so long known as Child's, from the inventor, whose son now manages this department of Price's Candle Company's factory, and the Company's new patent night-light. The former are made by running molten fatty matters into little wooden cases, which are the result of a series of operations. Balks of timber, free from knots, are the foundation of the manufacture ; the best American pine is preferred, but it is now becoming scarce and dear, and the so-called " tulip-wood " has often to be substituted for it. The balks of timber are brought under a huge planing machine, which shavi s CANE. 595 off beautifully even slices, no thicker than stout paper. These are used as well for the boxes in which the night-lights are packed for transport as for the cases of the night-lights themselves. It is perhaps a little out of order, but at any rate it is convenient, here to complete the account of the manufacture of the packing boxes. The slices of wood are cut into rectangular form of the required size, and corresponding sheets of tough, but very thin, paper are pasted over them, by boys, at great speed. In this condition, they are pressed, to ensure adhesion, and are then taken to a machine for the purpose of having incisions made in them, where the edges are to be turned up to form the sides and ends. The cutters of this machine are so beautifully adjusted, that they completely sever the wood without so much as scratching the paper backing, which remains to form the hinges or angles. The same thin slices of wood are used in making the night-light cases. The slices, each of a size to form about a dozen cases, are coated with paper. This, like all the remaining processes in the manufacture of Child's night-light cases, is performed in a most dexterous manner by girls. The slices are placed on a table before a girl, who with one hand pastes a printed yellow label on the wood, while with the other hand she coats the paper label with gum, which gives it a glazed appearance, and at the same time renders it waterproof, the latter being an important consideration, as the light has to be burnt in a saucer of water. The double slices are immediately rolled to a given diameter, and are then carried on trays to a heated room to dry. After drying, each roll ia subdivided into the proper number of cases, by means of a lathe, at the rate of 150 per minute. Next they are bottomed with cardboard, by means of a fitting stick, and an aperture is punctured in the centre for the introduction of the wick. This is provided with a tiny square tin-foil sustainer, which is secured to the case by means of a single drop of wax. The cases, thus prepared, are placed on trays to be filled. This operation is entrusted to boys, who manifest a skill aud exactitude quite astonishing, and have proved themselves superior to any mechanism which has yet been tried for the purpose. The creamy fat is poured from a can with a narrow straight spout, sufficient being tipped at one operation into each case to exactly fill it and no more. When cool, the exterior of each case is scraped with a blunt knife to remove accidental splashes, and the lights are ready for packing in the boxes already alluded to. The new patent night-lights differ from the foregoing, not only in being made from very much better materials, but also in the method of manufacture and mode of burning. Cases are dispensed with, and the fatty material, usually derived from palm oil, is moulded to the required shape by being run into a frame, which consists of a number of moulds or cups securely fitted to a bed of iron or wood. Into these, the melted material is poured and left to cool. When cold, the excess of fat is scraped off with a blunt tool, and the night-lights, ready punctured for the insertion of the wick, are lifted out by a screw. The wicks are introduced by boys On each wick, cut to the proper length, is threaded a tiny square of tin-foil, which is to serve as a support for it during the latter stage of the combustion of the light ; the wick is then thrust through the little disc of opaque white fat, and is secured by a cleat effected by a sharp blow on a miniature vertical anvil. The rapidity and precision with which the lads perform this operation is something to admire. The lights are now ready for burning, for which purpose they are placed without water in little glass cups. Night- lights are made of various sizes, calculated to burn for six, eight, or ten hours. (See Glycerine; Oils; Ozokerit; Paraffin; Photometry; Soap; Spermaceti; Wax.) W. L. C. CANE. (FB., Canne ; GER., Rohr.) The term " cane " is properly restricted to the class of plants known as " rattans," included under two closely allied genera, Calamus and Dcemonorops, of which there are many species. They are generally classed among the palms ; but they seem rather to form the connecting link between palms and grasses, uniting the habits of the former to the inflorescence of the latter. On the differences in their methods of growth, has been founded their classification into " ground rattans," and " climbing rattans," the latter being by far the more numerous and important. Nothing can be imagined more graceful or beautiful than a cane-bush. The plants often grow in extensive plots ; but frequently also as single specimens, creeping to the tops of the highest forest trees, falling again in festoons, alternately trailing nnd climbing. They sometimes attain the enormous length of 500 ft., though more commonly 250 ft. is the limit, with a diameter somewhat less than half an inch. During growth, the plant is sheathed in a case of numerous and most beautiful leaves, which are strippi d off when preparing the canes for market, leaving distinct rings to mark where the leaves have sprung from the stem. The stem, leaves, and tendrils are covered with terrible thorns. The fruit hangs in clusters of about fifty berries, each as large as a cherry, bright, cream-coloured, and edil.le. The stem contains much water, which may be extracted by cutting off a section and blowing through it. The roots and sprouts, when just above the ground, make a good vegetable. The plant requires a moist rich soil. It is very widely distributed throughout the Indian Archipelago, Malay Peninsula, China, India, Ceylon, Africa, and Australia, being specially abundant in all the moist tropics of the East, both continental and insular. 2 Q 2 596 CANE. Over fifty varieties of Calamus have been identified ; those principally entering into commerce are the following : C. rotang ; stout. rudentum ; indigenous to the Moluccas. vents; indigenous to Cochin China and the Moluccas. draco ; indigenous to Sumatra and the Moluccas ; furnishes the " dragon's blood " of commerce (see Kesinous Substances) ; this and the two preceding are varieties of C. rotang. erectus; found at Silhet, in India. Scipionum ; most abundant in the Malay Peninsula ; slender ; supposed to yield the malacca cane brought from Siak. Royleanus; grows the farthest north of any, being found at Dheyra Doon, in India, and plentifully in all the eastern forests of Kumara. gracilis; 1 tenuis ; \ indigenous to Chittagong and Assam. extensus ; ) australis ; indigenous to the Louisiade Archipelago. petrceus ; a variety of C. rotang. Rattans, or rotans, are among the most abundant of the trees indigenous to the Straits Settle- ments ; the many varieties are distinguished by the natives as follows : Sigga ; knotted, iised for chair bottoms. Tiga segi; three-sided. Kawat ; used for rigging. Tawar ; grows on river banks, and drops in long tendrils armed with thorns, which will pull a man out of a boat. Mannau; used for walking-canes. Samamboo; also used for walking-sticks; dark coloured and glossy, with joints far apart; grows to many hundred feet in length. Dhannan ; very long and thidk ; perhaps the largest cane of the species. Sinnee; long and delicate; colour, white; used by Malays for rigging and cables. Ligor benar ; true rattan. Jomnng ; yields " dragon's blood." Salak ; produces edible fruit : Calamus zallacca. Bumban ; ground rattan ; grows straight up ; length, about 7 or 8 ft. ; used for tying on thatch. Saboot ; used for cables and rigging. Binni, or Dinni; has poisonous leaves. Oodang ; red rattan ; used for blowpipes for native poisoned arrows. In Borneo and Sumatra, rattans abound in all the old and dense jungles in damp situations, and form almost the principal vegetable production. The rattans of Borneo are esteemed finer than those of any other part of the world ; they are exported to Singapore and Batavia in immense quantities from the Coti and Banjar rivers, on the southern and eastern parts of the island. They are collected and brought down these streams on rafts by the Dyaks, for very small remuneration. The principal supplies of Borneo are gathered at Banjarmassing (fine sort), Pontianak (common), Coti (small, fine), Sarawak (fine and coarse), Sambas (very long, mixed); the chief places of production in Sumatra are Jambi, and Pandagon on the west coast (glossy kind) ; Perak is the most important locality on the Malay Peninsula. The Bugis traders of Borneo barter European and Chinese productions with the natives for the canes. These are then taken to Batavia, Somataya, Singapore, Penang, &c., and are there purchased by European merehants, and shipped to London and Liverpool. The majority of those produced at Coti and Banjarmassing go to Holland : those from Perak, to Penang, being re-shipped thence to London, and known as " Penang quality." All the rivers of Northern Borneo abound in canes, and 4000 tons might be cut every year without exhausting the supply. The inhabitants would contract to cut them for a trifle ; but the cost of carriage to shipping ports and for freight would equal 50 or 70 per cent, on the first cost. By far the most valuable rattan, perhaps a distinct species, is brought from Banjarmassing, on the south coast of Borneo. It is worth 150 per cent, more than any of the others. Vast quantities of rattans are shipped from the Malay Archipelago to Europe, India, and China, probably amounting in all to four or five millions from British territory alone. A few species are found in Madras territory ; but in India they chiefly abound in the forests of Chittagong, Silhet, and Assam, whence they extend along the foot of the Himalayas as far north as Dheyra Doon. The East Indian rattans from Calcutta are very inferior, and usually glossy; those from the Eastern Archipelago are, except the Penang and Sumatra varieties, not glossy. Rattans of rather coarse kind are found in all parts of Formosa. A small trade is done in them to CANE. 597 the Chinese coast, where their low price often affords them a market before the finer but dearer kinds from the Straits. The most common " ground rattan " is the Rhapis flabelliformis, which grows all over China, but especially in Lin-kin and the southern districts. It attains a height of 30 ft. and upwards. Most of the fibre used by the Chinese is from the bark of this plant (see Fibrous Substances). Their great use among us is for walking-sticks, for which purpose they should be chosen tapered, heavy, well glazed, and with short joints, preferably those with roots attached, and always of sufficient length to cut up into a definite number of sticks, 38 to 42 in. long, without waste. The mode of collecting rattans is as follows : A native goes into the forest with his parang, or bill-hook, to cut as many as he can carry. Having cut a cane, he hacks a notch in the nearest tree ; next he strips off a small portion of the outer bark of the cane, and inserts the peeled part in the notch in the tree. By simply pulling it through, he easily and rapidly divests it of its leaves and epidermis. When he has gathered and peeled about 300 or 400 canes, which are as many as he can carry in a green state, he sits down, doubles up each one, and ties them in bundles of 25 to 100. All that is necessary to fit them for the market is drying, a very easy matter in a tropical country. By this process, the canes assume the yellow colour with which we are familiar, some becoming glossy, others dull. On account of the small amount of labour entailed in their preparation, they can be sold very cheap. The natives usually sell them by tale (100) ; the Chinese merchants, by weight (the pi<.u>, or 133 lb., containing nine to twelve bundles) ; in India and the United Kingdom, they are sold by tale, and are imported hither in bundles of 100, worth from Is. 6d. to 3s. On account of their lightness, flexibility, length, and strength, canes are applied to a great many purposes in the countries where they grow. One variety, C. rudentum, is used in enormous quantities for cables, cordage, and fishing-lines, after being split and twisted. The splitting is performed longi- tudinally ; the canes are then soaked, and attached to a wheel. One person turns this, while a second binds the split cane together, adding others to the length from a quantity carried round his waist. From the cordage thus made, bridges, hundreds of feet in length, are constructed ; over these, laden men, and even men on horseback, pass with ease. In China, houses and sheds are built of rattan, at a cost of about 5 dollars each. Much of the beautiful and elaborate basketwork of the Chinese and Japanese is from this source. Mats made from split cane are exported from China t ~> all parts of the world. Very large quantities also are employed as thread, for sewing pieces of fabric together to form coverings for boats, carts, &c., as a substitute for tarpaulins ; and for joining the leaves of palms, constituting the roofs and sides of dwellings. Another very wide application of thin threads of the cane is for the bottoms of rice-sieves. The well-known broad-brimmed Chinese hats are made of the same material plaited. The applications to which canes are put in this country are scarcely less important and varied. For all large baskets, such as are used in cotton mills, sugar refineries, and most factories, as well as for those employed on railways, and by gar- deners, hucksters, coal-dealers, and washerwomen, canes have almost entirely replaced wiLow, buffalo hide, &c. They are unusually well adapted for making the baskets used in transporting carboys containing acids forming an important branch of the basket-maker's trade as the silica contained in the outer bark serves as a protection against the acid, which is sure to be spilled on them sooner or later. The manufacture of balloon cars, rustic and garden chairs, lattice-work, meat- safes, and brooms, also consumes a large quantity. Rough matting also is made of rattan, and is sold at 2s. to 2s. 6d. the square yard. In Fig. 472, is seen a machine which is used for splitting rattans. One of its chief advantages is, that it produces from the centre of each cane a, a perfectly round and even rod c, of considerable value for making orna- mental window blinds, fancy baskets, chairs, &c. ; whereas with the old- fashioned method of hand splitting, this core is sacrificed, in order to obtain the strips of outer surface. The cane is carried past the hollow cutter by revolving feed rollers, other rollers being placed beyond the cutter, for drawing out the central core. The cutter is so constructed that it divides the cane at one passage into any desired number of strips 6, at the same time removing the 598 CARAMEL. central core c. The rate of feed is 1 50 ft. a minute ; by simply changing the cutter, the cane can be cut into strips of any desired width. A great improvement consists in the feed rollers being arranged to work horizontally ; the strips otcane as they leave the cutter are thus easily collected. The machine weighs about 7 cwt., requires only J horse-power, makes 200 revolutions a minute, and costs about 551. It is made by Messrs. Ransomes, of Cht Isea, from the designs of Mr. John Fisher, of Mincing-lane and Singapore, who has secured patent rights for its application in the Straits Settlements, the headquarters < f the export trade in canes. For making the seats of cliairs and similar work, an industry which consumes probably half the rattans imported into this country, the selected canes should be long, of bright pale-yellow colour, small size, and not liable to break All such as are dark coloured and snap short on bending should be rejected. Four pounds of rough rattnn are required to yield one puund of strips for cane work. A large quantity of cane is now used, as a cheap substitute for whalebone, in umbrella and parasol ribs; a set of cane ribs for the former costs only 1\d. and for the latter, be conducted by the branch steam-pipe m into the upper part of 6, as shown. If sufficient pressure be used, the steam will force all the liquid bisul- phide through the fibrous mass in the vessel, and up a vertical pipe n 4 , the tap m s being opened for that purpose, and the two-way tap rf being turned so as to direct the liquid bisulphide by the horizontal pipe n 3 to the still g', or, if desired, to the tank a through the two-way tap n 9 . By this mode of working, the steaming may be finished at one operation, with great economy of time and material. In some cases, however, it will be found convenient to use a pump n, which will draw the liquid through the pipe n 1 from the space below the perforated plate 6* (the tap n" being opened and the taps n 5 , n?, closed), and will force it up the pipe n 1 into the tank a above. The steam admitted to the upper part of the vessel b through the pipe m will percolate through the fibrous mass, and drive the liquid bisulphide into the space below the perforated plate b*. Before the fibrous substance is removed from the vessel b, an atmosphere of steam is driven through the mass from the perforated coil c. The bisulphide is volatilized by this means, and the vapour is conducted up the pipe p to the condensing vessel g, where it is reduced to a liquid state, and may then be run back again into the tank a. A small closed tank r is provided between the extractor 6 and the pump n, into which the bisulphide may be allowed to flow through the tap n 7 , in case of accident to the extractor or pump. A draw-off tap n* is provided at the bottom of the vertical pipe n 2 , to empty it previous to taking the pump to pieces for inspection or repair. It will be seen that the pipe p communicates with the worm g' of the condenser, and that both it and the CARBON BISULPHIDE. 607 pipe d' are provided with a tap, for closing communication with the worm when required. The bisulphide may thus be used over and over again, and a large quantity of material be thoroughly cleansed from grease with very little waste of bisulphide, as none of the vessels are opened wl.ile there are any signs of the bisulphide being present. A running-off tap q is adapted to the bottom of the vessel 6, for the purpose of letting out water or other liquid, used from time to time for cleansing the vessel. The tank a is provided with an overflow pipe, for withdrawing any excess of water resulting from the condensation of the steam used in vaporizing the bisulphide, and for blowing off the air which enters the apparatus during the operation of charging. In the extraction of bitumen from schists, about 5 per cent, more product is obtained by treating with bisulphide of carbon than by the destructive distillation process, which, besides being very expensive, only yields about 8 per cent, altogether. For this purpose, the bisulphide is largely used in Galicia. In the same country, it is employed for extracting sulphur from a gypseous earth containing about 14 J per cent, of that mineral, with a loss of only about 1 66 per cent, of bisulphide. It is essential that the sulphur earth to be treated shall be perfectly dry, or the bisulphide cannot perform its duty. The very low boiling point of bisulphide of carbon has caused engineers to turn their attention towards using it as a motive power. The Ellis bisulphide auxiliary for reducing the consumption of fuel for steam engines, is already well known in America at least. It can be fitted to all systems of steam engines, whether expanding or no, and requires no essential alteration in the construction ; but lubrication must be effected with water, as grease would be dissolved. Our American cousins have gone yet another step in advance. Glycerine has no affinity for bisulphide of carbon, and is capable of mechanical evaporation in the presence of its vapour ; it is a much better conductor of heat than water, and is capable of being heated to a certain degree with a less proportion of fuel, also of storing up caloric. When heated in a metal vessel, it becomes thin, and spreads over the surface, forming a protection and lubricator. The bisulphide is easily evaporated to a dense vapour, the latent heat absorbed for vaporization being about 280 F., that of steam about 1000 F., or a saving of 71 per cent, in the fuel. To utilize these substances in the creation of motive power, the apparatus shown in Fig. 474 has been constructed : A is a boiler ; B, a condenser ; C, a force- pump ; D, a feeder ; and E, the cylinder of an ordinary engine. To produce power, the boiler A is filled with glycerine, and heated to a temperature of 43-260 (110-500 F.); the valve b is opened, and a small quantity of bisulphide is run from D, through a perforated pipe a, into the boiler, and is thus brought into contact with the heated glycerine G, pro- ducing a pressure of vapour corre- sponding with the amount of bi- sulphide allowed to enter. The engine is now started by opening the inlet valve on the supply pipe c, and the vapour, after impart- ing its force in the cylinder, is discharged into the exhaust pipe d, which proceeds direct to the condenser B, when it passes through a series of worms, cooled by water flowing into the cistern e by the valve /, and out by the overflow g, and is thus condensed again into a liquid form, run down into the receiver A, and stored for future use. To regulate the flow of bisulphide so as to obtain a uniform quantity, the receiver h is connected by a double pipe ij with the force-pump C, and by the pipe k with the feeder D, so that the latter vessel, which holds a quantity of the material, is supplied as required, and regulates a steady flow by the valve 6, independent of the action of the pump. To ascertain the contents of the feeder and receiver, two glass gauges are fixed at I, m. At n is a gauge for indicating the amount of vacuum produced by the condenser, and therefore useful to determine the necessary quantity of water by the inflowing valve /. The feeder D has a valve p and a pipe o at its upper part, direct to the top of the evaporator or boiler, so as to equalize the pressure and flow of the liquid bisulphide by the valve 6, as before explained. To ensure against any loss of material through accidental excess of pressure, a safety valve is connected by a branch pipe s to the exhaust pipe d, the excess being then saved by passing direct to the condenser. The presence of air would partially prevent the condensation of the bisulphide, and cause a back pressure instead of a vacuum ; therefore, before running in the bisulphide by the funnel v, or on starting for the first time, the air is exhausted as far as possible, by working the pump C by hand, closing the circuit by valves 6, p, and opening t. During evaporation, the small portion of glycerine forced from the bulk proceeds with the vapour through all the pipes, &c., to the cylinder by which 608 CATGUT. the power is utilized, and their gravity being nearly the same, the liquid bisulphide does not sink down or come in contact with the metal of the buKer, but is discharged as vapour from the surface of the bath of glycerine. This vapour may be utilized by any kind of engine, and may be led by the exhaust pipe direct to the condenser, for the purpose of extracting the latent and sensible heat, reconverting it for re-use. Statistics and Cost of Manufacture, $c. The principal seats of the manufacture of bisulphide of carbon in England are London (2), Ironbridge, and Manchester (1 each). Paris possesses 2 large works ; Bordeaux, 1 ; and Marseilles, 3. There are several manufactories in Germany ; and, in the Austrian dominions, 1 (in Galicia). Though not exactly a newly established manufacture, it has only attained its present growth within recent times. It is constantly increasing, and will doubtless continue to do so, the more so as the valuable properties of the substance become generally known and appreciated. It is in the hands of a few who have made it a special stuuy ; there are probably not twenty manufactories of it in the whole world. The capital required to carry on the manufacture is comparatively small, the great essential being skilful and careful management. The cost of production, as stated by Payen, is as follOW8: - s. d. Sulphur, 2200 Ib 868 Charcoal, 10 sacks (660 Ib.) 1 13 4 Labour 1 men by day and 4 by night, with 2 to pound the sulphur 1 16 8 4 children preparing the paper and 4 filling cartridges 10 Fuel coke 110 bushels at 4d. per bushel 200 Cost of rectifying, cleaning, interruptions, and interest.. .. 1 13 4 16 Deduct sulphur recovered, 330 Ib 150 Nett cost of about 15| cwt. of bisulphide of carbon 14 15 Sells at . 16 5 Profit 1 10 The differences between the theoretical and practical production are as follows : 1. Charcoal : 1760 Ib. of bisulphide obtained = about 278 Ib. carbon ; the 660 Ib. of wood charcoal (excepting moisture and impurities) would represent a loss of 387 Ib., or more than 50 per cent. 2. Sulphur : 1760 Ib. of bisulphide = 1482 Ib. sulphur + 330 Ib. recovered = 1812 Ib. ; then the loss on 2200 Ib. employed would be 388 Ib., or 17 per cent. According to E. van Haecht, the cost of three days' working ia : s. d. I s. d. Sulphur, 4189 Ib 12 7 Labour 200 Coke . 140 Wood charcoal 1 18 Wear and tear . 17 18 6 The commercial value of the refined product, containing about '001 to '005 of impurities, prin- cipally an alliaceous oil, varies between about 20Z. and 25Z. a ton, according to the fluctuations in tlie prices current of sulphur. Greater purity than this is seldom required, but may be obtained at a rather higher price. The quantity of bisulphide produced in the United Kingdom probably does not exceed about 1500 tons per annum. It is not imported, nor is it exported in any appreciable quantity. It is transported in drums of sheet iron, or small metallic canisters, of any desired size, which arc closed by screw stoppers fitting with absolute exactness, so as to prevent any possibility of the vapour escaping. In this way, it may be sent any distance without danger. The chief consumers are indiarubber manufacturers and sulphur refiners, besides oil and fat refiners. The retail trade is very limited, and passes almost entirely through the hands of chemists and druggists. (See Indiarubber Manufactures ; Oils ; Sulphur.) CATGUT. (FR., Corde de boyau ; GEE., Katzendarm, Darmsaite.) The term " catgut " is applied to membranous substances prepared from animal intestines, gene- rally those of sheep, more rarely those of horse, ass, and mule, but never those of the cat. Two methods of preparation are used, according to whether it is desired to produce twisted cord, or flat strips, of membrane. In the former case, the first stage in the operation is the thorough cleansing CATGUT. 609 of the intestines from the adherent feculent and fatty matters, after which the small ends are tied together, and placed over the edge of a tub, while their major portion is left for two days to soak in water, which is constantly changed. In this way, the peritoneal and mucous membranes are loosened. The bundle of intestines is then laid on a sloping board overhanging the tub, and their surface is scraped by a square steel edge, the external membrane being removed in breadths of about half the circumference of the intestine. This membrane, which the French call filandre, and which is employed for the cords of battledores and rackets, and also as a thread for sewing the ends of intestines together, cannot be removed by beginning at the large end. The scraped intes- tines are then steeped for one night in clean water, and next day are again scraped with a rounded edge ; this process is called " curing." The large ends are now cut off, salted, and stored in covered tubs for sale to the sausage-makers. The small parts are again steeped for one night in fresh water, and next day are treated with an alkaline mixture, consisting of 4 OB. potash, 4 oz. carbonate potash, and 3 to 4 gall, water. After this, they are distributed to a number of women, each having two basins of the alkaline solution before her, and are drawn through a perforated brass thimble, pressed against the edge, for the purpose of rendering them smooth and equal. They are thus passed from one to the other of the two basins several times, and are then assorted according to their sizes. In order to produce a cord known as " whipcord " from these intestines, they are sewn together by means of the filandre before mentioned, the joints being cut aslant to make them smoother and stronger. A number of these cords are then put into wooden frames, whose two uprights are fur- nished with a series of holes, containing pegs for securing the ends of the cords, and for passing the lengths round. The spinner attaches the end of one of the cords to the hook of a little whirling apparatus, similar to but smaller than the whirl of the rope-maker, which he causes to rotate rapidly by means of a handle. This puts a twist into the cord, and somewhat diminishes its length ; the twist is retained by pegging the cord on to the frame. The others are then treated in this way, and when all are completed, the frames are piled up horizontally in a small close chamber lined with thin sheet lead, where they are subjected to the fumes of burning sulphur. This process is called " bleaching," but that is a misnomer, as the alkaline solution has already whitened the gut ; the real object of the sulphuring is to prevent the putrefaction of any animal matter which may still be accidentally adhering. The cord may now be dyed black with common ink, or red with red ink, or green, taking the dye readily. The twist being completed, the cords are nicely smoothed, and then placed for an hour or so in a hot room 82-93 (180-200 F.) which fixes and consolidates them. Lastly, they are cut off the frames and twisted into cords for sale. The so-called " hatters' cords," for bowstrings, used in one of the stages of hat-making, are made of the longest and largest sheep guts, which, after being properly smoothed and cleaned with the alkaline solution, are twisted in lengths, 4, 6, 8, 10, or 12 together, according to the intended size of the cord, which is usually about 12 ft. long. This cord must be free from lumps and knots ; when half dry, it is sulphured twice, and after each operation, is well stretched, twisted, and smoothed, and finally dried in a state of tension. Clock-makers' cord must be very thin, strong, and durable, on which account it is made from very small intestines, or from larger ones slit up in the direction of their length, by a couple of razor blades fitted into a ball of wood, which serves as a guide. The wet gut, being drawn over the ball, is divided, and the two sections, if properly directed by the workman, fall into a basin beneath. This operation is one of considerable delicacy ; but when well performed, the gut is divided, with great rapidity, into strips of perfect regularity. A number of these strips are twisted together, and treated as already described. In France, a very strong cord is prepared from the intestines of the horse, ass, and mule. The gut, having been scraped, is divided into four equal parts, by skilfully drawing it over a fixed knob containing four sharp edges, or two semicircular blades arranged at right angles. Four, six, or eight of these strips are tied at the end with pack-thread, then twisted together, and polished with dog skin. The cord thus made is employed, as a substitute for leather belting, on light machinery. The cords intended for the strings of musical instruments violin, harp, guitar, &c. require the greatest care in their preparation. The first scraping must be performed with great skill. A little alum is added to the alkaline solutions, which are made progressively stronger each day for four or five days till the membranes are well bleached and swollen. They are then passed several times through the thimble, spun, sulphured, polished by friction between horse-hair cords, and dried in the hot room. The best violin strings come from Naples and Milan, and are known as " Roman strings"; other Italian towns, where the industry is carried on, being Venice, Gubbio, Foligno, Bologna, Vicenza, Padua, Verona, and Bassano. Italy once enjoyed a monopoly of the manufac- ture, and, though strings are also made at Neu Kirsch, inVoigtland, .in Bohemia, in the Tyrol; in Lyons, &c., the Italian strings still retain a superiority over all others. They are as clear and' transparent as glass ; but their chief distinctive features are combined elasticity and strength. 2 B 610 CELLULOID. This is due to the leanness of the sheep, so that probably the Welsh, Highland, and South Down breeds of this country would give better strings than the Lincoln sheep. Emaciated carcases would also probably yield good strings. About three-fourths of the whole quantity of catgut consumed in Europe is said to be derived from Italy. The best and largest bass-viol strings, and a very considerable proportion of the guitar strings, are made in Germany. The manufacture of cord from the intestines of animals, for use in bows, and other weapons of war or the chase, has been practised from the earliest times; and its employment in musical instru- ments also dates from remote antiquity. Until recently, no industry was more disgusting than that of gut-making, on account of the putrefactive odours generated by the steeping of the intestines ; but the use of carbolic acid, and other deodorizers, in the liquors now prevents all smell, without in any way affecting the value of the product. Silkworm-gut. " Silkworm-gut," so-called, is the fine, strong fibre universally employed by anglers for attaching their hooks. It is obtained from silkworms, by taking them before they begin to spin, and very carefully pulling them asunder; the glutinous silk, contained in the sericteria or silk-glands, is then drawn into a single thread, of variable length, from 1 to 3 ft. ; it is then gently dried. We annually import small quantities of it, chiefly from Italy. Hitherto, silkworms only have been employed for the purpose ; but a plan has been set on foot to utilize the caterpillars which infest food plants. It is to be hoped that it will prove a practical success, as if the gut can be produced in long pieces, and at a moderate price, it will find numerous applications. CELLULOID, PARKESINE, or XYLONITE. (Fu. and GEB , Celluloid.-) " Celluloid " is decidedly the most convenient name for this product, as it is the one in general use. It consists virtually of vegetable fibre, treated with a mixture of nitric and sulphuric acids, and which, for want of a better term, may be called " pyroxyline," though it is not identical with that compound ; this is dissolved in a suitable solvent, and afterwards dried. The product is a light yellowish-brown coloured body, which can be carved, planed, turned, sawn, stamped, or polished, and made either opaque or transparent. It may be made as hard as ivory, which it closely resembles, but is always elastic, and may be moulded into any form. It can be spread on textile fabrics, &c., and, by placing different coloured layers alternately, and rolling them together while in a plastic condition, any desired marbled or granular effects may be produced. It is easily coloured any tint, and, as the colour permeates the whole mass, it is ineffaceable. It is plastic and malleable at 125 (257 F.), and decomposes suddenly, without taking fire, but with evolution of reddish fumes, at 140 (284 F.). It is non-explosive, and burns only when in direct contact with a flame. When pure, it is inodorous, and does not become electric by friction. An important property is that it can be united by means of its own solvent or cement ; and no waste is entailed in its use, as all scraps can be worked up again. The manufacture may be divided into two distinct stages: 1. The production of the so-called " pyroxyline ' ; 2. The treatment of this compound with solvents, in order to make it plastic, and give it other desired qualities. The first stage of the process suffers but little variation. A convenient quantity of cellulose or woody fibre, such as disintegrated cotton waste, paper, &c., ia fed into an open vessel called a " converter," and treated with an acid mixture composed of 1 part of nitric acid, sp. gr. 1 420 and 4 to 5 parts of sulphuric acid, sp. gr. 1 845, mixed in a separate vessel, and kept as cool as possible. The acid mixture is pumped or forced up into the converter, while the fibrous substance, previously placed in a hopper over the converter, falls gradually into it by an opening in the top. The charging of the cotton into the converter occupies about ten minutes, and at the end of twenty to thirty minutes at most, it is chemically converted into the so-called pyroxyline, or nitro-cellulose. This, together with the excess of acids adhering, is then allowed to fall through an opening in the bottom of the converter, and is caught in a large box provided with a false bottom of perforated iron, or wire gauze, at about 6 in. above the real bottom. On this, the wet mass remains for an hour, to admit of the excess of acids draining away as far as possible ; the still remaining impregnations of acid are then expressed by placing the pyroxyline in a cylinder with a perforated bottom, and subjecting it to hydraulic pressure. The result is a Lard cylinder of pyroxyline, containing about 5 to 20 per cent, of the acid mixture, in which state it is stored for future use. When required, the cylinders of pyroxyline are torn into dust by special machinery, such as that employed for grinding paper pulp, and the disintegrated mass falls into a large tank, where it is well washed with water, to remove the last traces of acid. It is then again placed in the cylinders with perforated bottoms, and pressed to remove the water, leaving in only 5 to 20 per cent. The solid cylinders of soluble pyroxyline are again broken up in the disintegrating machine, preparatory for the treatment with solvents, which forms the second stage of the manu- facture. This is performed in a variety of ways, chiefly according to the ulterior applications -for which CELLULOID. 611 the product is intended, and differing less in the apparatus employed than in the ingredients and proportions of the dissolving agents. One of the first solvents employed on a large scale was wood naphtha, distilled with chloride of lime, in the proportion of 1 gallon of the naphtha to 2 to 6 Ib. of fused chloride ; the more of the latter used within these limits, the stronger will the solvent be. The first 3 quarts of the distillate are collected for use ; the remainder is caught in a separate vessel so long as any spirit comes over, and is distilled again at the next operation with more fresh materials. The deposit remaining behind in the still is chloride of lime, dissolved in water, and contaminated with some tarry matter. It is run into an open iron vessel, heated by a fire beneath, to evaporate away the water, and fuse the chloride of lime ready for re-use. The solvent thus prepared is applied to the pyroxyline, in such proportions as to make a pasty mass ; but if used alone, the resulting celluloid would soon become hard and brittle. To avoid this, a certain quantity of oil is added to the mass, and kneaded up with it in the mixing machine. The proportion of oil will vary with the desired degree of toughness. To produce a consistency suitable for coating telegraph wires, or for spreading on textile fabrics, the proportion of oil may equal half the weight of the pyroxyline. If the oil used be first treated with chloride of sulphur, the compound is much more elastic. It is thus treated by mixing with 2 to 10 per cent, of liquid chloride of sulphur, according to the degree of elasticity required ; but the chloride of sulphur should first be diluted with an equal bulk or more of mineral naphtha, or bisulphide of carbon, to prevent too violent action. The prepared oil is compounded with the dissolved pyroxyline, in various proportions, but seldom exceeds 20 per cent. To increase the hardness and modify the colour of the product, sometimes a small portion of gum or resin, such as shellac or copal, is added, but seldom more than 5 per cent. The wood naphtha may be replaced by alcohol, and the chloride of lime by chloride of zinc, or manganese fused or dry. For economy sake, a small quantity of light spirits from coal may be mixed with the solvent, but it is not preferable. For the oil, may be substituted gum ballata, treated with chloride of sulphur usually not more than 5 per cent, of the chloride. The combustibility of celluloid thus made may be corrected by the addition of chloride of zinc, or tungstate of soda. Ten per cent, of either effectually prevents burning ; but usually much less will do, especially when, pigments are used. The same end is attained by employing iodide of cadmium, oxalate of zinc or manganese, or gelatine dissolved in glacial acetic acid. A practical difficulty attending the use of the above process is that the solvents employed are so volatile. Large masses of celluloid may be prepared better, quicker, and with less consumption of solvent by adopting nitro-benzol, aniline, or glacial acetic acid, and the celluloid may then be worked in the open air. The ordinary volatile solvents are improved by the addition of camphor. When using nitro-benzol, the commercial article should be distilled off hydrochloric acid or chloride of lime, say 6 Ib. of either to 1 gall, of nitro-benzol, which is thus rendered purer and sweeter. One hundred parts of pyroxyline are then moistened with ordinary solvent preferably naphtha distilled off chloride of lime and the excess of solvent is removed by hydraulic pressure. The other solvent is then added, in the proportion of 10-50 parts of prepared nitro-benzol or aniline, together with 10 to 50 parts of camphor, and 150 to 200 parts of oil, preferably cotton-seed or castor. This mixture is formed between rolls, heated by steam being admitted into them, till the whole forms a well-combined dough or paste, which will be more or less stiff, according to the quantity of solvent used. For a hard compound, the oil should be less than the pyroxyline ; for a soft one, it should exceed the latter say, 150-200 oil to 100 pyroxyline. In making celluloid with glacial acetic acid, 100 parts of pyroxyline are dissolved in 50 parts of the acid, for a stiff paste ; or 100 to 300 or more parts, for a semi-fluid consistency. Usually the pyroxyline requires to be dried before dissolving it. The conduct of this operation on large quantities requires much care and time, and a very large space of drying room, so that great advantages, on the score of cost, ease, and safety, are to be derived from dissolving it in a moist state. For this purpose, the pyroxyline is prepared in the usual way, and when rendered soluble by the addition of hydrocarbon solvents, it is taken out of the acids and placed in a hydraulic machine, by which as much as possible of the acid is expressed. The cake of pyroxyline is then taken out of the press, opened out, put into a centrifugal washing machine, and washed with water until clean ; then the rotation ef the machine is con- tinued, to throw out the surplus water. Or the pyroxyline, after con- version, may be placed in the centrifugal machine, and there deprived of the acids, and, without removal, be thoroughly washed, by admitting a copious supply of water, the operation occupying from a few minutes to an hour. When the pyroxyline does not contain more than 5 to 10 per cent, of water, it is dry enough for solution in naphtha, &c. 612 CELLULOID. Another improvement consists in mixing the pyroxyline and solvent, and combining the solutiou with oils and other matters, in a cylindrical vessel provided with a strainer or filter at the lower end, through which the materials are made to pass when sufficiently mixed and dissolved. Fig. 475 shows a side view, partly in section, of such a vessel. A strong cylindrical vessel a is mounted on wheels b suitable for running on a light tramway, and fitted with a metallic bottom a' perforated with small holes and covered with fine wire gauze. The moist pyroxyline is first mixed roughly with the solvent and other liquid with which it is compounded, and the whole is placed in a. When there, the materials are thoroughly mixed and beaten together, by means of a mechanical beater; this being completed, the mixing vessel is run into the press shown in side view in Fig. 476 : a is the cylinder of the press ; b, the ram, on the head of which is a frame 6'. and within it enters the receiving can c. When the ram rises, it receives the lower end of the mixing vessel d into a corresponding socket formed in it ; thus the mixing vessel is lifted to the piston e, which comes down upon the material in the former, and forces the whole of its contents, with the exception of the impurities, to pass through the perforated bottom into the receiving can c ; / is a projecting ring on the press head to prevent the ram rising too high. CELLULOID. 613 Fig. 477 is a side view of another mixing apparatus: a a is the frame of the apparatus ; on it is mounted the axis 6, which receives motion from a driving strap ; 6' is a bevelled wheel, driving two bevelled pinions c and d, mounted on tubular axes, turning in bearings on the frame. Within the axis of the wheel e, is another tubular axis e, caused to revolve with it by means of a groove and feather, and able to slide up and down vertically, through the axis of the wheel c; e' e' is a frame of beating bars fixed at the lower end of the axis e, and rotating with it ; / is another axis passing in a similar way tlirough the axis e, turning within it, and capable of sliding up and down within it ; this axis passes down through the axis e, and carries, at its lower end, the frame of beating bars//, which bars pass between the bars of the other frame e' as they revolve in opposite directions. The axes e and / are raised and lowered, so as to lift them out of the mixing vessel, or lower them down into it, by means of the hand wheel g mounted on the axis g' ; g" is a spur wheel at the upper end of the axis g' ; it drives another wheel h, mounted on a hollow axis carried by the frame. This axis has a screw thread cut in it corresponding with the screw , which works within it ; the lower end of the screw embraces the head of the axis / so as to cause it to rise and fall with it, but at the same time allowing it to rotate freely. In a similar way, the axis e at its upper end is made to embrace a collar on the axis /, so that when the screw rises or falls, the axes e and / with the beating frames upon them go with it. This machine is also very useful in mixing castor or other oil with chloride of sulphur, to produce a compound to be afterwards mixed with the preparation of pyroxyline. According to another plan, the pyroxyline, having been dissolved and mixed with the other ingredients, is kneaded, and the excess of solvent and moisture is evaporated in an apparatus of the following description. The mixture is put into a box provided with an air-tight cover, and containing a pair of rollers, which receive a rotary motion by suitable gearing on the out- side. The axles of the rollers enter the end of the box by air-tight joints ; they are hollow, and are arranged to admit of the passage of steam or other fluid for heating the rollers. To this box or vessel there is a pipe attached, to convey off the vapour of the solvent. In order to induce the passage of vapour from the box, a fan or exhausting apparatus is applied, which keeps up a partial vacuum, not only in the box, but also in the reservoirs containing the solvent, and in other parts of the apparatus connected with it. The vapour passing off from the box is first conveyed into a chamber in which there is a perforated partition, whereon chloride of calcium is placed ; through this the vapour rises, and any water is thus separated from the vapour of the solvent, which passes away from the cylinder to a condenser. The vapour of the solvent, on being condensed, passes into a reservoir. Fig. 478 is a plan, Fig. 479 a transverse section, and Fig. 480 a front view of the kneading apparatus : -a is the frame ; on it is mounted a hopper b, into which the material is placed as it comes from the press ; at the bottom of the hopper is a valve 6', which can be opened by hand when desired, to allow material to descend from the hopper to the rollers c and d, which are made hollow and heated with steam internally ; the roller c is driven by the spur wheels c' and c", the latter of which is fixed on a main driving shaft ; c'" is a pinion at the further end of the roller c ; it gears with a pinion d' of larger size on the end of the roller d, so that the rollers c and d are driven at different speeds, and have consequently a grinding action on the material passed between them ; e is a casing surrounding the rollers ; it is furnished with suitable doors, and is glazed at e' e', so 614 CELLULOID. that the workman may readily see what is going on within ; e" c" are apertures furnished with sleeves to allow the workman to introduce his arms within the casing c without causing any material escape of solvent vapour ; // is a collecting knife, set up to the surface of the roller c by the adjusting screws/'/. The 479. workman continually takes the material as it collects behind this knife, and passes it again between the rollers; he also collects the material from the table g beneath the rollers, and passes it repeatedly through the rollers, until it is thoroughly blended, and the solvent is suf- ficiently evaporated to bring it to the required consistence ; A is a pipe leading from the top and bottom of the casing, to conduct away any solvent or vapour of solvent which escapes from the mixture, to a cylinder containing chloride of calcium, and thence to a condensing ap- paratus. A fan maintains a partial vacuum in the casing, drying cylinder, and condenser, and so draws the vapour through the apparatus. The chloride of calcium cylinder separates the vapour of water which results from the moisture in the pyroxyline, and the condenser retains the solvent and delivers it back into a suitable tank. Instead of evaporating the solvent used in making the celluloid, it may be removed by precipi- tating the pyroxyline by means of water, mineral naphtha, &c. There is thus obtained a semi-solid mass, containing a small quantity of the solvent, which is passed through grinding rolls or other disintegrating machinery, and then worked up as usual. The celluloid is placed in a vessel con- taining a revolving agitator or beater, together with water or mineral naphtha in the proportion of CELLULOID. 615 1 lb. of celluloid to 1 qrt. of liquid, and the agitator is set in motion. After a short time, the cellu- loid is let out in a curd-like form, and submitted to pressure (not excessive), to separate the liquid. It is convenient to place it in a vessel of cylindrical form, and about 12 in. in diameter, provided with a movable and perforated bottom, covered with several layers of wire gauze. This is filled with the curd-like celluloid, upon which a plunger is forced down, and a cheese-like block is produced. This is rolled down between rollers heated by steam, as already described, and any pigment, &c., is worked in by them at the same time, the mixture being passed through and through till perfected. The solvent used is preferably mineral naphtha, as free from smell as possible. The solvent taken up by the liquid is recovered by distillation, if water has been used ; but in the case of naphtha, the greater part will separate on standing, and may then be decanted off. In order to make celluloid in imitation of pearl, fish-scales are mixed with the dissolved pyroxy- line, and a peurly-lustrous material is thus produced. To form a thin veneer of artificial pearl, one part of this material is mixed with 100 parts of pyroxyline. The latter is first ground with a solvent and oil to a doughy consistency, the pearly compound is then added, the solvent is separated, and the celluloid is worked up in the ordinary way. But when the celluloid is required in a semi-fluid con- dition, the solvent must be increased instead of removed, and a much larger proportion of the pearly material will be needed. The best lustre produced is that made in France, from the scales of the whiting. In producing a coloured celluloid, preference should always be given to dyes especially aniline rather than pigments. The brightest and most delicate colours may be imparted. To manufacture celluloid so as to resemble ivory, the following plan is adopted. The celluloid is made without any colouring matter, and is kept as clean and white as possible ; when in a dough- like state, it is rolled into sheets ^ i n . thick. Meantime another celluloid is prepared, containing carbonate of strontia in the proportion of one part to about 200 parts of pyroxyline, and this also is rolled into sheets. These sheets are placed alternately one over another to produce any desired grain. A good plan is to lay a transparent and an opaque sheet one over the other, and roll them up together, then take the roll and twist it, pass it through heated rollers and roll it down into a slab, for cutting knife handles or whatever may be required. In working white or light-coloured celluloids, or those in imitation of pearl or ivory, it is neces- sary that porcelain or glass vessels should be used in its manufacture as far as possible, and the rollers through which it is passed must be covered with platinum, as other metals are acted upon by the celluloid. A coating of platinum -fa in. thick will be very durable. For producing a white celluloid, without unduly increasing its specific gravity, the dissolved pyroxyline and other ingredients are mixed with white starch, either from wheat, rice, potatoes, &c., or with arrowroot, tapioca, or other amylaceous substance, or with wheat flour, or with cotton, ground and bleached. To remove the solvent remaining in the celluloid, which imparts a slight odour to articles made of it, and renders them liable to shrink in course of time, such articles are seasoned while in a partially manufactured state, by soaking them in a liquid which will dissolve out the solvent without affecting the pyroxyline, such as bisulphide of carbon, chloride of lime, or benzol. The articles so soaked are afterwards placed in a vessel from which the air is exhausted, and the curing liquid is thus drawn out, condensed, and recovered. The process employed for making billiard balls is as follows. To 100 parts of pyroxyline, dis- solved, ground, and strained as usual, are added 300 to 500 parts of the usual solvent alcohol 100 parts, naphtha 50 parts; 100 to 150 parts of arrowroot or starch; and 50 to 100 parts of the best zinc-white. The solid matters are added to the plastic solution of the pyroxyline, and the whole is placed in a closed rolling or grinding apparatus, the rollers being heated by steam as described, and the compound is ground up till most of the solvent is driven off. The latter is recovered by convey- ing it through pipes to a Liebig's condenser. The mass is now about as stiff as clay, and may be moulded or rolled, and placed in a warm place for seasoning. When well seasoned, the ball may be turned. When less specific gravity is required, it is best to employ as much amylaceous substances as possible, they being lighter than the zinc. Ground and bleached cotton fibre may be ground up with the plastic pyroxyline, in the proportion of 100 parts disintegrated cotton to 300 parts pyroxy- line paste. When making coloured celluloid with amylaceous substances or cotton, the colours should be added at the same time, and ground up with the other ingredients. Since the Paris Exhibition of 1868, where Parkes obtained a prize medal for his show of articles manufactured from celluloid, and where the substance was first named Parkesine, the Americans have made considerable advance in the manufacture. A modification worth mentioning consists in employing camphor as the solvent of the pyroxyline. The latter is first reduced to a fine pulp, by grinding it in water in a machine such as is used for grinding paper pulp, and to the pulp thus prepared, pulverized camphor gum is added, in the proportion of one part by weight of camphor to two parts pyroxyline when dry. At the same time, is added any desired material for colouring the celluloid, or modifying its specific gravity. The camphor is comminuted by grinding 616 CELLULOID. in water, trituration, or solution and precipitation. The camphorated mass is placed in a mould, and heated to a sufficient temperature to liquefy or vaporize the solvent, and is then subjected to heavy pressure. The temperature should never exceed 149 (300 F.), or the pulp in contact with the mould will become charred ; sometimes 66 (150 F.) suffices. The mixture should remain in the mould under heat and pressure till the conversion of the pyroxyline is completed ; it is then left to cool under pressure in the. mould. When first taken out, it has the consistency of sole leather ; but is easily softened by heat till the camphor has evaporated, when it grows aa hard as horn. For dental purposes, the transformation of the pyroxyline is effected by camphor, and without the use of fixed oils or fusible non-solvent gums, which are required to be combined with the material when ether, alcohol, &c., are used, and which would impair the strength, durability, purity, and firmness of texture essential in dental plates. Fifty parts at least by weight of camphor are added to one hundred parts of soluble pyroxyline; more camphor makes the compound more plastic. The plates formed are placed in a drying room heated to 65-82 (150-180 F.), the latter being the maximum, to drive off the camphor. A temperature above 93 (200 F.) will expand the material, and make it porous and brittle. It is said that this compound is lighter and stronger than dental vulcanite or indiarubber ; its colour is the same as the natural gum, and is unchange- able ; it has no unpleasant taste ; it is absolutely non-injurious, and never shrinks or warps after setting. The following process is adopted in practice to dissolve the pyroxyline in camphor, eliminate the solvent, and form a solid mass of celluloid at one operation. The prepared mixture of soluble pyroxyline and camphor is first dried, by compressing the moist, pulpy compound into conve- nient sized cakes, about \ in. to 2 in. thick, and arranging them in a pile with intermediate layers of paper, or other absorbent material, and subjecting the pile to pressure in a hydraulic press. By this means, the material is uniformly and sufficiently deprived of its moisture, while the com- pression of the material and exclusion of the air prevent all danger of ignition when exposed to the enn or the heated air of a drying room. The mixture of pyroxyline and camphor is subjected to pressure by means of a plunger in a heated cylinder provided with a discharge nozzle or pipe, the cylinder being of sufficient length to cause the conversion of the pyroxyline to take place while the material is being gradually forced through it, so that by replenishing it as it becomes partially empty, a gradual discharge of the celluloid is effected, in the form of a continuous bar or sheet as desired. The cylinder is unequally heated, in such a manner that the mixed material will first be compacted in the colder portion, before the solvent is melted and the process of transformation commences. The air is thus allowed to escape more freely, and is more completely expelled, while the conversion of the pyroxyline is effected in another and hotter portion of the cylinder, as the mass is forced through it. The upper or receiving end of the cylinder is cooled by being surrounded by a cold-water jacket ; and the lower or discharging end is heated by a steam or hot- water jacket. The former is supplied by the escape pipe of the hydraulic engine. In the discharge end of the converting cylinder, is a central heating and distributing case, constructed with radial pins or projections, by which the material, before it escapes from the cylinder, is caused to pass through the annular space around the central core, and in contact with the heated surface of the cylinder, while the spurs or pins divide and mix the material, and at the same time serve to conduct the heat from the cylinder to the central core. The discharge pipe is passed through an equalizing warm-water vessel, which keeps it sufficiently warm to prevent the material in contact with the inner surface cooling faster than the central portion, as the unequal cooling, and consequent unequal consistency, of the different portions of the material would cause the central and softer portion to move faster than the outer and harder portion, tbua destroying the homogeneity of the mass, and rendering the surface rough and broken. The soluble pyroxyline is first comminuted in a wet condition, and the excess of water is pressed out. The camphor and colours, as required, are then thoroughly incorporated with it by the mixing rollers. The compound, thus prepared, is formed into cakes by means of a mould and follower, the bottom of the mould being made separate, and serving to transfer the formed cake to the pile. These cakes are preferably made about 12 in. square, and J to J in. thick; it would be difficult to properly absorb the moisture from thicker cakes. These are laid up in a pile with layers of blotting-paper between them, and are then placed in a hydraulic press to remove the water as far as necessary. During this process, the compound is protected from the air, to prevent evaporation of the camphor, and to avoid the chance of ignition. The rapidity with which this drying is effected ensures great saving of time and space. The dried material is ready for conversion into celluloid, for which purpose, it is transferred, with the solvent, to the converting cylinder. The heat from the steam-jacket surrounding the lower portion of this cylinder brings about the conversion of the pyroxyline to a homogeneous mass of celluloid, which is then forced through a discharge nozzle, constructed according to the desired form of the product, e. g. in bars or sheets, or directly into a mould of the article to be manufactured. CELLULOID. 617 The use of various solvents and combinations of solvent materials has been attempted or proposed; e.g. a mixture of camphor and oils in about the following proportions, viz. : Camphor, camphor oil, or liquid camphor 20 parts by weight. Oil, such as castor or linseed, before or after boiling . . 40 Pyroxy line (soluble) 40 These will give a consistency suitable for covering telegraph wires, or for moulding or spread- ing. For material with greater or less flexibility, or greater or less fluidity, the proportion or character of the oil must be changed. In producing very hard or rigid material, it is preferable to use oils which will themselves harden by exposure to air, as those which have been boiled. Camphor may also be used in about equal proportions with hydrocarbons having a boiling-point at 104-204 (220-400 F.) ; or with alcohol or spirits of wine ; or hydrocarbons in equal proportions with alcohol ; or castor oil in equal proportions with alcohol ; or a distillate of a mixture of camphor oil and hydrocarbons, or of camphor and bisulphide of carbon in conjunction with alcohol; or aldehyde, either alone or with alcohol. Either of these solvents may be employed with the other ingredients in about the following proportions, to produce a semi-fluid celluloid : Pyroxyline (soluble) 27 parts by weight. Castor oil 27 Camphor 6 Either of the foregoing solvents 40 The consistency will depend chiefly on the proportions of the oil, as before. The most recent and valuable improvements in the manufacture of celluloid, for all manner of purposes, will be found in two patents (Nos. 1865 and 1866) taken out, in May last, by Henry Parkes, a relative of the first European discoverer of the substance. Uses. It is only fair to premise that, in the following sketch of some of the applications of celluloid, no pretence is made to exhaust the list. It possesses such a combination of valuable properties that its sphere of usefulness must of necessity be enlarged, as the article becomes more generally known and appreciated, and as further steps are made in the direction of controlling its rather combustible tendencies under climatic changes. Nevertheless, it will be seen from the sequel that it has already attained a high degree of importance. It is superior to ivory on the score of durability, as it sustains hard blows without injury, and never loses its colour. One whole company in the United States employ it exclusively for organ and piano keys, and its con- sumption for that and similar purposes lias assumed such proportions that ivory is much- reduced in price in consequence. Billiard balls can be made from it at half the cost of ivory, while possessing equal elasticity and greater durability. It is extensively employed for making combs, brush backs (see Brushes), and various other toilet things wherein ivory has hitherto been used. For small-tooth combs, the cost is 25 per cent, less than ivory, and in large pieces, the difference is enormous. It effectually displaces ivory, too, in harness trimmings, foot-rules, chessmen, and handles of various kinds, especially knife and fork handles, for which purposes it is admirably adapted, as it neither cracks nor becomes discoloured by hot water. Indiarubber generally holds its own in competition with celluloid, on account of the relative prices ; but the latter is much more durable, and is superior for pencil-cases, jewellery, &c., where gold mountings are used, as it does not tarnish the metal, whereas the sulphur in indiarubber tarnishes all gold under 18 carat. This freedom from sulphur, and the readiness with which it takes a natural flesh-tint, have caused cellu- loid to be used for dental blanks or gum, and other attachments of artificial teeth, in lieu of vulcanized indiarubber. It can be mottled to imitate the finest tortoiseshell, and its elasticity renders it less liable to fracture. In this form, it is much used for combs, card and cigar cases, match-boxes, pocket-books, napkin-rings, and all sorts of fancy articles. It can be made to resemble malachite and amber equally well, and is very suitable for the mouth-pieces of pipes, cigar-holders, flutes, flageolets, &c. For drum-heads, too, it is better than parchment, as it is not aflected by moisture. It replaces porcelain in the manufacture of dolls' heads, which are practically unbreak- able. Coral of all shades can be copied exactly, but dark or bright red, and not the rare and costly delicate pink shade, are mostly in demand. For optical goods, such as the frames of spectacles, eye and opera-glasses, it competes successfully with jet, tortoiseshell, &c. ; and for photographic purposes, it is superior to ivory. It is used for shoe-tips instead of metal, and has the appearance of patent leather ; it is also employed in in-soles. Many thimbles are made of it ; and it is said to be the best material known for emery-wheels and knife-sharpeners. Within this last eighteen months or so, a new demand has arisen for the substance, as a substitute for linen or paper in shirt-fronts, cuffs, and collars. It looks like well-starched linen, is sufficiently light and flexible, does not wrinkle, is not aflected by perspiration, and can be worn for months without injury. It soils less readily than linen, and, when dirty, is quickly cleaned with a little soap and water on a flannel. A more recent improvement consists in placing real linen between two sheets of celluloid. It has also been 618 CEMENTS. tried for neckties. For hatbands and hat sweat-bands, it is dearer than the articles in present use ; but it is much superior, as it does not become rusty or greasy. As yet the teats of manufacture are exceedingly few, principally owing to the fact that almost all the details of the manufacture are the subjects of patents, which are the property of only one or two individuals. All the celluloid produced in the United States, where the manufacture and application of the substance have received the greatest impulse, is turned out by one firm at Newark, in New Jersey. There is one works in Fiance, at Staines, on the Seine, but beyond that there is none in Europe. A company instituted in England failed through constitutional detects, and a works- started by a Hanover firm was abandoned because of the explosive nature of the material. If greater energy be not soon displayed in England, we shall probably become importers of the substance, first discovered and manufactured in our own country, by A. Parkes, so long ago as 1855. Though the invention is thus of no recent date, the manufacture has only been developed within the last few years. The commercial price of the article in France is 8 francs per kilo, (about 2s. Wd. per Ib.) for the raw product, and variable for coloured sorts. In America it sells at 2 dollars (8s. 4d) per Ib. for muking umbrella handles, &c., while the same substance is charged at 4 to 5 dollars to jewellers, the price being adjusted according to the competition experienced from the various substitutes. The American firm is concerned only with the manufacture of the raw material, which it supplies in blocks to the consumers, who have to prepare it according to their special needs. It is said to be exported largely to Cuba and South America. Vulcanized Fibre. Under the name of "Vulcanized Fibre," an American firm, whose works are at Wilmington, are producing a material much resembling celluloid in its origin and applications. It is prepared from a thick, spongy, reddish-brown paper, specially made for the purpose, which, when acted upon by certain chemicals, loses its original character, and is trans- lormed into a homogeneous mass of almost metallic hardness. The material emerges from the process of manufacture in large flat sheets, which are made up into a long list of articles, principally for railway use, as fish-bolt washers, oil-box covers, " dust-guards," &c., &c. The company, it is said, sells nearly a quarter of a million track-bolt washers a month. An important application of the substance is for the manufacture of condense-pipes for steamers ; exposure to the action of salt water, and alterations of temperature, do not seem to affect it in any way. From the scraps left in zutting large articles, carriage-washers are made. Roving-cans, used in cotton-mills, and formerly made of tin, are now made of this material. As yet, it has not been largely applied to making ornamental articles ; but its finish makes it well suited to such purposes. It cannot be moulded, but may be sawn, cut, or turned ; is capable of receiving various colours, and is used in both the polished and unpolished state. (See Brushes ; Buttons ; Ivory ; Nuts.) CEMENTS. (Fn., Ciment ; GEB., Cement.) A cement is a substance, which, on being applied to the surfaces of two bodies, causes them to adhere strongly, when brought into contact. For the purposes of easy reference, a system of classi- fication will be adopted in dealing with this subject, the subdivisions being Calcareous cements, Gelatinous cements, Glutinous cements, Resinous cementing compounds, and Non-resinous sementing compounds. These will be followed by a number of compositions often erroneously termed cements, but more properly designated Lutes. Calcareous Cements. Though comparatively few in number, these are by far the most important cements. Their ingredients are all obtained from the mineral kingdom, and their efficacy depends chiefly upon the treatment of the raw materials, and the proportions of their admixture. The principal varieties are the following : Mortar. Mortar is composed of two essential ingredients, lime and sand, which are intimately mixed, in a fine state, by the agency of water. The sources of lime, in this country, are very abundant. It is obtained from the crystalline marbles of the Metamorphic system; from the coralline and shelly beds of the Silurian ; from the cornstones of the Old Red Sandstone ; from the coralline and shelly marbles of the Devonian ; from the coralline, encrinal, shelly, and fresh-water beds of the Carboniferous ; from the dolomites of the Permian ; from the muschelkalks and gypsums of the Trias; from the oolites of the Jurassic: from the shelly bands of the Wealden ; from the chalks of the Cretaceous ; from the gypseous and nummulitic strata of the Tertiary ; from the lacustrine marls of the Post-Tertiary. In composition, these rocks vary considerably, some being essentially carbonates, others sulphates, others again magnesian or dolomitic ; further, these may be argillaceous, bituminous, ferruginous, or siliceous. The limestones best suited for the manufacture of common mortar are carbonates which are free from silica, alumina, and iron. These, after being quarried, and broken into pieces of a convenient size, are calcined in kilns constructed in a variety of ways. The kiln should be placed as near as possible to the quarries whence the stone is extracted, so as to avoid carriage. The longer the stone CEMENTS. 619 has been exposed to the air, the less fuel will be consumed in driving off its inherent moisture, or " quarry water." Generally, ordinary pit coal is used in the calcination, one ton being necessary for every 4 or 5 tons of limestone ; for some kinds of stone, however, slaty, or shaly coals, are better adapted than superior coal, not only from their being cheaper in price, but also because they burn the stone more slowly and equally, at the same time keeping it " open," and preventing its slagging and sintering. These impure coals may cause a greater amount of kiln-dust ; but the lime will be more free from cores and slags. When properly burnt, that is to say, when not slagged or coated with a siliceous glaze, from too sudden ignition, the limestone will have lost its carbonic acid, and will have become converted into caustic or " quick'' lime, protoxide of calcium. One hundred parts of raw limestone should yield fifty-six parts of quicklime. The proper selection of the sand has as great an influence upon the mortar as has the character of the lime. The " sharper " and cleaner the sand, the better ; the finest mortar is made with clean pit or river sand ; the presence of earthy impurities will interfere with the chemical union of the lime and silica ; sea sand is sure to be impregnated with salt, which will subsequently cause deliquescence or efflorescence. Before mixing the lime and sand together, to form mortar, the former must be " slaked " with water. One volume of water ia added to three volumes of lime, when the latter " falls down," with violent evolution of heat, into a powder, whose colour will resemble the tint of the limestone employed. The more rapidly and completely it falls, the better the lime ; a lime that falls slowly and unequally will never be satisfactorily cohesive. When the lime is slaked, more water is applied, to convert it into a pulp or paste ; this paste, thoroughly incorporated with an equivalent of sand, constitutes common mortar. The proportion of sand will vary with the richness or " fatness " of the lime, which latter is dependent upon the purity of the original carbonate of lime ; for poor limes, 2 or 2J parts of sand will suffice, while some fat limes will take 4 or 5 parts, and yield a superior mortar. The longer a lime remains slaked before being used, the stronger will be the mortar made with it. The admirable solidity of ancient buildings is entirely due to the fact that the slaked lime was covered with turf, and kept for a year, often even three years, before use. It is scarcely necessary to remark that mortar is distinguished from hydraulic cements, by its incapacity to set, or harden, under water. Hydraulic limestones, or those which yield a lime capable of setting under water, are not so abundant as ordinary limestones. The blue Lias, stretching from Whitby, on the north-east, to Lyme Regis, in the south-west of England, is the chief source. Available beds, which have been igno- rantly regarded as " bastard " limestones, and therefore neglected, occur among the Carboniferous limestones of Flintshire, Northumberland, Lanarkshire, East Fife, and the Lothians. These may always be distinguished, according to Dr. Page, by their tougher, earthier, and less crystalline texture, by not effervescing so violently under acids, and by weathering more slowly into a deeper brown surface. Some of the argillo-calcareous ironstones, known as " curl," and " cone in cone," and containing about 10 per cent, of iron, are used, as at Coalbrookdale, in the manufacture of hydraulic cements. The Septaria, or argillo-calcareous nodules, of the London clay and lower Lias, are well known for their strong and energetic hydraulic qualities. Recently, the beds of exceed- ingly pure gypsum, disclosed by the sub-Wealden borings, have been drawn upon by cement- makers. There are some scores of hydraulic cements in the market ; but their composition varies rather in method and proportion of admixture, than in the ingredients themselves. The essential com- ponents are lime, clay, and oxide of iron ; the lime may vary from 50 to 80 per cent. ; the clay, from 25 to 40 ; and the oxide of iron, from 3 to 14. In some cases, the limestone employed is naturally hydraulic; but more often, that quality is attained by an artificial admixture of the required materials. The following are some of the best-known hydraulic cements : Parker's. This cement is made from the nodules of indurated and slightly ferruginous marl, known as Septaria, belonging to the London clay, and found in the Isle of Sheppy, at Harwich, and on other parts of the south-eastern coast. These, as well as the argillo-calcareous nodules from the lower Lias, are naturally hydraulic limestones ; when well selected and prepared, they furnish a quick-setting, strong, and durable cement. They are burnt with pit coal in conical kilns, in the same manner as other limestones, care being taken to avoid excessive heat, as, if the lumps undergo the slightest fusion, even on the surface, they will be unfit for cement-making. After proper roasting, the calx is ground to very fine powder, and immediately packed in barrels, to exclude air and moisture. For use, it is tempered with water, and applied at once ; it soon hardens, and will not bear being softened down again with water. Pew's. Quicklime, 1 part; baked clay, 2 parts; powdered, mixed, and calcined; then, gypsum, fresh baked and in fine powder, 1 part, is added to powdered baked clay, 2 parts ; mixed well, added to the former compound, and the whole thoroughly incorporated. It is very hard and durable. Portland. This cement, so largely manufactured on the Thames, the Tyne, and other rivers, 620 CEMENTS. consists of about 80 parts of chalk or rich lime, and 20 parts of fluviatile mud, or clay ; the two ingr dients are incorporated wet, then dried, calcined, and reduced to powder. Homan. Genuine Roman cement is manufactured from pozzuolana, a ferruginous volcanic ash from Vesuvius and other Italian volcanoes, and lime ; or, from a combination of lime and a Tertiary volcanic earth, or kind of pumice, called trass, which occupies wide areas in the Eifel district of the Rhine. The only preparation required is grinding to an impalpable powder. The Roman cement made in this country is obtained from the Septaria of the London clay and the lower Lias, from the cement stone of the upper Lias, and from the shale beds of the Kimmeridge clay ; it is also manufactured from several artificial admixtures of lime and ferruginous clay, calcined together. It must be kept in closed vessels, and is mixed with water for use. For further information on the subject of Calcareous Cements, the reader is referred to Spons' ' Dictionary of Engineering,' and Supplement ; to Reid's ' Cement ' ; and to Page's ' Ecouomic Geology.' Gelatinous Cements. All animal tissues contain an adhesive substance, which anatomists call " histose." When the tissues are boiled in water, the histose is changed into a substance called " gelatine," which is dissolved by the water. It may afterwards be separated from the water by simple evaporation, when it forms a dry, hard substance, which has different names according to the source from, which it has been manufactured. That obtained from cartilage is called " chondrine " ; that from bones, hoofs, and hides, "glue"; that from the air-bladders and intestines of fishes, " isinglass " ; and that from the less tenacious and adhesive constituents of parchment scraps, and some other animal membranes, " size." The process of manufacture, in all these cases, consists in boiling in water; the hot water causes the animal substances to change into gelatine, which it dissolves. (See Bones.) Of the products mentioned above, two only are employed as cements, viz. Glue, and Size. Glue. This useful article is made from fresh bones, freed from fat by previous boiling ; from the refuse scraps produced in trimming skins for tanners ; from the hoofs and horns of cattle ; and from leather cuttings. The best glue is obtained from the " soundings'" of sheep-skins and cattle-hides, known as " fleshings," and also, from their industrial application, as " glue-pieces." These are first placed in pits containing milk of lime, where they are allowed to soak for several days, or even three weeks; the milk of lime is changed every six or seven d;iys, and the pieces nre occasionally turned over. When sufficiently 'soaked, the pieces are taken out to drain and dry, for which purpose they are placed on hurdles, or in layers on a sloping pavement, and turned over three times daily. When dry and hard, they are ready to be sold to the glue-manufacturer, and are a better material for his purpose than the fresh skin-pieces. The first operation of the glue-maker is to soak the pieces in weak lime-water, and then to wash them in baskets under a stream of water. They are then drained, and exposed to the air, so as to enable the adhering lime to absorb carbonic acid from the atmosphere, and thus to lose its caustic properties, which would destroy part of the glue during the subsequent boiling operations. Glue which is to be used as gelatine, for culinary purposes, is derived from perfectly clean and fresh bones. For the manufacture of this material, beef-bones are preferred to all others, as they yield a perfectly transparent article, sold under the name of gelatine or isinglass. Calf-bones give a milky glue ; hog-bones create a blackish foam in the solution ; while the product from sheep-bones always retains the peculiar odour of the fat of these animals. The glue made from hoofs and bones is always brown and of common quality. Whatever the substance used, whether glue-pieces, bones, or horns, the process is essentially the same. The raw material is put into a flat copper boiler, provided with a perforated false bottom, at a little distance above the bottom, so as to prevent the solid material from touching the shell, where it would stick fast and be burned. The boiler is two-thirds filled with water, and heat is applied. In a few hours, after stirring repeatedly, the pulpy liquid is drawn off in successive portions, as soon as it is perceived that a sample taken out gelatinizes on cooling. Experience has taught that too long boiling injures the glue. The test for this cooled gelatinized material is that it must be fit to be cut into slices with a wire. Before drawing off the solution, the fire is let down, so as to stop the boiling, and allow the liquid to clarify by settling. The liquor is then drawn off into a deep boiler, where it settles for the second time, remaining hot for from five to six hours- The longer it stays in this vat, the better it will be clarified, and the higher will be its market price. Often a certain proportion of alum is added to it at this stage, to assist the separation of the impurities. From the vats, the warm liquid is run into shallow, flat coolers, consisting of wooden boxes, about 14 ft. long, 12 in. wide, and 9 in. deep These are placed in a cold situation, BO that the liquid may cool and gelatinize. This operation occupies from twelve to eighteen hours, according to the state of the weather ; at the end of this period, the glue will be sufficiently firm to be taken out as an elastic cake. For this purpose, the wooden boxes are inverted on a moist table, and the mass of glue is then divided into a series of blocks, or " gobbets " ; these blocks are next placed in a wooden frame, 12 in. by 7 in. by 6 in. deep, and provided with about a dozen slits, the whole much CEMENTS. 621 resembling a set of school-slate frames placed together. Each block is then cut horizontally into slices, by means of a brass wire stretched like a bow-saw on a frame, and inserted in the slits of the frame containing the block. The slices, thus cut, are laid out on sheets of galvanized iron wiie netting, exposed on every side to the air, for the purpose of drying and hardening. This part of the manufacture is most exposed to the risks of possible failure, by reason of the influence exerted by the weather. A sudden heat will soften the glue, so that it will run through the nets; moist weather will prevent the drying, and, if it is warm at the same time, the glue may be so spoiled, and acquire such a bad odour, as to be fit only to be thrown away ; a fog, or a thunderstorm may spoil the operation, and render all the previous trouble and expense totally useless. Glue which has once manifested a bad smell during the process of manufacture, even though dried afterwards to a perfectly odourless solid, will reveal its quality when dissolved at any subsequent period ; nay, while still dry in the barrel, it will become disagreeably odorous on every moist day ; and, what is worse, walls on which this glue has been used will give out the smell in damp weather. As a matter of course, such glue loses much of its commercial value. In the course of drying, the slice of glue shrinks until its size is only half of what it was when in a moist state ; and it requires to be carefully watched and turned, to prevent uneven contraction, which would cause it to split. After being dried, the slices are taken into sheds, and washed with boiling water, for the purpose of removing any dirt or dust, which may have adhered to their surface in the course of drying. The glue is then packed ready for the market. The qualities commonly made are " town glue," worth about 6d. a Ib. ; " strong Russian dark," Qd. ; " finest kid," Is. When glue-making is properly conducted, there should be no waste product. The large bones, after boiling, may be sold to the button manufacturer (see Bones, and Buttons) ; the small bones are valuable for making bone black (see Blacks), or for their fertilizing properties (see Manures) ; hoofs are useful for making combs ; hair from the u fleshings " has many applications ; the waste lime from the pits is an excellent manure. A great improvement in the method of conducting the manufacture of glue is the application of superheated steam to the materials, by which a much larger proportion of glue is extracted, in a shorter time, and at less cost. Another improvement is the addition of Paris white (fine chalk) to the glue used by cabinet-makers. It has the following advantages : 1. It increases the adhesive qualities of the glue. 2. It makes the glue look whiter, and thus gives to a browner glue, the lighter appearance of a more expensive quality. 3. It is a pecuniary gain, since a substance costing only 1 d. or 2d. a Ib. is added to one costing Is. 3d to Is. 8d. ; but it is not to be considered as a common adulteration : the buyer loses nothing, as the price is proportionally reduced, while the quality is improved. This is an American plan, and explains the milkiness of the glue made in the United States. A novel feature in glue manufacture is the utilization of leather refuse for the purpose. Old leather, or leather refuse, is subjected to the action of 15 per cent, of a mixture of slaked lime and water, in closed vessels, at a temperature of 121 (250 F.). In this way, the leather is completely decomposed. Its principal constituents being tannic acid combined with gelatine, the tannic acid attacks the lime, forming tannate of lime, while the gelatine is set free, and is dissolved in the water. The high temperature required for the operation injures the glue, which is undoubtedly somewhat deteriorated by the previous action of the tannin on the leather from which it is derived. For these reasons, the glue obtained from leather is inferior in its adhesive qualities ; but it may do very well for culinary purposes. The Laplanders make an excellent glue from the skins of perches ; and it is probable that eel- skins would serve the same end. The largest skins are chosen, and dried ; they are then moistened with cold water, till they have become so soft that the scales can be separated ; the latter are thrown away. Four or five of the skins are then put into a reindeer's bladder, or wrapped up in the soft bark of the birch tree, in such a manner as to exclude water. Thus covered, they are placed in a pot of boiling water, and kept at the bottom by means of a stone. After boiling for about an hour, they are uncovered, having, by that time, become soft or viscous. In this state, they are employed for joining the two pieces of the Lapp bows ; if pressure be exerted till the glue is quite dry, the joint will never give way. Good glue should be hard, and difficult to break with a hammer, though, when broken, it should yield suddenly to the force, and present a sharp vitreous fracture. It must be admitted, however, that some very fair glues, in thin pieces, will yield or bend a little, even when quite dry, before breaking. The colour, whether dark or light, should be bright, not too dark, and without any green tint. The substance should be transparent, and free from foreign particles, and should be capable of absorbing a considerable quantity of water, say, at least four to seven times its own weight. Generally speaking, the amount of water thus absorbed will serve as an indication of the quality of the glue, provided that the resultant mass is not too friable, and remains clear, or nearly so, and that when it has been melted and allowed to cool, the jelly it forms is tolerably clear and fresh, and not liable to rapid spontaneous putrefaction. From careful experiments made with dry glue, 622 CEMENTS. immersed for twenty-four hours in water, at 15 (60 F.), and thereby transformed into a jelly, it was found that the finest ordinary glue, or that made from white bones, will absorb twelve times its weight of water in twenty-four hours ; that glue from dark bones will absorb nine times its weight of water ; while the ordinary glue made from animal refuse will absorb but three to five times its own weight of water. One of the best chemical tests of the quality of glue is to ascertain the proportion of pure gelatine in the mass. This may be done by means of a solution of binitrate of mercury, in water acidulated with nitric acid. The test should be compared with a solution containing a known amount of gelatine. The usual chemical test to distinguish the presence of glue in any liquid is tannic acid, which forms, in a solution of any kind of gelatine, a copious leathery precipitate, of which the particles, however, cannot be made to adhere together like leather, the fibrous structure of the " histose," from which the gelatine is derived, being absent. The imports of glue and glue clippings into the United Kingdom, in 1870, were 30,293 cwt., valued at 36,046/. ; and the exports were 2439 cwt., valued at 4937f. Liquid Glue. (a) Ordinary glue, 5 lb., is dissolved in water, contained in a vessel which may be heated by means of a water bath, care being taken to stir from time to time. When all the glue is melted, 1 lb. of commercial nitric acid is gradually added in small doses. This addition creates an effervescence, and a disengagement of red nitrous fumes. When all the acid has been poured in, the vessel is withdrawn from the fire, and the contents are left to cool. This glue may be kept for a long time, even in uncorked vessels. It is used cold, by means of a brush. It may also be employed as a lute, by spreading it on strips of linen. (6) Ordinary glue, 100 oz., is dissolved in a water bath with 250 oz. vinegar ; when the whole has become liquid, 250 oz. ordinary alcohol, and 10 oz. alum are added, the mass being kept over a fire for a quarter of an hour. It is very tenacious, and does not become putrid. When too thick, a little water may be added, and the mixture may be heated. It is very useful for cementing, in the cold, a variety of small objects, and is much employed by the makers of false pearls, (c) Four parts by weight of gelatine or ordinary glue are dissolved, in the cold, or better, at a gentle heat, in ten parts of commercial acetic acid, (d) Glue in fine pieces, 6 parts, macerated for some hours in water, 16 parts, adding hydrochloric acid, 1 part, and sulphate of zinc, 1 part ; the whole is then exposed, for ten to twelve hours, to a temperature of 80 or 90 (176-194 F.) ; the mixture will keep unaltered for a long time. Parchment Glue. Parchment, 10 parts, is cut into small pieces, and boiled in 128 parts of water, until the liquid is reduced to 80 parts. The decoction is filtered through linen, and evaporated over a gentle fire, until it presents the desired consistence. Size. A recently introduced size which, for the paper-maker's purpose, is said to be 50 per cent, cheaper and much better than the ordinary size, is made in the following way : In a copper pan heated by steam (waste steam will do) from 45 to 50 lb. of soda is dissolved in 200 to 240 lb. boiling water ; while still boiling, 300 lb. powdered rosin is added, and thoroughly stirred in till it is entirely dissolved, an operation generally requiring three to four hours. This soda-rosin compound is dissolved in water, in the proportion of 1 lb. of the former to 30 to 40 lb. of the latter ; it is then thoroughly incorporated with a glue solution, made by dissolving 100 lb. glue in 300 to 400 lb. water. The two solutions are then boiled together for about ten minutes, after which the mixture is run through a fine sieve or filter, and is then ready for use. The best proportions for mixing the vegetable and animal sizes are, for 1J part of rosin, 1 part of glue; for some purposes, equal parts of each may be taken. The addition of starch, if required, can be made as usual. Waterproof Glue. In order to render glue insoluble in water, even hot water, it is only necessary, when dissolving the glue for use, to add a little bichromate potash to the water, and to expose the glued part to light. The proportion of bichromate will vary with circumstances ; but for most purposes, about -^ of the amount of glue used will suffice. Glutinous Cements. By glutinous cements, are understood those whose base is a substance containing a large proportion of gluten, such as the flour of wheat, rye, rice, $c. They are com- monly known as " paste," of which the chief varieties are the following : Japanese Paste. The Japanese make a very fine paste from rice flour. The flour is mixed with a little cold water, and into it is gradually poured boiling water, till the mass has attained the proper consistence ; it is then boiled for one or two minutes. It is beautifully white and trans- parent, as well as very strong, and is consequently well adapted for fancy work requiring a colourless cement. Ordinary Paste. There are two distinct ways of making ordinary household paste : (a) About a tablespoonful of wheat flour is mixed in a saucepan with say | pint of cold water, the latter being added gradually and thoroughly incorporated by continual stirring ; the vessel is then put on the fire, and the contents are unceasingly stirred till they boil, great care being necessary to prevent their caking or burning on to the pot ; (6) The water is first heated to boiling, and the flour is then added with constant stirring; to prevent the formation of lumps, the flour may be passed through a CEMENTS. 623 sieve, so as to ensure its more equable distribution ; agitation is continued till the heat has rendered the mass of the desired consistence, and, after a few moments' further boiling, it is ready for use. To preserve paste from the attacks of insects, and to arrest its decomposition, it is well to add a small quantity of some antiseptic material, e. g. a few drops of carbolic acid, or oil of cloves, er a Jittle powdered corrosive sublimate, camphor, or colocynth. Thus treated, and placed in covered vessels, it will keep fresh for years. The addition of salt or brown sugar has a similar effect in a minor degree. Paste which has become hard or dry may be softened by beating up with a little hot water. With the object of considerably increasing the strength of paste, bookbinders, paper- hangers, and shoemakers usually acid powdered rosin to the flour, in the proportion of A, or even J, of the weight of the latter; it is then known as " hard paste." Sometimes a teaspoonful of alum is introduced into each 1 pint of water, for the same purpose. Starch Paste. The best method of preparing starch paste is as follows. The starch is saturated with cold water in a mortar, to produce a thick paste free from clots ; into this, is then poured a small stream of boiling water, till " starch " commences to form, which is recognized by the mixture becoming transparent ; the remainder of the water is then added, the total requisite quantity being twelve to fifteen times the weight of dry starch used. Heating the mass is useless. The addition of a little alum to the water helps to preserve the paste. Cementing Compounds. The cements hitherto considered may be called simple, in con- tradistinction to the multifarious compounds which have now to be described. In the former, the adhesive virtue of one or more simple solid bodies is brought into play by the application of water, or heat, or both ; into the latter, is introduced a great variety of substances, some possessing cementing qualities, others serving only as carriers of the preceding, or as driers. These compounds may be very conveniently divided into two classes, to be called respectively " resinous," and *' non-resinous." a. Resinous. Under the term " resinous cementing compounds," will be included all those preparations which owe their cementing properties to the presence of a resin, gum-resin, or gum, such as common rosin, indiarabber, guttapercha, gum arabic, &c. Compounds of this class are numerous, the best known being the following : Bottle-corks, for. The black bituminous cement used for bottle-corks consists of pitch, hardened by the addition of brickdust and rosin. Chinese. (a) For wood, glass, ivory, jewellery, and all fancy work : finest pale-orange shellac, broken small, 4 oz. ; strongest rectified spirit (58 O.P.), 3 oz. ; digested together in a corked bottle in a warm place till dissolved, when the mass should have the consistence of treacle. This is one of the best cements for repairing glass, china, &c. It is so strong \hat pieces of wood cut obliquely across the grain and joined by it cannot be made to part at the juncture. Throughout the far East, it is used in joining bows, arrows, &c. ; the fluid is smeared over the faces to be joined, a piece of very thin gauze is interposed, and the whole is pressed tightly together and thus left till the follow- ing day. Joints made with it will resist even the continual bending of a bow ; it is invaluable for mending fishing rods, and similar articles. (6) Clean glass is reduced to a very fine powder, and passed through a silken sieve; the powder is ground with white of egg on a stone slab, powdered glass being added till the required consistence is attained. It forms a very firm cement for glass and porcelain, vessels repaired with it breaking in a new place rather than at the joint, (c) IShelluc, 3 oz. ; borax, 1 oz. ; water, f pint ; the whole is boiled in a covered vessel till dissolved, then evaporated to the proper consistence. It dries slowly, but is cheap and useful. Druggists and oilmen often employ it instead of gum, for fixing paper labels to glass or tin, where exposed to damp. Cutlers'. For fixing blades of knives in their handles, the hank of the blade is heated and pressed into the hole in the handle, which has previously been filled with one of the following compositions : (a) Ros-in, 4 parts ; beeswax, 1 part ; and brickdust, or plaster of Paris, 1 part ; (6) Rosin, 16 parts; hot whiting, 16 parts; and wax, 1 part; (c) Pitch, 4 parts; rosin, 4 parts; tallow, 2 parts ; and brickdust, 2 parts. Elastic. Bisulphide of carbon, 4 oz. ; indiarubber in fine shreds, 1 oz. ; isinglass, 2 drachms ; guttapercha, -J- oz. ; dissolve. Used for joining leather or indiarubber. The parts must be thinly coated with the solution, which is left for a few minutes to dry, and then heated to melting ; the parts are placed in close contact, and the air-bubbles are well hammered out. Electrical or Chemical Apparatus, for. (a) A good cement for connecting the parts of chemical or electrical apparatus may be made by mixing 5 Ib. rosin. 1 Ib. wax, 1 Ib. red ochre, and 2 oz. plaster of Paris, and melting the whole with moderate heat. (6) Black rosin, 7 Ib. ; red ochre, 1 Ib. ; plaster of Paris, | Ib., well dried, and added while warm; then heated to a little above 100 (212 F.), and agitated together, till all frothing ceases and the liquid runs smooth ; the vessel is then removed from the fire, and the contents are stirred till sufficiently cool for use. Grinders'. (a) Pitch, 5 parts ; wood ashes, 1 part ; hard tallow, 1 part ; melted together. (6) Black rosin, 4 Ib. ; beeswax, 1 Ib. ; melted ; to these is added whiting, previously made red hot, 624 CEMENTS. and while still warm, 1 Ib. These are used for fixing pieces of glass, &c., while grinding, (c) Shellac, melted, and applied to the pieces slightly warmed. Used for lenses and fine work. Gum. An aqueous solution of gum arabic and gum tragacanth gives a good cement which will keep for a long time. Impervious. An impervious cement for apparatus, corks, &c., may be made by rubbing up zino white with copal varnish ; this is applied and left to dry, then covered with the same material mixed thinner, and lastly with copal varnish alone. Indianite. (a) Finely-chopped indiarubber, 100 parts; rosin, 15 parts; shellac, 10 parts; dis- solved in a sufficient quantity of bisulphide of carbon ; (6) indiarubber, 15 grs. ; chloroform, 2 oz. ; mastic, oz. ; the first and second ingredients are mixed, and, when the rubber is dissolved, the mastic is added in powder, and the whole is left to macerate for a week. These cements are used for uniting pieces of indiarubber. Indiarubber. (a) Virgin or native indiarubber is cut with a wet knife into the thinnest possible slices, which are then divided by shears into threads as fine as small twine. A small quantity of the shreds (say -fa of the capacity of the bottle) are then put into a wide-mouthed bottle, and the latter is three-fourths filled with benzine of good quality, and perfectly free from oil. The rubber almost immediately commences to swell, and in a few days, if often shaken, it will assume the con- sistence of honey. Should it be inclined to remain in undissolved lumps, more benzine must be added ; thinness may be corrected by adding more iudiarubber. A piece of solid rubber no larger than a walnut will make a pint of the cement. It dries in a few minutes, and, by using three coats in the usual manner, leather straps, patches, rubber soles, backs of books, &c., may be joined with great firmness. (6) Indiarubber, 3 grms ; chloroform, 600 grms. ; mastic resin, 150 grms. ; the india- rubber is dissolved in the chloroform, the mastic is added, and the whole is left to macerate for eight days, that being the time necessary for the solution of the mastic. The cement is applied cold on a brush, and is used for joining glass, (c) Very finely-divided indiarubber is melted at a temperature of 200 (392 F.) ; as soon as fusion commences, one-fifteenth the quantity of tallow or wax is added, taking care to watch the heat and to stir without ceasing. When the mass is com- pletely melted, lime, slaked and sifted, is added in email instalments, till it amounts to half the quantity of the indiarubber. The cement thus obtained is soft ; if the proportion of lime be doubled, the cement will be harder, but still supple. When the compound has acquired a suitable con- sistence, the fire ia withdrawn, and the preparation is finished. This forms a good cement for hermetically sealing vessels. It does not dry, and remains for a long time ductile and tenacious ; but it may be made to harden, if necessary, by adding 1 part of red-lead to the quantities indicated above. Ivory, or Mother-of-Pearl, for. Isinglass, 1 part, and white glue, 2 parts ; dissolved in water, 30 parts ; the solution is filtered, and evaporated down to 6 parts ; to this i added gum mastic, gij part, dissolved in alcohol, part ; and zinc white, 1 part When required for use, it is warmed and shaken up. Jewellers'. (a) Gum mastic, five or six pieces as large as peas, is dissolved in as much spirits of wine as will suffice to render it liquid ; in a separate vessel, is dissolved, in rum or other spirit, as much isinglass, previously softened in water and strained dry, as will fill a 2-oz. phial with very strong glue, adding a little gum galbanum or ammoniacum, which must be rubbed or ground till it is dissolved. The whole is then mixed, under the influence of sufficient heat. It is kept in a closely stoppered bottle, which is placed in hot water when the cement is to be withdrawn for use. It will effectually unite most substances, even glass to polished steel, and is principally used for joining broken pieces of china and glass. (6) The following is another mode of preparing the same ingredients : Isinglass, 1 oz., in distilled water, 6 oz., boiled down together to 3 oz. ; to this is added strong spirits of wine, I \ oz. ; the mixture is boiled for a minute or two, and strained ; while still hot, it receives, first, milky emulsion of gum ammoniacum, oz. ; then, alcoholic solution of resin mastic, 5 drachms, (c) Shellac, melted and run into sticks as large as quills. Used for joining glass, earthenware, &c. ; the edges are heated sufficiently to melt the cement, which is then applied, and the joint is made while the heat lasts. (<*) Tears of gum mastic employed in the same way. (e) Shellac, 2 parts, Venice turpentine, 1 part ; fused together and formed into sticks. Used as the preceding. Labels, for. Gelatine, 25 grammes ; sugar-candy, 50 grammes ; gum arabic, 12 grammes ; water, 100 grammes. After having macerated the gelatine in water, overnight, it is mixed with the sugar and gum arabic in a porcelain vessel, and heated over a spirit lamp, with constant agitation. Ebullition must be continued till the mass becomes quite fluid. The labels are coated with the liquid, and left to dry ; on moistening the coated surface, they will adhere strongly to glass and wood. Lapidaries'. (a) Rosin, 1 Ib., is melted, and to it is added dry plaster of Paris, 4 oz. Makes a very strong cement for rough purposes. (6) Rosin, tempered with beeswax and a little tallow, and hardened with whiting and red ochre, or Spanish brown. CEMENTS. 625 Leather, for. (a) Guttapercha dissolved in bisulphide of carbon, to form a mass of treacly con- sistence. This forms a good cement for splicing leather. The parts to be joined must be thinned clown ; a small quantity of the cement is then poured on each end, and spread so as to thoroughly till all the pores of the leather ; the parts are warmed over a fire for a few moments, applied quickly, and hammered well together. To preserve this cement, it should be tightly corked in a bottle, and kept in a cool place. (6) Guttapercha, 1 Ib. ; indiarubber, 4 oz. ; pitch, 2 oz. ; shellac, 1 oz. ; linseed oil, 2 oz. ; melted together. It hardens by keeping, and needs remelting before application. Leather and Metal, for. A cement for joining leather and metal may be made by melting together equal parts of asphalt and guttapercha, and applying the mass hot under a press. Marble, for. The following curious composition is recommended for cementing pieces of marble, porcelain, or glass. About 100 snails are caught, and kept fasting for two months or less, taking care to clean them occasionally. They are then sprinkled with a little water to make them quit their shells, the excess of water being decanted as soon as they have come out. Thereupon is added a pinch of culinary salt, then the juice of four or five lemons, and a drop of vinegar, and the whole is beaten up together. The snails give off their mucus, which is collected, and intimately mixed, in a mortar, with 8 grammes of gum tragacanth, then 40 or 50 grammes of garlic juice, and 200 grammes of alcohol. The cement keeps quite opaque, and may be coloured to suit the materials to be joined. It is applied cold ; but the joint must subsequently be exposed to the sun or a fire. " Marine Glue." (a) Finely shredded indiarubber, 1 part ; coal-tar (or mineral) naphtha, 12 parts ; digested in a covered vessel with heat and agitation ; when the solution is complete, 20 parts of powdered shellac are added ; the heating and stirring is continued till perfect lique- faction has taken place ; the fused mass, while still hot, is poured out on slabs of polished metal or stone, so as to form thin sheets. For use, it is heated to its melting-point, 120 to 121 (248 to 250 F.), in an iron vessel, and applied, in a liquid state, with a brush. It is used by shipbuilders and others. (6) Indiarubber, 15 to 20 grains ; chloroform, 2 fl. oz. ; dissolved ; powdered mastic, J oz., is added. The cement must be kept well corked, and in a cool place, to prevent loss by evaporation, (c) Finely divided indiarubber, 1 part, is dissolved in naphtha oil, or crude naphtha, 40 parts. The solution is not completed in less than ten or twelve days, and, in order to facilitate it, the mixture should be repeatedly agitated. To it, is then added gum lac, in the proportion of 2 parts by weight of lac to 1 part of solution. The compound is then placed in an iron vessel over a fire, and constantly thinned till it becomes homogeneous. It is then poured on a cold surface, such as a slab of marble or a n'ag-stone, and left till cool, when it is broken up and put by for use. The indiarubber is sometimes omitted, in which case, the proportions will be 1 part of naphtha and 2 parts of lac. When required for use, the cement is heated at a temperature not exceeding 100 to 110 (212 to 230 F.), in a thick vessel of copper or cast iron, and is brushed in thin and even layers on the surface to be joined ; these are then brought into close contact, and strongly pressed. If the surfaces are so wide that the cement becomes cool before the operation is finished, it is well to pass a hot iron say at about 60 (140 F.) over it. It is valuable, not only for repairing broken wood, but also for cementing the moulds used in foundries, for caulking ships, for joining blocks of marble or granite, and for uniting wood and iron. It can be made aa hard as desired, by increasing the proportion of lac. With the addition of bichloride of mercury dissolved in wood spirit, this cement might, with economy, replace the copper sheathing of ships. Wood, iron, plaster, and brick, to which it is applied, assume a varnished appearance ; timber /a rendered free from the attacks of insects and from liability to rot, and iron is preserved from rust. Metal or Glass, and Wood, to join. (a) Eosin is melted, and into it is stirred calcined plaster till the mass is reduced to a paste, to which is added boiled oil, in sufficient quantity to bring it to the consistence of honey. It is applied warm. (6) Into melted rosin, 180 parts, are stirred burnt umber, 30 parts ; calcined plaster, 15 parts ; boiled oil, 8 parts. Metals and Glass, to join. (a) Rosin, 4 to 5 parts ; wax, 1 part ; colcothar, 1 part ; the whole melted together. A little powdered plaster is often added. (6) Copal varnish, 15 parts ; drying oil, 5 parts ; turpentine, 3 parts ; essence of turpentine, 2 parts ; strong glue, 5 parts ; slaked lime, 10 parts ; mixed, (c) Sandrach or galipot varnish, 15 parts ; boiled linseed oil, 5 parts ; turpentine, 2 parts; essence turpentine, 2 parts; marine glue, 5 parts; pearl white, 5 parts ; dry carbonate of lead, 5 "parts; mixed. (e gas itself is submitted, after leaving the hydraulic main, has more to do with enriching the tar than all the other conditions combined. The specific gravity of tar ranges from '95 to 1 -25 ; that of samples containing much naphthalene will fluctuate between 1-10 and 1-25 : and such tars, being heavier than the " ammonia liquor," will sink in the tanks ; the density of tars obtained from Scotch cannel coal approximates that of water, being sometimes a little above it, at others a little below in such tars the naphthalene is replaced by paraffin. London tar is always heavier than country tar ; high heat increases the quantity of naphthalene. The larger gas companies generally dispose of their tar by contract ; and, though there are most important differences in the quality and quantity of the distillate from tars of various origin, and produced under varying conditions of temperature, the distiller is unable to exercise any control over the character of the tar supplied to him. The tar is freed from the ammonia liquor, as far as is practicable, by allowing it to settle. It is then removed from the gasworks, in tanks fitted to railway trucks, or waggons, or in iron barges. On arrival at the works, the tar is pumped into large tanks of masonry or iron, sunk into the ground. Here it is left to settle for some days, to enable the watery portion to separate out. When the tar is very thick, the separation of the watery portion is facilitated by means of heat ; through coils of copper or iron pipe placed in the tanks, steam or hot water is passed, until the tar is rendered fairly fluid. Over-heating should be avoided, as it might drive off the more valuable constituents of the tar. Too much care cannot be taken to free the tar from water, especially if the tar happen to be very thick, as is always the case in cold weather. The presence of water causes the tar to froth when being distilled, so that it boils over through the worms ; it may even lift the still head, when contact with the fires will produce disastrous results. Tars which approximate the sp. gr. of water are not easily dehydrated ; their distillation is best conducted on the Scotch or French systems. The inflammability of the tar pro- ducts necessitates every precaution against fire. The tanks in which the liquids are collected are placed as far as possible from the furnaces, and are kept securely covered. As fires occur most frequently at the stills, it is best to isolate them from the general plant altogether ; and, since it is impossible to extinguish burning tar, it is a good plan to supply each still with an outlet, at or near the bottom, communicating with an empty boiler or still, so as to run off the tar from the burning matter as quickly as possible. By taking this precaution, the opening of the outlet relieves the pressure due to frothing, and renders an accident from this cause much less liable to occur. There are three methods of treating tar English, Scotch, and French ; it will be necessary only to give those points of difference which render one method better suited than another ia particular cases. To avoid confusion, it may be well to point out that the treatment of tars varies according to their qualities and sources; unless otherwise stated, the remarks in this article apply to English tars, ordinarily obtained from London and country gasworks. London tar weighs 11 to 12 J Ib. a gall. ; country tar, about 10 Ib. The tars known as " Midlands " are the most sought after by distillers; having been distilled at a lower temperature than the London tars, they are richer in benzol. When the heating is very low, the benzol may be replaced by eupion. London tar is principally obtained from Newcastle cannel or bituminous coals. Scotch cannel yields 15J gall, of tar and 32 gall, liquor a ton ; caking coal yields about half as much. The nature of the tar from the same coal will vary according to whether the retorts used are of clay or of iron ; clay retorts are more strongly heated, which circumstance is said to diminish the benzol and increase the naphtha- lene. This may explain why country tars are preferred to London tar. The form and capacity of still used in the " fractionizing," or fractional distillation, of coal-tar vary, principally, according to the extent of the works. The smallest capacity considered economical ia 500 gall. ; in large factories, stills holding from 1200 to 2500 gall., and even 4000 to 7000 gall, are used. A great advantage with the larger size is that it enables a manufacturer to dispense with much stowage space in the form of tanks, and consequently saves a great deal of *abour ; on the other hand, an accident is of much more serious consequence, and the charge cannot 2 T 642 COAL-TAK PEODUCTS. be run over without involving nightwork. For small works, those stills are preferred which admit of working off a charge in ten or twelve hours. The largest.stills are convenient for dealing with special descriptions -of tar, and in special modes of distilling. The most convenient size is 2500 gall., which, on the English system, is run over in about thirty-six hours. In arranging the plant for a tar distillery, the great object is to enable the tar to oe worked up as rapidly as possible, and with the smallest amount of labour. lu the winter months, increased supplies frequently involve the erection of a few extra stills. The varying consistence of the tar may necessitate modifications in the method of distilling, so that it is almost impossible to prescribe any general rules in erecting the plant for this business. A few extra stills should always be put up ready for use. There is no doubt that eventually most large gas companies will utilize then- own tar ; in such cases, it would be easy to determine what plant should be erected, because, as a rule, the coal used is the same, and the conditions of heating are likely to be kept uniform. The manufacturer who purchases his tar from several gasworks has to put up with a variable product. The English stills are constructed of -in. boiler plates riveted together ; the portions whici: are likely to be more strongly heated are made thicker. If the distillation is to be carried to coking, cast iron should be used, as it does not burn out so rapidly, and needs no joints. To prevent burning, the bottom of the still rests upon, brickwork, except in the coking process. The form of still chiefly used hi England is that shown in Fig. 481. The "head " consists of a bent cast-iron pipe a, communicating with a series of iron pipes 6 arranged in a tank as a condenser. At the top of the still is a manhole c, and an inlet d for the tar; in some cases, the same inlet is used for injecting super- heated steam, either for distilling purposes, or for driving out the pitch after the charge is finished. Around the neck of the still is a channel for collecting the portions which condense in the head ; these are added to the distillates, as their falling back into the still may cause frothing, which is dan- gerous. Near the bottom of the still is a pipe for removing the residue. The stills are heated by separate furnaces, and are arranged under a light shed, so as to protect the workmen from the weather. They are sometimes enclosed in brickwork, as shown, with the view of preventing loss of heat. The heating flues should not reach above the space occupied by the contents of the still at the end of the operation. For a tar which is rich hi light hydrocarbons, such as that yielded by Scotch cannel coal, and by the better kinds of lignite, another kind of still is required, as the application of fire-heat would be accompanied by danger. The method adopted with these tars is to distil them by steam-heat, in order to remove their more volatile constituents, until the residue in the retorts is reduced to a thick mass, known as " boiled tar." This is then withdrawn into tanks, or is pumped into other stills, in which the distillation is carried on in the usual way. These tars, being richer in benzol and anthracene oils, are much sought after by distillers, though the separation of water from them is more troublesome. The process, which is known as the " Scotch method," is conducted in the following manner : The " green," or raw, tar is pumped from the settling tanks into stills S, Fig. 482 having a capacity of 4000 to 5000 or more gallons, and made of f-in. boiler plate. A perforated steam-coil lies at the bottom of the still, or steam is admitted through branches p, with valves V, from an inlet pipe I. The stills should not be more than f filled, say to W, as plenty of room must be allowed. The distillation is carried on until the distillate acquires a sp. gr. of 0'930; the residue in the retort, known as " boiled tar," is then run out, through a hole near the bottom, into tanks, or is pumped into other stills at once, for further distillation over a naked fire. This process commends itself for several reasons ; the most important are that the rapid recovery of the volatile constituents of the tar allows a large quantity to be worked up expeditiously, and that the naphtha obtained is more free from smell, and will keep better on exposure to the light. When the lighter portions are drawn over, the residue is stowed away for working up in slack time. Much of the so-called 482. 1 TAR DISTILLATION. 643 Scotch "solvent naphtha," now met with in commerce, behaves under acids so differently from English naphthas that it is questionable how far it can be used as a substitute for them. A great merit of the best Scotch naphthas is the absence of naphthalene from the "solvent" fraction. The crude or " once run" naphtha obtained by this process is again distilled with steam, and the products are collected at different temperatures, as required. A residue, amounting to about 7 per cent, of the " once run " naphtha, is left in the still ; it has a thick, tarry consistence, and is run in with the creosote oils, or sold to rosin-grease makers at 50s.-65s. a ton. In distilling with steam, a large quantity of water passes over with the product ; as this continues during the whole opera- tion, the distillate is received in a " separatory " apparatus, so as to allow the water to escape. This consists of a magnified " Florentine receiver," in the form of a rectangular iron tank. The "boiled tar" is distilled in vertical or horizontal stills, heated directly by a furnace. The heating should be very gradual, as this tar contains considerable quantities of water. About 1000 gall, yield 200 gall, of rough naphtha, which should give about 120 gall, of naphtha suitable for burning, &c, and about 320 gall, of creosote oils. The residual pitch will amount to 35-55 per cent., according to the temperatures at which the distillation has been conducted. Ernest Smith says that in distilling Scotch cannel tar by the Scotch system, a little light oil, sp. gr. 0'850, first passes over, after which a rise takes place, and the whole of the light naphtha marks 890. The sp. gr. of the second naphtha is 910 ; to collect this, the receivers are changed, when the distillate rises to - 930. The crude light naphtha from the best tars yields 10 per cent. at 120 (248 F.), with a sp. gr. of 0*880. He states that paraffin appears more copiously in tara obtained from cannel coal at a low heat, and that generally the anthracene, before purification, contains a larger quantity of paraffin. This certainly will help to account for the great differences in Scotch solvent, and explains the discordant figures given by various authors. A continuous process of distilling has been lately introduced : by running the tar over molten lead the more volatile part is driven off, and the residue is received in retorts for further treatment. The " French system " of distillation differs mainly in drawing off the aqueous portion of the tar at a much lower temperature. It is frequently effected in jacketed stills, or by means of circulating steam pipes. The same method is obviously applicable for drawing over the lighter oils, or for carrying on the distillation so as to separate the constituents of the tar at one operation. " Liquid pitch," or " thick tar," contains a little of what corresponds to the second light oils of the English method, and all the heavy oils ; " fat pitch " is deprived of all the light oils, and partially of the heavy oils; "dry pitch" is obtained by heating until liquids are given off. The condenser usually employed consists of a series of 4-in. flanged iron pipes, joined together by cast-iron elbow-pieces, and arranged in a water-tank in zigzags or ovals. The joints are best made with sheet lead ; where cemented joints are required, slaked lime worked up with a little tar makes a lute, which, after hardening, stands for a long time. For convenience in cleaning the condensing tubes, they are joined by tee-pieces, and the ends which project through the tank are closed by iron plugs or caps. The length of worm required is a matter of some importance : the liquids which come over at the first stage of the operation should be well cooled, whilst the heavier oils, if cooled too much, would choke up the tubes. The cooling must be so regulated that the distillate shall flow freely away to the receivers. About 160 sq. ft. of condensing surface is sufficient for a still working off 2000 gall, of ordinary tar per twenty-four hours. If the product solidify on cooling, or if much naphthalene come over with the creosote oils, it may be necessary to stop the cooling altogether, or even to heat the water in the worm-tank by injecting steam. It is not easy to define precise regulations, and, in operating upon a new sample of tar, it is by far the best plan to watch the distillate itself ; for not only is it a matter of great importance to know how to adjust the condenser, but the proper time for changing the receivers must be ascertained, especially if the preliminary distillation is used for partial fractionizing. In treating ordinary English tar, the distillation is thus conducted : The firing is generally got up as the filling progresses. It is important to raise the heat very cautiously, and to watch for the commencement of the distillate going over ; this can be done by feeling the condensing tube, and, as soon as it becomes warm, the fire should be checked, the object being to distil very gradually at first, and to make tolerably certain that all the watery portion has come over. If frothing occur, the still head may be cooled with water, unless the still be of cast iron. The water present in the tar makes the distillate come over more copiously. The first distillata consists of water charged with ammonia ("ammoniacal liquor"), and the more volatile hydrocarbons. As soon as the water has stopped, the receiver is changed, and the heating is slightly increased. The product which now passes over is called " first light oils," and amounts to 8-10 per cent, of the quantity of tar originally taken. During this time, the temperature gradually rises, from the fact that the tar parts from its more volatile portion, and what remains has a much higher boiling-point. In the earlier part of the process, the refrigeration must be as perfect as possible ; but as the receivers are changed for the heavier and less volatile portions of the distillate, it is not so essential to keep 2 T 2 644 GOAL-TAB PEODUCTS. them very cool. This is not entirely a matter of economy of water: a little heat facilitates the flow of the condensed liquids, and hastens the distillation. In the English and Scotch systems, the receivers are changed for collecting what is known as " second light oils," and there is no doubt as to the advantage of this, especially where large quantities of tar are treated ; by the French method, no fraction is obtained corresponding to this. The distillation is carried on until a few drops of the distillate will sink in water ; but it is better to stop the collection of second light oils. at an earlier stage, for the distillation of some tars, as those yielding paraffin, can be carried on at a very high temperature without yielding a product heavier than water. It is better to use a thermometer, and to change the receiver as soon as the temperature is sufficiently high. With ordinary English tar, the first, and second light oils are collected until the distillate sinks in water, when the receivers are Changed for the " heavy oils," " creosote oils," or " creosote." As the product now contains much naphthalene, which may choke the condenser, the latter must be kept warm ; diminishing the flow of cold water will secure this under ordinary circumstances, but it may be necessary to heat the condensing worm, if large quantities of naphthalene are present. After a time, the distillate changes again, and has a green colour ; this is known as "anthracene," or "green oils," and is collected in a separate receiver. Towards the end, the distillate becomes black, and the receivers are finally changed for what are termed " last runnings." The residue contained in the retort constitutes pitch, which, while still liquid, is drawn off (or blown out by superheated steam) into a closed tank, to cool down to about 204 (400 F.), before being placed in its ultimate receptacles. The reason for this is that its temperature is so high that it would readily ignite, if immediately exposed to the air. Neglecting the ammonia, which has been already treated of at p. 232, the products of the fractional distillation of coal-tar are : 1. " First light oils," with water and ammonia, passing over at . . . . 100 (212 F.). 2. "Second light oils," or "once ran "(or crude) naphtha, passing over at 149 (300 F.). 3. " Heavy oils," or " creosote oils," or " creosote " 171 (340 F.). 4. " Green oils," or " anthracene " 204 (400 F.). 5. " Black oils " 425 (800 F.). 6. Pitch, left as a residue. The temperatures given are approximately those at which the receivers are changed. On the French system, the fractions are collected at slightly different temperatures. The next consideration will be the products derived from each of the above-mentioned groups, omitting all theoretical or purely scientific elements, as well as compounds of no immediate importance. Once-run (or Crude) Naphtha. This liquid is almost colourless when freshly drawn over, but rapidly acquires a brownish tinge, by oxidation, on exposure to the air and light. It ia rather curious that those constituents of coal-tar which are so readily affected by light appear to have escaped the attention of the scientific photographer. A test for the purity of rectified naphtha is its non-changeability in colour on exposure to light ; and the treatment to which it is subjected is for the purpose of removing those principles which render it liable so to change. If the receiver has been changed after the water has passed over, the crude naphtha will be con- siderably less rich in those principles which boil at or under 100 (212 F.), and the watery vapour will have carried over much of those having a boiling-point above that of water. This is more perceptible with those tars which are lighter than water, for the vapour, in passing through the tar, mechanically carries over a little of all the principles contained in it, and which of themselves would not go over except at a higher temperature. If the receiver has not been changed, the crude naphtha will contain the first and second light oils. In the case of tars containing much creosote, it is more economical and convenient to split the crude naphtha into first and second light oils at the first operation. Many manufacturers of benzol, solvent naphtha, and aniline products, purchase crude naphtha from the tar distillers; and as this product varies in composition and value, the manufacturer should know what he ia actually purchasing. Its value chiefly depends upon how much it contains of benzol toluol, xylol, and cymol, which come over at different temperatures, and upon their sp. gr. It is submitted to a rectification or second distillation, with or without the oily portion which separates out of the ammoniacal liquor. The latter is best treated separately, as it consists mostly of benzol and toluol, and is consequently a convenient source of high-class benzols. The object of the eecond distillation ia to separate the more volatile benzol and toluol, and to clear the solvent naphtha of a great portion of the heavy oils. It is pumped into a still, heated by steam or hot water, and covered with felt and cement, to prevent the heat escaping and raising the temperature of the room The process is governed by the temperature indicated by a thermometer Immersed in the vapour. This operation is carried on with extra care ; the vapours arc le'l away to an efficient condenser at some distance from the building, and the liquor Is NAPHTHA. 645 received in covered tanks sunk in the ground. As a rule, the crude naphtha is only fractionized once ; but it may be split up into different products, according to the requirements of the manu- facturer. To produce high-class benzol, the receivers may be changed as soon as the temperature rises to 100-104 (212-220 F.). The usual plan is to allow the distillate to flow into a closed vessel supplied with two or more cocks, and containing either a hydrometer or some excisemen's beads, so as to guide the distiller in changing the receivers. Scarcely two distillers fractionize naphtha in exactly the same way ; everything depends upon what it is wished to extract, without rendering the residue unsaleable. Some collect the distillate until the temp, rises to 115-121 (240-250 F.) ; others go so far as 132-138 (270-280 F.); and others, again, make only one change of the receivers, collecting, at 121-132 (250-270 F.), all that comes over until the temp, rises to 149-160 (300-320 F.). The capacity of the stills must depend on the number and extent of the fractionizings. A disadvantage is experienced from splitting the distillates into too many products ; but this is removed by collecting the products of the first distillation, in such a way that two fractionizings will be sufficient for the second distillation of each of the first products. In the rectification of the crude naphtha, whatever comes over at the lowest temperature should be added to the second product obtained in the first distillation, and thus the products should be treated throughout. To avoid repetition, it may be stated here that the treatments of all the products are pretty much the same. Dilute acids are used to separate the bases, and alkaline solutions are employed to remove the acids, the process being called " washing." In particular cases, steaming is used to facilitate it, when special appliances are necessary to avoid evaporation. The following synoptical arrangement will give a clear idea of the primary products obtained by ordinary fractionizing on the English system : B'. IST, OR PRELIMINABY DISTILLATION. Stills charged with gas-tar, yield : A. 1st Product, containing : 1st Light Oils. Water charged with ammonia, &c. Benzol \ going over with the \ .. Toluol, &c. J vapour of water. / ' B. 2nd Product, containing : 2nd Light Oils. Toluol } small quantities. Xylol i principal Cymol j constituents Heavy oils, &c., small quantities. C. 3rd Product, containing : Creosote, or Heavy Oils. Carbolic acid j Cresylic acid [ C'. Naphthalene, &c. j D. 4th Product, containing : Green Oils. Anthracene, &c. D'. E. 5th Product, containing : Dead oil, or Last runnings F. 6th Product. >E'. Pitch. 2ND. DISTILLATION OB RECTIFICATION. Stills charged with products from gas-tar, yield: A'. Obtained from A by standing to sepa- rate. Ammonia liquor. Benzol. Residue added to B. B'. Obtained from B. Benzol, 40 per cent, to 60 per cent. Toluol. Solvent naphtha, with small quantities of light and heavy oils. Residue added to C. C'. Obtained from C. Crude creosote : Separated by pressure, &c., into Carbolic acid. Cresylic acid. Naphthalene. D'. Obtained from D by heat and pressure. Crude anthracene. Residues added to crude creosote, or re- distilled. E'. Obtained from E and F. Soft pitch contains the dead oils. Hard pitch is deprived of a great deal of these oils. When the tar is distilled so as to yield a hard pitch, by removing as much as possible of the anthracene oils, it is converted into softer kinds by addition of the creosote oils. This list gives only the principal constituents of each product ; by repeated fractionizings, their proximate constituents may be isolated, according to the purity required for the commercial article. The tar distiller rarely has to carry his operations so far as to obtain more than the approximate separation of the series contained in the second column. As the preliminary treat- ment of most of these is almost identical, it will suffice to give one general description. Washing. Formerly, the crude naphtha and light oils, freed from their watery portions, were pumped into large, lead-lined, wooden vats, and agitated by perforated rotating fans, for some hours, with sulphuric acid and caustic soda solutions, each washing being followed by a good agitation with water. The acid and other liquids must enter in a 'fine spray. Now, it is the general practice to re-run the crude; naphtha before washing, as many impurities are thus removed, and a saving of 646 COAL-TAR PRODUCTS. material is effecte.l. Sulphuric is preferable to other acids, because it more easily carbonizes the impurities, and causes them to separate out as a soft resinous mass, in addition to which, it forms, with the bases, salts which can be removed by washing. About 3 per cent, by measure of acid (c. o. v.) is gradually diffused through the liquids, and the whole is well agitated ; on standing, the impurities collect on the bottom ; the naphtha is drawn off into another tank, to be agitated for five or six hours with 6 per cent, of acid. After settling, it is again drawn off, and agitated with repeated fresh supplies of water, until all the acid is removed. The water is drawn off, and the naphtha is then agitated with 10 per cent, of a solution of caustic soda, sp. gr. 1 03. Some- times milk of lime is added ; but its use requires extra care. After standing for some time, the naphtha is treated with water as before, or is pumped into a still, and drawn over by superheated steam. Three washings with acid are given, the last being sometimes with a mixture of sulphuric and weak nitric. The acid sludge has been largely used for making superphosphate. After the separation of the water by standing, the naphtha should be colourless, i. e. " water white," and remain nearly so on exposure to light ; this is the best test of thorough washing. For " second light oils," caustic solutions are first used, as the chief matters to be removed are carbolic and other acids. As these vary in different naphthas, a preliminary test is made, to ascertain how much caustic solution is required (see Carbolic Acid, p. 44). After removing the soda-salt formed, by washing with water, the whole is left to settle ; the liquid is drawn off and treated with acids, as above, or is first submitted to distillation. Various ways of carrying out these rectifications are adopted by different manufacturers ; some have only ideal advantages, whilst others are more useful. As a rule, it is found that by pushing the distillation too far, in the preliminary treatment of the tar, little or nothing is gained. The object is to minimize the washing, which means saving acid and alkali, as well as labour. A saving of acid and alkali is effected by not allowing the heavy oils to go over with the second light oils, and, for the production of solvent naphtha, this is an important consideration. It is necessary to guard against loss from evaporization, caused by the heat generated on mixing the naphtha with acid or alkali. The products, either crude or rectified, are redistilled for new products. The stills used for fractionizing the crude naphtha are known as Coupler's and Clark's. The rapours are condensed in a leaden worm, and the liquids are received in a closed box with glass sides, containing some coloured " specific gravity beads " ; at the bottom, are several cocks communicating with separate tanks for the reception of the fractionized products. The still is covered with felt and cement. It converts the crude products into second-class benzols, toluols, and solvent naphtha, tlie residues being drawn off into the creosote tanks. The condensation must be thorough, to prevent escape of the vapour, which, from these portions of the distillate, is very inflammable. In the first fractionizing by Coupler's still, the proximate principles are only comparatively isolated, though more so than is usual with the English products ; but by submitting the products to a second or third rectification, it is possible to separate the principles very completely. Thus Coupler's distillates have justly earned an enviable reputation. His still is used principally on the Continent. Clark's still, like the one previously mentioned, is, in many respects, similar to the Coffey still (see Ammonia). It may be used in a variety of ways ; the same results may be attained as by Coupler's still, but with the advantage that the liquid is broken up into several products at one operation. Few manufacturers adopt these methods, unless for some special purpose. The most economical way of working is to take advantage of the preliminary distillation for the first fractionizings, and, in re-running the crude naphtha, to follow a similar plan. This entails a greater outlay in tanks for stowage, which may be economically replaced by puncheons, provided they can be kept from leaking, and from allowing the lighter products to penetrate the wood. Solvent naphtha, or, as it is more frequently called, " solvent," is much used in the manufacture of indiarubber waterproof goods, as it readily dissolves or softens indiarubbor. It is also a solvent of resins, oils, &c., and, at one time, was largely used in the manufacture of varnishes, paints, and cements ; but for such purposes it is now almost entirely replaced by the lighter kinds of petroleum. It is often adulterated with petroleum or shale oils. Good solvent naphtha, from English tar, has a sp. gr. of about 0'870 at 15 (60 F.), and should commence to boil at about 118 (245 F.), although it frequently requires 121 to 127 (250 to 260 F.) before any appreciable distillate goes over. Between its boiling-point and 142 (288 F.), about 70 or 80 per cent, of its bulk should pass into the receiver, and the sp. gr. of this fraction should be a trifle less than that of the original sample. The distillate collected between 142 and 160 (288 and 320 F.) should be a little heavier than the sample, and should correspond to 15 or 20 per cent, of the original bulk. The residues, when containing naphthalene, are often as high as sp. gr. 0'950, and solidify in cold weather ; otherwise the sp. gr. of the residues and fractions will not vary much from that of the solvent itself. When petroleum or shale oils are present, either as adulterants, or when the naphtha is derived from the tar of cannel coals, the sp. gr. will be 0'845. Scotch solvent goes over at lower temperatures than the English product, and is of lighter sp. gr. If much distil at or below BENZOL. 647 118 (245 F.), petroleum oils are probably present ; this can be ascertained by the sp. gr. of the fractionized product. Scotch solvent gives 95 per cent, distillate at 160 (320 F.). The vapours of solvent naphtha have a peculiar intoxicating power over those unaccustomed to its use; a person thus affected rapidly recovers when taken into the open air. The effect is indicated by giddiness and hilarity, which is not followed by depression on recovery. It is rare for the same individual to suffer more than one or two attacks. The ventilation of the buildings where it is evaporated is generally well arranged. Formerly, they were lighted, when necessary, by gas jets fixed outside the windows; now, a good supply of air is admitted, and dilutes the vapour so rapidly as to remove all chance of explosion. (See Indiarubber Manufactures.) Benzol, or Benzene. C 6 H 6 . This liquid was discovered by Faraday in 1825, and was named by him "bicarburet of hydrogen." In 1834, Mitscherlich obtained it by distilling benzoic acid with hydrate of lime. It may also be procured by passing benzoic acid through a red- hot tube. A mixture of one part of benzoic acid and three parts of slaked lime yields, by distilla- tion, benzol in a pure state, and calcic carbonate. The mixture should be gently and gradually heated ; the benzol, which goes over with a little water, is separated from the latter, and distilled over a solution of caustic potash. Benzol is one of the most important principles of gas-tar ; it exists largely in the petroleums known as Eangoon tars, and in some of the petroleums of Europe, the Caspian, &c. When pure, it is a colourless mobile fluid, boiling at 81 (178 F.), and solidifying at 3 (37 F.) into a colourless crystalline mass. Its sp. gr. at (32 F.) is 0'899, and at 20 (68 F.), 878. It has a peculiar aromatic smell, is very inflammable, and burns with a smoky flame. It is slightly soluble in water ; but dissolves freely in alcohol, ether, carbon bisulphide, and the liquids obtained by distillation from gas-tar. It is also miscible with the petroleums. It dissolves iodine, sulphur, phosphorus, fats, oils, resins, guttapercha, and indiarubber. It may be used in varnishes and in paints, as a substitute for turpentine ; but its price is too high for this at present. It removes grease spots from cloth, silk, &c. Its volatility renders it a convenient source of illumination. The " Benzol " or " atmospheric" light is obtained by passing a current of air or hydrogen through benzol. The saturated air is distributed in the same way as coal-gas, and burns freely. The conditions which operate against this method of illuminating are condensation in cold weather, and the difficulty of saturating the air at low temperatures. The fact that benzol solidifies when cooled to a low temperature supplies a method for its puri- fication on a large scale. The solidified mass is submitted to pressure, by which the benzol is freed from its liquid impurities ; by redistillation alone, this would be almost impossible. Benzols which become solid at 1 (30 F.), are prepared for special purposes. In commerce, it is rarely met with in such a state of purity ; but is sold as 90 per cent., 40 per cent., &c., which means that when the sample is distilled, 90 per cent., 40 per cent., &c., passes over at or below 100 (212 F.) : 90 per cent, is the highest commercial rectification, and in preparing pure benzol it is better to work upon this basis. Pure benzol is obtained from the commercial article by repeating the process for the production of the latter, and expressing the congealed mass. It is of great importance when purchasing benzol, toluol, naphtha, &c., first to have an under- standing with the seller, as to the conditions of performing the distillation : 1. The quantity to be placed in the retort for distilling. 2. The capacity of the retort. 3. Whether the bulb of the thermometer is to be immersed in the liquid or in the vapour. 4. The rate, whether in drops or in a stream, at which the distillate shall pass over. 5. The method of applying the heat. 6. When the distillation shall be considered complete. Corrections for barometric pressure may sometimes be necessary, and, in all cases, the distillate should be measured at the same temperature as the liquid, the loss due to imperfect refrigeration and condensation being considered as a part of the distillate. The residue, if measured off immediately the distillation is ended, will be warm ; if left in the retort to cool, the few drops collected in the receiver after the distillation is ended must be regarded as part of the residue. This may easily give rise to a difference of 2 or 3 per cent. Manufacture and Rectificativn. Several forms of apparatus for separating benzol from once-run naphtha have been already mentioned. The essential feature in all of them consists in receiving the vapours in a condenser kept at such a temperature that only those liquids can pass over which are vaporizable at that degree, those vapours which are condensed at this same degree being returned to the still. By using a series of condensers, the liquid may be fractionized to any extent at one operation. This portion of the factory is kept cool, and is placed as far as possible from boilers and furnaces, on account of the volatility of benzol and the inflammability of its vapour. The distillation is effected by steam or heated water, as it is then easier to regulate the temperature ; direct heat colours a portion of the liquid. The vapours are collected in another boiler, placed on end, provided with a thermometer, and jacketed so that it can be kept at any required temperature by steam 648 COAL-TAR PRODUCTS. or water; those vapours which are condensable at that temperature are here arrested, whilst tlie others pass on to a properly cooled receiver, whence they are delivered into a vessel provided with two or more taps, communicating with stowage tanks. When the temperature of the intermediate condenser is so high as to keep the benzol in a state of vapour, the product will be richer. When it is desired to collect the distillate at different temperatures, the jacketed boiler is heated to, say, 82 (180 F.), so as to allow the benzol to pass over ; as the temperature is raised, the cock leading to the benzol tank is closed, and another cock is opened, so as to collect the second distillate : thus any number of products may be drawn over from the same still of crude naphtha. The crude benzol is washed by thorough agitation with strong sulphuric acid in well-closed, lead-lined vats ; on the large scale, the agitation is performed by steam power ; the acid is then drawn off, and the benzol is well washed with water. These operations are repeated according to the degree of purity required, or until the acid drawn off is nearly colourless ; the final washing ia with lime water, or a weak alkaline solution. When well washed, the benzol will suffer no change of colour on addition of sulphuric acid. The sulphuric acid may be used afterwards for the treatment of crude naphtha. The benzol ia then carefully distilled. To avoid the loss due to heating, the sulphuric acid is added slowly and at long intervals. The treatment with acid and alkali, and final washing with water, are best carried out in separate vessels ; by arranging them one above another, the liquids are easily decanted, and the sludge can be caught in receptacles placed beneath. Lime is cheaper than soda ; but it forms, with many of the tar acids, less soluble com- pounds, which are thus less easily removed by washing. The alkali waste from this and similar operations is now frequently burnt for reconversion. The amount of benzol contained in a sample of tar will, under ordinary circumstances, depend upon the amount of refrigeration to which the gas is submitted. The reader's attention is called to Lake's patent method of obtaining benzol from gas (No. 488, 1869) ; if the figures therein given can be sustained in practice, an enormous amount of benzol and toluol can by this method be recovered from coal-tar. Coal-tar naphtha boiling at 130 (266 F.) is worth about Is. 9d. a gall., whilst petroleum boiling at 149 (300 F.) is worth about 9c7. a gall. ; 60 per cent, benzol is worth 3s. a gall. If it is possible to recover, say, 12 per cent, of the liquid used in washing the gas, there should be 2J lo 5 gall, of a product worth from 3s. to 4s. a gall, from every 10,000 cub. ft. of gas, BO that it would be more economical to carburet the gas with such liquids if necessary. This fact is important to gas manufacturers, and not without interest to gas consumers. If the sole object in distilling coal were to use the gas as fuel, there could be no advantage in this process. It appears quite possible that, by selecting the coal and arranging the heats, the tar may be enriched in benzol, with only a slight sacrifice, in the quantity of gas produced. The production of liquid hydrocarbons from coal, as a source of profit, does not seem to have occurred to gas companies. The comparative poverty of the highly bituminous coals in benzol and anthracene places many dis- tillers of English tar at a disadvantage in the manufacture of these two products. Toluol, Toluene, or Methyl Benzol. C 6 H S ,CH 3 . Toluol was discovered by Pelletier and Walther in rosin-oil, and was called by them " Eetinnaphtha." The name " toluol " was given to the liquid by Deville, who obtained it by the distillation of Tolu-balsam. It exists in wood-tar ; but its commercial source is coal-tar. It is met with in commerce as '' rectified toluol," " commercial toluol," " rosaniline benzol," &c. Its highestdegree of rectification would be exhibited by the fluid obtained in preparing benzol by refrigeration ; but commercially it is procured from the distillate of naphtha which comes over between 107 and 121 (225 and 250 F.) ; some samples contain a dis- tillate going over at higher temperatures. It is a colourless, limpid, oily liquid, which does not solidify when cooled to any ordinary temperature. In odour, solvent properties, and miscibility with other hydrocarbons, it resembles benzol. By oxidation, it becomes benzoic acid. Its sp. gr. is 0-88 at (32F.),and -87 at 24(75F.); it boils at 110 (230 F.). The value of commercial samples is found in the same way as benzol. It is best stored in galvanized iron drums, or glass carboys, as benzol. Xylol, Xylcne, or Di-methyl Benzols. C S H 4 /^ Hs . When purified coal-tar napntha ICHj is submitted to fractional distillation, a liquid boiling at 139 to 140 (282 to 284 F.) is obtained. This was at first regarded as a pure compound ; but recent researches have shown it to be a mixture of two di-methyl benzols, which, having nearly the same boiling-point, cannot be separated by dis- tillation. They are known as " methyl-toluol " and " iso-xylol " ; the latter forms the principal ingredient of the solvent naphtha used by indiarubber manufacturers. Commercial xylol contains a little toluol, as it is the product of the higher distillation after the commercial toluols have been drawn over, and consequently forms the bulk of the second light oils. It is prepared by Beilstein and Wahlfoss by treating the naphtha distillate which conies over at 141 (286 F.) with fuming sulphuric acid, after repeated treatment with acid and alkali, as in preparing benzol, naphtha, &c. ; this dissolves the xylol, which is subsequently extracted by dry distillation. Creosote. The portion of the distillate which is collected as creosote oils is generally sold as "creosote," without any further treatment. It is a thick, black liquid, containing principally NAPHTHALENE. 649 carbolic acid and naphthalene. Its consistency varies with the propoition of the latter; creosote from London tar is particularly rich in it, and, in cold weather, frequently solidifies. The principal use to which creosote is applied is the preservation of timber. Its value for this purpose depends, according to Dr. Letheby, upon the following points: It should have a density of 1-045-1 -055; it should not deposit any crystalline matter at 4-5 (40 F.) ; it should not yield less than 5 per cent, of crude carbolic acid to a solution of caustic potash at 1'OTO (14 Tw.); and it should furnish 90 per cent, of liquid oil when distilled at 315 (600 F.). Some contracts issued jn 1867, by the Dutch Government, stipulated that the creosote should be clear, and not yield more than 40 per cent, of naphthalene when cooled to (32 F.), and kept at that temperature for twenty-four hours. It should dry up with little loss, and should harden by oxidation when imbibed by porous substances. This fraction is also worked on for carbolic acid. The creasote of the druggists is a totally different product, derived from the distillation of wood. Creosote oils accumulate in a works in excess of requirements ; they may be utilized as fuel, in accordance with the patented plan of Edward Dorsett (No. 176, 1868). Crude creosote is worth 21. to 21. 5s. a ton. Naphthalene. C 10 H g . This substance was discovered by Garden, in 1820, in coal-tar. It is formed by the destructive distillation of many organic bodies, especially when their vapours are passed through tubes heated to redness. It is found in wood-tar, and also in Rangoon petroleum ; it has been produced synthetically by passing the vapour of pheuyl-butene dibromide through a red-hot tube. Its commercial source is coal-tar. It exists most abundantly in tars from bituminous coals ; in lignite and boghead tars, and also the better classes of cannel tar, it is replaced by paraffin. In the distillation of tar for the production of crude naphtha, the process is arrested when a few drops of the distillate solidify on collection on a cool surface. The substance then left in the stills contains much naphthalene and phenol. Until anthracene received commercial importance, this residue was distilled for creosote oils only. The presence of naphthalene in naphtha is shown by the high sp. gr. of the residues at 160 (320 F,) , on evaporating these slowly in a water bath till the bulk is reduced one-half, and cooling, naphthalene is obtained ; when pressed so as to separate the adhering liquid, it will be found tolerably pure. It is sold in rolls, which are obtained by casting the melted article in moulds ; in this form, it is supplied for carburetting gas, by the method known as the albo-carbon. The further purification of naphthalene is effected in the following way. The material is first melted, in closed vessels, with a solution of caustic soda, and well agitated. Whilst boiling, the watery vapour carries away a considerable quantity of naphthalene, which should be collected ; as the vapours cool, it is deposited almost pure. The caustic solution and naphthalene are separated by cooling and compression ; after being well washed with boiling water, the latter is treated in a similar way with water acidulated with sulphuric acid. These operations are repeated according to the degree of purity required. It is then distilled in cast-iron retorts over a naked fire, at a temperature not much exceeding 205 (401 F.). The residue will contain much naphthalene ; but at higher temperatures, it is contaminated with other products. The distilla- tion is carried to dryness, and the last product is added to the crude naphthalene for re-treatment. Naphthalene crystallizes easily from saturated solutions, or by sublimation, in large silvery white plates or scales. It melts at 79 (174 F.) into a perfectly clear liquid, and, on cooling, solidifies into a crystalline mass. It boils at 216 (421 F.); its sp. gr. is 1-15. It is slightly volatile at ordinary temperatures. It burns with a smoky flame, being rich in carbon. It has been proposed to carburet illuminating gas with it, as already remarked. It is insoluble in water, alkaline solutions, and weak acids ; but is acted on by the stronger oxidizing acids. Alcohol, ether, wood naphtha, and the liquids obtained from coal-tar, dissolve it readily. With picric acid dissolved in warm alcohol, it forms a yellow solution which, on cooling, deposits beautiful yellow needles of picrate of naphthalene. This reaction is very characteristic. As naphthalene easily distils with the vapour of water, it may be purified by heating with water, on a water bath, or by passing a current of steam into the melted mass ; it condenses in beautiful pure scales on the sides of the receiver, which may be made of lead, and simply inverted over the other vessel. Pure naphthalene has been used medicinally : for the production of colouring matters, it is not necessary to carry its purification so far. The following plan is adopted by Calvert and Co. for producing it in a chemically pure state : The material is treated with rectified sulphuric acid, and heated in an iron pot ; it is well stirred, and then allowed to cool and settle, when it separates into two layers, one of naphthalene at the top, and a dark, tarry mass beneath. The upper portion is boiled by steam in an earthenware vessel, with frequent changes of water, until it is perfectly free from acid, adding a little weak soda to render it perfectly neutral. The naphthalene is then placed in a jacketed still, and distilled by steam-heat. The distillate is col- lected in a large receiver, and constitutes an exceedingly pure article. The production of red, scarlet, yellow, and violet colouring matters from naphthalene has given it some importance, still its production considerably exceeds its demand. The heavier oils being less important, manufacturers make the creosote oils contain as much naphthalene as possible. Only a few naphthalene colours have received much application ; generally they luck brightness, fresh- 650 COAL-TAR PRODUCTS. ness, and permanence. Still there is a wide field for attention to naphthalene as a source of colours; its price is considerably below that of any of the other products used for this purpose, and it is more than probable that an increased demand for it would tend to lessen rather than enhance its cost ; it is easily purified, and its compounds are readily obtained of the necessary purity. The general treatment of naphthalene and its derivatives for the production of colouring matters consists in direct oxidation into nitro compounds, from which, by reducing agents, &c., as with aniline, derived compounds are obtained : Nitro-naphthalenes. Four nitrated naphthalenes are known : the mono-nitro is obtained by boiling powdered naphthalene, or its solution in acetic acid, with ordinary nitric acid, .for half an hour ; concentrated nitric acid yields two modifications of di-nitro; fuming nitric acid boiled with the (a) modification converts it into tri-uitro, of which there are three modifications ; two modifications of tetra-nitro are obtained by the continual boiling in nitric acid of the two previous corresponding bodies. Naphthylamine or Amido-naphthalene. C 10 H 7 .NH 2 . Two parts nitro-naphthalene and three of iron turnings are mixed, and acetic acid is added to cover the mixture, which should be heated so as to fuse the naphthalene. When the reduction is ended, the mass is distilled, water and acetic acid first come over, the receivers are changed, lime or soda is added to the residue, and the distillation is carried to dryness. The oily liquid which comes over solidifies, and is purified by dissolving in sulphuric acid and precipitating with ammonia, or, after adding soda in excess to the sulphate, dis- tilling with steam. It crystallizes in colourless needles, melting at 50 (122 F.); it boils at 300 (572 F.) ; its hydrochloride heated with aniline to 280 (536 F.) for thirty-six hours gives uaphthyl- phenylamine or phenyl-amido-naphthalene. Amido-azo-naphthalene, N 2 |^ lo g 7 .NH 2 , is produced by adding potassium nitrite to a solution of amido-naphthalene hydrochloride. It crystallizes in orange needles, with a beetle-green lustre ; its salts, which are decomposed by water, have an intense violet colour. It dyes silk a fine orange, turning purple when dipped into hydrochloric acid, and becoming again yellow when washed with water. Sulpho-acids of Naphthalene. When naphthalene is heated with concentrated sulphuric acid, three sulpho-acids are formed, viz. : monosulpho-naphthalic acid, of which there are two modifica- tions (a and 0), and bisulpho-naphthalic acid. By heating 5 parts naphthalene and 4 parts acid for some time in a salt-water bath, the mixture will contain principally the o modification of the mono-acid ; but if the heat is carried to 116-118 (240-245 F.), it will yield the modifica- tion. The acids are first freed from the unaltered naphthalene, by pouring the boiling mixture into a large quantity of water : the naphthalene separates out on cooling ; the excess of sulphuric acid is removed by boiling with a little chalk, filtered to remove the sulphate of lime ; the filtrate yields crystals of sulpho-naphthalic acid on concentration ; the acids are separated by conversion into lime salts, the latter being difficultly soluble, whilst the former remains in the mother-liquor. The disulpho-acid is obtained by heating for several hours 1 part naphthalene and 5 acid. The removal of the sulphuric acid can be effected by oxide of lead, the sulphate of lead being insoluble, whilst the sulpho-naphthalic salts are separated by their differences of solubility in water and alcohol. The free acids are obtained by decomposing the lead solutions by sulphuretted hydrogen. These acids form the starting-point in the production of several compounds which have been worked upon more or less for tinctorial products. The conversion of these acids into naphthalic alcohol, or uaphthol, is thus accomplished : Sulpho-naphthalic acid is neutralized with potash, after separation of the unaltered naphthalene; the salt thus obtained is fused with caustic potash or soda ; by the addition of dilute acids to the aqueous solutions, the naphthol is precipi- tated in a crystalline form, of which there are two modifications, corresponding with the sulpho-acids. Naphthalene Chlorides. Naphthalene melts and absorbs chlorine when the latter is passed over it ; the dichloride, which is first formed, is a heavy pale-yellow oil ; by repeated distillation, and the action of alcoholic potash, it is resolved into hydrochloric acid and mono-chloro-naphthalene. The continued action of chlorine converts the dichloride into tetra-chloride. {Ol (CD ' * 8 obt^ 116 *! kv dissolving naphthalene in concentrated hypochlorous acid. Naphthalene, treated in the cold with a mixture of hydrochloric acid and chlorate of potash, is transformed into naphthalene dichloride, and di-chloro-naphthaquinone. Phthalic Anhydride. C 8 H 4 O,. This is produced by the action of nitric acid on dichloride of naphthalene. When the dichloride of naphthalene is treated with boiling nitric acid, it dissolves slowly, with evolution of nitrous acid. The solution deposits crystals on cooling. These crystals are purified by recrystallization from boiling water : the mother-liquor contains oxalic acid. Pure phthalic acid crystallizes in white nacreous lamins?, arranged in rounded groups. It is sparingly soluble in cold water, but dissolves easily in alcohol and ether. By distillation, it is converted into phthalic anhydride. Anthracene, or Paranaphthalene. C H H lo . This substance is the last product of com- ANTHRACENE. 651 mercial importance obtained in the distillation of tar. It commences to go over at about 171 (340 F.), and as the temperature is raised, it is contaminated more or less with the heavier oils ; this constitutes the *' Green oils." In its crude state, it contains naphthalene, phenanthrene, creosote, &c., from which it is separated, iu the first instance, by straining, and finally, when it is well drained, by submitting it to pressure. It is then in the form of flat, irregular pieces, about 1 in. thick, with a slight greenish colour ; exposed to the air, it changes colour, passing to a dirty-brown. The percentage of anthracene in this crude product is about 30. A great difficulty in its purifica- tion arises from its being nearly insoluble in ordinary solvents. It may be freed from the greater part of the liquid oils by means of a filter press. The same end is attained by pumping it up into bags, suspended over a shallow tank; when well drained, air is pumped through, and forces out a further quantity of the adhering oily liquids. On a small scale, these oils are driven off by centrifugals. In the treatment of green oils for recovery of anthracene, the following method is usually followed on the large scale, though slight modifications may be made according to the plant employed, and the degree of purification required. The oils are completely cooled ; this facilitates the separation of the anthracene, and reduces the solvent action of its associated oils, so that they present the appearance of a soft buttery mass, in which are scattered, more or less, grains of anthracene, which may even give the mass a granular aspect. They are pumped into a series of pipes a, 6 (Fig. 483), furnished with ~[" pieces opening at the bottom, and to which are attached strong canvas or flax bags d, to receive and filter the oils. These bags are 3 ft. or 4 ft. long, and are stitched with packthreads, which can be drawn out, so as to open them lengthwise for the removal of their contents. The pipes are 4 in. diameter; the "J" pieces may be 8 or 10 in. apart; at the end of each, is a collar c, for attaching the bags. A shallow tank e receives the liquid filtering from the bags, and returns it to the stills or the store tanks. At first, a large quantity of liquid comes away ; after a short time, the bags are well distended by the oils being forced into them. As the solids accumulate, the liquids cannot so freely escape; they are then allowed to drain for some hours, after which they are removed to a powerful hydraulic press, which squeezes out a further quantity of the liquid oils. Since the adhering oils, when heated, readily dissolve the anthracene, cold pressure must be first used, to remove the liquids ; hot pressure may be employed to complete the operation. The whole treatment of crude anthracene is open to very great improvement. Crude anthracene submitted to the same process of refining will have a higher percentage in summer than iu winter, because of its diminished solubility in the adhering oils. It is further purified by being very finely powdered, and agitated with about 25 per cent, of high boiling naphtha, or "solvent," (petroleum, is sometimes used instead), submitted to straining, pressing, &c., as before. The washing increases its percentage value from 20-25 to 30-35. The washing process is repeated two or three times, in closed iron cylinders fitted with mechanical agitators. The principal aim is to obtain the anthracene as finely divided as possible, and to bring every portion well into contact with the naphtha. For the final washing, the anthracene is sublimed, so as to obtain it in as fine a powder as possible. Anthracene from Pitch. It has been proposed by Fenner and Versmann (1871), and Lucas (1872, No. 747), to obtain it by distilling pitch to coking. Whether this can be made a profitable operation must depend upon the quantities obtained ; some coals yield considerably greater quantities of anthracene than others. Kopp says that the soft pitch from the gas used in Turin contains as much as 4 or 6 per cent., which is three or four times the amount present in tar. It has been suggested to distil soft coal-tar pitch with superheated steam, for the production of anthracene, and this plan has been tried on a working scale with varying success ; but the process does not appear to be carried out to any great extent, though it is one which commands attention. In distilling pitch to coking, certain disadvantages are said to arise. Anthracene is drawn over between 171 and 371 (340 and 700 F.), and the stills are emptied whilst the residue is still liquid. If the distil- lation be carried to coking, the distillate will contain much chrysene and pyrene, from which it is best freed by a second distillation. It is well to maintain a partial vacuum in the still by exhausting the vapours. A current of superheated steam blown through the still does not appear to act so well as exhaustion, though probably it is more convenient in most cases. Large quantities of anthracene are now obtained thus , the main precautions are to keep the stills supplied with melted pitch to one constant level, and, as the heavy vapours do not rise, to bring down the still head as near as possible to the surface of the pitch, and to surround the condensing pipes with boiling water ; the vapours are assisted over by suction or blowing. In most cases, the pitch is run into the stills direct from the tar stills. The plan adopted on the Continent is to coke the pitch in ovens or retorts of clay ; on opening them, the coke which is formed is burnt off. The preliminary washings, &c., are the same as before ; but a little more care is necessary. The liquids which are 652 COAL-TAR PRODUCTS. collected from the crude anthracene are frequently added to the creosote oils ; but as they are always saturated with anthracene, some method should be adopted for its recovery. The principles associated with crude anthracene are phenantrene, C U H 10 ; chrysene, Ci 8 H 12 ; pyrene, G 16 Hi . No colouring matters are at present made from these substances, although they yield compounds which may eventually become sources of profit in this direction. When the oils recovered from the crude anthracene are distilled, there remains in the retort, after the anthracene has been drawn over, a soft tarry residue containing much chrysene and pyrene; this may be mixed with the creosote oils, or, if burnt in suitable chambers, may be a source of a black pigment for which the " last runnings " are frequently employed. These residues are frequently, and with greater advantage, added to the pitch, for making softer kinds. It may be worth while to point out, that tars differ widely as regards their richness in anthra- cene ; as a rule, those which yield much benzol will be the best, and probably this fact may be usefully applied by gas companies who are interested in working up their own refuse. There are many natural bitumens in which benzol and anthracene exist ; and it is not improbable that an examination of petroleum residues may lead to some important additions to the list of dyeing pro- ducts. The amount of anthracene contained in a sample of the crude article is of great importance, since it is always sold by analysis. Its point of fusion will approximately indicate the amount of the oily impurities ; these may be absorbed by pressing between blotting-paper in a hot-press. The anthracene may be washed with cold alcohol, which will further free it from naphthalene and other oily matters. The melting-point of the product will give a very fair idea of its purity ; that of pure anthracene is about 210 (410 F.). The only method practically used for valuing samples of anthracene is Luck's anthraquinone test. A wide-mouthed flask of sufficient capacity has a wide glass tube 3 ft. long fitted into it with a cork ; the upper end of the tube is open, and carries a funnel furnished with a stop-cock, which regulates the flow of chromic acid solution. The whole is supported on a stand over a Bunseu's burner, and protected with wire gauze. One gramme of anthracene is dissolved, by boiling with 45 c. c. glacial acetic acid, in the flask ; 10 grm. chromic acid, free from lead, in 5 c. c. glacial acetic acid and 5 c. c. water, is added gently by the funnel, so as not to disturb the steady boiling, which is continued until a distinct and permanent greenish-yellow colour appears, or until a drop of the liquid produces a reddish spot on a piece of silver foil. It is then cooled, and gradually diluted with 150 c. c. water ; the anthraquinone is precipitated, collected, and washed with water on a filter, then with hot dilute potasli Jye, again with water, dried at 100 (212 F.), and weighed on the filter, which is afterwards weighed and deducted. The operation lasts four to six hours. To the net weight is added '01 grm., as, by Luck's experiments, this quantity is taken up by the acetic acid and water used. The un- oxidized impurities are thoroughly removed, by adding drop by drop, until the red colour does not vanish, a solution of permanganate potash to the residue on the filter; after washing it off into a beaker, oxalic and sulphuric acids are added, to remove the excess of permanganate; the whole is thrown into the same filter, washed to remove the acid, &c., then with dilute boiling soda lye and water, finally dried at 100 (212 F.) as before. Sand and other fixed impurities are determined by incineration. Purification of Anthracene. For final purification, anthracene is submitted to distillation, and the product coming over between 332 and 349 (638 and 660 F.) is collected. The distillate will contain a little anthracene before it reaches these temperatures ; but as the object is to obtain the article free from impurities, it is better to collect the distillate between temperatures which will allow the maximum quantity to come over. In the distillation of anthracene, there is always formed a large quantity of tarry matter, resulting from the decomposition of a portion of the anthracene, so that as little heat as possible should be used. The best way of conducting this operation is to place the partially purified anthracene in an iron Q retort, set in brickwork, and heated by a furnace immediately underneath ; as soon as the contents boil, a current of deoxidized air or steam is blown through ; this carries the anthracene into a closed chamber, where it con- denses. Preference is given to steam : air carries the sublimate over dry, but is liable to oxidize it. The sublimate is dissolved in recently-drawn naphtha, boiling at 121-149 (250-300 F.)} the naphtha is saturated at the boiling-point, and, on cooling, deposits the anthracene in crystals, which are drained, strongly pressed, dissolved in alcohol, and recrystallized. They still possess a slight yellow colour, which it seems is not entirely removed by redissolving and crystallizing ; but may be removed by washing with ether, or carbon bisulphide, or by carefully crystallizing from benzol with exposure to light. The pure crystals possess a fine blue fluorescence. Pure anthracene solidifies at 210-215 (410-420 F.), boils at 360 (680 F.); and evaporates slightly at its point of fusion ; its vapours have a disagreeable odour, and are irritating if inhaled. Alcohol and ether dissolve it sparingly ; benzol, readily, especially when heated ; in water, it is insoluble. It has been obtained synthetically ; and although the methods for obtaining it in this way are, at present, of scientific rather than of practical importance, still the high price of the pure article, and the demand for its derived colouring matters, are sufficient inducements for research in this direction. The present price of the crude article containing 60 per cent, anthracene is about 1501. a ton ; the value ANTHRAQUINONE. 653 of the pure article would be about 15/. a Ib. Improvements in the manufacture of this substance may be directed towards the prevention of loss in subliming or distilling ; it might be well to try the effect of the superheated vapours of benzol or naphtha injected into the retorts, instead of steam, for the anthracene might be much more economically sublimed, even if a little loss of an expensive solvent were incurred. A difficulty would be met with in the condensing ; but it does not appear insurmountable. Instead of the naphtha process, the article is sometimes purified at once by distillation with lime and caustic potash. There is a difference of opinion as to the merits of this process, as the coking which takes place with steam, even at high pressure, entails a great loss in working. Experience generally is in favour of the distillation with potash, and it is not improbable that, when this process has been unsuccessful, there has been a want of proper precaution in heating the retorts, for as a rule, bodies volatilizing at very high temperatures require much more care, and whilst superheated steam may admit of easier adjustment, it is probable that extra care with the potash process would be compensated for in the yield. ANTHRAQONONE, or OXYANTHBACENE. C U H 8 O 2 . By acting upon anthracene with oxidizing agents, anthraquinone is produced. Bromine, nitric acid, and chromic acid, have been employed for the purpose. It is obtained by the action of chromic acid, set free by adding strong sulphuric acid to a solution of bichromate of potash ; the anthracene is dissolved in boiling acetic acid, or more generally in ordinary oil of vitriol free from nitric acid, and diluted with twice its bulk of water, in lead-lined vats. The bichromate is gradually added to the solution, when the heat produced is sufficient to bring about the complete reaction. When acetic acid is used, some method must be adopted for its recovery. The anthraquinone is precipitated by the addition of water, and well washed ; it separates in the form of light, silky, almost colourless needles, which are dried in thin layers on trays, ready for subliming ; the retorts used are similar to those for subliming crude anthracene. On the large scale, thoroughly purified anthracene is converted into anthraquinone, by placing it with a little water in large lead-lined wooden vats, adding bichromate potash, or chromic acid, boiling, and adding sulphuric, acetic, or nitric acid. The boiling is continued for several hours, or even a day or more, by injected steam, which gives the requisite agitation. It is then allowed to settle, and the clear liquid is siphoned off; the precipitate is well washed for some days with boiling water, and after settling and cooling, the water is again drawn off, and received in other tanks for further subsidence for several days. The washed anthraquinone ia dried in a filter press, and is then a yellowish-white, silky, crystalline powder. The solution of the chromium salts is recon- verted into bichromate, or used in making chrome-alum. The methods which have been proposed for converting anthracene into anthraquinone are : (1) Anthracene, 1 part ; bichromate of potash, 2 parts ; concentrated acetic acid, 10-15 parts ; heated in a clay or glass vessel at 100-120 (212-248 F.), till nearly all the bichromate is dissolved, and the liquid has acquired a deep-green colour. (2) Acetic acid is replaced by sulphuric acid diluted with 1-2 parts water. (3) Anthracene, 1 part; glacial acetic acid, 10 parts; heated to 100 (212 F.) ; nitric acid (sp. gr. 1-3) is added in small portions at a time till the violent reaction ceases ; the acetic acid is partly recovered by distillation. The objection to nitric acid is the alleged formation of nitro- compounds, which is said not only to impede the purification of the product, but involve a loss, from the conversion of the anthracene into compounds incapable of yielding alizarine. (4) The method proposed by F. Baeyer, to heat anthracene with 5 parts manganese to 200 (392 F.), answers very well on a small scale, and yields the sublimed anthraquinone at one operation. The crude anthraquinone thus obtained is washed with water, dried, heated with sulphuric acid to 120 (248 F.), and the carbonized matter is removed by washing and filtering. The anthraquinone is thus raised to 93-96 per cent., and is purified by sublimation in iron retorts fixed over a naked fire, the sublimate being blown over into the subliming chambers by superheated steam. Much of the substance is decomposed and leaves'a fine hard coke, the loss being about 30 per cent. This coke is, according to Bolley and Kopp, rich in chromium oxides $ it may therefore be possible that the loss is due to imperfect washing of the anthraquinone : on the small scale, it sublimes without leaving any residue, which may be attributed to the more easily controlled heating, and may suggest its being sublimed on a large scale by supplying it continuously to the retorts. The sublimate has a fine, silky, crystalline texture, a light-yellow colour, and contains streaks of reddish, crystalline matter. It is dried on canvas in heated rooms, and mixed by sifting, when it is ready for conversion into bromo-, chloro-, and nitro- compounds. Dibromanthraquinone, C U H 6 B 2 (O. 2 ), is formed by the direct action of bromine on anthraquinone at 160 (320 F.) ; it is more conveniently made from tetra-brom-anthracene, one part of which is heated with two parts chromate potash, and 5 to 6 parts colourless nitric acid, sp. gr. 1-4, in a large flask, as the action is very violent at first, and the liquid frequently froths; the action is complete as soon as bromine vapours cease to escape. It is mixed with water, and the pale-yellow 654 GOAL-TAB PRODUCTS. mass is collected on a filter, washed, and recrystallized from benzol. The oxidation succeeds as well with glacial acetic and chromic acids. Dibromanthraquinone crystallizes in light yellow needles, and sublimes unaltered in the same form. Sulpho-compounds. Anthraquinone heated with sulphuric acid and mercuric nitrate, and the product treated with soJa <>r potash, produces disulpho-anthraquinonic acid. Anthraquinone, and sulphuric acid (sp. gr. 1'848), in the proportions of 1 to 3 parts by weight, are heated in a glass or porcelain retort at 260 (500 F.) till the former is completely con- verted, as shown by its complete solution in water. The mixture is then left to cool, and diluted with water, and the excess of sulphuric acid is removed by the cautious addition of carbonate lime ; the sulphate is removed by filtration, and the filtrate is treated with carbonate soda or potash, to remove any traces of lime ; the evaporation of clear solution leaves the sulpho-acids of anthra- quinone combined with the alkali. It has been found that there is no need to convert the anthracene first into anthraquinone ; the same results are attained by converting anthracene into sulpho-anthracenic acids, and then oxidizing into sulpho-anthraquinonic acids. Anthracene, and sulphuric acid (sp. gr. 1-848), in the proportion of 1 to 4 parts by weight, are heated for about three hours at IOU (212 F.), and the heat is then raised to 149 (300 F.), and maintained till an entirely soluble product is obtained. This is diluted with about three times its weight of water, and to the solution is added, for every 1 Ib. anthracene employed, 2-3 Ib. manganic dioxide, so that on boiling, the oxidation may be complete. The free sulphuric acid and oxide manganese are removed by milk of lime, which is added till the reaction is alkaline; carbonate soda or potash, added to the filtrate, removes the lime, and yields the alkaline salt in solution. Peroxide lead, chromic acid, nitric acid, or other acids capable of effecting the desired oxidation, may be employed. It is necessary, however, if the oxidant be soluble, to remove its excess before carrying out the second part of the process : nitric acid may be driven off by evaporation ; chromic acid, and peroxide lead, may be acted on by a current of sulphuretted hydrogen, or sulphurous acid. According to another plan, anthracene, 1 part, and sulphuric acid, 4-6 parts, are boiled for some time, diluted with water, and neutralized with carbonate lime or baryta, or caustic alkali; the resulting sulphates of lime or baryta are removed by filtration, and the clear solution is heated at 180-200 (356-392 F.) To convert anthracene into chloro-anthracene, and afterwards into sulpho-anthraquinonic acid, the anthracene in fine powder is spread out, in contact with chlorine, on leaden trays, for about twenty-four hours ; this crude dichlor-anthracene may be used at once, or after purification by crystallizing from benzol. One part of it is mixed with 4-5 parts fuming sulphuric acid, and excess of binoxide manganese, and the whole is heated at 112-149 (234-300 F.) till it will dissolve in boiling water. The product is diluted with three or four times its bulk of water, and well boiled with excess of binoxide manganese, till the diluted solution does not appear fluorescent ; it is then poured off, and milk of lime is added until the solution is alkaline ; the whole is well boiled and filtered, and the residue on the filter is well washed. The filtrate is concentrated, and carbonate potash or soda is added until all the lime is precipitated. Nitro-compounds. Meister, Lucius and Briining's method of oxidizing anthracene into anthra- quinone by nitric acid, with formation of nitro-anthraquinones, is objected to as causing a serious loss; the fact, however, of this patent (1872, No. 2649) being extensively worked in England con- tradicts the existence of any great obstacle, even if a loss can be established ; and it is not improbable that the loss (if any) has been due to impurities and their subsequent elimination, or intermediate reaction due to their presence ; probably the use of nitric acid in such quantities as to produce only mono-nitro-anthraquinone may explain why nitric acid has not been an advan- tageous oxidizer. Highly purified anthracene, melting at 207-210 (405-410 F.), is heated for some time with a mixture of bichromate potash and dilute nitric acid ; the product is boiled for three hours with six parts by weight of fuming nitric acid (sp. gr. 1 -50) ; this yields a yellow solution ; from this, after boiling, and addition of water, is formed a yellowish precipitate, which consists principally of dinitro-anthraquinone. The acid liquor is filtered off; and may be used in the oxidation of a further quantity of anthracene. NITRO-BENZOLS ; NiTKO-TOLUOLS ; NrrEO-XTLOLS. Benzol, toluol, and xylol dissolve in nitric acid, with evolution of heat ; on the addition of water, the nitro-compounds are obtained, as heavy oily liquids. By boiling benzol with strong nitric acid, or with a mixture of strong sulphuric and nitric acids, dinitro-benzol is formed. Toluol forms two isomerides with nitric acid, which are separated by distillation: 1'4 nitro-toluol melts at 54 (129 F.), and boils at 237 (459 F.); l'2nitro- toluol does not solidify in a freezing mixture, and boils at 223 (433 F.). Dinitro-toluol exists in two forms : the first is produced by acting on 1 4 or 1 2 nitro-toluol, with hot concentrated nitric acid, and crystallizes from alcohol in long, colourless, brittle needles, melting at 71 (160 F.); the second is obtained from 1 3 nitro-toluol, with concentrated nitric acid, and forms long, yellow needles, melting at 60 (140 F.). Xylol, or iso-xylol forms similar compounds : nitro-isoxylol is a NITEO-BENZOL. G55 pale yellow liquid, boiling at 239 (462 F.) ; the dinitro compound crystallizes from alcohol in long, brilliant prisms, melting at 93 (199 F.) ; the trinitro forms colourless crystals, melting at 177 (351 F.). Before nitrating toluol and xylol, it is important to wash out all traces of the heavy oils, in the same way as from naphtha and benzol (q. v.), otherwise explosive compounds may be formed. Nitro-benzol was first made on the large scale by Collas, at Paris, and was sold under the name of " Essence of Mirbane." It is generally prepared by the action of two parts fuming nitric acid and one part concentrated sulphuric acid ; the benzol is placed in the still, and the acids are gradually added, with agitation ; the nitric acid must be applied slowly, until red fumes appear. The end of the reaction is indicated by the liquid becoming colourless, or nearly so, and separating into two distinct strata, on the addition of water. Figs. 484 and 485 represent one of a series of apparatus described by Perkins (Cantor Lectures) as being used for its manufacture in this country : a, cast-iron pot standing on brickwork ; b, outlet for finished product ; c, inlet for raw materials ; d, an iron pipe to carry away nitrous fumes, connected with a condenser for collecting the benzol which is evaporated; e, spindles of etirrers, worked by toothed gearing, and entering the pot through a water-lute supplied with nitro-benzol ; the pots are cooled by water flowing over them, as at /. The use of the sulphuric acid is to take up the water which is formed, thus keeping the nitric acid undilute, and preventing action on the pot. When b is opened, a mixture of acids first runs out; then the nitro-benzol, which is washed and distilled, if necessary. Washing may be effected in closed cast-iron tanks, sup- plied with exhausters, for drawing off the nitrous fumes, and, at the bottom, with a per- forated serpentine coil for conveying lime water, or water, in the form of fine spray. The final washing is made with water, but the presence of a little lime is not detrimental. Distillation should be performed by steam. Nitro-benzol has generally a brown colour, but -when quite pure, is a pale-yellow, strongly- refractive liquid, boiling at 220 (428 F.) ; it has a burning sweet taste, and a smell resembling that of oil of bitter almonds and cinnamon ; its specific gravity is about 1 200. Nitrate of soda is sometimes used instead of nitric acid ; in this case, the sulphuric acid added must be sufficient to convert the soda into the acid sulphate. The advantage is the comparative inexpensive production of concentrated nitric acid. The same apparatus is applicable. When properly made, the yield of nitro-benzol should be 130-135 per cent, on the benzol employed. Three kinds are met with in commerce : " Light," boiling between 204 and 210 (400 and 410 F.), constituting the " essence of mirbane," and used for scenting common soaps, and in low-class perfumery; "heavy," boiling between 210 and 220 (410 and 428 F.), possessing a fatty smell and rather dark colour, used chiefly for the preparation of aniline reds ; " very heavy,'' boiling between 221 and 235 (430 and 455 F.), with disagreeable smell, and chiefly used for colours requiring high-boiling anilines. The essence of mirbane is sold as artificial oil of bitter almonds. Aniline. C 6 H 5 .NH 2 . This substance was discovered in 1826, by Unverdorben, who obtained it from indigo, hence its name, anil, being the Portuguese for indigo. It exists in the heavier tar- oils ; but its extraction from them is a matter of scientific curiosity rather than of commercial importance, and its quantity is too small to compete with nitro-benzol. By the action of reducing agents, nitro-benzol is converted into " aniline," or " amido-benzol." The process generally used for the commercial production of aniline, is, with slight modifications, that known as Be'champ's. In a capacious retort are mixed 1 part by weight of nitro-benzol, 1 2 part of iron-filings, and acetic acid (1'068 sp. gr.) equal in volume to the nitro-benzol. A reaction immediately com- mences, with active effervescence, accompanied by a rise of temperature. To prevent the passing over of the acetic acid, it is well to cool the retort. Whatever may have passed over should be returned, and, after a little time, the distillation may be begun. The product will consist of aniline, acetate of aniline, and acetaniline, the last appearing towards the end of the operation. A little milk of lime, or potash, added before distilling, will greatly prevent the passing over of the two last. By using acetate of protoxide of iron, the action has been rendered less energetic, and more controllable. The yield of aniline will be 60-65 per cent, on the nitro-benzol used. The main points in the commercial production of aniline are practically the same ; but scarcely 656 COAL-TAR PEODUCTS. two manufacturers adopt the same details. The superiority of many of the aniline colours depends upon the quality of the aniline employed, which is generally subjected to one or more rectifications. This is performed by distilling, and collecting the distillates separately, the portion richest in benzol- aniline being collected between 182 and 199 (360 and 390 F.). It is difficult, by fraction izing, to free aniline from toluidine, consequently high-class benzols should be used for low-boiling anilines. Some manufacturers reduce the nitro-benzol to crude aniline in separate vessels, and distil in special retorts ; this is not necessary, and the two operations are usually performed in the same vessel. A great advantage in this consists in obtaining the aniline at one operation ; the unaltered benzol is collected, and returned to the still, until the reduction is complete, when direct heat may be applied, and the aniline may be drawn over sufficiently pure without further rectification by distilling, unless for the very finest class anilines. In this case, a little lime is thrown into the still before drawing over the aniline. Much depends upon the extent of the operations : a method which would be far from economical on a small scale, may be the only one practicable on an extensive scale. On a small scale, it is better to work with nitro-benzol suited to the special description of aniline required, and to work it off in one still, as shown in Fig. 486. A cylindrical still A is fitted into masonry, with a furnace so constructed as to avoid direct action of the fire. Through the cover, which is bolted on, passes the spindle a of the agitator 6, which rotates during the whole time that the conversion is going on ; a bent tube or still head c, fitted to the cover, conveys the vapour to a properly cooled condenser. Be- fore the -cover is bolted on, it is usual to put into the still the required quantity of iron- turnings, otherwise a suitable opening d must be left, especially for continuous working, to avoid removing the cover every time the still is filled. A small opening e, provided with a stop-cock, and communicating with the nitro-benzol reservoir, enables this liquid to be delivered as required, at or near the bottom of the vessel, so as to avoid its evaporation before coming into contact with the iron-turnings. A quantity of acetic acid is poured over the turnings, either all at once, or gradually. It is sometimes replaced by hydro- chloric acid, whose more energetic action requires it to be added more cautiously. The heat gene- rated will drive some unaltered nitro-benzol into the condenser ; this should be poured back again. The agitator should be worked gently, and at intervals, as required. As the nitro-benzol is added, the heat increases, and when no further augmentation of heat is perceived, the reaction may be considered almost complete ; this, how- ever, will depend upon the way in which the operation has been conducted. The main pre- caution is the prevention of volatilization, until the whole of the nitro-benzol is reduced ; in order to secure this more effectually, it is better to add the liquids alternately at intervals, and to keep them well cooled and agitated. When the liquids which pass into the condenser remain clear on the addition of hydrochloric acid, it may be assumed that all the nitro-benzol is reduced ; and the distillation may be com- menced, by lighting the fire under the still. The spindle a is hollow, so as to admit the steam from the pipe fg for distilling. A little care will remove most of the difficulties of the process ; and, by giving a little extra time for working off the charge, a product can be obtained, which, by one recti- fication, will yield an aniline of sufficient purity for almost any purpose. The aniline can be freed from the mass by occasionally stirring with the agitator. Crude aniline is generally fractionized by the colour manufacturer, who is often in a position to supply himself with anilines which he could purchase only at a highly enhanced cost. Aniline is a limpid liquid, with strong refracting power, colourless when pure, but generally of a pale-sherry colour, which rapidly turns brown on exposure to air and light ; it possesses an agree- able, aromatic, vinous odour ; it burns slowly and with a smoky flame, at ordinary temperati-es, but with great violence when strongly heated; its sp. gr. is 1-02 at 16 (61 F.); it boils at 182 (360 F.) ; it forms well-defined salts with acids, which furnishes a means of separating it from any unaltered benzol ; it is very poisonous ; its sulphate has been used medicinally. Commercial anilines are of variable character, and consist principally of aniline, para-toluidine, meta-toluidine, xylidines, and cumidines. Light aniline oils distil generally at about 162 (-360 F.), the heavy oils, above this point ; the term " aniline-tailings " is applied to the heaviest oils, of high boiling-points. Tables have been drawn up, showing the proportion of heavy and light aniline ANILINES. 657 eils for different shades ot colour ; but they are scarcely reliable. Reimann says that the best oil for "fuchsine" is that yielding 61 per cent, of distillate between 185 and 190 (365 and 374 F.), and 28-5 percent, between 190 and 205 (374 and 401 F.); Girard and De Laire state that the most suitable oils are those containing about equal quantities of true aniline and toluidine, and yielding 10 per cent between 182 and 185 (360 and 365 F.), 40 per cent, between 185 and 195 (365 and 383 F.), and 10 per cent, between 195 and 200 (383 and 392 F.) ; Kopp says the best " fuchsine " oils are those which almost wholly pass over between 185 and 210 (365 and 410 F.) ; while Hofmann found that various specimens of the oils actually in use on the large scale boiled between 182 and 220 (360^ and 428 F.). These anilines, or "aniline oils," as they are called, serve for the industrial production of the "aniline colours," or " toluidine colours," of which the principal are 1. Red: rosaniline or magenta, toluidine, xylidine, &c. ; 2. Blue : phenyl-rosanilines, dipheuylamine, toluidine, aldehyde, &c. ; 3. Violet : rosaniline, mauve, phenyl, ethyl, methyl, &c. ; 4. Green : iodine, aniline, leucaniline, chrysotoluidine, aldehyde, toluidine, methyl-aniline, &c. ; 5. Yellow, and orange : leucauiliue, phenylamine, &c. ; 6. Brown : chrysotoluidine, &c. ; 7. Blacks : aniline, toluidine, &c. ; 8. Greys. Aniline readily combines with the iodides and bromides of alcohol radicals ; it comports itself in this reaction like an " amine," and, for this reason, was formerly called " phenyl-amine." The names of these aniline products are made up of a prefix from the name of the alcohol employed and the terminal " aniline." ( TT Methyl-aniline. C 6 H 4 N < , . When aniline is mixed with methyl-iodide, a violent reaction sets in, accompanied by copious effervescence, so that on mixing it is best to agitate the vessel, to faci- litate the escape of the vapours ; on cooling, the mass solidifies into crystals of methyl-aniline hydriodide. It is also produced, together with dimethylamine, by treating aniline hydrochloride with methyl-alcohol under great pressure in a " cohobator." The base (methylanile) is obtained free? by adding caustic potash, and distilling. It is a colourless liquid, resembling aniline, and boiling at 193 (378 F.); it gives a blue coloration with bleaching powder ; and forms salts having a striking resemblance to aniline. The amido derivative of dimethyl-aniline, or dimethyl-phenylene-diamine, is converted into a blue colouring matter, by Caio (1877, No. 3751), by adding a solution of ferric chloride to the acid.fied and diluted solution, and passing a current of sulphuretted hydrogen, until the colour is produced. Ethyl-aniline. C 8 H S N .When anhydrous aniline and bromide of ethyl are mixed to- . gether, and slightly heated in a flask, so as to allow the bromide of ethyl which evaporates to fall back again into the aniline, the mixture soon boils, and, on cooling, becomes a crystalline mass. If this product is mixed with a solution of caustic potash, and distilled, there will be obtained a clear colourless liquid, readily turning brown on exposure to the air, and boiling at 204 (400 F.). It does not yield a violet colour with alkaline hypochlorites. Its salts are readily soluble, and with difficulty crystallizable. Di-ethyl-aniline. C 6 H S N(C 2 H S ) 2 . This is obtained by acting on mono-ethyl-aniline with bro- mide or iodide of ethyl in excess. At ordinary temperatures, the brom hydrate of di-ethyl-aniline requires four or five days to separate out ; it boils at 157 (315 F.). A simple cohobator is shown in Fig. 487 ; it consists mainly of a digester A, made of copper, for high pressures, and connected with a worm B, where all vapours given off are condensed, and, by opening the cock C and closing C', are fott returned to the digester: by closing C and opening C', they can be collected in D. G is a pressure gauge, and V, a safety valve. The cock S is opened for relieving pressure, or for distillation. The two parts of A, which are nearly spherical, are firmly bolted together. A steam pipe P admits steam, when neces- sary, to oarry off any of the products. When the whole of the materials cannot be placed in the digester at one time, a tube is fixed to the top, and is supplied with two cocks; the lower one is first shut and the upper one is opened, when a supply of the ingredients occupies the space between them; then by closing the upper cock and opening the lower one, the supply can flow in at any required rate. A pipe and stop-cock, communicating with the digester and tube, render the pressure the same in both when the upper cock is closed Poirrier and Chappat prepare alcoholized anilines without the use of iodine or bromine. Hydro- 2 658 COAL-TAE PKODUCTS. chlorate of aniline, or any other salt of this base or its homologues, and the alcohol of which it i desired to obtain the radical, are heated in a close vessel under pressure. Alcoholic salts and aniline may be treated in the same way, with the same results. Methyl-alcohol treated with the hydrochlorate of aniline requires 175-210 (347-410 F.) for three or four hours, and a longe period will do no harm ; but at 250-300 (482-572 F.), one or two hours will suffice. Hydrobro- mate, or hydriodate of aniline may be used, and requires only 100-200 (212-392 F.). The pro- portions are 100-150 parts alcohol to 100 parts aniline salt. The operation produces a salt of the new aniline base, according to the acid employed ; this salt is decomposed by soda or potash, and yields a mixture of alkaloids, containing one or more molecules of the alcohol radical. These are separated by fractional distillation. The portion passing over at or about 1P2 C (378 F.) is methyl- aniline (supposing methyl-alcohol to have been used), and that at 202 (396 F.) is di-methyl- aniline. The products above these points are methyl-toluols, -xylols, &c. ; corresponding to the quality of aniline employed. Aniline, 100 parts ; chloride ammonium, 80-100 parts ; and alcohol, 100-150 parts, heated to 275-300 (527-572 F.), for two or four hours, yield a liquid separating into two layers, of which the oily supernatant one is their new alkaloid. Mono-amyl-aniline. C 6 H 5 .C 5 H M .NH. A mixture of aniline and bromide-amyl is allowed to stand for a few days, when crystals of hydrobromate of amyl-aniline separate out ; these are decom- posed by potash, when the base is obtained free by distillation. It is a colourless, oily liquid, smelling of roses, and boiling at 258 (496 F.) ; it forms, with many acids, crystallizable salts, not easily soluble. Di-amyl-aniline. C 6 H s N(C 5 H n ) 2 - By heating the above at 100 (212 F.) with bromide amyl, crystals of hydrobromate of di-amyl-aniline are formed ; from these, the base may be obtained by distilling with potash ; it boils at 275-280 (527-536 F.), and yields sparingly soluble salts. Acetanilide, acetaniline, or acetyl-phenyl-amine. ^C S H 3 0} N. This substance may be obtained by H the action of acetyl chloride or acetic anhydride upon aniline, or by the distillation of acetate of aniline, hence its occurrence in crude aniline which has been distilled without lime. According to Greville Williams, it is prepared as follows : Glacial acetic acid and aniline are mixed in equal proportions, and distilled ; the distillate is returned till it begins to deposit in crystals near the outlet of the still ; when the receiver is changed, the head of the still is kept warm, and the distillation is proceeded with. The yield of acetaniline equals the weight of acetic acid employed. It is sparingly soluble in cold water, and crystallizes, from a boiling solution, in shining plates, melting at 106 (223 F.), and boiling at 292 (558 F.). It begins to volatilize at 100 (212 F.), and sublimes at 200 (392 F.). On adding 80 parts water to a mixture of acetaniline and aceto-toluidine dissolved in four parts glacial acetic acid, the aceto-toluidine precipitates by standing, whilst the acetaniline remains in solution. This may be conveniently employed for the separation of aniline and toluidine in the examination of a sample of aniline, when greater accuracy is necessary than can be obtained by fractionizing. Amido-azo-benzol. C 6 H S . N 2 . C 6 H 4 . NH 2 . This is produced by passing nitrogen trioxide into a warm solution of aniline, and by reducing mono-nitro-azo-benzol with ammonium sulphide. It crystallizes from alcohol in yellow needles, which sublime at a high temperature ; it is a weak base, forming salts of a red or violet colour. It is the commercial source of " aniline yellow " (q. v.). Tri-amido-azo-benzol. N 3 |p Ty 4 /NH \ ' "^ e hydrochloride of this base forms the principal portion of " phenylene-brown," or " Manchester-brown," which is manufactured by adding a solution of sodium nitrate to a cold solution of para-amido-azo-benzol hydrochloride. See pheny- lene-brown. C 6 H 5 | Diphenylamine, or Phenylaniline. C S H S > N. This is formed when a mixture of aniline and aniline H ) hydrochloride is heated under pressure. It is a crystalline solid, melting at 45 (113 F.), and boiling at 310 (590 F.) ; possessing a peculiar and agreeable smell ; and forming salts, which are decomposed by water. With nitric acid, it yields an intensely blue liquid. Hofmann obtained it by the dry distillation of triphenyl-rosaniline. It is found in the distillate at 280 -300 (536-572 F.), and, when mixed with hydrochloric acid, forms the solid chloride of diphenylamine, which is not soluble readily in this acid ; it is purified by washing in alcohol, and crystallizing in needles from its solution in petroleum spirit ; on exposure to the air, these crystals turn blue. By treatment with ammonia, it separates as a colourless, oily liquid, passing quickly into a crystalline Ditoluyl-amine, Phenyl-toluyl-amine,andDipkenylamine. These substances are prepared in awrought- iron spherical digester, supplied with safety valve, pressure gauge, thermometer tube, and a screw- plug, or large stop-cock connected with a condenser. The capacity of the vessel is about twice the bulk of liquids to be operated upon ; small quantities should be dealt with. About 70 kilo, anhydrous ANILINES. 659 aniline hydrochloride, and 50 kilo, aniline are heated together for two hours at 200 (392 F.), while the condenser is connected. The heat is gradually raised to 215-220 (412-428 F.) ; the outlet is then closed, and the heat is raised to 250 (489 F.), this pressure being 10-15J atmos. The operation lasts twelve hours ; during six hours, the heat is gradually raised from 240 to 260 (464-500 F.), and the pressure from 3 to 5 or 6 atmos. The yield should be 60-75 per cent, on the weight of aniline employed". The liquids which pass over consist principally of water and hydrochloric acid, aniline, &c., and are not returned to the digester. After cooling, the crude mass is dissolved in 70 kilo, cold hydrochloric acid, and the solution, filtered if necessary, is poured into 300-400 lit. water, and left to settle for twelve hours. The hydrochlorate of dipheuylamine is decomposed; the liberated base falls to the bottom, and the hydrochlorate of aniline, remaining in solution, is recovered by evaporation. The diphenylamine is first washed with a little boiling water, and then with a weak solution of caustic soda ; it is finally crystallized from its solution in alcohol, or light petroleum spirit. If toluidine and its hydrochlorate are t heated in the same way, ditoluylamine is obtained. When aniline or aniline salt is heated with toluidine or a toluidine salt, phenyl- toluylarnine is obtained. Commercial diphenylamine is thus a mixture of diphenyl-ditoluyl, and phenyl-toluyl-amine ; from it, diphenylamine blue is obtained, by oxidation or abstraction of hydrogen. Ditoluylamine gives a blue with a brownish-red tint, and phenyl-toluyl-amine gives a bluish or blue-violet; but a mixture of the two, in the proportions of 11 to 18, yields a fine pure blue. It is essential that the ammonia generated by the reaction should be removed from the digester ; otherwise a loss of 30-40 per cent, upon the product is incurred. Methyl-diphenyl-amine. (C 8 H S ) 2 NCH 3 . This base, according to C. Bardy (No. 376, 1870), is obtained by reacting upon diphenylamine or its salts, with methyl-alcohol, or its substitution products, at variable temperatures according to the substance employed. The product is treated with caustic alkali. Whatever process be employed, the new base is an oily substance, even at (32 F.) ; its boiling-point is near that of diphenylamine, from which it is very easily distinguished, by the fact that with nitric acid it develops a colour identical with that of permanganate potash. It is transformed into colouring matters, by treatment with any substance capable of eliminating hydrogen, whether directly or indirectly, to which reaction it very readily submits. Nitrate mercury at about 40 (104 F.), sometimes acts so powerfully that the mixture begins to burn. Perchloride iron, at about 100 (212 F.), rapidly transforms it into a resinous substance, of brownish-red tint, which, when dissolved in alcohol, becomes a pure blue. Heated to 190-200 (374-392 F.) with sesquichloride carbon, it quickly gives a resinous substance, which affords a reddish-blue colour when dissolved in alcohol ; hydrochloric acid precipitates the blue colour of the solution, while a violet colour remains in the mother-liquor. The proportions of the reagents may vary between wide limits without preventing the production of the colours. These latter are purified in the same way as aniline colours. Their solutions act directly as dyes. Methyl-benzyl-diphenyl-amine. Girard and De Laire (1869, No. 3675) thus prepare this sub- stance: in a digester, are heated 1J-3 parts chloride or bromide of benzol, or its homologues, with 1 part methyl-aniline or its homologues, at 210 (410 F.). By using a pressure of about 15 Ib. in the same apparatus, the proportions may be 1J : 2, the operation, in each case, lasting about three hours ; the same result is gained by leaving the mixture to itself for several days at the ordinary temperature. The product is purified by washing with caustic soda and water, and distilling if required. Toluidine, Toluylamine, or Amido-toluol. C 6 H 4 (CH 3 NH 2 ). There are two methods of obtaining this base on the commercial scale ; by reducing nitro-toluol, and by separating bases in commercial Aniline ; as the pure article is not required, the latter method is the one generally adopted, the product being more or less pure according to the limits between the fractionizings. Brimmeyr takes the fraction of commercial aniline which comes over in two successive fractionizings between 195 and 205 (383 and 401 F.), and separates the bases, first converted into oxalates. Eeimann divides anilines into two classes, light and heavy ; light or Kuph-anilines contain 90 per cent, aniline, 5 per cent, toluidines, and none of the higher homologues ; whilst heavy or Bar-anilines contain 70 per cent, toluidines, and 30 per cent, of the higher homologues. By mixing these or similar anilines together in different proportions, articles suited to all requirements may be produced. Heavy anilines are obtained from the nitro-compounds of low-class benzols containing much toluol; the lighter oil which comes over in rectifying, is kept apart for the light anilines. Generally, two distinct kinds of heavy anilines are prepared : one from the mtro-compound of rectified toluol; another from the nitro-compound of toluol, containing more or less xylol. As a rule, the lightest anilines give little advantage over the heavier medium oils, which can be produced at much less cost, and without much sacrifice in their qualities for colour-making. From such oils, it is always easy to obtain the lighter oils, for blacks, &c., by collecting what comes over in the manufacture of magenta, &c. The manufacture of anilines is not generally carried on at tar works ; but is more usually attached to a distinct branch of the business, in which the rectification of benzols, toluols, &c., forms the very important connecting link between tar-distilling and dye-making. 2 u 2 660 COAL-TAE PRODUCTS. Xylidine. This base may be formed from the nitre-compound of xylol, in the same way a aniline from nitro-benzol, as proposed by Be'champ. Hofmann and Martius have rendered it probable that coal-tar sylidine should be considered aa dimethyl-phenylamine, C 6 H 3 (CH 3 ) 2 NH 2 . Many other substances which exist in coal-tar and naphtha are intentionally omitted. With respect to the impurities and compositions of commercial anilines, a few words may be necessary ; so little is known of the influence of some of these so-called impurities, that it is impossible to direct a manufacturer in the rejection of an aniline, but it is easy to indicate for particular appli- cations what is required. An important fact to be borne in mind is, that aniline is not a definite compound to which chemical tests can be applied : purer tints and finer shades are often due to an accidental circumstance ; no manufacturer, without the strictest care, can always produce exactly the same anilines, and it is doubtful whether the cost of production would be justified by the advantages which are supposed to arise. There is a point, however, to which the attention of the colour manu- facturer must be directed : it frequently happens, with piece goods, that a singular variation of tint is perceptible even with the same vat of dye, and the same piece of fabric ; whether the dye- stuff, or fabric, or both combined, have to answer for this, ought to be determined, otherwise aniline dyes may have to bear the blame which should be laid on a careless dyer, or they may even be used to detect admixtures of different fibres. HosanUine. C 20 Hi 9 N 3 . A great number of colouring matters bearing the names aniline red, magenta, azaleine, rubiue, solferino, fuchsine, chryaline, roseine, erythrobenzine, &c., met with in commerce, are salts of this base in a greater or less degree of purity. By heating a mixture of aniline, toluidine, and pseudotoluidine with arsenic acid or other oxidizing agents, the crude colouring matter is produced. The proportions generally employed in this country are aniline commercial, 1 part ; arsenic acid, 75 per cent, dry acid, 1^-2 parts, by weight. On the Continent, 800 kilo, commercial aniline are mixed with 1370 kilo, solution arsenic acid, 72 per cent, dry acid. The quantity of water used must be such, that the arsenic acid solution does not deposit crystals on cooling. The aniline must contain a certain quantity of toluidine, and is known as " magenta aniline"; the most suitable for good rosaniline is that boiling beUeen 185 and 200 (356 and 392 F.). The most approved form of apparatus for the manufacture of magenta is that described by H. Cant, of the firm of Evans, Cant, and Co., of Stratford. It is shown in Figs. 488 and 489. Aniline and arsenic acid are introduced together into a U-shaped boiler with flat ends, heated by a furnace, and set so as to avoid direct action of the fire. The furnace door F, and ashpit door A, allow of very nice regulation of the draught, which is a matter of great importance. The ends of the boiler are left exposed, and in one of them is an aperture o, for emptying it ; through them passes the spindle of the agitator G, and at the top is an opening P, and a " goose-neck " of copper S, connected with a copper condensing worm, contained in a suitable receptacle, BO as to ROSANILINE. 661 collect the aniline and water given off during the heating. The great advantage of this arrange- ment is that the contents are removed by a small door, secured by wrought-iron bolts and wedges, and the framework of which prevents waste trickling down when emptying. The charge for these boilers should not be more than half the capacity of the boiler; the time required to work off a charge of 1200 Ib. aniline and 2200 Ib. arsenic acid is about eight hours. These proportions will yield approximately water, 730 Ib. ; aniline, 370 Ib. ; crude " magenta melt," 2300 Ib. It is necessary that the agitators be well worked even whilst the ingredients are being added, otherwise the mixture becomes solid, and has to be removed from the stills ; hence an advantage in using a large proportion of aniline proper. The fans of the agitators should be so arranged as to stir every portion of the mixture. Other oxidizing agents have been proposed, but none is so largely used as, nor more successful than, arsenic acid. The heating should not rise above 200 (392 F.). The heavier unaltered aniline is removed from the melt, before emptying, by distillation with steam. The melt is sometimes slightly moistened with steam, so as to make it leave the stills more rapidly. By knocking out the wedges which secure the small door, the melt is received in an iron pan (see Fig. 489) ; a piece of sheet iron, acting as a spout, prevents its trickling down over the furnace. The fire and ashpit doors being shut, the agitator is worked to assist its flowing out, the workmen then leave the spot so as to avoid the fumes. The aniline and water which come over are separated ; the aniline, recovered and rectified by distillation with a little lime, is best suited for all purposes requiring a low boiling aniline. The rosaniline is separated from the crude melt either by con- verting it first into a salt, or by first obtaining the base, purifying it, and then converting it into a salt. During the heating in the stills, a kind of humus is formed; this is removed from the colouring matter by boiling for four or five hours, with continuous agitation, in water heated by steam, with the addition of very dilute hydrochloric acid (7 Ib. commercial acid to 350 gall, water). The humus separates out, and the liquor is drawn off, and passed through flannel in a filter press : the filtrate contains hydrochlorate of rosaniline, arsenious and arsenic acids, and some chlorides of arsenic ; the addition of carbonate soda neutralizes the free acid, and the colouring matter is precipitated, with a little arseniate. An excess of hydrochloric acid facilitates the separation of the rosaniline salt. The rosaniline converted into hydrochlorate is purified as follows : a quantity of solution con- taining 1 ton of the crude salt is placed in a large iron tank, to this is added about 1 J ton of common salt, in small quantities at a time, and dissolved by a jet of steam let into the bottom of the tank by a tube ; the hydrochlorate is almost insoluble in the solution of common salt, and separates on the surface of the liquid, the arsenic and arsenious acids being retained in solution as arseniates and arsenites of soda. At the end of a few days, the colouring matter remaining in suspension collects on the top, as the liquid becomes cold, and is then removed. It is washed with a little boiling water, to remove adhering salts, and is then sufficiently pure for many purposes. Its further purification is effected as follows : It is dissolved in boiling water, filtered through flannel, and allowed to cool in large tanks, in which are suspended threads of wool ; at the end of several days, the salt has crystallized on the threads, and on the bottom of the tank ; the former is sold as " pure " or " refined," the latter is generally used for the manufacture of other dyes, as green or blue. The mother-liquor from a previous crystallization is generally used for dissolving the crude rosaniline after the separation of the humus; a crop of crude crystals is obtained, and the mother -liquor, which still holds much colouring matter in solution, is treated with milk of lime, to remove the arsenious and arsenic acids, so as to avoid the dangers of poisonous salts. Any colouring matter carried down with the lime is taken up by acetic acid. English rosaniline, made in this way, unless carefully crystallized, contains a little arseniate, which accounts for the bad effects produced on the skin by articles dyed with the impure salt. This fact proved very prejudicial to aniline dyes, especially for hose, a few years ago, and ought not to be overlooked by the manufacturers of tar colours. The advantages of this method are absence of acid fumes during the boiling, portability of salt as compared with hydrochloric acid, and economy of cost. The method most extensively adopted is to boil the crude magenta for several hours, with a large excess of lime, under pressure in an ordinary steam boiler, with perforated agitating fans closely arranged, so as to thoroughly break up the melt ; any unaltered aniline is thus carried away and condensed, the lime is converted into arsenite or arseniate (insoluble salts), and the rosaniline is obtained free by filtering whilst boiling hot. On cooling, a crop of impure crystals is deposited, the mother-liquor is repeatedly concentrated for fresh crops, or is used for boiling with fresh melt. It is better to exhaust the lime residues by boiling and washing than to extract the remaining rosaniliue by acids, as is frequently done. Wilson and Cant digest the crude base with commercial benzol, which takes up the resinous or gummy matters chrysaniline and chrysotolui- dine ; these are recovered by driving off the benzol, and, after purification in the usual way, are so A as " phosphine." The rosaniline is converted into hydrochlorate by the addition of acid ; an excess precipitates the salt for the finer class of dyes ; it is washed with solution of common salt, and recrystallized ; by repeating the operation, different qualities of dye are obtained. C62 COAL-TAE PEODUCTS. Treatment of Magenta Residues. In the ordinary manufacture of rosaniline, chrysotoluidine, mauvaniline, and violaniline are simultaneously formed ; the separation of these not only enables a manufacturer to enhance the beauty of his reds, but by their separation and purification, he obtains a great variety of colouring matters, at comparatively little expense. The separation of these bases depends upon their solubilities in the menstrua employed. In boiling hydrochloric acid, diluted with 2 times its bulk of water, rosaniline is nearly insoluble, while the other bases are readily soluble; on cooling, mauvaniline, and a little rosaniline, separate out as hydrochlorates. Chryso- toluidine is soluble in an acid solution of common salt, from which mauvaniline and rosaniline are precipitated. By neutralizing this solution with soda, chrysotoluidine precipitates (or violaniline) maybe separated from chrysotoluidine and mauvaniline ; by dissolving these bases in aniline, and just saturating with hydrochloric or acetic acid, the violaniline is precipitated ; the filtrate is diluted, and mixed with common salt, by which mauvaniline is thrown down ; caustic soda in excess preci- pitates chrysotoluidine, and the aniline is recovered by distillation. Girard and De Laire proceed thus : On boiling 1000 kilo, with 12,000 kilo, water, and 500 kilo, ordinary hydrochloric acid, the violaniline is taken up ; 125 kilo, of the same acid is added to the boiling filtrate, which, on cooling, deposits hydrochlorate mauvaniline, with a little rosaniline and resinous matter ; 625 kilo, common salt added to this filtrate throws down a little mauvaniline, and rosaniline salts ; the mother-liquor, treated with 83 kilo, carbonate soda, soon deposits salts of rosaniline, and a little chrysotoluidine; the further addition of 3?2 kilo, carbonate gives a precipitate consisting almost entirely of chrysotoluidine ; in this way, 5-10 per cent, of colouring matter may be recovered from the waste of the crude rosaniline. The separation is more easy and economical if all the rosaniliue be extracted by boiling, as for the crude article. The further treat- ment of these matters with acid, common salt, and carbonate of soda, will yield different colouring matters, which will be noted in their proper places. See Rosaniline, Violet, Yellow, and Brown. Leucaniline. C 20 H 21 N S . On boiling an acid solution of rosaniline with zinc, or mixing it with ammonium sulphide, it gradually becomes colourless, aud a yellow resinous substance is deposited. This is crushed, washed with water, and dissolved in weak hydrochloric acid ; the addition of strong acid precipitates the hydrochlorate of this base. Ammonia, added to a solution of this salt, yields the pure base, which is a white powder, easily soluble in alcohol. By oxidation, it yields brown colouring matters (q. v.). Geranosine. Luthringer has given this name to a red derived from magenta in the following way: 1 kilo, of the crystallized hydrochlorate is dissolved in 1000 lit. boiling water, filtered hot, and left to cool to 45 (113 F.); 4 kilo, anhydrous binoxide barium, powdered, and 35 lit. cold water, are stirred together in an earthenware vessel ; over this is poured 10 kilo, sulphuric acid, and the whole is well stirred for a minute or so. The solution of magenta is then added to this mix- ture, with agitation ; it instantly changes to a yellow citron colour, and, after 2-3 minutes, passes to a slight reddish tint. The sulphate and peroxide barium are separated by filtering, and the filtrate is allowed to cool. It is then placed in a wooden, or tinned copper, vat, and heated to boiling ; as the temperature rises, the red is developed, and reaches perfection at the boiling-point. It is boiled for two or three minutes, filtered, and left to cool ; the filtrate contains the geranosine, ready for use. Ulrich's Scarlet. A colouring matter very similar to the above is obtained from 4 parts acetate rosaniline and 3 parts nitrate lead, dissolved in boiling water, and afterwards evaporated to dryness. The dry mass is heated at 149-199 (300-390 F.) until it passes to a complete violet colour. After cooling, it is boiled for some time in water slightly acidulated with sulphuric acid. The solution is then neutralized with soda or potash, and filtered whilst boiling. The colouring matter passes into the solution, and may be separated by the addition of salt, recovered on a filter, washed, and dried. It can be made to yield a rose-red substance, by ethylation or methylation ; its solution in alcohol is mixed with iodide methyl or ethyl, and heated for some time in a closed vessel at 149 (300 F.); from the product, the colouring matter can be extracted in the same way as Hofmann's violet (q. v.). It is used for dyeing, in the same solvents. Safranine. This name is given to a colouring matter which has been used for some time for dyeing silk ; it gives a fine red colour with a tinge of scarlet. Amido-azo-benzol and amido-azo-toluol are oxidized by bichromate of potash, and the crude safranine produced is boiled in water containing soda or lime, in which the violet colouring matter is insoluble, whilst the safranine is taken up. The liquid is filtered, and slightly acidified with hydrochloric acid, by which the safranine is converted into hydrochlorate, and can be extracted by evaporation, and the addition of salt ; the excess of acid may be previously neutralized by carbonate lime. If required of greater purity, it may be treated with water rendered alkaline by caustic soda. The commercial article is a reddish-yellow powder containing hydrochlorate safranine, mixed with much carbonate lime and common salt. It can be readily purified by solution and recrystal- lization ; the final crystallization should be from a boiling and slightly acid solution. Pure safranine cannot be precipitated from its hydrochlorate solution by alkalies, in consequence of the formation of basic salts, &c., which are co-precipitated. The solution should be decomposed AESENIC ACID. 663 by oxide of silver ; the filtrate from this is deep yellow-red, and when evaporated and cooled, deposits red-brown crystals, very like the hydrochlorate, and which, dried at 100 (212 F.) take a light-greenish metallic lustre. The safranine dissolves easily in water and alcohol, but not in ether. Concentrated solutions, mixed with hydrochloric and many other acids, give immediate crystalline precipitates of the salts of safranine, all of which may be recognized by the fact that when con- centrated hydrochloric acid is added to their solutions, the reddish-brown colour of the liquid passes successively to violet, deep blue, deep green, and at last to a clear green ; when water is added gently to this solution, the same changes of colour take place in the reverse order. Sul- phuric acid acts in the same way as hydrochloric acid, and with more marked effect. See also rosaniline brown and yellow. Cerise. This name has been given to a red colour from rosaniline residues ; after precipitating the mngenta with common salt, and filtering the liquid, carbonate of soda is added to the filtrate, and the product is washed and dried. Cerise probably contains magenta, and a little of the yellow colour from chrysaniline and chrysotoluidine. It dyes a shade between crimson and scarlet. (See rosaniline residues and leucaniline browns.) Sopp treats the resinous residues of rosaniline with 70 or 80 per cent, of hydrochloric acid. The insoluble portion is afterwards boiled in water, and treated with nitric acid, which causes a black deposit, whilst a yellow substance is dissolved, and crystallizes out on cooling ; the hydrochloric acid solution first obtained is mixed with a sojution of carbonate soda, producing a dark green precipitate, which, boiled in water, yields a little rosaniline ; the green precipitate is well washed, and taken up by weak ammonia water and a little soap solution, when it gives a solution of very rich deep-red colour on cooling ; if redissolved in hydrochloric acid, it gives a violet-blue liquid ; it dyes shades which are wanting in beauty, but are solid ; when applied to wool and silk, passed through permanganate of potash, it is converted into a fine chestnut-brown. Arsenic Acid is manufactured on a large scale for this industry. The arrangement for the production of aqueous arsenic acid for magenta manufacture is thus described by H. Cant, of Evans, Cant, and Co. A series of stoneware pans A (Fig. 490) fit hermetically into an iron water bath B, heated by means of an iron coil. The pans are fitted with cemented covers, having two openings, in one of which a glass funnel F is placed, and to the other is securely attached an earthenware tube for leading away the nitrous oxide. Stoneware jars J, fitted with tubulures and stop- cocks, are filled with nitric acid (sp. gr. 1-400); the stop-cocks are opened so as to allow the acid to dribble slowly, as required, into the jars A, which contain arsenious acid mixed with a certain quantity of water. Thus the arsenious acid is expeditiously converted into arsenic acid of the degree of hydration required for magenta manufacture, whilst the nitrous fumes are collected in a series of large Woulfe's bottles. By means of an aspirator, these vapours are drawn out of the pans A accom- panied by air, and are thus oxidized into nitrous acid, and ultimately into nitric acid for re-use. An outlet near the bottom of the pans allows the arsenic acid solution to be drawn off as required. This method of producing arsenic acid, and converting the nitrous oxide into a profitable product, enables arsenic acid to be produced for a trifle more than the cost of the arsenious and nitric acids, and removes the objectionable features of the manufacture ; several attempts to utilize the refuse arseniates and arsenites, resulting from the manufacture of rosaniline salts, have been made, but with little success. Nicholson (No. 519, 1878) proposes nitric and hydrochloric acids, instead of arsenic acids, for the production of colours having rosaniline for their base. Three parts by weight of commercial aniline (such as is generally used for the production of red aniline dyes), about one part nitric acid (sp. gr. 1-420), and one part hydrochloric acid (sp. gr. 1-160), are heated at 177-204 (350- 400 F.) until the dusired colouring matters are produced; this is ascertained by withdrawing samples as the operation proceeds. The contents are removed, and the colouring matter is extracted by boiling water; it may be used direct, or purified; or the base, rosaniline, may be separated by means of an alkali or alkaline earth. Though the extra trouble, and modification of plant, required by this process may operate against its introduction, there can be but one opinion on the merits of an invention which dispenses with a seriously poisonous product. An improvement in the same direction, by the recovery of the arsenic from the waste products of this manufacture, converting it at the same time into a source of profit, is to separate the rosaniline base by means of ammonia, by which the arsenious and arsenic acids contained in the " melt " are converted into arsenite and arseniate of ammonia, both of which are soluble; from these salts, it is proposed to expel the ammonia by heat, and collect it for use over again, obtaining the arsenic in a form ready for reconversion into arsenic acid. The objectionable feature in this is the handling of a readily soluble poisonous material. Toluidinc, or Coupier's Reds. Coupier prepares his reds from (1) pure aniline and pure nitro- 664 COAL-TAR PRODUCTS. totuol ; (2) ordinary commercial aniline and ordinary nitro-benzol ; (3) nitre-toluol and toluidine, or nitro-xylol and xylidine ; using iron and hydrochloric acid iu each case. The products from the first two yield reds identical with ordinary rosaniline; to the last, he gives the name "rosa- toluidine," " toluidine red," or " xylidine red." The apparatus and procedure may be as for rosaniline. Erythrobenzine. Laurent and Casthelaz gave this name to a red colouring matter obtained from nitro-benzol, iron filings, and hydrochloric acid, no aniline being added, although in the reaction it may be produced ; it agrees with rosaniline, with which it is probably identical. Equal parts by weight nitro-benzol and aniline are gradually heated together in an enamelled iron vessel to about 200 (392 F.) ; the heat is continued until the mass becomes pasty, and will solidify, on cooling, to a brittle body resembling crude rosaniline. It is powdered, boiled in water with carbonate of soda to precipitate the colouring matter, and further treated as for purifying rosaniline. This yields a fine red colouring matter, and, as regards the aniline used, is equal in yield to the arsenic acid method. Nitro-toluol and aniline give a colour approaching that of rosaniline; toluidine and nitro-toluol give a red with a decided violet shade. The reds obtained in this way are better adapted for confectionery, colouring liquids, &c., than " rubine," which is made with nitrate of mercury instead of arsenic, and has been largely used for the above purposes. Xylidine Red. Hofmann's xylidiue red is obtained by heating pure xylidine and pure aniline with an oxydant capable of forming rosaniline ; it gives a splendid crimson. It is manufactured and purified as rosaniline (q. v.). Kosaniline and the bases formed in its manufacture are capable of combining with the ethyl and methyl radicals, and from some of them important colouring matters are obtained. See Hofmann's Violet, &c. Tannate of rosaniline is formed as a bright red precipitate, by adding a cold and dilute solu- tion of a salt of rosaniline to a solution of tannic acid ; from warm ami concentrated solutions, a brownish-red brittle mass is produced. By dissolving in alcohol or wood-spirit, it dyes yellowish or orange-red tints. Treated with nitric or hydrochloric acid, it yields a colouring matter passing gradually from violet to blue; by regulating the supply of acid, any desired tint may be obtaimd. It is purified by washing with water, and dissolved in wood-spirit ; its solution diluted with water can be used for dyeing. BLUE COLOURING MATTERS. PHENYL-BOSANILINES. When a rosaniline salt is heated with aniline, hydrogen is replaced by phenyl, and ammonia is given oif, producing monophenyl-, dipheuyl-, and triphenyl-rosaniline ; the salts of the first have a reddish-violet colour ; those of the second, bluish-violet; and those of the third, a pure blue colour, and are known as "candle blue" or " night blue," since their colour is unaltered by artificial light. For the manufacture of aniline blue, the purer the aniline itself, the better will be the colour of the dye produced. The aniline which passes over in the preparation of magenta is generally used for the better kinds of blue, on account of its freedom from the higher homologue bases. Commercial anilines may be fractiouized, and the product coming over at 182-185 (360-365 F.), may be retained for the preparation of the finest blues. These blues are more readily formed when weak organic acids, such as acetic, benzoic, &c., are present ; in their dyeing qualities, much is gained by selecting an aniline of low boiling-point. The proportions of the ingredients vary ; but, as a rule, free aniline is used in large excess. On the Con- tinent, they are prepared in a series of enamelled cast-iron pots, heated in an oil bath over a furnace. The covers are secured by clamps, and supplied with a small opening for withdrawing samples, and a bent tube for leading away vapours to a condenser. Sometimes these tubes are inclined so that the condensed vapours are returned. If the heating is carefully conducted, the volatilized aniline should be trifling. Each pot is provided with an agitator, and has a capacity of about 20 lit. When starting, they are half-filled with the materials, and the covers with their appendages are fitted on, and secured. The covers, tubes, and stirrers are best arranged so that they hoist out together when the pots are opened. A thermometer is placed in the oil bath. A charge may be about 5 kilo, rosaniline salt (acetate, or hydrochlorate), and 10 kilo, aniline ; the temperature of the bath should be kept between 190 (374 F.) max., and 165 (329 F.) min. ; the aniline must not boil. The operation lasts about two hours. The free aniline is recovered by distilling with a current of steam, or removed by means of an acid, or the colouring matter is taken up by alcohol or wood- spirit. In this country, a small magenta-still is used instead of the series of pots. By the subsequent purification of the crude product, the following colours are obtained : Direct Blue. This is the crude colour deprived of the free aniline by a current of steam, or by washing with weak hydrochloric acid, in enamelled iron pans ; the acid poured off one is added to the next, and so on. The aniline is recovered by distillation with lime. Purified Blue. The product in the still is liquefied with wood-spirit, and allowed to trickle into dilute hydrochloric acid. The free bases are taken up, and the colouring matter falls to the bottom ; it is collected on flannel trays, and well washed with acidulated boiling water. BLUES. 665 Night Blue. So called from the absence of violet when viewed by gas or candle light. The crude product is well washed witli wood-spirit, and sometimes boiled after being well divided. It is easier and cheaper in all cases to work upon the previously purified product for the next purifi- cation. Percolation with alcohol or wood-naphtha will purify the ''direct blue" to any required egree, after the heavy anilines have been removed by hydrochloric acid. By varying the proportion of materials and further purifying, the following different qualities of these blues are obtained : B Blue. This blue is obtained by heating for two hours, at 180 (356 F.), a mixture of 2000 grms. pure rosaniline, 3000 grms. aniline ; distilling at 182-185 (360-365 F.) ; and adding 270 grms. glacial acetic, or benzoic, acid. The products from benzoic acid are always more tinted with green than those from acetic acid ; the former are used for silk, the latter for wool. The colour may be made purer by pouring it gently into an enamelled iron pot containing 10 kilo, hydrochloric acid, with brisk and continuous stirring. The precipitate is filtered, and well washed with boiling water acidulated with hydrochloric acid, till it is reduced entirely to powder ; the yield is about 3500 grms. BB Blue. This is produced from pure rosaniline, 2000 grms.; pure aniline, 5000 grms.; benzoic, or glacial acetic, acid, 270 grms. , treated as above. The crude product is thus purified : the boiling mass is turned into an enamelled iron pot, and cooled by being placed in water ; 7-8 kilo, concentrated alcohol are added, and the mixture is stirred till well incorporated; the vessel is heated in a salt-water bath till the alcohol begins to boil ; it is then allowed to cool a little, and stirred, adding 10-12 kilo, strong hydrochloric acid ,- the mass becomes warm from the formation of hydrochlorate of aniline, and at the same time the pure blue separates. To obtain a product of constant colour, the filtering should always be made at the same temperature 45-50 (113-122 F.); the blue is washed with plenty of water, and dried. The product should be about 1320 grms. This blue can also be made from B, by treating one part of the latter with 1J part strong alcohol, and 5 parts rectified benzol, introducing the whole into an apparatus supplied with an agitator and cohobator, and boiling for one hour. BBB, and BBBB Blues. These are prepared by a further purification of BB, 1 kilo, of which is boiled with agitation for two hours with 3G kilo, strong alcohol ; 2 kilo, of an alcoholic solution of soda, containing 20 per cent, alkali, are poured in. when the soda sets the base free. The alcoholic solution is filtered, when a certain quantity of inferior blue is left in the filter. With the alcohol solution still warm, 280 grms. concentrated hydrochloric acid are well mixed ; by leaving the whole to settle for about two hours, BBB is deposited in a crystalline form ; this is filtered, pressed, and when dry, should yield 600-G90 grms. By repeating this operation on the same product, BBBB is obtained. From the mother-liquor from which BBB has been precipitated, a further quantity of an inferior blue can be obtained. A better plan is to dissolve 1 kilo, BB in a mixture of 1 kilo, alcohol, and 2 kilo, aniline, stirring till blended, pouring the whole into 25 kilo, alcohol, and heating till the alcohol boils ; finally adding an alcoholic solution of soda, and filtering. This gives much less insoluble matter. To the filtrate is added a little excess of hydrochloric acid, when a superior blue is thrown down; at the end of forty-eight hours it is filtered off, pressed, washed several times with boiling acidu- lated water, and dried. It yields about 800 grms. BBB Nicholson's Blue. Triphenyl-rosaniline-sulphonic acid is obtained by dissolving triphenyl-rosani- line in concentrated sulphuric acid, and adding water to the solution ; a dark blue mass is formed which dries up into grains, having a beautiful metallic lustre. Its sodium salt is " Nicholson's " or "Alkali" blue, a dark-grey amorphous mass, dissolving in water with a fine blue colour. By the further action of sulphuric acid, other sulphonic acids are formed, and occur, as sodium salts, in several soluble aniline blues. The ammonium salt is Nicholson's ordinary " soluble " blue. To prepare Nicholson's blue, " Blue de Lyons," or " Azaline," is boiled in water containing about 4 oz. sulphuric acid to 1 gall, water ; when the soluble matter is nearly all taken up, the insoluble residue is dried, and reduced to powder, and about lour times its weight of sulphuric acid (sp. gr. 1-845) is added to it ; the temperature is raised to about 149 (300 F.), the mixture is stirred till solution is complete, and is kept at this temperature till a sample is entirely dis- solved in water. If the temperature be raised too high, sulphurous acid will be evolved, to the destruction of the dye. Its dilute acid solution is used for dyeing and printing in the ordinary way. By the use of an excess of lime or alkali to neutralize the acid, it is thrown down, and a colourless solution is obtained, which, on addition of a weak (organic) acid, develops a soluble blue. By varying the proportion of sulphuric acid, the heating may be curtailed or prolonged : it is best to work on small quantities, so as to limit the generation of heat The tints are improved by increasing the acid ; but when very large quantities are used, the colours are more fugitive ; the proportions giving the most durable colours are those required to produce mono- and di-phenyl- 666 COAL-TAB PKODUCTS. rosaniline sulphonic acids, and heating to 100 (212 F.) ; these colours, however, are not so soluble as when the heat has been raised to 149 (300 F.). Anhydrous sulphuric acid may be used instead of concentrated acid, without heating. Caro (1877, No. 3731) converts the crude magenta bases into sulpho acids in the same way. The advantage of these dyes is that they can be used in presence of acids or acid mordants. Diphenylamine Blue. Girard and De Laire (1866, No. 2686) prepare a blue from diphenylamine and sesquichloride of carbon, by heating a mixture of 2 parts of the former and 3 of the latter, for five to six hours, in an enamelled iron vessel, to 170-190 (338-374 F.). The apparatus used is the same as for making diphenylamine. Besides diphenylamine, ditoluylamine, phenyl-toluylamine and diphenyl-amyl-arnine may be used. These may also be treated with oxalic acid for the same purpose. The development of colour is watched by drawing samples ; it is complete when a copper red is produced, and the cooled mass becomes hard and brittle, and dissolves in alcohol with an intense blue. It is purified by dissolving at 100 (212 F.) in double its weight of aniline ; the solution is thrown into a large quantity of benzol, kept well agitated ; the vessel is kept cool, so as to avoid loss of benzol. The blue is precipitated as a very fine powder, collected on a canvas strainer to drain, and well pressed ; it is repurified in the same way without being pressed, and is washed on the strainer with benzol. It may be further purified by dissolving in boiling aniline; precipitated by hydrochloric acid, the aniline salt is washed out with boiling water. The free base is obtained by caustic soda, and purified by solution in alcohol. The separation of blue from violet colouring matter is effected by dissolving in ten times its wei-ht of oil of vitriol heated to 30-60 (86-140 F.). Water is added to precipitate the blue, whilst the violet remains in solution; it is thrown on to an asbestos filter, and washed with dilute acid, then water; it is drained and pressed, and if required with greater purity, the previous process is carried out. Toluidine Blue, or Tri-toluyl-rosaniline. The composition of this blue is analogous to that of tri- phenyl-rosaniline, and its mode of preparation is similar. Equal parts of rosaniline and crystal- lized toluidine are heated for five or six hours to 150-174 (302-346 F.). Its extraction and purification may be effected with hydrochloric acid and water. It dissolves in alcohol with a beau- tiful blue colour. Bleu de Coupier, or Triphenyl-roso-toluidine. Toluidine red heated with aniline yields a blue colour- ing matter, known by this name. It is prepared in the same way as Coupier 's reds (q. v.), by substituting his toluidine red for rosaniline. Bleu de Paris. This is obtained from methyl-anilines and anhydrous bichloride of tin ; it is a triphenyl-rosaniline. (See Violet de Paris.) Aldehyde Blue. This colouring matter is a valuable source of green, and although its merit as a blue does not entitle it to the notice of the dyer, its preparation must be noticed here. A solution of 20 grins, rosaniline, in 280 cc. ordinary hydrochloric acid, is diluted with an equal volume of water, and mixed with 100 cc. crude aldehyde. After twenty-four hours, the blue is precipitated by caustic soda in excess, collected on a filter, washed, purified by solution in alcohol, and dried. A yellow resinous matter is removed by carbon bisulphide. Its solution iii wood-spirit dyes well, but not deeply. (See Aldehyde Green.) Bleu de Mulhouse. This product, having the colour of aminoniuret of copper, is obtained by boiling 50 grms. bleached shellac, and 18 grms. soda crystals, in 1 lit. water, and adding 50 cc. solution of magenta (1 part magenta in 4 parts water, and 4 parts alcohol), boiling for one hour, and adding water and spirit as they boil away. Azurine. Blumer Zweifel makes this colouring matter as follows : 100 grms. starch is boiled in 1 lit. water, and whilst boiling, 4 grms. chlorate potash, 3-4 grins, sulphate iron, and 10 grms. sal- ammoniac, are added. When the mass has cooled and set, 60 grms. of a salt of aniline is added, and well mixed and dissolved. Its tints are altered by varying the proportions. Tripheuyl-Mauvaniline. This base is converted into ethyl, methyl, and phenyl compounds in the same way as rosaniline ; it is soluble in alcohol, and its salts yield splendid blue colouring matters. (See Triphenyl-rosaniline, Kosaniline residues, and Mauvaniline.) Mauveine, Mauve, Aniline-blue, or Perkm's Violet. C 2r H 24 N 4 . The production of this interesting colouring matter depends upon the action of an oxidizing agent on aniline, or a salt of aniline, such as the sulphate or chloride. A cold saturated solution of sulphate aniline is mixed with an equal quantity of a cold saturated solution of bichromate potash, and allowed to stand for 10-12 hours. The quantity of potash is such as to produce, with the sulphuric acid from the aniline salt, the neutral sulphate. The mixture is thrown on to a filter, and washed until the potash-salt is all removed ; the residue is dried at 100 (212 F.). The adhering resinous matter is washed away with coal-tar naphtha or petroleum, and when the naphtha has evaporated, the washed mass is dissolved in wood- naphtha or methylated spirit. Instead of washing away the resinous matter, it is more economical to treat the crude mass with slightly dilute wood-naphtha or methylated-spirit ; as the resinoua VIOLETS. 667 impurities are but slightly taken up, the larger proportion of the spirit is recovered by distillation, and an aqueous solution of the colouring matter remains; by evaporation, it can be obtained either in a dry crystalline state, or in paste. Caustic potash, a.lded to a solution of the sulphate, precipi- tates the mauveine, which is almost insoluble in water, but dissolves readily in alcohol, yielding a bluish-purple colour. It ia a powerful base, combining with acids to form well-defined salts, which have a fine metallic lustre; it expels ammonia from its combinations. When the base is heated with aniline, ammonia is given on', and a blue colouring matter is formed. It has been proposed by Perkin to obtain an ethyl compound, by heating equal parts of mauveine and iodide ethyl together, for the general carrying out of this (see Hofmann's violet, &c.) ; it was largely used a short time ago, but the replacement of iodine by less costly methods of intro- ducing the alcohol radicals must eventually restrict its use. It dyes deeper and finer shades of mauve. By oxidizing a hot solution of mauve with sulphuric acid and manganic oxide, a beautiful red colouring matter is produced ; it is very soluble in water, and forms crystals having a fine beetle- green lustre. In concentrated sulphuric acid, it dissolves with a dark green colour, which, on adding water in small quantities, changes into bluish green, pure blue, violet, purple, and at last into pure red. This was originally called " safranine " ; but the colouring matter now met with in commerce under that name is obtained from a very different source. PHEXYL VIOLETS. In the purification of di-phenyl-rosaniline blues, blue and violet colouring matters are obtained. The blue obtained by heating equal parts of rosaniline and aniline for four hours at 149-160 (300-320 F.) is, whilst being boiled with dilute muriatic acid (1 acid to 9 water), freed from the unaltered bases, which contain the violet. This violet is not pure, but, according to the purification, are obtained violet-red or dahlia, and violet-blue or panne ; between these are found all shades of violet. By even the most careful manipulation, it is not always possible to get the same shades, consequently the exact shades required are obtained by mixing the blues and reds. Mono-phenyl-rosaniline (red-violet). Rectified aniline, 14 kilo., is gradually added to acetate of rosauiline, dried at 100 (212 F.), 10 kilo., in a still, so as to collect the aniline which comes off. The rosaniline salt is first heated gently by itself; the cohobation with aniline is continued for one hour, when the heat is raised to 190 (374 F.). Samples of the product are drawn out every few minutes, so as to watch the production of colour, which should be a very red violet. The mixture is allowed to cool a little, when it is softened wiih a little benzol, which removes the aniline, and a brown colouring matter, whilst the rosaniliue and other products are precipitated. The precipitate is thrown on a strainer, dried, and dissolved in hydrochloric acid ; from this, the violet is thrown down by the addition of a large quantity of water, well washed, and dried. JJi-phenyl-rosaniline (blue-violet). Rosaniline salt, 10 kilo., and aniline, 20 kilo., are treated, as above, for at least one and a half to two hours. Acetate rosaniline is sometimes used. The product is examined from time to time, and when the tint is obtained, the vessel is removed or allowed to cool. Alcohol, 4-5 lit., are added, to soften it, and the whole is poured into a large quantity of ale hoi, to which hydrochloric acid is added. The colouring matter is precipitated by adding a saturated solution of common salt, and is well washed on a flannel strainer with acidulated water. Ethyl and methyl rosanilines. Ethyl and methyl violets are now largely made from methyl-aniline (see Violet de Paris), so that the costly production of Hofmann's violets from iodides of ethyl or methyl has become of interest principally as a source of other important colours. The modus operandi (No. 1291, 1863) is as follows : One part by weight of rosaniline, 2 parts by weight of iodide of ethyl, and about 2 parts of strong methylated spirit are heated together in a suitable vessel, to a temperature of 138 (212 F.), for three to four hours, or until the whole of the rosaniline is converted into the new colouring matter The syrupy mass obtained on cooling is dissolved in methylated spirit or alcohol, and may be used at once for dyeing and printing. The iodine is thus recovered : The product either before or after dissolving in spirit is boiled with an alkali, by which the base is precipitated, whilst iodide potassium remains in solution. The base is washed and dissolved, together with an acid (as hydrochloric), in alcohol, or in place of hydrochloric acid and alcohol, acetic acid and water; these solutions can be employed for dyeing and printing, giving to silk and wool beautiful violet, blue- violet, and red-violet tints. Instead of iodide of ethyl, the iodides and bromides of methyl, amyl, propryl, and capryl may be employed, but not so conveniently, as they are more expensive. Three shades of violet, viz. R, reddish violet ; B, blue- violet ; and BB, a light- violet, were formerly supplied in this material. For red-violet. Ten kilo, of rosaniline, 100 lit. alcohol, 8 kilo, iodide of ethyl or methyl, and 10 kilo, caustic soda or potash ; the mixture is heated for two hours at 115-130 (239-266 F.). For blue-violet. Ten kilo of rosaniline, 100 lit. alcohol, 5 kilo, iodide methyl, 5 kilo, iodide of ethyl, and 13 kilo, caustic soda or potash. For light-violet. Ten kilo, of rosaniline, 20 kilo, iodide of methyl, 100 lit. ethylic alcohol, and 10 kilo, caustic potash. The solutions of iodide ethyl and methyl should be added very gradually, as also the caustic- solutions. Other intermediate shades may be obtained by varying the propor- tions. Iodide of methyl gives a more decided blue shade than the iodide of ethyl, and the colouring 668 COAL-TAR PRODUCTS. matter is also more soluble in water than the iodide of ethyl product. The products are the iodohydrate of ethyl-rosaniline or of methyl-rosaniline ; both are purified in the same way. The salts of both bases are soluble in alcohol, wood-naphtha, acetic and mineral acids ; the colours obtained from the salts of trimethyl-rosuniline are much brighter than those from suits of the other base, whilst suits which contain both bases are still more beautiful as dyes. Mauvaniline (see Rosaniline residues). The precipitates containing rosaniline and mauvaniline are submitted to the action of hydrochloric acid, salt, &c., so as to separate them as completely as possible; the mauvaniline is washed with benzol, and digested in a cohobator with alcoholic potash, by which the free base is obtained. It is washed with water, and when dissolved in acid, dyes magni- ficent mauve shades. According to Girard and De Laire, 12 per cent, of this is obtained from rosaniline refuse. Triphenyl-mauvaniline yields salts soluble in alcohol ; they have a beautiful blue colour. Ethyl-mauvaniline. By treating mauvaniline with iodide of ethyl, Girard and De Laire obtain a violet colour, which is bluer according as the iodide is in greater proportion to the mauvaniline salt. It may be made in the same way as Hofmann's violet (q. v.), with 1 kilo, mauvaniline, 10 lit. wood-spirit, 3 kilo, iodide ethyl (or methyl), and 1 kilo, potash or soda. Violet de Paris. Poirrier and Chappat's violets are obtained from methyl-anilines ; according to the predominance of blue or violet tints, reddish blues, blues, and pure violets are produced. It is highly probable that for blues and violets, this is destined to become a very important source. To obtain violet, violet-red, and violet-blue, from methylic, methyl-ethylic, and methyl-amylic anilines, 1 part methyl or dimethyl-aniline, and 5-6 parts anhydrous bichloride tin are mixed in a still, heated up to 100 (212 F.) for some hours, and well stirred until hard ; the mass is treated with caustic alkali, washed and filtered ; the precipitate is boiled in water, and neutralized ; from this solution, filtered when cool, common salt throws down a green precipitate, which is collected on a filter, and may be further purified by crystallizing from solution in alcohol; its solution in boiling water dyes a magnificent violet. If the heating has been sufficient, the mixture is found as a black tarry mass. Instead of bichloride tin and bichloride mercury, arsenic acid may be used ; or if 100-150 parts chlorate potash, 100 parts methyl-aniline, and 100 parts water are used, the reaction which follows from the splitting up of the liberated chloric acid yields the colour. Chloride iodine diffused in 5-10 parts of water may also be used ; or a mixture of 80 parts chlorate potash, 20 parts iodine, and 100 parts methyl-aniline. lodates, bromates, and iodic and bromic acids react on methyl-aniline salts with the same development of colouring matter. Bichloride of mercury alone develops very little colour ; terchloride benzol and terchlorophenic acid develop a violet, at 150 (302 F.). Ked violets are obtained by employing methyl-aniline and bluer violets, when dimethyl-aniline, or higher methylic homologues, are used. After purification, these violets are all soluble in water, alcohol, and acetic acid, and are used for dyeing and printing as other aniline dyes. Brooman's improvements (1866, No. 3195) consist in treating chlorides of methyl-anilines with nitrate or chloride of copper for violets, which yield bluer shades according as the heating is prolonged. The oxidation products from these violets give, with chloride-benzyl, still bluer shades of violet. The methyl and ethyl violets met with in commerce are E. B. BB., to 6B. Bardy obtains violets from methyl-diphenyl- amine (q. v.), which are also capable of yielding mixtures of blue and violet. Girard and De Laire's violet from methyl-benzyl-phenyl-amine may be thus produced : Methyl-benzyl-diphenyl-amine, 15 Ib. ; chlorate potash, 2 Ib. ; water, 40 Ib. ; and non-calcareous sand, 100 Ib., are well mixed, placed in a cohobating apparatus, and heated; a solution of sulphate of copper (5 Ib. to 15 Ib. water) is added during the heating, in small portions at a time. The temperature is kept for twenty-four to thirty hours at 50-80 (122-176 F.); when the reaction is complete, the mixture is carefully neutralized with caustic soda or potash, or lime water, and the unaltered portions of the bases are removed by distilling with a jet of steam. The mass is then treated with hydrochloric acid in slight excess, and the colouring matter is removed by hot water, and thrown down with common salt ; it is then converted into a base by soda or potash ; this is well washed, and again converted into hydrochlorate or acutate. These salts are soluble in water, and dye blue-violet. The colours obtained from the corresponding compounds may be produced in the same way by substituting the alkaloid or its salt ; benzyl-diphenyl-amine gives a bluish green or greenish blue; benzyl-phenyl-toluyl-amine, orange; benzyl-ditoluyl-amine, brown or chestnut ; methyl-diphenyl-amine, blue. This same process is, according to Bolley and Kopp, employed by Poirrier for the manufacture of violets from methyl and di-methyl-anilines (q. v. ; also violet de Paris). Violanilim (see Rosaniline residues). This base forms salts soluble in alcohol ; the solutions dye silk and wool a rusty black with a shade of violet. GREENS. The green colouring matters obtained from coal-tar are produced by certain reactions on other aniline or toluidine colours. Aldehyde, or Usebc's, Green. Sulphate rosauiline, 150 grms,, are dissolved in a cooled mixture of GEE ENS. 669 3 kilo, oil of vitriol and 1 kilo, water ; 225 grms. crude aldehyde are gently added, with continued stirring; the whole is heated in a salt-water bath, till a drop let fall into dilute acid appears green ; 450 grms. hyposulphite soda, dissolved in 30 lit. boiling water, are added very gradually, and the whole is boiled for a few minutes ; the green liquid is filtered from the sulphur which separates from the hyposulphite, and is ready for use. Lucius' method of obtaining aldehyde green differs from the foregoing mainly in the use of sulphuretted hydrogen, and an alkaline sulphite instead of hyposulphite soda ; 1 Ib. sulphate rosaniline is dissolved in a mixture of 2 Ib. sulphuric acid with 2-4 Ib. water, adding 4 Ib. aldehyde, and heating to about 50 (122 F.), till a sample dissolved in about fifty times its weight of alcohol yields a greenish-blue solution ; to this is added 300-500 Ib. saturated aqueous solution sulphur- etted hydrogen, gradually increasing the heat to 90-100 (194-212 F.), adding 10 Ib. satu- rated solution sulphurous aoid, and filtering the liquid from the blue colouring matter which has been precipitated. The green remains in solution, a,nd is obtained in the solid form. Aldehyde green, when kept for any length of time, loses much of its beauty, and may even become useless ; on this account, it is best prepared as wanted. It is sold in two forms : dry, and in paste ; in the dry state, it is an amorphous powder, insoluble in water, readily soluble in a mixture of dilute sulphuric acid and alcohol, and sparingly soluble in alcohol alone. To produce the powder, it is precipitated from solution by neutralizing with carbonate soda, or by adding common salt; it is washed by decantation, and finally dried at or below 100 (212 F.). As the paste is more readily soluble than the powder, and appears to keep better and longer, it is the pre- ferable form, especially as the difficulty of drying is then dispensed with. Toluidine Green may be obtained by treating Coupler's red, or rosotoluidine, with aldehyde in the same way. Gas Green. This colour is so called from its appearing green in artificial light. Luthringer gave this name to a green obtained by mixing a yellow with blue (see Yellows). Different shades of green are obtained in printing and dyeing, by superposing one colour on the other. ffofmann's Green. This colour is obtained from Hofmann's violet, either by direct treatment, or by reactions in which ethyl-rosaniline appears as an intermediate product. One part acetate rosani- line, 2 parts pure iodide methyl, and 2 parts methylic alcohol, are placed in an enamelled digester withstanding a pressure of 400 Ib. a sq. in., and heated to 100 (212 F.) for twelve hours in a water bath. The green and violet colours formed dissolve in the methylic alcohol ; when the digester is opened, the volatile products escape ; a gentle heat is applied to drive off the free methylic and methylic-acetic ethers, leaving the residue as a paste, which, when thrown into boiling water, gives up the green colour ; the small quantity of violet dissolved is removed by addi- tion of common salt and a little carbonate soda. The solution is filtered through sand or asbestos, and precipitated by adding cold saturated solution picric acid. In commerce, it is met with in paste as picrate, which is readily soluble in alcohol. The soluble green, manufactured by Girard and De Laire, is a double zinc salt, produced by adding to a solution of the colour, sulphate, chloride or acetate of zinc ; it is soluble in water, and in addition to the saving of alcohol as a solvent, it dyes fibres with a purer green than does the picrate. Pure crystals are obtained by dissolving in boiling, absolute alcohol, and precipitating by anhydrous ether ; the precipitate is dissolved in boiling alcohol, which, on cooling, deposits crystals. This green has been greatly replaced by methylaniline green (q. v.). Paris Green. Under this name, Poirrier, Bardy and Lauth, prepare a green colour from anilines derived from benzol or toluol, or mixtures of these, by oxidizing with bromine, chlorine, or iodine, or fheir compounds, or with nitric acid, nitrates, arsenic acid, &c. The usual process is as follows ; 100 Ib. aniline, 80 Ib. chlorate potash, and 20 Ib. iodine, are heated to 100 (212 F.) ; in order to subdivide the mass, sand may be added, when the reaction requires less heat ; after a few hours, when the mass has become hard and brittle, it is first treated with boiling water, and afterwards with a boiling solution of potash in alcohol. By this means, the product is obtained in a tolerably pure basic condition. This base is then treated with strong acetic acid to convert it into a neutral salt ; in this state, the green colour, dissolved in alcohol, can be used for dyeing and printing. It may be further purified by n dissolving in alcohol, filtering, precipitating by soda, treating again with glacial acetic acid, and redissolving in alcohol. Methylaniline Green. This is obtained from Poirrier's methylamine violet. The violet is first precipitated by chloride zinc and subsequent saturation with carbonate soda; the filtrate is concen- trated, and, on cooling, deposits crystals of a double compound of the aniline green and zinc. ANILINE BROWNS. The processes for the production of these colours depend upon the reducing action of certain bodies upon magenta or rosaniline, or their mother-liquors, with or without aniline, or by making a salt of aniline react on magenta at a high temperature. Levinstein heats 1 part rosaniline with 1 part formic acid, to 180-200 (356-392 F.), when the mixture appears dark brown ; dissolved in alcohol or wood-spirit, it becomes scarlet ; by heating to 258 (496 F.), and then dissolving as above, it becomes red-orange ; and when heated 670 COAL-TAB PRODUCTS. to about 265 (510 F.), and dissolved as above, yellow-orange is produced. In order to prepare a brown, wnen the mixture has become scarlet-red, it is left to cool, and is then mixed with 3 parts aniline ; the whole is heated at 189-210 (356-410 F.), and the excess of aniline is separated. Sopp obtains a brown from rosaniline residues bj oxidation. Girard and De Laire obtain brown matter from rosaniline residues (q. v.)- The precipitate obtained by treating the residues with soda in excess consists principallv of chrysotoluidine. It is dissolved in clear lime water, boiled three or four hours, filtered into dilute hydrochloric acid ; on cooling, a salt crystallizes out, which is met with in commerce as " yellow fuchsine." The residue contains nearly pure chrysotoluidine, the lime is taken up by boiling in an iron vessel with hydrochloric acid to exactly neutralize it, the base fuses and rises to the surface ; this is purified by solution and precipitation with carbonate soda, and is converted into sulphate. These substances dye silk .and wool yellow ; with more or less rosaniline it gives orange, deep yellow, and browns; the less purified product is used for dyeing leather, &c. Their " maroon " is prepared as follows : 4 parts anhydrous aniline hydrochlorate are fused, and 1 part dry aniline violet or blue is added. When entirely dissolved, the temperature is raised to 240 (464 F.), and maintained till the colour suddenly becomes brown. The operation lasts one to two hours, and is complete when yellow vapours condense on the sides of the apparatus. This brown is soluble in water, alcohol, and acids, and may be used without further treatment ; it is precipitated from its solutions by alkalies and neutral salts. It dyes beautiful shades of brown on silk, leather, and wool. Instead of aniline dye, material for producing the dye may be substituted, e. g. arseniate aniline may be treated with hydrochlorate aniline. By oxidation, brown shades are produced, n.ore or less orange, according to the degree of oxidation (see Leucaniline). Durand's brown is produced in the same way as some aniline blacks, by oxidizing an impure leucaniline in the presence of copper salts. The cheapest and best source is the article known as cerise (q. v.). This is boiled with zinc and dilute sulphuric acid; the solution, when saturated with common salt, deposits a brownish colouring matter, which, dissolved in dilute acids, alcohol, &c., dye? yellowish shades, nankin, tan, and browns. Siberg obtains a brown from the impure matter precipitated from the mother-liquors <>f magenta ; 1 part hydruchlorate aniline is melted, and to it is added part of the colour residues ; the whole is heated on a sand bath until the brown colour appears. The product is mixed with 2 parts crystallized carbonate soda dissolved in 25 parts water, and well stirred ; the liquid is left to settle, and the colour is washed several times. When dry, it is brownish black. For use, 1 part of this resinous substance is dissolved in 9 parts alcohol, and the solution is mixed with 13 parts water. Manchester Brown. Robert, Dale, and Co., of Manchester, manufacture a brown known by this name. A cold, weak, neutral solution of phenylene hydrochloride is gently added to a neutral solution of a nitrite ; a deep-red crystalline mass separates out ; this is first washed with water, and is afterwards treated with concentrated hydrochloric acid, in which it dissolves, and afterwards separates out as a tarry mass. This compound of colour and hydrochloric acid is dissolved in water, and mixed with a solution of ammonia, which precipitates the colour as a brown crystalline mass. Its aqueous solution dyes wool and silk without a mordant ; the colour is orange or yellow- orange ; but, in contact with the atmosphere, or on rinsing in dilute hydrochloric acid, it passes to a deep reddish brown. The acetic acid solution of the brown colour also dyes reddish brown if somewhat concentrated, and yellowishbrown if dilute. ANILINE YELLOWS. In 1864, Simpson, Maule, and Nicholson offered a yellow dye stuff under the name of " Aniline Yellow," which is an oxalate of the product obtained by the action of nitrous acid on aniline (see Amido-azo-benzol). Aniline is dissolved in three times its weight of alcohol, and nitrous acid is passed into the solution until the liquid becomes deep red; this is afterwards mixed with a large excess of slightly dilute hydrochloric acid, to separate the colouring matter ; the crystilline product is filtered, washed with very weak alcohol, and boiled several times in water ; the solution is mixed with ammonia, and the product is purified by recrystallization ; its solution in alcohol is used for dyeing. By heating the acid, a shade between garnet-red and brown is produced. SchifTs yellow is met with in commerce as a paste; dissolved in weak acids, it dyes a yellow, which is rendered more solid by passing through a solution of carbonate of soda ; 3 parts stannate eoda, 1 nitrate aniline, in 10 of water to which a little carbonate soda is added, are heated to 100 (212 F.) ; a strong reaction sets in ; as soon as acids produce a red coloration, the process is complete. On adding strong hydrochloric acid, the colour is deposited aa a resinous mass. Zinaline. This is obtained by acting with nitrous acid on solutions of rosaniline, Hofmann'a and ordinary violets, Usebe's green, and Girard's aniline brown. Different tints are developed according to the amount of gas passed through, the highest shade being a yellowish red. Evapo- ration in a salt-water bath produces a red powder. Its solution in alcohol with a little ammonia gives, on silk and wool, bright shades of orange. With indigo-dyed goods it gives a green. CAKBOLIC ACID. 671 Sopp's yellow, or jaune de Lyon. (See Cerise). ANILINE BLACKS. These are produced by the action of oxidizing agents on anilines, generally in contact with the fabrics to be dyed, though paste blacks are sent out by some makers. The anilines employed in blacks and greys for calico-printing, &c., generally contain 60-65 per cent, liquid, boiling at 180-185 (356 c -365 F.) pure aniline, 18-22 per cent., boiling at 185-192 (365-377 F.); aniline and toluidine, 8 per cent., boiling at 192-198 (377-388 F.) ; toluidine ; and 4-6 per cent, xylidine, &c. Their sp. gr. should be 2-3J B. ; those of higher sp. gr. may contain nitro-benzol, while in those below 2 there is much toluidine, which injures the black. When fractionized, these anilines should distil almost entirely at 180-190 (356- 374 F.). Coupier's anilines, which distil at 180-185 (356-365 F.), are said to produce the richest blacks. Pseudotoluidine, and the products boiling at 185-192 (365-378 F.), give " blue- blacks." Toluidine, and the products boiling above 192 (378 F.), give rusty blacks ; on this account, they are rejected. The salts of aniline cannot be used indiscriminately for producing blacks ; nearly all the salts with organic acids give very unsatisfactory results, as do even those obtained with mineral acids, if perfectly neutral ; the solution must be acid, and in this way, it is possible partially to regulate the character of the black. The hydrochlorate and disulphate with excess of acid are usually employed. A description of Lightfoot's and similar methods of obtaining aniline blacks belongs more appropriately to the department of the dyer, and will be treated in the article on Dyeing and Calico-Printing. Attempts have been made to prepare a black dye from aniline in the same form as other colours. Coupier proposes to mix 175 parts commercial aniline with an equal quantity nitro-benzol, adding 200 parts hydrochloric acid, 16 parts iron filings, 2 parts copper filings, and heating the whole for six to eight hours at 160-200 :i (320-392 F.) in an enamelled iron pot fitted with a condenser. The operation ia complete when the mass can be drawn into threads. This black is soluble in acids, alcohol, and wood-naphtha ; for use, it is dissolved in sulphuric acid. Lucas' black is a soft, black mass, composed of hydrochlorate aniline and acetate copper. It produces a black of very good tone, and can be obtained at a low price. The black supplied by A. Miiller, of Ziirich, is obtained by dissolving in \ lit. water, chlorate potash, 20 grms. ; sulphate copper, 30 grms. ; chloride ammonium, 16 grms. ; hydrochlorate aniline, 40 grms. The mixture is heated in a salt-water bath at about 30 (86 F.); after a few minutes, it froths and swells up ; if, at the end of some hours, it becomes pasty without turning quite black, the heating is continued. The paste is exposed to the air for some days, washed on a filter till no salts are found in the filtrate, and is removed from the filter as a deep-black paste, containing about 50 per cent, of dry colour. A blue-black is obtained from this, by finally washing with 20 grms. soluble blue in 1 lit. water. These colours are mixed up with much albumen, which is the principal drawback to their use. The dry black, ground up, and mixed with a solution of gum, is said to equal the best Indian-ink. Miiller's black is largely used. ANILINK GREYS. Abel's grey is thus obtained : 2 Ib. aniline, boiling at 188 (370 F.), is mixed with 10 Ib. solution arsenic acid (sp. gr. 1-375), and heated in a water bath till the mixture thickens and rises. The vessel is then withdrawn from the fire, and a little water is poured in, to prevent boiling over. The product is tl.ick and blackish, and is insoluble in water. It is purified by adding 18 qts. water and 2 Ib. hydrochloric acid, boiling for about half an hour, and filtering ; the precipitate is washed with boiling water, and finally with a weak solution of sodic carbonate, so as to neutralize the acid, after which it is dried, and remains as a fine black powder. Its solution is effected in alcohol, to which 10 per cent, sulphuric acid may be added, and will produce many shades of grey by addition of the requisite mordants to the bath. Greys are obtained from weak solutions of some blacks. One is prepared by Casthelaz by mixing 10 parts by weight of Perkin's violet with 11 parts oil of vitriol, and 6 parts aldehyde^ and heating for four to five hours. The colour is precipitated, from its dilute solution, by an alkali, and washed. A recent application of the aniline dyes is for the production of coloured lacquers; the salts used should be as free as possible from water. They are also employed to separate cotton from, woollen rags, the former taking no colour from a dye which produces a pronounced tint in the latter. Carbolic Acid. (See also p. 41.) This compound is now regarded as benzol, one atom of whose hydrogen has been replaced by the radical HO ; its formula is therefore C 6 H S (HO), benzol being C 6 H 6 . When in a pure state, it consists of colourless acicular crystals, and has a sp. gr. of 1-065; Cal vert's " Pure Medicinal" acid fuses at 42 (108 F.) to an oily liquid, and boils at 182 (359 F.). Carbolic acid is one of the most powerful antiseptic and antizymotic agents at present known, and exhibits strong anaesthetic and escharotic properties. In the animal kingdom, it is found in the urine of men horses, and cows ; in the vegetable world, it exists in the castor 672 COAL-TAE PRODUCTS. plant, in the Andromeda Lcschenaultii, a plant growing on the high lands of India, and in the resin of the Zanthorrhcea hastilis ; among minerals, coal seems to be the only one in which it has hitherto been discovered. It may be produced by the action of nitrous acid on aniline, and by the dry distillation of gum benzoin, quinic acid, and chromate of pelosina ; there is besides the ordinary commercial process of extracting it from the oils of coal-tar. Early Methods of Manufacture. So long ago as 1834, carbolic acid was discovered by Runge to be a constituent of coal-tar oil ; and about seven years later, Laurent made further investigations into its properties, and succeeded in separating it. He considered it to be a hydrated oxide of a peculiar compound radical, phenyl, whence he named it hydrated oxide of phenyl. Mansfield, in 1847, and Bobceuf, in 1856, made some improvements in the processes of extraction ; but it was reserved for the late Dr. Grace Calvert and his partners to work out the manufacture, to such perfection as would enable the acid to be produced at a saleable figure on a large scale ; and his firm is now the largest, as it is undoubtedly the first, in this branch of chemical industry. Laurent's method of preparing carbolic acid from coal-tar consisted in submitting the light oils to a fractional distillation, and then treating those products which had distilled over at tempera- tures varying from 160 to 218 (320 to 424 F.) with a concentrated solution of potash, separating the alkaline solution from the hydrocarbons which floated on it, and afterwards neutralizing the alkali by an acid, which last process liberated the carbolic acid from the alkaline solution. Pure carbolic acid was present, however, only in very small proportion. The product was, in fact, a mixture composed chiefly of different liquids, similar in properties and composition to carbolic acid ; and, though Laurent succeeded in obtaining solid carbolic acid, the process devised by him was too expensive to answer on a manufacturing scale, and his mode of operation was too complicated. The modifications suggested by Mansfield, and later by Bobceuf, consisted principally in employing caustic soda instead of potash, and in treating the whole of the light oils, instead of only a special portion of them ; still the result was a highly impure acid, from which it was very difficult to extract the pure a/;id. Commercially, however, their process was a step in the right direction, and was employed by Clift, under Dr. Calvert, in manufacturing some carbolic acid, about thirty years ago. This impure acid was successfully used, by Dr. Calvert, in producing picric acid, in preventing the transformation of tannic acid into gallic acid, in tanning, and in the preservation of subjects for the dissecting-room. In 1859, a demand arose for a purer acid. From experiments instituted by Dr. Calvert, it was found that the best mode of preparation was not by treating light or heavy oils of tar with con- centrated alkalies; but, on the contrary, by treating the impure benzols or naphthas of commerce distillates from the tar oils with weak alkaline solutions. By this means, was produced a blackish fluid, a little heavier than water (sp. gr. I'OGO), and containing 50 per cent, of real carbolic acid, which latter was separated in part by careful distillation. This acid continued in use for colour manufacturing till 1861, when aniline colours of such fineness and brilliancy were produced, that, in order to keep pace with them, it became necessary to still further improve the quality of the carbolic acid. After some trials, white detached crystals of the acid, melting at about 29 (85 F.), were obtained. In 1863, this relative purity was again found to be insufficient, and further efforts to increase it resulted in the production, on a commercial scale, of Laurent's " phenylic alcohol," a substance melting at 35 (95 F.), and boiling at 186 (367 F.). Eepeated attempts to draw the attention of the medical profession to the remarkable therapeutic qualities of this acid were then made ; but the tarry and sulphuretted odours which it still possessed were serious obstacles in the way of its application. Dr. Calvert soon succeeded, however, in removing these objectionable features, and was able, in 1864, to manufacture an acid quite free from sulphuretted smell. Still he did not stop his researches ; but, two years later, discovered a process which enabled him to show an acid completely deprived of all disagreeable odour and tarry flavour, and as pure, though extracted from tar, as if it had been produced by the help of the reactions noticed by Wurtz and Kelcule, based upon the direct transformation of benzol into carbolic acid, or by the well- known changes by which it may be obtained from salicylic or benzoic acids. This new phenylic alcohol, or carbolic acid, was, however, in some respects distinguished from Laurent's. Thus, it was soluble in 12J parts of water instead of 33 ; was fusible at 42 (108 F.), instead of at 35 (95 F.) ; and boiled at 182 (360 F.), instead of at 187 (368 F.). Nevertheless it gave, like Laurent's, the blue colour described by Berthelot as being produced on mixing ammonia with it and adding a email quantity of hypochlorite to the solution, the same effect being produced by exposing to hydrochloric acid vapours a chip of deal that has been soaked in this pure carbolic acid. It was supposed that, as Laurent's acid had constant boiling and crystallization points, it was a pure and definite substance ; but the production of this pure acid proved it to be nothing of the kind, Laurent's article being only a combination of pure carbolic acid with a liquid homologue ; for when a certain proportion of water is added to Laurent's acid, and the mixture is exposed to a temperature of 4 (39 F.), it deposits large octahedrons of a crystalline substance, which is a hydrate of carbolic or phenylic alcohol, that is to say, carbolic acid combined with an equivalent of water of CAEBOLIC ACID. 673 crystallization. This fact is highly interesting from a chemico-theorefical point of view, for it exhibits the only example known of an alcohol which, combining with water, forms a crystalline hydrate. By removing from this hydrate the equivalent of water, as well as the traces of sulphuretted compounds, and coal-tar bases, which it contains, carbolic or phenic acid is obtained in its purest state. Present Method of Manufacture. To procure crude carbolic acid, the coal-tar is distilled in a still much resembling in all respects that used for the distillation of the acid (to be shown presently), only of about twenty times as great a capacity. The distillate from the coal-tar is collected in various portions, as already indicated, the largest proportion of the carbolic acid being generally present in the " light oils," a black spirit having a powerful, unpleasant, tarry odour. This tar oil is mixed with a caustic soda solution at 12 :> Tw., made from cream caustic soda, and is put into a barrel- shaped boiler fitted inside with arms, which are made to revolve on a spindle, and thus thoroughly agitate the mix- ture. The result of this process is that the caustic soda dissolves out the whole of the carbolic acid, while the separated and undissolved oily matters, known as creosote oil, float on the surface of the solution when it is allowed to settle. The alkaline solution is then run off from the supernatant oils, and is treated with brown oil of vitriol (sulphuric acid at about 140-150 Tw.), in just sufficient amount to completely neutralize the soda, without being in excess. This acid forms a salt with the soda sulphate of soda which sinks, while the carbolic acid rises to the surface. Generally, the sulphate of soda is allowed to settle out twice, so as to leave the carbolic acid as free from it as possible. At this stage, it is known as "crude" carbolic acid, and, though considerably purified, it still retains a deep black colour, and an unpleasant odour. The pro- duct is received, in this state, from the tar distillers. The proportion borne by this acid to the amount of tar treated in its production is about 1-3 per cent. The impure or crude carbolic acid consists of carbolic and cresylic acids, and their homologues? together with a variety of im- purities. It is next subjected to a process of fractional distillation, which separates the carbonaceous matters and the water, the latter amounting to about 15 per cent. of the whole. This operation is conducted in the apparatus shown in Fig. 491 ; A is a circular still of wrought iron, 4 ft. in diameter, 6 ft. high, and provided with a dished bottom ; it is set in brickwork (as shown in Fig. 492), with a double series of flues, one to heat the upper portion of the sides, viz. the space included between e and /; the other, to heat the sides from/ 493 downwards to g ; above the level of e, the still is furnished with a manhole a; on to the top of the still, a cast-iron head and arm B is bolted, as shown at b b, the head B being fitted with a flange for that purpose ; at c, another flange is cast on the arm B, for the reception of a flange c of the leaden condensing worm C ; this condensing worm is of 2 in. bore at the commencement, diminishing to 1 in. at the outlet d. The distillate which escapes at d is collected in metallic coolers, about 22 in. high, holding about 12 gallons, and of the shape indicated in Fig. 493. They " " are placed in troughs, and surrounded by a refrigerating mixture, produced by some cooling apparatus, such as Kirk's, or Siddeley and Mackay's, refrigerating machine. The last is shov,-n in Fig. 494; A is the refrigerator; B, the vacuum pump; C, the condenser; D, the etaer meter; E E, the water pumps; F, the hand pump; G, the hand-pump condenser; I, the 2 x 674 COAL-TAE PRODUCTS. steam engine. The refrigerator A, a copper tubular vessel, is charged with the requisite supply of liquid ether, which, by the action of the vacuum pump B, is evaporated, drawn away in the form of vapour, and passed into the copper tubular condenser C ; here, under slight pressure, and by the aid of a stream of water, it is again reduced to its liquid state, and is thence returned through the ether meter D to the refrigerator A, to be re-evaporated. Thus the same ether is used continuously, with inappreciable loss. The ether meter D regulates the flow of the liquid ether to the refrigerator, rendering the machine self-acting. To utilize the cold produced by the evaporation of the ether, an uncongealable liquid, such as very strong brine, or a solution of calcic chloride, is forced by the pump E through the tubes of the refrigerator A, parting with its heat to the ether vapour on its passage, and leaving that vessel at a temperature of 10 to 7 (14 to 20 F.) thus many degrees below freezing point to be used in the freezing tanks, where the coolers represented in Fig. 493 are placed. The carbolic acid requires a long time for cooling; but solidifies finally in the form of thick acicular crystals of impure acid, which have lost their carbonaceous impurities so far as to be only slightly drab-coloured; and, though strongly oloriferous, their smell is by no means unpleasant. After removal from the freezing tank, the coolers are drained, by withdrawing the cork that is inserted in the aperture at the bottom. The liquid present escapes, and leaves a perfectly white acid, of indefinite crystalline form, fusing at about 29 (85 F.), but still possessing a strong odour. This is known as Calvert's " No. 3 " acid. Neglecting this " No. 3 " acid for the present, it will be well first to follow the mother-liquor which has been drained from it. This is placed in a still, similar in all respects to that already described ; 300 gallons of the liquid, of which a very variable proportion will be water, are redistilled, until there only remains in the bottom of the still about 30 gallons of a pitchy residue, which is run oif, while hot, in a fused state. The distillate is conducted through a leaden worm surrounded by water, for condensation, and thence into coolers. In this product, there is present a certain amount of crystallizable carbolic acid, as well as more or less of cresylic acid. This latter, which is soluble in about 80 parts of water, and whose boiling point is 190-200 (374-392 F.), is a constituent of all impure commercial carbolic acids, and is extensively used as a disinfectant, being frequently sold, for this purpose, under the name of " crude " or " liquid " carbolic acid. It may here be mentioned that there has grown up a practice of passing off, under this name, mixtures of tar oils, containing usually only a small percentage of carbolic acid, and sometimes even none at all, their general appearance and odour preventing their ready distinction, by the unscientific public, from the genuine acid. Now the value of the liquid for disinfecting purposes depends upon the quantity of carbolic and cresylic acids present in it, and upon its CARBOLIC ACID. 675 freedom from tar oils, for these, even if containing a small percentnge of carbolic acid, are them- selves comparatively valueless for disinfection, and, beiug insoluble in water, hinder the solubility of the carbolic acid. No liquid carbolic acid should be purchased, therefore, without a guarantee from the vendor as to its composition. A ready method of testing liquid carbolic acid, to ascertain its genuineness, is to measure off a given volume in a graduated glass, and then to add to it twice its volume of a pure caustic soda solution of 14 Tw. at 15 (60 F.). As carbolic and cresylic acids are both soluble in tins solution, the "liquid" acid should, if genuine, entirely dissolve, on shaking the mixture well together. The test for the crystallized acid is its fusing point; and, for the liquid acid, its solubility. F. C. Calvert and Co. do not sell this liquid acid in its impure state; they subject it to another distillation, and remove all traces of sulphuretted hydrogen, producing a very slightly- tinted, clear liquid, having a much less rank odour. This they distinguish as " No. 5 " acid, which they sell in bulk (casks, &c.) ; 6s. per gallon is the retail price. By redistilling this " No. 5," they get a still purer acid, called " White No. 5," which is the ordinary liquid acid sent out by them in bottles. This, as well as the preceding quality, is guaranteed to contain not less than 85 per cent, of carbolic and cresylic acids, and to be free from tar oils and sulphuretted hydrogen. To return to the " No. 3 " acid, fusing at 29 (85 F.). This is redistilled in the same kind of still ; but the worm for condensing the gases as they are evaporated has now to be made of zinc, instead of lead, as the latter metal would colour the product. The distillate is run into coolers of tin or zinc, where it is allowed to cool in the air down to 32 (90 F.). The coolers are then pierced, to drain off the liquid for reworking, leaving a mass of pure white crystals, fusing at 35 (95 F.), and corresponding with the acid produced by Laurent. This is Calvert's " No. 1 Com- mercial" acid, used chiefly for the manufacture of the various carbolic acid colours. It is frequently sold as purporting to be " B. P." quality ; but to obtain the real B. P. acid, it is necessary to remove from this commercial acid all traces of sulphuretted compounds and coal-tar bases, and to rectify it in ordinary glass swan-neck retorts of about 4 gallons capacity, and having long glass tubes as condensers for the distillate. Here the acid must be treated and evaporated almost to dry ness. The cooled distillate has the same fusing point as the acid whence it is derived It is soluble in 20 parts of water, and should be used exclusively for surgical applications. It forms Calvert's " No. 2 Medicinal " carbolic acid, and is the only one which fulfils all the conditions of the British Pharmacopoeia, drawn up by the late Dr. Grace Calvert. In order to produce a more perfectly pure carbolic acid, advantage is taken of Lowe and Gill's patented invention (1874), whose object is to effect and facilitate the separation of carbolic acid from the cresylic and other liquid tar acids contained in mixtures of these products, which, when dehydrated by distillation in the usual manner, are crystallizable at 17-35 (62-95 F.). The following method is adopted : It is first ascertained whether the acids are partially or wholly hydrated ; should they be in a dehydrated state, they must be hydrated by the addition of water to the amount of 5-30 per cent. The hydrated acids are then placed in suitable vessels surrounded by a cooling mixture, or circulating fluid, of a temperature sufliciently low to effect the separation of more or less hydrated carbolic acid crystals, say 9 to 13 (15 to 56 F.). This refrigerating process being complete, the mother-liquors are drained or otherwise separated from the crystals, and are rectified in the manner already described, to bring them within the limits of the crystallizable temperatures for re-treatment. The crystals may be purified from all traces of the mother-liquors, by re-crystallization, either by partial fusion, or by solution in water and subsequent refrigeration of the water solution to a temperature of about 1 (33 F.). The crystals are then dehydrated by fractional distillation, and thus is produced a carbolic acid crystallizing at 38-42J (100-108-5 F.), and boiling, with thermometer in liquor, at 181-182 (358-360 F.) under an atmospheric pressure of 29 -26 in. of mercury. Calvert and Co. drain away the mother-liquor from this acid, and subject the latter to a special treatment, rendering it perfectly free from traces of sulphuretted compounds and coal-tar bases, then to a further rectification in glass, producing a chemically pure acid, fusing at 42 2 (107 9 F.), boiling at 182 (360 F.), and soluble in 12J parts of water. This pure acid is composed of acicular crystals, and is entirely free from tarry taste and odour; it is known as "No. 1 Medicinal " acid, and is used nearly exclusively for internal administration. It is sold in bottles of 1 oz. and upwards, the retail price being 10s. per Ib. Besides Calvert's soaps, containing specific proportions of carbolic acid, there are two prepa- rations of the acid which call for a short notice, viz. carbolized powder and carbolized tow. The former consists of a mixture, in the proportion of 15-20 per cent, of liquid carbolic and cresylic acids, and an inert base, such as silica. Perhaps silicate of alumina, or china clay, is the best ; lime, which is sometimes used, is not so suitable, on account of its destructive nature to carpets, &c., should it by accident be spilled on them ; it would also set free ammonia, if present in the matter to be disinfected. In this manner, is produced a disinfecting powder, in which the acid is left in a free state, thus allowing it to act by direct means, or by evaporation. 2x2 676 COAL-TAK PKODUCTS. In order to readily detect the amount of real carbolic acid in a disinfecting powder, K. Le Neve Foster, F.C.S., has devised the following rough method: -Place 1000 gr. of the powder in a small tubulated retort ; heat the retort gradually, until the liquid distillate ceases to drop (a brisk heat is required towards the end of the operation) ; collect the distillate, which will condense in the tube of the retort, ia a graduated cylinder grain measure, and allow it to settle for one hour, when the amount of oily liquid and water may be read off ; the oily liquid should represent the amount of carbolic acid ; to ascertain if this be so, to one volume of it, add two volumes of a solution of pure caustic soda, 14 Tw. at 15 (60 F.), which will entirely dissolve the carbolic acid ; if any remains undissolved, it will probably consist of either heavy or light oil of tar, the most frequent adulterants of carbolic acid, and, in some cases, entirely substituted for it. The above process will, if carefully worked, give within \ per cent, of the amount of carbolic acid really contained in the powder. Carbolized tow is a preparation of tow with carbolic acid ; it is recommended by the ' British Medical Journal,' in decided and unqualified terms, and may with advantage be used for most of the surgical purposes to which lint, sponge, and cotton wool are now applied. Other Processes. Schnitzler proposes to produce colourless crystallized carbolic acid, in the following manner. Kaw phenate of soda is thoroughly heated in a copper still ; water, naphthalene oils, and a little carbolic acid pass over, and the fire is removed when the distillate begins to run milky: 15 kilos, require about ten hours. The greater part of the carbolic acid remains combined with the soda, as a solid mass ; the temperature of the vapour during distillation may reach 170 (338 F.) ; the solid residue is afterwards dissolved out in triple the quantity of water necessary. This liquid is allowed to settle for some days, when certain impurities are deposited. Dilute sulphuric acid is then added to the clear liquid, the carbolic acid is decanted and distilled in glass vessels; water passes over first, then pure carbolic acid, which crystallizes entire, and lastly a less pure carbolic acid, which, even after crystallization, retains some oily impurities. In order to obtain carbolic acid in a dry state, recourse must be had to digestion with chloride of calcium, followed by a new rectification ; if required pure, only that portion which boils at 188 (370 F.) must be received ; the distillate, by refrigeration, furnishes crystals of the acid, which must be drained, dried, and preserved from contact with the air. To ascertain the percentage of carbolic acid in dead oils, &c., there is a simple method, based upon the boiling point of the acid. The substance is heated in a still, and the oily liquid distilling at 150-200 (302-392 F.) is well mixed with a solution of caustic soda, which combines with the carbolic acid, forming a compound which may be readily decomposed by any strong mineral acid. Briefly, the process amounts to a preparation of carbolic acid, carried on so carefully as to render it suitable for ascertaining quantities. Professor Church remarks that the rank of carbolic acid as a most valuable contribution from chemistry to medicine is so well assured as to require no confirmation, yet there is an objection urged against the substance, which has some apparent force, simply because the preparations of commerce are so seldom free from a gas-like or naphthalic odour, which, though entirely foreign to carbolic acid itself, has condemned its use in some quarters. He adopted the following simple plan of purifying such acid : 1 Ib. of carbolic acid is poured into 20 Ib. of cold distilled water, taking care not to permit the whole of the acid to enter into solution. With a good sample, if after repeated shaking at intervals, 2-3 ounces of the acid remain at the bottom of the vessel, this will be sufficient to hold all tlv- impurities ; with bad samples, less water or more acid must be used. The aqueous solution is siphoned off, and filtered till perfectly clear ; it is then placed in a cylinder, and common salt is added with agitation tfll it no longer dissolves. On standing, the greater part of the carbolic acid will be found, as a yellow oily layer, on the top of the saline liquor, and may be removed for use. As it contains 5 per cent, or more of water, it does not generally crystallize ; but it may be made to do so by distilling it from a little lime. The portion collected up to 185 (365 F.) or thereabouts has, at ordinary temperatures, scarcely any odour, save a faint one resembling that of geranium leaves. The saline liquor remaining may be distilled, to yield a second portion of pure carbolic acid, which will serve as a disinfectant and deodoriser. Impurities. One of the moat common impurities found in carbolic acid is coal-tar oil. This can easily be detected by mixing the suspected acid with a solution of pure caustic soda, 14 Tw. at 15 (60 F.), one volume of the former to two of the latter, and agitating. If pure, the solution will be complete ; the amount left undissolved after settling will indicate the proportion of im- purity. Pure carbolic acid gives a blue colour to pine wood previously treated with hydrochloric acid : a green colour indicates aniline ; and a brown, pyrrhol. Poisoning and Antidotes. In cases of poisoning with carbolic acid, Dr. Calvert recommends the administration of copious doses of castor and sweet oils. In cases of external burns, glycerine should be immediately applied, and the affected parts should be repeatedly washed with it. Dr. J. Hase- mann recommends a strong solution of saccharate of lime, as an antidote. Carbolic acid is a most powerful poison ; it can cause death even when it acts only upon the skin, and it should never CAEBOLIC ACID. 677 be sprinkled upon floors, nor upon any surface likely to be used as a seat, unless it be in perfect solution in water. In an impure state, or in solution, it has been swallowed in mistake for porter or spirits. The signs indicating poisoning by carbolic acid are especially the whiteness of the mouth, tongue, and fauces, and the characteristic odour. Dr. Sansom recommends the immediate administration of the white of eggs. Tests. Besides the tests already indicated on p. 41, attention is directed to the following: (!) Dr. W. F. Koppeschecar's method of estimating volumetrically, by the aid of a titrated volume of hydrobromic acid, fully detaili-d by him in the ' Moniteur Scientifique,' April, 1878. (2) Prof. E. W. Davy observes that a solution of molybdic acid in sulphuric acid produces a light-yellow or yellowish-brown tint, developing into purple. This test appears not to be interfered with by the presence of organic substances, and affords a means of distinguishing creasote from carbolic acid, a matter of commercial importance, much of what is sold as creasote being little else than carbolic acid. Eecent files of the ' Analyst ' may also be consulted with advantage. Uses. The next consideration will be some of the uses which may be made of carbolic or phenic acid (01 rather alcohol, for its properties are alcoholic rather than acid), for sanitary, domestic, agri- cultural, and manufacturing purposes. The antiseptic or germ-killing properties of this substance are very remarkable. Research and discovery have shown that all fermentation and putrefaction are due to the presence of microscopic animals or vegetables, which, during their vitality, decompose or change organic substances, so as to produce the effects which are witnessed. As carbolic acid exercises a most powerful destructive action upon these microscopic and primitive sources of life, it is therefore an antiseptic and disin- fectant, much more active and much more rational than those generally in use. It is necessary here to make a few remarks, explanatory of the distinctions between deodorizers, disinfectants, and antiseptics. All substances acting merely as deodorizers are neither disinfectants nor antiseptics, as they simply remove the noxious gases and odours emitted from organic matters whilst in a state of decay or putrefaction, without having the property of arresting decomposition or fermentation. It has been proved that the source of infection does not lie in the noxious gases and bad smells (which are simply indicators of its probable existence), but in microscopic spores floating in the atmosphere, and which are ultimately developed and propagated. Disinfectants are those bodies which prevent the spread of infection. Under this head, may be classed bleaching powder or chloride of lime, sulphurous acid, and permanganate of potash. They act first as deodorizers, and then as disinfectants ; but they must be employed in large quantities to thoroughly oxidize or burn up organic matters, so as to prevent them from again entering into decomposition when exposed to the atmosphere. They are, in fact, rather destructive agents than disinfectants properly so called, and are never antiseptics. Antiseptics, such as corrosive sublimate, arsenious acid, essential oils, carbolic acid, &c., act as such by destroying all source of decay and decomposition, that is to say, they destroy or prevent the formation of the germs of putrefaction and fermentation, without acting upon the animal or vegetable matters present. The advantage of their use is, therefore, that they act, when used in small quantities, upon the primary source of a state of decay in all organic matters. Further, they are deodorizers, inasmuch as they arrest the progress of that decomposition which generates offensive odours ; thus, while an antiseptic is, of necessity, at the same moment, a deodorizer and a disinfectant, these latter are not necessarily, and probably never are, antiseptic. Now disinfectants, such as chlorine, permanganate of potash, or Condy fluid, operate by oxidizing not only the gaseous products given off by putrefaction, but also all organic matters with which they may come into contact ; whilst carbolic acid, on the contrary, merely destroys the causes of putrefaction, and, at the same time, sterilizes the organic matter, rendering it inert as a pabulum for the reproduction or the nutrition of disease germs. The great difference which distinguishes them, therefore, is that the former deal with the effects ; the latter, with the cause. Again, these microscopic ferments are always in small quantities, as compared with the substances on which they act ; as a very small quantity of carbolic acid suffices to prevent the decomposition, its employment is both efficacious and economical. Moreover, carbolic acid is volatile, it meets with and destroys the germs or sporules as they float in the atmosphere ; but this cannot be the case with Coiidy fluid, nor with chloride of zinc or iron, which are not volatile, act only when in solution, and are mere deodorizers. This is why carbolic acid was used with such marked success, in England^ Belgium, and Holland, during the prevalence of cholera and cattle plague. Professor Crookes did not meet with a single instance in which the plague spread on a farm where the acid was freely used. The antiseptic properties of carbolic acid are so powerful, that one-thousandth, and even one five-thousandth, part will, for months, prevent the decomposition, fermentation, or putrefaction of urine, blood, glue solution, flour paste, faeces, &c., &c. ; and its vapour alone is sufficient to preserve meat in confined spaces for weeks ; and even a little of its vapour in ordinary atmosphere will pre- serve meat for several days, and prevent its being fly-blown. Indeed, one ten -thousandth part haa 678 COAL-TAR PRODUCTS been found sufficient to keep sewage sweet, for Dr. Letheby found that, through the use of such a quantity of carbolic acid in the sewers of London, during the existence of cholera in 1866, the sewers of the city were nearly deodorized. Some experiments made by Dr. Culvert, on the comparative powers of various products ordinarily used as antiseptics, consisted in placing in bottles (not corked) solutions of albumen and flour paste ; to these were added various proportions of some substances patronized as antiseptics ; the following table shows the results obtained : Antiseptic employed. Percentage of Antiseptic. Time in which It acquired an offensive odour. Temperature from 70 to SO F. Albumen. Flour Paste. MeDougall's disinfecting powder Carbolic disinfecting powder (15 per cent, acid) Chloralum (made lately) Chloride of zinc 5 5 2 2 5 5 2 2 2 11 days Remained sound 9 days 15 days 16 days 4 days 11 days Remained sound Remained sound 5 days 25 days Remained sound 10 days Remained sound 14 days 6 days 25 days Remained sound Remained sound 7 days Chloride of lime .... ... Permanganate of potash Tar oil Carbolic acid None These figures show clearly that the only true antiseptics are carbolic and cresylic acids, for they continued their action till tlie albumen solution and paste dried up; and these results coincide with those obtained by Professor Crookes, and by Drs. Angus Smith and Sansom. It may be remarked that disinfectants are of two classes, those which act by oxidation, destroying the organic substances which give rise to the infection, such as permanganate of potash, bleaching powder, and nitric acid ; and those which act by their presence, undergoing no decomposition them- selves, but appearing to poison, or render innocuous, the germs of disease. To the latter class belong camphor, and sulphurous and carbolic acids. If deodorizers are merely intended to remove the noxious odour from any mass of matter in a state of decay or decomposition, they may be used with advantage: such are chloride of manganese, chloride of lime, sulphate of iron, permanganate of potash, chloralum, &c. But if it is desired to prevent the decomposition of organic matter, and to render it inert for the reproduction and nutrition of disease germs, carbolic and cresylic acids seem to be the only two substances to be relied on. As the products given off from decaying organic matter are well known to facilitate the decom- position of similar classes of substances to themselves, if placed in close proximity (the atmosphere, no doubt, conveying the germs), Dr. Calvert made the following experiments, with a view of ascer- taining which of the undermentioned products would possess the most active power in destroying euch germs, and thus preserving the animal substance from decay. At the bottom of wide-mouthed pint bottles, he placed a known quantity of each of the antiseptics, and suspended over them, by a thread, a piece of sound meat. By daily examination, it was easily ascertained when the meat became tainted, and when putrid. The subjoined table indicates the results : Antiseptic used. Became Tainted. Putrid. Permanganate of potash Chloralum McDougall'n disinfecting powder . Chloride of lime Tar oil 2 days 2 days 12 days 14 days 16 days 19 days Did not become it up and becat Ditto Ditto 4 days 10 days 19 days 21 days 25 days linted, but dried ae quite hard. Ditto Ditto Chloride of zinc Carbolic disinfecting powder (15 perl cent, acid) / Carbolic nc'd Cresylic acid The following account of a series of experiments, undertaken by Hare and Longstaff, with a yiew of determining the relative merits of a few so-called disinfectants recently introduced, as com- pared with others that have been long before the public, will be of interest. It should be premised that they only deal with the relative values as antiseptics. A quantity of urine was well mixed with a sufficient quantity of water to prevent the deposition of urates ; 100 c.c. of this mi xe d urine was placed in each of thirty-four vessels. To two of them, CAEBOLIC ACID. 679 5 c.c. of tap-water were added ; and to the others, the various antiseptics in the following amounts : Of the solids, 0' 1 grm. with 5 c.c. of water ; of the liquids miscible with water, 5 c.c. of a solution containing O'l c.c. of the antiseptic; and, in the case of the liquids not miscible with water, 5 c.c, of a recently agitated emulsion of the same strength. Thus, in each case, the amount of antiseptic used was 1 per cent, of the volume of urine experimented on. All the experiments were in dupli- cate (I. and II. in tables). The only phenomena looked for were the appearance of mould, and a dis- tinct putrefactive odour : Antiseptic, 0-1 per cent. Day on which Mould appeared. Day on which Putrefac- tive Odonr was distinct. Water only I. II. I. II. 9 10 None by 9 10 13 8 8 8 None by 10 8 9 12 9 9 9 10 75th day 9 10 14 8 9 8 14th day 10 9 9 9 8 14 13 None by 12 ' 15 18-23? 10 18-23? 12 8 14 9 15 13 14 15 13 18-23?* 75th day 12 10 18-23?* 11 18-23?* 12 8 14 10 11 12 14 11 Terebene (Dr. Bond's) Carbolic acid (Calvert's No. 5) . Burnett's fluid Condy's red fluid Turpentine Borax Cupralum (Dr. Bond's) . Ferralum (Dr. Bond's) . ... Sodium salicylate Sanitas (aromatic, No. 3) Sanitas (inodorous, No. 3) . . McDougall's fluid Sanitas (aromatic, No. 1) .. Sanitas (inodorous, No. 1) . . * Some uncertainty as to exact day, owing to absence. As regards mould: Burnett's fluid, chloralum, borax, cupralum, and sanitas failed to delay its appearance ; terebene, Condy's fluid, sodium salicylate, and McDougall's fluid had but little effect turpentine delayed it four or five days ; ferralum was only under observation fourteen days, during which no mould appeared ; carbolic acid appeared to prevent it entirely, since, after seventy-five days, the urine had evaporated nearly to dryness, without the slightest trace of mould having been As regards putrefactive odour : Its appearance was delayed a few days by terebene (one experi- ment), turpentine, and borax ; no putrefactive odour appeared where carbolic acid had been added ; the other substances had no effect. A few experiments were made with the fluids after they had become putrid, by adding more of the antiseptic until the odour was removed, and then noting when it again became perceptible. These indicated that terebene, cupralum, sodium salicylate, and McDougall's fluid rank highest as deodorizers, while Condy's fluid and sanitas (aromatic, No. 3) have least power. But too much value must not be given to experiments which depend solely on the sense of smell, since it is very deceptive, and different observers disagree about odours. Indeed, in the case of McDougall's powder, which has a very disagreeable smell of its own, it was found impracticable to decide whether an additional odour of putrefaction was or was not present. The medicinal applications of carbolic acid are numerous. It is used as a caustic ; for pul- monary diseases ; in several skin diseases ; in the treatment of burns and scalds ; and in many other ways. From a hygienic point of view, the uses and applications of carbolic acid are more general than those of any other article, or perhaps even than all the other agents taken together. The trifling disadvantage of its disagreeable odour is removed in proportion as the oils and other tarry matters are more perfectly separated; and, in the best crystallized samples, there scarcely remains any odour at all, and that by no means disagreeable to persons in general. All the evidence that can be collected goes to show that the odour and vapour are wholesome and never hurtful, even by pro- longed exposure to a saturated atmosphere. It is said to be a tonic to those who work in it, and to have a general tendency to robust health. Its antiseptic or preservative powers have been long known, though but recently investigated ; and generations of men have protected and preserved their meats and fish through its agency as derived from smoke. Small animals, insects, &c., killed by it, dry up in the air without putrefaction ; by its use, crawling insects of all kinds can be pre- vented from attacking trees. Its employment in stables, shippons, slaughterhouses, pigsties, kennels, middens, and privies, does not cause the manure to deteriorate. For foot and mouth disease, scab, and foot-rot, it is an 680 COAL-TAE PRODUCTS. efficacious remedy. By its use, the trade in skins and bones from Australia, South America, &c., is being benefited. Often the refuse of cattle, especially the bonee, come to this country in a half putrid state, emitting an insupportable odour, and fit only for manure ; with carbolic acid treatment, they arrive perfectly preserved, and can be employed for all the uses to which green or raw bones are usually applied, thus increasing their value very considerably. Hides also frequently arrive putrid, although they have been dried or salted ; it is only necessary to immerse them for twenty-four hours in a solution of two per cent, of carbolic acid, and to dry them in the air, to secure their preservation. It is probable that, in a short time, the blood, intestines, and other parts of the animals slaughtered in such numbers in stock-raising countries, will be treated with carbolic acid, and shipped to this country for manure. The acid is already used in the preservation of guts at the gut works ; for keeping anatomical preparations ; and for the preservation of all animal matter. It is also used for preventing the decomposition of the various albumen, flour, and starch thickeners used in calico printing, as well as for gelatine or bone size, employed for sizing fustains and other cotton goods. DERIVATIVES FKOM CARBOLIC ACID. Of these, the most important is carbazotic, picric, or tri- nitrophenic acid (see p. 40). From this acid, are produced several useful compounds employed as dyes, explosives, and therapeutic agents. Picramic Acid. This was obtained in the first instance by Wcehler, by the action of sulphate iron on picric acid, and neutralizing with caustic barytes ; a deep brown salt was produced, from which the baryta was separated by sulphuric acid, leaving an acid which was called " nitrohaB- matic." But the process by which picramic acid is now manufactured is due to Aime Girard, and depends upon the action of hydrosulphate of ammonia on picric acid. Picramic acid imparts to silk a series of brown tints, similar to those obtained from catechu. Isopurpurate Potash. This is obtained by mixing a solution of 2 parts cyanide potassium in 4 parts water, with solution 1 part picric acid in 9 parts boiling water, with constant agitation ; on cooling, it solidifies to a red crystalline pulp ; this is strained, pressed, triturated, filtered, washed, re- dissolved in boiling water, filtered, and left to crystallize, when it forms reddish-brown scales, with a green lustre ; these dissolve in water and alcohol, yielding a purple-red colour. Isopurpurate ammonia, Murexid, or Soluble Garnet. .This is formed by decomposing isopurpu- rate potash by means of ammonium chloride. Isopurpurate aniline. This results from a mixture of 42 parts hydrochloride aniline, and 100 parts isopurpurate potash, and yields browns and reds. Picrates Ammonia, Potash, and Soda. These are formed by neutralizing a hot solution picric acid by one of the agents named. Their chief use is owing to their explosive qualities, but the ammonia salt has been highly spoken of as a therapeutjc successor to sulphate quinine. Rosolic Acid, Aurine, or Yellow Coralline. This may be produced by the direct oxidation of car- bolic acid. The process generally adopted for its manufacture is due to Jules Persoz : A mixture is made of about 3 parts carbolic acid, 2 parts oxalic acid, and 2 parts sulphuric acid. The oxalic acid is added by degrees, and the whole is heated for some hours at about 160 (320 F.). The heating is best effected by Bunsen burners. During the reaction, more or less lively effervescence is produced, due to the disengagement of carbonic oxides, arising from the decomposition of the oxalic acid. The mass thickens and becomes reddish-brown. The operation is terminated when a sample thrown into ammoniacal water dissolves with a reddish-purple colour ; the fire is then with- drawn, and the compound is run off by a leaden siphon into cold water, to separate the greater part of the excess of sulphuric acid and the eulphophenic add formed. It is steamed up several times to complete the purification, and is then a pasty cantharides-green mass. This is dried in jacketed enamelled pans, by which it becomes hard and brittle. The whole process occupies about a week. It is soluble in alcohol, but not in water. Dr. Calvert discovered, in 1863, that rosolic acid thus prepared could be employed directly as a dye, and introduced it to dyers under the name of '' aurine," and to printers *o produce upon silk and albumenized cotton magnificent orange colours, like those of basic chromate of lead, or of turmeric. The calcium lakes of aurine are largely used by paper stainers. Peonine, or Bed Coralline. In 1860, Persoz discovered that rosolic acid, heated under pressure with ammonia, gave rise to a red substance which he called "Peonine." Gunion, Marnas, and Bossuet perfected the manufacture, and gave it the name of " Red coralline." It is prepared by introducing into a digester 1 part rosolic acid, and about 3 parts commercial ammonia, and heating the mixture with an oil bath for three hours at a temperature not exceeding 150 (302 F.). The mass, withdrawn from the apparatus after cooling, forms a thick liquid of golden-crimson colour, which is precipitated on addition of hydrochloric acid. It imparts a brilliant scarlet to silk and worsted. Azuline The same firm introduced, towards the end of 1860, a blue dye, derived from rosolic acid, which they called "Azuline." This is prepared by heating for several hours, at about 180 (360 F.), a mixture of 5 parts rosolic acid and 6-8 parts aniline, and which is purified by repeated NAPHTHALENE DERIVATIVES. 681 treatment with sulphuric acid and benzol, constituting, -when dry, a red mass having gold- coloured tints. Though discovered before the aniline blues, which have since become formidable rivals, it is still manufactured in competition with them. Veridine. In 1863, was produced the first green derived from carbolic acid ; but it has not been able to compete with aniline greens. It was obtained from a mixture of aniline, and benzoic and rosolic acids. Phenicienne. This was discovered, in 1863, by M. Both; it produces fast colours, from a garnet- red to a golden-buff, and is obtained by the action of nitro-sulphuric upon carbolic acid. Sulpho-carbolic Acid and its Salts. When one equivalent carbolic acid is slowly mixed and heated with two equivalents concentrated sulphuric acid in an earthenware pan, a definite compound is formed, called sulpho-carbolic acid C 6 H 6 SO 4 , which is dissolved out by the addition of water. The heat must be applied carefully, on account of the carbonizing influence of the sulphuric acid. The sulpho-carbolic acid is freed from sulphates by adding carbonate of baryta, which falls to the bottom of the vessel as sulphate of barium, and the liquid acid may be decanted. It forms a great number of definite salts, every one of which is soluble in water. The most important are those of soda, potash, zinc, iron, magnesia, and lime ; all are largely used for pharmaceutical purposes. Salicylic Acid. Salicylic acid (to which much attention has lately been drawn), originally a pro- duct obtained in the laboratory in small quantities from the plant called Wintergreen (Gaultheria procumbens), is now being produced from carbolic acid on a commercial scale on the Continent, by the process of Professor Kolbe, of Leipzic. Carbolic acid is heated with solid hydrated oxide sodium in a closed iron retort, the temperature being maintained at about 183 (361 F.), till the water, and the excess of carbolic acid, have passed over into a receiver, dry carbonic gas being passed into the contents of the retort in a continuous stream. The temperature is finally made to exceed 200 (392 F.), the mass becomes solid, and the operation is terminated when but little residual acid distils over. The contents of the retort, after the above operation, contain some salicylate of soda and free carbolic acid ; they are dissolved in water, and by the addition of slight excess of hydrochloric acid to the solution, the salicylic acid is precipitated. It is then washed, and thus purified from all traces of the hydrochloric acid. The salicylic acid thus produced is a yellowish- white powder, devoid of smell, fusing, when pure, at 158 (316 F.), sparingly soluble in cold water, but readily soluble in boiling water. Its chemical composition is C : H 6 Oj,- or, in other words, 1 equivalent carbolic acid + 1 equivalent carbonic acid. It may be sublimed unaltered ; but when heated strongly with powdered glass or sand in a retort, it is resolved into carbolic and carbonic acids. It possesses antiseptic properties, though in a less degree than carbolic acid. As a general disinfectant, it cannot become a rival to carbolic acid, owing to its lesser antiseptic power, and its higher price, this latter being entirely dependent on the cost of the carbolic acid from which it is manufactured. It is, however, being now employed in some of the German hospitals. NAPHTHALENE DERIVATIVES. Clavel (No. 2296, 1868) obtains a red colour from napthylamine Cq. v.), which is acted upon at 121 (250 F.) with equal parts by weight glacial acetic acid and nitrite of soda, until the red colour is produced. The colour, after treatment with water, is dissolved in warm diluted acetic acid, from which it may be separated again, by common salt, for purification. Its solution in alcohol or weak acid may be used for dyeing or printing ; it is less altered on exposure than rosaniline reds. A scarlet has been obtained by treating the sulphate of naphthyl- amine with nitro-muriatic acid. Magdala Pink, or Hofmann's Naphthalene Ped. This colour is obtained by heating together amido- azo and amido-naphthalenes (q. v.), and is sold as a brown crystalline powder, which is the hydro- chlorate, soluble in alcohol with a deep-red colour, almost insoluble in cold water, but soluble in boiling water. Its alcoholic solution is precipitated by ether in a crystalline, brownish powder. Its dilute solutions have a splendid bright-red fluorescence. A few drops of a concentrated solution dropped into a test-tube full of alcohol, will take, by reflected light, a bright-red cloudiness, as if turbid ; but by transmitted light, will appear perfectly clear, with a fine rose-red tint. This is the most important colour from naphthalene ; but its manufacture being more troublesome than that of the aniline colours, it has not been much taken up. It does not equal aniline colours in deeper shades, but gives brighter tints. It has been pointed out as a source of other colours. Napthylamine Violet. By using the same reaction as with aniline, arsenic acid, &c., violet colours have been obtained, but they are wanting in brilliancy and freshness. Ballo obtains a very fine violet, by heating acetate rosaniline with naphthylamine ; its alcoholic solution dyes equal to the aniline colours. Violacine. A blue dye of this name is obtained from an impure naphthalene by treating with strong caustic alkali, and submitting the product to oxidation (No. 3080, 1873). It is said to dye a fast blue colour with a reddish tinge, which, by complete purification, turns yellowish. By oxidizing naphthalene with chromic acid, a beautiful red matter is produced, to which Laurent has given the name of " Carminnaphte " ; it dyes silk and wool violets having orange or reddish, shades. 682 COAL-TAR PRODUCTS. Naphthalene Yellows. Price (No. 89, 1869) produces a sulpho-acid by heating at 100 (212 F.) about 1 Ib. naphthalene with 1 Ib. concentrated sulphuric acid, till most of the former is converted into sulphonaphthalic acid, which is neutralized by an alkaline solution. By evaporation and fusion with an alkali, naphthol is obtained on precipitation with a dilute acid. The naphthol or naphthylic alcohol is then dissolved in strong sulphuric acid, to which warm dilute nitric acid ia added. The solution passes through different tints, and finally assumes a yellow ; on cooling, the colouring matter crystallizes out. It may be purified by solution in alkali, and reprecipitution with muriate of ammonia. Manchester Yellow. On the large scale, this is obtained by adding sodium nitrite to a solution of amido-naphthaleue and hydrochloric acid, and boiling the diazo-naphthalene chloride thus formed witli nitric acid. Bullo heats 1 part naphthyLmiine with 4-6 parts nitric acid (sp. gr. 1*35), as long as brown vapours are produced. The dinitro-naphthol thus formed dissolves in alcohol, ether, and benzol; and crystallizes in fine citron-yellow needles. It is the finest and purest yellow knowu ; it dyes silk and wool all shades of yellow from bright citron to orange, and is largely used for dyeing wool and leather, and printing felt carpet ; 1 Ib. will dye 200 Ib. wool an inten>e yellow. Chlor-oxy-n tphthalic Acid. Laurent and Casthelaz have adopted this substance for dyeing (1865, No. 1605). It dyes unmordanted wool an intense red; by boiling with zinc in an alkaline solution for fifteen or twenty minutes, the liquid becomes yellow, from which hydrochloric acid deposits a brownish flocculent precipitate ; its alcoholic solution dyes wool and silk violet ; on cotton, the same may be fixed with albumen. The dilute solution dyes blue on wool, silk, and mordanted cotton : acids redden it. Phthalic Acid, or Anhydride ; C 8 H 6 O 4 . This is formed by strongly oxydizing naphthalene. It melts at 175 (347 F.) from boiling water, and crystallizes in plates or thick prisms. It has the same relation tobenzoic acid as the latter has to benzol. When calcium phthalate is heated with quicklime to 300 (572 F.), it is converted into calcium benzoate ; but, at higher temperatures, pure benzol is foimed. Laurent and Casthelaz have proposed to obtain artificial benzoic acid by this reaction. Qninizarine ; C U H 6 O 2 (OH) 2 . When phenols are treated with phthalic anhydride, or when sulphuric acid, phthalic anhydride, and hydroquinone are heated together, quinizarine is formed ; it crystallizes from ether in yellowish plates, and from alcohol in deep red needles. It resembles alizarine, but gives a different absorption spectrum. Galline; C 20 H 12 O 7 . By heating at 190-200 (37-t-392 F.), till the mass acquires a pasty con- sistency, 2 parts pyrogallic acid and 1 part phthalic anhydride, the mixture turns red. It dissolves in alcohol, and, when filtered, may be precipitated with water ; this method may be used for its purificatin. On alum mordanted cloths, it dyes red thades resembling those of Brazil wood. Cceruline ; C 20 H 10 O 7 . This is obtained by heating gallin with 20 parts sulphuric acid to 200 (392 F.) ; the process is terminate when a sample heated with water gives brown flocks and a colourless solution ; the mass is then turned into a large quantity of water, and washed with boiling water. It dyes alum-mordanted fabrics a greenish colour ; and those mordanted with salts of iron, brown. Resorcine, CH 4 (CH) 2 , is obtained by fusing several resins ; its source is disulpho-benzolic acid, which, by fusion with caustic alkali, yields a mixture whence the resorcine is extracted by ether. Bindschedler and Busch give the following for its preparation : 90 kilo, fuming sulphuric acid (80 B.), and 94 kilo, pure benzol, flow gently together through a cohobator into a cast-iron still, and are constantly agitated ; the vapours are condensed, and fall back again into the still ; at the end of two or three hours, sulpho-benzolic acid is formed. The cohobator is closed, the still is connected with a condenser, and the temperature is raised to 275 (527 F.) for about twenty minutes ; the disulpho-acid thus formed is thrown into about 2000 lit. water and boiled; the excess of sul- phuric acid is removed by lime; the solution contains disulpho-benzolate lime. This is converted into a soda salt, which after filtering is evaporated to dryness ; CO kilo, are placed in a cast-iron boiler containing 150 kilo, caustic soda at 76 B. ; the whole is heated for eight or nine hours to 270 (518 F.), with constant stirring. It is cooled, dissolved in 500 lit. water with hydrochloric acid in slight excess, and kept boiling; when cool, it is filtered into copper cylinders, about 250 lit. capacity, supplied with agitating fans ; a current of ethylic ether percolates slowly through the liquid, taking up the resorcine. This solution is received in an enamelled still, where the ether is evaporated and returned to the cylinders ; this is continued until all the resorcine is taken up. The resorcine remains in the still, which is finally heated to 215 (419 F.); the resorcine then passes over almost chemically pure. Fluorescine, or Resorcine-Phthaline ; C 20 H, Z O S . This is formed by fusing 100 parts resorcine with 75 parts phthalic anhydride to 193 (380 F.), heating together for one hour ; on cooling, it is powdered, and is ready for use. It forms dark brown crystals, dissolving in ammonia with a red colour ; this solution exhibits, even when dilute, a most beautiful green fluorescence. It dyes silk and wool a splendid yellow. It is used principally as a source of cosine. ALIZARINE. 683 Eosine. When fluorescine is heated with bromine, a substance is produced, which, when treated with potash or soda, dried, and powdered, has a brick-red colour ; it dissolves in water, and dyes beautiful scarlet shades. Yellowish Eosine. To one kilo, fluorescine, stirred into 10 lit. alcohol, is added in a gentle stream 1 1 kilo, bromine with constant agitation. This converts the fluorescine into a soluble brown compound, which, by the further cautious addition of 1 1 kilo, bromine, is converted into a crys- talline precipitate of tetra-brom-fluorescine, this is washed with a little alcohol, stirred up in warm water, and taken up with caustic soda or potash, taking care to avoid an alkaline reaction. The solution is evaporated, when the tetra-brom-fluorescine salt of sodium or potassium is obtained as a crystalline deliquescent powder. It dyes a fine scarlet with a yellowish tint. Blueish Eosine. Fluorescine, and the necessary quantity of iodine are dissolved separately in alkaline water, and mixed. An acid is added, which, by setting free both the iodine and fluorescine, causes them to combine. A crystalline precipitate is deposited, soluble in dilute alkali, and forming the tetra-iod-fluorescine salt of sodium or potassium. It gives a blueish scarlet eosine, soluble in alcohol. Alcoholized derivatives are obtained by heating with alcohol and sulphuric acid in a cohobator. The methylic compound is more yellowish than the ethylic. These compounds are soluble in equal parts alcohol and water. Other eosine colours are obtained, but they have not yet met with much demand. The commercial salts are generally those of sodium. Griess (1877, No. 3698 ; 1878, No. 4728), obtains colouring matters by acting upon the diazo compounds of the nitro-phenols with certain derivatives of the phenylic series. Picramic acid is converted into its azo derivative, and, by treatment with carbolic acid, yields yellow or brown colouring matters ; a maroon is obtained by using resorcine or orcine instead of carbolic acid. Beta naphthol and the azo derivative of picramic acid gives purple ; either alpha naphthol or the sulpho- napthalic acids may be used instead. Poirrier, Rosenstiehl and Roussiir (1878, No. 4489), convert phthalamine into a sulpho conjugate body, which is afterwards nitrated into a diazo derivative ; this is united directly with phenols or amines for the production of direct colouring matters. With beta naphthol, a material is obtained which dyes wool a very intense red, as if produced by orchel. Alizarine; C 14 H 6 O 2 + (HO) 2 . This substance is found in the dried roots of Eubiacece, and forms the principal portion of the colouring matter of the madder plant (see Dye Stuffs). The very large consumption of madder in this country made the artificial production of the dye a matter of importance, hence England has taken the lead in developing the production of the colour from coal-tar. The source of artificial alizarine is anthracene, a product from which many other colours are probably destined to be derived. The only firm engaged in the manufacture in this country is that of Burt, Boulton, and Hey wood, Silvertown. The anthracene is first converted into di-brom- anthraquinone, di-sulpho-anthraquinonic acid, or di-nitro-anthroquinone (q.v.), which on fusion with potash, maintained until the mass assumes a fine violet colour, yields a melt from which the colouring matter is dissolved out by water ; this solution, treated with an acid, deposits alizarine as a yellow precipitate. The fusion with alkali is the most important step in the manufacture. The addition of water, the temperature, and the duration of melting, are of great moment. Too much water and too little heating will lead to the formation of hydro-products, or only oxyanthraquinone ; too great a heat burns the melt, and yields a dirty-green paste, which dyes greyish shades. If heated for too long or too short a time, a part of the sulpho-salt is reduced to anthraquinone, which cannot be easily separated from the alizarine, on account of the difficulty of filtering the alkaline solutions. The purity of the tones depends on the quality of the alizarine ; if a fine or blue alizarine is required, it is best to work on the " silver salt," which is the mono-sulph-anthraquinonate of soda. To detect whether thorough conversion into alizarine has taken place, a sample of the melt is dissolved in water, neutralized, and filtered ; the filtrate is shaken up with ether, which dissolves the alizarine and isopurpurine, whilst the sulph-anthraquinonic acid is retained by the water, and can be detected by the blue colour it gives with potash. An aqueous solution of the melt is heated with caustic lime, boiled, and filtered ; if the filtrate is orange, and deposits yellow flocks on the addition of an acid, oxyanthraquinone and anthraflavic acid are present. This will not only guide a manufacturer in its production, but forms a most useful test for its commercial value. One part of dibrom-anthraquinone is heated in an open vessel of enamelled iron or glass to 180-200 (356-392 F.) with 2-3 parts caustic potash, and sufficient water to dissolve the alkali ; the heating is continued until the mass acquires a deep-blue colour; when cool, it is dissolved in water and filtered ; from the filtrate, alizarine is precipitated by an organic acid ; the yellow flocks are collected in a filter, and well washed with water. Disulph-anthraquinonic acid is mixed with about twice its weight of caustic potash or soda, and heated at 180-210 (356-410 F.) till its aqueous solution gives a copious yellow precipitate on addition of hydrochloric acid. It is now dissolved in water, acidulated with sulphuric or other acid, to precipitate the colouring matter, which is filtered off, and washed with slightly acid water. 684 COCOA. From the yellow filtrate, colouring matter can be obtained by neutralizing with soda, and leaving it to settle, whe i it will form a dark-brown powder ; its solution may be precipitated with alumina to form pigments or lakes. Dinitro-anthraquinone is heated in a concentrated (sp. gr. 1-3 to I'-i) solution caustic soda or potash at 170-220 (388-428 F.) until the blueish-violet colour ceases to become more intense. The cooled mass is dissolved in boiling water, and filtered. The hot filtrate is treated with hydrochloric acid, which gives rise to a brownisii-yellow precipitate ; this, after it has been well washed, is r&idy for direct dyeing and printing. The residue on the filter consists principally of "regenerated" anthraquinone, which, by transformation into nitro-anthraquinone, becomes a furth< r source of colouring matter, from which pure alizarine can be obtained, by extraction with ether or other suitable solvent. Alizarine is sold iu the form of a yellowish-brown thick solution, or pasty fluid, containing 10, 15, or 20 per cent, of colour, and is sent out in wooden casks. Quite recently, methods have been discovered by which a product containing 80 per cent, of pure, perfectly soluble colouring matter can be obtained. Dry alizarine could be easily prepared ; but, owing to the difficulty of reducing it to a powder or paste again with water, the goods become spotted, and a larger quantity is consumed ; it is on this account also, that it contains rarely so much as 20 per cent, dry alizarine. It is used for dyeing violets, lilacs, and Turkey reds. The paste dissolves readily in caustic soda, yielding a splendid violet-blue solution. Pure alizarine can be obtained from this paste, by dissolving in weak caustic soda solution ; on adding chloride barium, and boiling, a dense precipitate is formed, which is filtered off and well washed with water ; it is then diffused in water, and decomposed with an acid, when the orange precipitate, after filtering, washing, and drying, consists of nearly pure alizarine. Kopp separates yellow alizarine from alizarine verte by dissolving in hydrocarbon and treating with alkali. Isopurpurine, Anthrapurpurine, or Yellow Alizarine. This is obtained from the alizarine prepared by Gessert Bros., by dissolving in ammonia, and adding hydrate baryta ; the precipitate is boiled in water, and the red liquid is filtered ; from this the isopurpurine is precipitated by an acid> filtered off, and washed, the process being repeated. If sulphuric acid is used, the isopurpurine is taken up with alcohol, from which it can be obtained in crystals. It is an orange-red substance with all the properties of alizarine, but it dissolves in soda with more of violet-red coloration ; in ammonia, it gives a reddish-brown colour. In dyeing, its shades of red are similar to alizarine, but purer ; the purples are more blue ; and the blacks, more intense. When used to dye Turkey-red, it produces a brilliant scarlet of remarkable permanence. Its alkaline solution gives a spectrum resembling that of alizarine. Perkin obtains it from crude alizarine, by the following process : The latter is first dissolved in water containing a little carbonate soda; the solution is shaken with recently precipitated alumina, which combines with the alizarine, settles as a lake, and is filtered off; the filtered liquid is heated with hydrochloric acid, and the colouring matter thus precipitated is filtered off, washed, and dried. It is further freed 1'rom anthraflavic acid, and other impurities, by repeated boiling with alcohol, digesting with a boiling solution of soda, and washing with the same. It is then dissolved in boiling water, and precipitated with chloride barium ; it is collected on a filter, washed with warm water, and decomposed by boiling with carbonate soda ; from this solution, when filtered, hydrochloric acid precipitates the anthrapurpurine. Caro (1876, No. 1229) obtains alizarine orange, by acting on commercial alizarine with nitrous acid. From this is obtained a material having the properties of purpurine, by dissolving it in 10 parts by weight sulphuric acid (sp. gr. 1-848), and heating to 150 (302 F.), until gases cease to be evolved, when the colouring matter is found in solution. On addition of water, it is precipitated. Bibliography G. W. Gesner, 'Coal, Petroleum, &c.' (New York: 1865); Reimann, 'Technologie des Anilins ' (Berlin : 1866) ; M. C. Knab, ' Etudes sur les Goudrons ' (Paris : 18G7) ; W. H. Perkin, 'Aniline or Coal-tar Colours' (Cantor Lectures, Society of Arts: 1869); Girard and De Laire, De'rive's de la Houille ' (Paris : 1872) ; Bolley and Kopp, ' Matures Colorantes ' (Ziirioh : 1873) ; W. Crookes, 'Wagner's Chemical Technology' (London: 1874); C. Schorlemmer, ' Carbon Compounds' (London : 1874) ; W. Crookes, ' Auerbach's Anthracene ' (London : 1877) ; E. J. Mills, ' De^truotive Distillation '(London: 1877); ' Chemical News ;' 'Journal of Gas-lighting; 'Specifications of Patents. R.L.N.F., T.T.P.B.W. COCOA, or CACAO. (Fu., Cacao ; GEB., Cacao ) This product is the fruit of the " Cocoa-" or " Chocolate-tree " (principally Theobroma Cacao), a tropical evergreen shrub, belonging to the order Byttneriacea. It is altogether distinct from the " Coco-" or " Coker-nut " (Cocos nucifera) see Nuts ; and from the " Coca " (Erythroxylon coca) see Narcotics. The husks of the fruit-pods of the cocoa-tree contain a number of seeds, very closely packed in a little pulp. The seeds, or " beans," after being dried, roasted, and ground, constitute " cocoa" ; if COCOA. 685 merely broken up after roasting, " cocoa-nibs " ; mixed with starch and very finely ground, "soluble cocoa" ; the same made up into a paste, and flavoured, "chocolate." (See Beverages Cocoa.) The pulp is commonly used for food and confectionery, and from it have also been prepared jellies, spirits, liqueurs, vinegar, &c. The pods also yield an oil, called " butter of cacao " (see Oils). The wood is porous and light, but capable of taking a Ligh polish. The tree is indigenous to tropical America, originating probably in Mexico : its height is 15-40 ft., seldom exceeding 1 7-18 ft. when under cultivation ; its range of altitude extends to nearly 2000 ft. ; it grows wild between lat. 17 N. and 17 S., but the cultivation has been extended 8 farther in both directions. Varieties. The following table will shew the principal species of Theobroma, their habitat, the commercial name of their produce, and the material in which the "beans" are packed for transport : Botanical Name. Where Gr own. Commercial Name. Packing. T. angustifolia. Mexico. Cotton or hempen sacking. T. bicolor. Brazil. Maranhan. Bahia. New Granada. Magdalena. T. Cacao (sativa). Australia. Bourbon. Matting. Ceylon. The name of each Cuba. country. Dominica. Guadaloupe. Guatemala. Central American. Guinea. African. Hayti. India. Barrels and sacking. Jamaica. Sacking. Java. Madagascar. Martinique. The name of each Barrels and sacking. Mauritius. country. Philippines. St. Croix. St. Lucia. St. Vincent. Trinidad. , Venezuela. Maracaibo. Caracas. Sacking. T. glauca. T. Guyanensis. Cayenne. Surinam. Berbice. Surinam. Barrels and sacking. Sacking. T. microcarpa. {Ecuador. ' Peru. Esmeralda. Guayaquil. Coarse sacking. T. ovalifolia. Mexico. Soconuzco. Hides." T. speciosa. Bnzil. Para. Sacking. T. sylvestris. Brazil. Jamaica. Besides the above-mentioned species, distinguished by botanists, T. Cacao, which is the most widely and largely cultivated, is divided by cocoa-planters into several varieties, the differences observed being mainly due to the long-continued influences of varied climates, soils, and modes of culture. The best of these is the "Creole ' (or Criollo of the Spanish inhabitants of America). The pods are small ; but the beans are thick, short, and almost globular, pale crimson in colour, and of slightly bitter, but agreeable, flavour, soft and oily. The beans require about three days for fermentation. This much-prized sort is become very scarce, chiefly through the bad policy of replacing decayed trees by inferior specimens. The next variety is the Forastero, the best kinds of which are the Cundeamar, of two descriptions, one with yellow, the other with red pods ; the former is the better, containing large seeds, which, in colour, and the ease with which they are fermented, resemble the Criollo. The third variety is the Amelonado ; and the fourth and lowest is the Calabacillo, whose seeds are small and very bitter, and of very dark crimson colour ; it has a very low market value, but many planters grow it, on account of its heavy yield ; it should be avoided on all new estates. All the varieties except the Criollo, which is probably confined to Venezuela, are known collectively as Trinitario or " Trinidad " ; they are drier and more bitter than the Criollo. The best of the Trinitario sorts are but little inferior to Criollo in the matter of quality, and are superior on the score of fruitfulness. Hence Trinidad forms the principal nursery whence plants 686 COCOA. or seeds are procured for the establishment of new plantations. The various descriptions of cocoa may be placed in about the following order of merit : Soconuzco (Mexico), and Esmeralda (Ecuador), all consumed at home; Caracas aud Puerto Cabello (Venezuela); Triuitario; Magdalena and Carthagena (New Granada) ; Para ; Bahia. Production and Consumption. A rough idea of the sources whence the principal supplies of cocoa are drawn may be gained from the following figures, which do not, however, refi-r to the same year in all cases, and are not, therefore, strictly comparative: Ecuador, 28,000,000 Ib. ; Trinidad, 11,000,000; Brazil, 7,000,000; Venezuela, 7,000,000; Grenada, 2,000,000; Mexico, 2,000,000; Martinique, 700,000; St. Vincent and Hayti, 550,000; Celebes, 250,000; St. Lucia, 250,000; Guadaloupe, 200,000; Dominica, 200,000; Cayenne, 65,000; Jamaica, 50,000. In 1878, the imports of cocoa into the United Kingdom amounted to more than 18,000,000 Ib., valued at 687,285^. ; more than half was enti-red for home consumption ; over 10,000,000 Ib. were contributed by the British West Indies. Cultivation. The climatic conditions of some countries necessitate certain modifications in the method of cultivation, which will be categorically alluded to presently ; the main points, however, in the culture of cocoa remain the same, and may be described once for all. Planting. The first care is to form a nursery for the young plants. This should be a choice patch of moist land, well cleared of weeds. The cocoa-seeds are carefully extracted from fine fully- ripe pods, and are sown 1 ft. apart, in furrows 2 in. deep, and are lightly covered with earth. Plantain-leaves are then spread over the ground, and left for about a fortnight, by which time the cocoa-plants should make their appearance. The ground is thoroughly weeded till the plants attain a height of 12-18 in , when they are taken up very carefully, and transplanted to the cocoa estate. The soil chosen for this purpose must be rich and flat, and convenient for irrigation. The trees thrive best on gentle slopes, facing away from prevailing cold winds. When the land has been cleared and burned, it is planted at intervals of 25-40 ft. with seeds or suckers of varieties of the coral-bean tree (Erythrina Corallodendron), called "shade," or " madre di cacao"; these grow to a great height, and afford the permanent shade required by the cocoa. This done, the young cocoa-trees are planted in regular lines, at about 12-30 ft. apart, the distance depending upon soil, climate, and the character of the species under cultivation. As the coral-bean trees do not imme- diately afford the necessary shade, coffee, plantains, and manioc are planted among the cocoa-trees for this purpose, until the coral-bean trees are sufficiently advanced, when the plantains and manioc are dispensed with, and the coffee only is left. In the second year, the cocoa-trees begin to put forth flowers, which are removed; at the third year, they require air, and no other crop must remain with them. Pruning and Weeding. One of the most important details of the cultivation is the proper pruning of the trees, so as to induce a trichotomous growth a straight, single stem, crowned by a well-formed head. The estate needs weeding at least twice a year, the weeds being chopped off with a cutlass, as hoeing is not required. Diseases and Enemies. The tree is sometimes attacked by a disease called mancha, which first destroys the roots, and quickly causes death ; it spreads so rapidly on an estate that thousands of trees are thus destroyed in a single night. The plant is also subject to several insect pests : ants prey upon the young leaves, boring grubs injure the bark, and the larvae of moths devour the matured beans. Wind is a great foe : whole plantations have been destroyed by one storm. Harvesting. The cocoa harvest takes place principally in June and December, the crops being known respectively as " St. John's," and " Christmas." In the tropics, however, the fruit continues to ripen throughout the year, on which account the trees are visited every fortnight, to gather any matured pods, and to prune where necessary. The pods are carefully selected, and are detached by a knife mounted on a pole; the stem must be cut clean through, without injuring the branch whence it springs. Women and children gather them into heaps, and convey them away for preparation. Production. Unless under exceptional circumstances, there should not be more than 900 trees to an acre. The average annual produce is estimated at 4-6 Ib. from each mature plant ; instances are recorded of an average of 11 Ib. a tree in one season, and 15 to 18 and even 20 Ib. from individual trees. The fruit is allowed to ripen at the 4th or 5th year ; but the crop is not plentiful until the 7th-10th year, after which the trees continue prolific for 15-40 years. The cultivation is considered profitable for large capitalists, or gardeners, as the plant requires less outlay and trouble, and yields a larger return, than perhaps any other tropical crop ; nevertheless, the risks from storms and the attacks of insects render it very uncertain. Preparation. The gathered pods, resembling gherkins in size and shape, and varying in colour from purple to lemon, are submitted to a process of " curing," which requires much experience and delicate skill, as upon it depends the preservation of the cocoa, and the development of its flavour. The essential objects of the curing are (1) fermentation, to reduce the glutinous, saccharine pulp surrounding the seeds, thereby giving tone to their colour, and modifying their flavour ; and (2) COCOA. 687 drying the fermented " beans," to ensure their keeping. The process admits of several modifica- tions, dependent upon the market for which the product is destined. The seeds are first carefully extracted from the pods, and placed to ferment. If for Europe, they are fermented in barrels, troughs, or heaps, covered by plantain leaves or by sacks, within the Si sweat-house," a closed chamber, exposed to the sun, and raised ou walls about 6 ft. above the ground. The sweating is best performed in deal boxes, 3 ft. long, 2 ft. wide, and 3 ft. deep, provided with covers, and holding about 500 Ib. raw beans ; the sides are perforated near the bottom, to admit of the cocoa draining. Here the seeds remain for 3-10 days, at a temperature of about 60 (140 F.), losing much water, and their bitter and astringent principle, becoming lighter, acquiring a mild, agree- able flavour and a fine cinnamon hue, and admitting of their easy separation from the husk by a slight pressure. The liquor which drains out in the process is often {hrown away, but may be utilized for the making of vinegar and spirits. They are then transferred to the " drying house,'' a wooden shed, provided with a movable roof, and thoroughly ventilated Here they are spread evenly on mats, or on a platform, after having been rubbed with a little red earth. Excessive- heat is avoided, and the beans are constantly stirred about, one attendant sufficing for a house 50-60 ft. long by 18 ft. wide. The beans remain here until perfectly dry, and should show no trace of mildew. They are then placed in bags. Efforts should be made towards effecting the drying under a glazed roof, with abundant ventilation, thus saving labour, preventing pilferage, and improving the colour of the product. Another mode of fermenting the beans is known as " claying." They are placed in holes or trenches in the ground, covered with clay or sand, and stirred at intervals, while great care is taken to prevent the fermentation proceeding too rapidly. When it has reached its proper point, the beans are dried as described. The fermentation process is apparently indispensable to the production of fine cocoa ; but it is attended with some risk in wet weather, when the beans are liable to blister. According to some authorities, the chief object in claying the beans is to preserve them ; but it seems to originate in the demands of fashion rather than in any real utility. The essential characteristics of good cocoa beans are clear, reddish-brown colour internally ; dry crispness, allowing the easy separation of the " nibs," or plates, from the kernel ; the nibs of a dull-purplish hue externally, with a glaucous purple-brown fracture, dissolving readily when chewed, and manifesting a slightly warm, astringent, full chocolate flavour. Cost of Production. The amount of labour required for the cultivation and preparation of any specific quantity of cocoa may be estimated from the basis that, on the average, 15-20 labourers suffice for each 30,000-40,000 trees, entailing an annual expenditure of about 200/.-240/. LOCAL VARIATIONS AND DETAILS. Those chiefly worthy of notice are the following : Africa. Some very fine cocoa has been sent from Monrovia, in Guinea, and fetched the highest price of any in the market. Bolivia. The cocoa growing on the banks of the Mamore is equal, if not superior, to Maravilla or Caracas, and may be exported in large quantities when the railway is sufficiently extended. At present, every trader to Para takes a full load of cocoa in hide seroons, and finds a ready sale for the article, as it is so much better than that grown in Brazil. Bourbon. In this island, there are about fifty acres under cocoa cultivation. The product is of good quality, being of the Caracas description ; it used to be grown in connection with coffee. Brazil. The plant is indigenous to the districts of Valencia, Camanu, and Ilheos, in the province of Para, and is very abundant in the neighbourhood of the Amazon, Madeira, and Salimoes rivers. Throughout large tracts the plant grows wild ; but its culture is steadily increasing. Near the Layes rapids, on the Madeira river, wild cocoa trees are exceptionally abundant, and produce fruit of very superior quality. It would need very little labour to organize an excellent plantation here. The chief supplies come from Para ; the cultivation is being extended also southwards to Bahia, and even to Kio Janeiro. The exports fluctuate greatly ; this is to be attributed chiefly to floods prevent- ing the harvest. The cultivation in this country is marked by great carelessness ; no nurseries are formed for the young plants, and the only shade provided appears to be that of bananas and plantains ; the ripe pods are knocked off the trees, and piled in heaps on the ground for fermenting; after 3-4 days, the pods are opened, and the extracted beans are spread to dry on the ground, or on mats. The dual harvests take place in December-January and May-June, the latter being the more abundant. The climate seems to be peculiarly suited to the tree, for in spite of severe floods, and careless culture, or no culture at all, it flourishes exceedingly, and continues prolific for 50-60 years. Cayenne. The extent of land under cocoa in Cayenne does not exceed about 650 acres, the exports, in 1874, being less than 600 cwt. The product is dried in the sun, or by currents of air, and has a softness of character which renders it valuable to mix with the drier, aromatic, Caracas growth, for purposes of chocolate manufacture. Ceylon. The culture in Ceylon has not hitherto been extended to such a degree as could be 688 COCOA. wished. Samples that have reached English markets have been reported as of very fair quality well-cured, and thin-skinned, and by no means common ; but, at the same time, not of the richest character, and not so carefully grown as they might be. Plantations, formed in parts of the island too hot for successful coffee-growing, have come on well, and importers are anticipating the development of this new source of supply, which will make them less dependent upon the Trans- Atlantic crops. The seeds were chosen from the best varieties grown in Trinidad, and, in 1874, more than 40,000 seeds and plants were distributed from the Botanic Gardens at Peradeniya. There will before long be a very large area of land under cocoa, in the warmer parts of the islaud. Costa Kica. The exports from San Jose' in 1878, were 5836 Ib. Ecuador. This state yields the greatest quantity of cocoa. The kind chiefly grown is Guayaquil, an inferior variety, costing only half as much as Caracas, and very largely consumed in Germany. A second variety, Esmeralda, is considered supeiior to Caracas, but it is confined to home consumption. Cocoa is the staple of the country ; but the crop of 1878 was the smallest on record, on account of continued rains. The exports from Guayaquil for 6 years, stated in quintals of 220 Ib., were, in 1873, 251,812; 1874, 250,216; 1875, 176,207; 1876, 224,739; 1877, 203,131; 1878, 98,765. The value in 1877 was 45*. a quintal; in 1878, 65s. The 1878 export was thus distributed: Continental Europe, 59,000 quintals; England, 20,714; United States, 7761; Central America and West Indies, 7000; South America, &c., 4200. Guatemala. The cocoa export of 1878 was only 2300 Ib. ; valued at 1 dol. a Ib., and all sent to Central America. Honduras. The Soconuzco variety, which, during the Spanish occupation of Mexico, was reserved for the Court of Madrid, is said to grow wild here, with fruit measuring 2-2 in. thick, and 6 in. long. When cultivated, the dimensions increase to 3-3 in. x 8 in., and the trees bear in 6-7 years. India. The Indian Government has raised large numbers of seedlings, in Botanical Gardens, for distribution throughout the peninsula. The plants have been put out in the Neilgherry Hills, and in the Terai, and have been found to grow well while looked after. The tree has been very successfully reared in Coorg ; the plants are grown from seed in nurseries, and transplanted, when 18 in. high, into large pits, 12 ft. apart. Malay Archipelago. The cocoa tree was introduced here by the Spaniards, more than three centuries ago. In 1854, Celebes produced nearly 200,000 Ib., which figure has since increased. The yield averages 5-6 Ib. a tree. Small quantities of Java cocoa have occasionally appeared at London sales, and elicited similar opinions to those expressed on Ceylon produce. In the Philip- pines, cocoa is commonly grown for local consumption. The trees, which here attain but very dwarfed stature, are commonly found in the gardens, planted very closely, in order to keep down weeds. Instead of a nursery for rearing the young plants, the natives cover the kernels, when they begin to sprout, with a little earth, and place them in spirally rolled leaves, which are hung beneath the roofs of dwellings till the plants are ready for putting out. The best cocoa is produced in the small island of Maripipi, and never comes to market ; the next best is tl Albay growth, which is reckoned equal to Caracas ; the samples produced in Cebu and Negros are fairly good, but in trifling quantity ; BO that these islands have to import from their neighbours, Ternate and Mindanao. It thrives as well in the Spice Islands as in Mexico, and is supplanting the less profitable clove-tree. Nicaragua. Several important plantations have recently been commenced here by Frenchmen. Peru. Besides being cultivated in all the gardens of the Montana, cocoa grows spontaneously and abundantly in the forests of that province. The exports from Mollendo, the chief port, in 1878, were but 1500 Ib. Surinam. The cultivation here has been considerably extended of late years, the estates being worked hitherto mostly by Creole labourers ; but these have proved so unreliable, that coolies have been substituted. The severe drought of 1877 injured the plantations in an extraordinary degree. The production was, in 1875, 1,322,811 kilos.; 1876, 1,322,674 kilos. Venezuela. The cocoas of Venezuela, known as Caracas, and Maracaibo, are considered the best of all produced in the western hemisphere, and though the bean was first imported to Spain from Mexico, it has subsequently been largely exported to the latter country from Venezuela. In this country, the tree is said to thrive best in damp, level soil, and bears about 1 Ib. of fruit at the fifth or sixth year ; near the sea-coast, it is in full bearing at the eighth year, but in the Guique districts on the Lake of Valencia, and in the province of Carabobo, it is not matured till a year later. Experienced planters state, however, that it should cover all expenses from its sixth year. The quality of the Venezuelan cocoa has been greatly spoilt by the introduction of the much more prolific but very inferior Trinitario, or " Trinidad," beans. The latter is now the staple product from the district of Giiiria, Maturin, Carupano, and down the coast as far as the Rio Chico; but the Criollo, or " Creole," plant is still cultivated upon some few estates. The Trinitario seed is also sown, to some extent, in the valleys of the Tuy, although the majority of the estates there are COCOA. 689 sown with Criollo seed, and good cocoa can still be procured thence. From the port of La Guayra westward towards Puerto Cabello, and particularly at Ghoroni, O'Cumar. Turiamo, Patanemo and Borburato, lie the districts yielding the best produce, the choicest of all being from the estate of (Jlmao near Ghoroni. From the neighbourhood of San Felipe, the capital of the state of Yaracuy, a very superior mixed cocoa is exported, to the amount of about 4000-0000 cwt. annually. The Trinidad seed has, since 1854, been introduced into Chichiriviche, formerly oue-of the finest cocoa districts. Many plantations were damaged, and some entirely destroyed, by the great drought of 1868-69. On some of the Caracas estates, where Trinidad cocoa has been introduced, the produce has fallen into great disrepute, and some of the planters import the red soil of Ghoroni with which to colour the beans. The finest Venezuelan cocoas sent to Europe are the Puerto- Cabello and the Caracas varieties ; the latter, which is the dearest and best, is of four kinds, Chuao, Ghoroni, O'Cumar, and Rio Chico. In the matter of cocoa production, one of its richest and most valuable crops, Venezuela seems to be now scarcely as advanced as it was a century ago ; not only has the quality of the product deteriorated, by reason of the substitution of Trinidad for native seed, but the quantity has also fallen off. The best brands now exported are absorbed by Spain and France. They are grown almost solely in the coast districts, and hence are called Cacao de la costa ; the beans are full-coloured, and larger, richer, and more oily than other sorts The so-called " mixed cocoa " (Cacao mezelado) is the produce of estates where the native and Trinidad seeds have been sown indiscriminately ; it is much inferior to the preceding, though the foreign trees have greatly improved in the more favourable soil ; the produce goes chiefly to England and Germany. A third quality is the fruit of the Trinidad tree alone. The relative prices of the qualities on the spot 'n approximately H.-81., 4/.-5/., and 21. 8s.-3/. 12s. a cwt. The flavour of cocoa depends principally upon the soil ; the finest Venezuelan cocoa all comes from one estate, and though the seed has been tried within a mile of the spot, no such quality can be produced. It is never exported, as it fetches twice as high a price iu the country as it does in Europe. There is no doubt that the soil and climate of Venezuela are eminently fitted for this branch of agriculture. The land lies low, being subject to inundation, and retaining its moisture in the height of summer. The climate is hot, but at the same time very humid. The trouble and expense of irrigation are thus avoided, without any detriment to the crop. The ground is prepared in the months of January-March, before the commencement of the winter rains in April-May, when the bananas and the "shade" plants, locally termed bucare (Erythrina umbrosa, and E. velutina), are planted. When laying out good virgin soil with " Creole " plants, it is usual to place one at each angle of a space 12J ft. square. In poorer land, this distance is reduced a proceeding based entirely on false economical grounds. An important operation in this climate is the provision of trenches between the rows, in order to carry off the excess of water during heavy rains, as nothing is so injurious to the health of the tree as stagnant water. This draining forms one of the chief items in the cost of the cultivation. Between the appearance and the ripening of the fruit, there is an interval of nine months. The average yield is 1-1 J Ib. from each tree. The life of the tree is reckoned at 35-40 years on good soil, 20-25 only on poorer land. The pods vary in size and shape. The so-called " cows' -tongues," 9 in. or more long, are preferred, because the husk is thinner and the pod contains more beans ; more commonly the pods are shorter and rounder, but larger, and are called " angolitas." In dry weather, a single night will suffice fur the fermentation ; but in wet weather, the beans may be left for two or three days without inconvenience. They are then dried in the open air, exposed to the sun, in a courtyard or on drying frames; 8-10 hours of sun is generally enough ; they are housed at noon when the sun is at the hottest ; and are left in the store for a day or two to complete the drying. Some groweis dry the beans on large sheets, which can be readily housed in case of rain. The above remarks refer especially to the "creole" plants, which were formerly so much grown, and whose produce was so highly esteemed. This is now largely replaced by the Trinidad variety, whose violet-tinted, sharp and bitter-flavoured beans are made to assume the colour, odour and flavour of the " creole " cocoa, by prolonging the fermentation to four days or more, and by the application of red earth, brick-dust, and vermilion. West Indies. The best months for pruning, in the West Indies, are March-April ; but large branches may be trimmed in August-September, should there be no young fruit to sacrifice. The tree does not thrive where exposed to easterly and northerly winds. Dominica. The cultivation here, though established some thirty years, is still but little developed. The trees have been crowded together at intervals of only 2-4 ft., with the effect of choking each other for lack of room ; and pruning seems to have been systematically neglected. No attempt has been made to provide shade, as in Trinidad and Venezuela, but the cocoa has been rather planted to afford shade to coffee. Shade and shelter would doubtless be needed by the more delicate Trinidad varieties in sunny spots. Care is not taken in the fermentation and claying of 2 Y 690 COCOA. the beans. The produce is shipped to Barbadoes and Martinique, partly for local consumption, and partly for re-shipment to England, France, and America. Au export duty of 13%d. a cwt. ia charged. Grenada. There are at least 4000 acres under cocoa in this island. The export duty is 6d. a cwt. Guadaloupe. After much neglect, attention is again being directed to the cultivation here, the plantations being formed with trees imported direct from Venezuela. Jamaica. Two centuries since, the produce, in exceptional years, was reckoned at 20 Ib. a tree, and averaged 8 Ib. a tree, at 18 ft. apart, in fairly good soil. The import duty, then placed on cocoa by the British Government, crushed the industry ; under the present more favourable conditions, however, efforts are being made to resuscitate it. Martinique. Owing to the disastrous failure of the crop many years since, cocoa cultivation was long discontinued here ; lately, however, it has been resumed and extended, and the produce is of good quality. St. Domingo. The exports were, in 1878, to France, 17,200 Ib.; West Indies, 6000; Italy, 4800; United States, 1600. St. Lucia. This island has about 450 acres under cocoa ; the exports are almost stationary. St. Vincent. The export duty here is 8d. a cwt. Trinidad. Cocoa is the second great staple of production. The high cultivation bestowed upon the native seed has greatly improved it, so that in some districts it is almost to be compared with the ' creole " of Venezuela. A recent writer from the island says the trees yield 15 Ib., and in very good years, 18 Ib., clean, dry cocoa at a crop ; but the average yield of the best estates is about 2 Ib. a tree per annum, which, at 12 ft. apart, gives 600 Ib. an acre. The average of the whole island is 500 Ib. an acre. The best qualities fetch 6/.-7/. a cwt. ; the inferior, about half as much. The export duty is llfd a cwt. The shipments for the last four years have been as follows: 1876, 8.706,500 Ib.; 1877, 8,103,779; 1878, 9,392,324 ; 1879, 11,791,032. General Considerations. The points essential to success in cocoa cultivation are ; 1, Judicious selection of seeds; 2, Careful attention to pruning and draining; 3, Plucking the pods at the right stage ; 4, Nicely regulating the fermentation ; 5, Subjecting the beans to complete desiccation ; this is, perhaps, the most important consideration of all : they should rattle distinctly on being dis- turbed ; 6, Hand pic-king the dried beans, so as to eliminate leaves, stems, and other rubbish, which greatly lower the value of the sample ; 7, packing while thoroughly dry, in double sacks, or sound barrels (not hogsheads). Steamer transport is adopted wherever available, the advanced cost being more than compensated for by the higher price realized, by reason of the superior condition attained under shortened transit The consumption of cocoa is constantly increasing, especially in Latin Europe, and there is no reason to fear over-production for many years to come. In the autumn of 1878, the prices of cocoa advanced 25-75 per cent, according to quality, owing to the failure of the Ecuador crop. The duties on cocoa importations into the United Kingdom are as follows ; Cocoa, Id. a Ib. . husks and shells, 2s. a cwt. ; paste or chocolate, 2rf. a Ib. The price of cocoa now varies between 71s. and 108s. a cwt., according to quality. The following shows the relative prices (in shillings per cwt.) of the principa brands brought into the home market in 1878 and 1879: Trinidad sup., 120-5, 91-108; mid to fine red, 116-9, 81-90; grey and mixed red, 114-5, 75-80. Grenada 110-4, 78-86. iJominica and St. Lucia 110-2,72-8. Surinam 116-9, 80-90. Caracas 116-123, 85-105. Para 115-20. Bahii 115-20. Guayaquil 112-130, 71-90. The Guayaquil and Caracas varieties find the readiest market on the Continent, where they are used chiefly for chocolate manufacture; the Colonial descriptions Trinidad, Grenada, Dominica, &c. take the lead in the home market ; Bahia, Surinam, &c., are pretty equally distributed. The consumption in this country is now calculated at about 0-3 Ib. per head of population. The total imports were, in 1874, about 18 million Ib. ; 1875, 16 million ; 1876, 20J million; 1877, 17 million; 1878, 18 million. The imports in 1878 were contributed as follows : British West Indies, 10,434,608 Ib. ; Brazil, 2,518,703; Ecuador, 1,655,867; San Domingo, 792,602; France, 743,659; Holland, 563,558; Germany, 288,705; British Guiana, 276,533; West Coast Africa (foreign), 185,197; Venezuela, 149,845; Surinam, 106,256; United States, 35,903; other countries, 270,190. Guarana. A substance which, though not a cocoa, yet bears in many respects a close resem- blance to that product, is guarana, a so-called " bread," yielded by the Paullinia sorbilis, a plant of he order Sapindacece. It is a native of Brazil, and grows abundantly in the province of Amazonas, along the banks of the rivers Tapagos, Kio Negro, &c., as well as in Guiana and Venezuela. The genus, indeed, is a large one, and it is probable that the seeds of P. Cupana of the Orinoco, as well as those of many of other species, may be used for alimentary purposes. Guarana is manufactured by the Muras, Mondrucas, and other tribes of Indians, and is much esteemed, both as a food and as a medicine, throughout Guatemala, Costa Rica, Brazil, and other parts of South America. COFFEE. 691 The preparation is conducted in the following manner : The fruit, whick is scarcely as large as a waluut, is gathered when ripe, and roasted intact. Its seeds, numbering about half a dozen, are then taken out, and, after being pounded between stones or mallets, are formed into a thick paste with water, and moulded into cakes and rolls of various forms. These are dried in the sun, or by the fire, by which they become extremely solid and difficult of fracture, and will keep good for any length of time. For use, the rolls are grated to powder, which is very like cocoa in appearance, or they are ground in water, and sweetened ; the beverage thus produced is analogous iu its effects to tea and coffee. The city of Santarem annually exports about 16,000 Ib. of guarana, valued ut 8d. or 9d a Ib. at the port, but selling for very much less in the neighbourhood of its production. It figures among the non-officinal substances of the United States Dispensatory. In Europe, it is but little known as yet; it is included in the French Pharmaceutical Coe flourishing, had the forest shade been at least partially retained. The history of coffee cultivation in the East proves that, in hot climates, and where prolonged seasons of drought may recur, coffee will nut flourish permanently, except under shade. In a state of nature, the plant almost universally affects shade ; this is the more remarkable^ that the seeds are deposited by wild animals and birds as freely on open grass lands as in forests. A suspicion that the borer, leaf-disease, and other immediate causes of decay, are only induced by the weakened state of the shrubs, consequent upon their exposure to lengthened periods of drought, is supported by the fact that where shade trees are found standing upon an abandoned estate, they are surrounded by a surviving remnant of coffee bushes. The question as to where shade is necessary is one of climate ; it is not universally beneficial. The advantages to be derived from it, in very hot climates, are : Diminished exhaustion, and consequently increased longevity of the plant ; reduced cost of cultivation ; a conservation of the nutritious properties of the soil, and an actual increase of them, as the cover given to the ground causes the surface vegetable matter to decay more rapidly ; and, provided the tree be a sub-soil feeder, the shedding of its leaves will yield a positive gain of surface matter, which the roots of the coffee would otherwise never have reached. In addition to this, there is the direct value of the timber grown. The only drawback to shade would seem to be a diminished yield of coffee ; but this is atoned for by the increased longevity of the plant. The most suitable trees for affording shade will be alluded to under the local headings. Roads. Efficient roads not only greatly facilitate the working of a plantation, but they should be so laid out as to serve the additional purpose of drainage. A cart road should pass through the centre of the estate, wherever it is possible to avoid a steeper gradient than 1 in 15, emerging upon the main highway. From this, branch roads should be cut at right angles, with as easy gradients as possible, and not more than 100-150 ft. apart. These branch roads should cross the lay of the ground, so as to check, to the fullest extent, the effects of waste. A boundary path encircling the estate is useful for many reasons. The main central road should be set out before pitting and planting. Wire tramways commend themselves as eminently suited to minimize labour on coffee estates. An excess of road accommodation, as regards both the number and the width of the paths, is far preferable to insufficient reading, despite the extra first outlay. If the ground be rich, it may cost a good deal to keep the roads clean and free from weeds. This, however, may be greatly lessened by ploughing them up and planting them with an annual crop, until the land is exhausted ; not only will the roads be rounded by the ploughing, but weeds will not so readily grow. Drains. Nothing is more important than the thorough draining of a coffee estate, in order to carry away the excess of moisture during heavy rains, without allowing the surface soil to be washed away. Continuous open trenches are cut in parallel lines across the face of the slope, and at 10-15 yards apart ; their gradient should never exceed 1 in 12, and 1 in 20, or even 30, will be better ; their width may be 15-18 in. ; and their depth, not less than 1 ft. at the lower side. They need constant cleaning out and repair, especially after a heavy shower. They must in all cases empty into a natural or artificial channel amply capable of carrying off the water ; if furnished with breaks to catch the suspended soil, so much the better, as the latter can then be collected and returned to the estate as a dressing. Catch-Crops. Much has been said both for and against the growing of other crops among the coffee shrubs. In the West Indies, the culture of plantains, yams, cocoa, &c. was carried to such an extreme that the coffee became, in fact, of secondary importance, or was even killed out. In Ceylon, too, catch-crops were long in vogue ; but they seem now to have gone out of fashion, as they exhausted the soil, and produced too much shade. There is nothing to object to in the simultaneous cultivation of several crops so long as each has due space, and sufficient manure, and the plants are not antagonistic to each other, as the failure of one crop may be compensated for by the success of another. Bice and tobacco have been found to yield good returns as catch-crops 696 COFFEE. but they possess a disadvantage in not affording any shade to the young coffee plants. Cocoa, yams, and plantains are, perhaps, even less advisable ; , and similar attempts with cotton have proved altogether failures. Maize, on the other hand, is highly spoken of by Stainbank, from experiences in Natal. It should be planted thinly in three rows, 18 in. apart, between the coffee rows, and two plants in the coffee rows between the coffee plants. The seed should be sown immediately after the coffee is planted. It grows very quickly, and should early be thinned out to 18 in. apart in the rows; it will soon be high enough to completely shelter and partially shade the coffee, which will grow all the faster in consequence. The latter will also be benefited by the extra working of the ground. In the autumn, a dressing of manure is applied, and the ground is ploughed, or deeply hoed, preferably the former. The crop may be repeated in the following spring, reducing it, however, to two rows and one plant, and repeating the manuring and ploughing r hoeing; this time the choice between plough and~hoe will be governed by the size of the coffee shrubs ; the same manure will suit both coffee and maize. Weeding. By " weeding," is meant the eradication of every plant which is not being inten- tionally cultivated. The operation is performed in different wayl, according to the nature of the soil. On light soils, and sloping situations, hand weeding is much the best. The labourer is provided with a pointed stick, to help in getting up obstinate roots, and carries at his waist a small bag, into which the weeds are at once thrust. They are turned out of the bags into pits dug at convenient intervals, or are heaped up in the road's, and are finally buried or burned, the latter being the surer way to destroy them. By weeding early, and repeating as often as necessary, the ground may be kept clean by hand. When hand weeding will not suffice, recourse must be had to " scraping " the ground, which is attended with a serious drawback, viz, : that the first inch or more of the best surface mould is removed at the same time, thus robbing the plants of food, and exposing the earth to the full effects ofwash. On stiff clay soils, on lovel plantations, and in damp, cool climates, on tlie other hand, hoeing is not only necessary for the perfect eradication of the weeds, but is of itself exceedingly beneficial to the soil, and, except during the dry season, should be regularly done whether weeds are present or not. When scraping or hoeing, it is imperative that the operation should be conducted from the outside towards the tree, so that the roots may be kept well covered, and the wash may easily escape into the gutters. Pruning. The kind of pruning first required by coffee bushes is that known as "topping." The age and height at which this operation is performed, depend in a great measure upon local circumstances ; the question is also a much debated one. The object of u topping," or removing the top of the bush, is to restrain its upward growth within convenient limits, and, as a natural consequence, to strengthen and concentrate its lateral growth. According to Sabonadiere, topping is commenced, in Ceylon, at the age of 12-18 months, the maximum ordinary height being 4 ft., t-ometimes reduced to 2 ft. He prefers to postpone the operation till the shrubs have borne the maiden crop, even though extra staking is required to withstand the wind. His plan is to remove the two primaries at the required height, by a sloping outward cut close to the stem, and then to remove the top by an oblique cut, BO that the stumps resemble a cross, and a firm natural knot remains to guard against the stem splitting down. Hull (Ceylon) contends that the plants should be topped as soon as they have reached the required height, when the soft wood is easily severed by a pinch between the finger and thumb. In Natal, the shrubs are topped either at their full height 4 J- 5 ft. or at 3ft, allowing a sucker to grow up on the weather side to complete the height. The latter plan is preferred. There is much advantage gained in limiting the height to 5 ft., not only is the crop gathered more easily and without damage to the tree, but it is actually heavier, and the shrubs are more readily made to cover the ground. The first result of topping is to induce the growth of a number of shoots, the removal of which is termed " handling " or " searching." The first to appear are vertical suckers or "gormandizers," from under the primary boughs; these are immediately rubbed off without injuring the bark. From the primaries, spring secondary branches, in pairs, and at very short intervals. All such appearing within 6 in. of the main stem are removed at once, so that a passage of at least a foot is left in the centre of the tree, for the admission of air and sun. The object of pruning is to divert the energies of the tree from forming wood, and to concentrate them upon forming fruit. The fruit of the coffee tree is borne by young wood ; and, as the secondaries are reproduced when removed, they are cut off as soon as they have borne, and a constant succession of young wood is thus secured. In order that this may be regular, and to avoid weakening the shrub, the secondaries that grow outside of the foot space are left on alternate sides of the primary, tlieir opposites being removed each year in turn; thus one is growing while the other is bearing. The one point in view must be the equal development of the tree, and the yearly growth of as much as it. will bear, but no more. Branches must not be allowed to grow into or cross each other ; if two m more secondnried spring from one spot, the strongest only must be retained ; where a gap occurs, tortinries mny be trained to fill it, in the same way. When practicable, the bushes should be handled twice before the crop; and the pruning sh'uilcl be commenced immediately after the crop, COFFEE. 697 and finished before the blossom comes out. Should that be impossible, it must be suspended during the 3 or 4 days of blossom time, and then be carried to completion. When it is evident that the crop on a tree will exhaust it if allowed to mature, a portion of it must be sacrificed by pruning. The loss thus occasioned is more apparent than real. In very prolific seasons, much fruit is wasted for lack of labour, and the trees are unnecessarily overtaxed, and bear poorly for some time afterwards. Everything should be done to ensure regular and even crops. The cuttings should be trenched in as manure. No branch should be allowed to bear more than two or three crops before removal. Regular and systematic pruning is one of the first essentials to successful coffee culture ; where plantations nave "been neglected on this score, they must be very gradually reduced to proper condition, by sawing out the cross branches, and opening up the centre of the trees, in the first year; and thinning out about h?lf the remaining wood, in the second year. Manuring. It is commonly taid that coffee is an unusually exhaustive crop; but the exhaustion of the soil consequent upon coffee culture is a result of the peculiar conditions under which it is prosecuted, rather than of the nature of the plant itself. Better than any amount of artificial manuring, is the retention of the naturally rich surface soil, by the effective prevention of wash. As a secondary adjunct, however, judicious manuring will be highlj beneficial, and even necessary in almost all cases after the first year or two. It is impossible to lay down any hard and fast rule for manuring; the most that can be done is to indicate the essential elements of coffee soils, the best artificial substitutes, and the best method of applying these substitutes. The best coffee soils appear to contain about 15 per cent, of combined iron, and alumina : the iron, if as red oxide, may amount to 20 or even 30 per cent., being a good absorbent of fertilizing constituents; but the alumina should not exceed 10 per cent. Lime is an essential, which must be supplied if wanting; this is too often overlooked, in the anxiety to furnish stimulants. The percentage of organic matter may be too high; it should represent about 0'2 to 0'3 per cent, of nitrogen. The best average manure for supplying nitrogen and potash is well-rotted dung ; but its frequent application should be accompanied by a little lime, unless the soil is already very rich in that constituent ; without the presence of lime, the shrubs will not receive the full benefit of the nitrogenous principles, but its use in a tropical climate must be governed by caution. Thoroughly fermented coffee pulp is a useful manure; but it is only half as valuable as dung, and costs more to apply. It should be kept covered as it is produced, and is best mixed with fermenting dung, failing which, it should be well limed. Alone, it is of small benefit ; but forms a good vehicle for concentrated fertilizers. Almost all soils require a constant renewal of phosphoric acid and lime, which are not supplied by dung alone. These constituents are best furnished in the form of bones (steamed and ground), or concentrated superphosphate (containing 40-45 per cent, soluble phosphate of lime). Nitrogenous manures alone are too stimulating, and help to produce premature exhaustion, therefore bones may with great advantage be added to dung. Composts of pulp and cake are useful nitrogenous manures ; but they must be accompanied by phosphates and lime. Potash seldom requires to be directly applied ; but is advantageous after attacks of leaf disease. Magnesia seems to be a necessary constituent (from 0'5 to 2-0 per cent.) of all good coffee soils; when wanting, dolomite may be applied. The great object of manuring is to supply all the constituents required, and in an available form. For coffee, the nitrogen is better applied in an insoluble form (as in dung, fish-manure, or cake\ than in a soluble form (as in guano, sulphate of ammonia, or nitrate of soda). Phosphates are best conveyed in bones, when a lasting effect is required ; but high class superphosphates are preferable for immediate effect, as in cases of leaf disease. In tropical climates, all manures are best applied frequently and in small quantities. Regular manuring after each crop would doubtless be most generally economical and advantageous. The quantity must depend on local conditions, but should always be extra liberal after a full harvest. Artificial manures should be put out only in damp weather ; dung may be applied at any time. The lime must never be in a caustic state ; its best forms are gas lime and gypsum. The manner of applying manures is not the same in all cases. No manure should be put more than 1 ft. below the surface of the ground, nor less than 18 in. from the stem of the coffee bush. On flat land, where there is no danger of wash, the manure may be spread over the surface, and hoed in to a depth of 9-12 in., or a square hole may be cut between each four shrubs, and the manure buried in it. On slopes, it is usual to dig a hole above each bush. For bulky manures, it may be 2 ft. long. 1^ ft. wide, and 1 ft. deep ; for concentrated manures, its dimensions will be reduced. The holes should be filled up with any prunings or other vegetable matter at hand, and covered down firmly with the loose top soil ; the new earth from the hole should be spread around the stem of the neighbouring tree to protect its roots. Ordinary manuring is sometimes supplemented by other methods of improving the soil. One of these is to loosen it, by driving a long bar or a manure fork deeply into the ground, and then prizing up the earth, without turning it over. A second operation is that known as " mulching," or " ground thatching," which consists in covering the ground under the bushes with a layer, 6-9 in. thick, of hard long grass. The effect of this in cold, wet soils, is to keep the ground warm, and 698 COFFEE. to throw off excessive moisture ; in hot, dry situations, it is equally useful to retain moisture. In any case, weeds are*kept down, and wash is quite prevented. When rotten, the grass may be hoed or dug in as manure. This thatching has been found a perfect cure for black bug. A third operation is called " trenching," or " waterholing." The trendies are made across the slope, and maybe either open or closed. In the former case, holes, 3-4 ft. long, 12-15 in. broad, and 15-18 in. deep, are cut between each four trees , the soil taken from them is spread over the roots of the trees, while the holes are left open to act as catch-drains, and as receptacles for wash, weeds, prunings, and other vegetable matters, being emptied twice a year, nnd their contents spread around the roots of the shrubs. Closed trenches are ditches cut across the entire length of the coffee rows* 2 ft. wide and deep, and filled with any vegetable rubbish ut hand ; they are then covered with earth, and well trodden down, while ilie remaining soil is spread under the trees. The benefit of trenching is greatest in stiff soils. The refuse matter in the trenches should be limed, to kill grubs and other vermin for which it will form a nursery. Diseases and enemies. Besides peculiar conditions of climate, aspect, drainage, shade, shelter, &c., already alluded to, particular attention must be paid to the prevention or cure of certain maladies to which the coffee shrub is specially liable. The number of these iusectifonn and fungoid pests is considerable ; but the only ones of sufficient importance to merit description are leaf-blight, fly, borer, bug, and canker. 1. Leaf-blight. The leaf-blight of Ceylon and Southern India was first noticed in the former country about 1869, and in India two years later ; by 1875, it had devastated whole districts, and since then it has been found in Sumatra and Java. Its existence at a distance from the Indian Ocean has not yet been proved, though there is some suspicion that an allied disease is indigenous to Western Africa. It is a fungus, known as Hemileia Vastatrix, and allied to the moulds. It is present in some form or other all the year round, and first attacks the under side of the leaves, causing spots or blotches, at first yellow, but subsequently turning black. These blotches are covered with a pale orange-coloured dust or powder, which easily rubs off ; they gradually increase in size, until at last they have spread over the leaves, which then drop off, leaving the trees unable to produce crop, or to bring to maturity that which may have already been produced. In districts affected by the south-west monsoon, during December to February, the fungus generally exists as an external parasite, in the form of long filamentous threads, covering every part of the bark and leaves, but so minute as to be invisible to the naked eye. The disease was made the subject of an official inquiry, by Daniel Morris, of the Peradineya Botanic Gardens, from whose report it appears that a successful mode of treatment has been found. Of the many materials experimented with, one only is invariably effective, viz. a mixture of best quality flowers of sulphur with caustic lime, in the proportions of 1 part (by weight or measure) of the former with three parts of the latter 1 '. 2 gives much better results at increased cost and thoroughly incorpo- rating them before use. When small areas only are to be treated, sulphur blowers may be used for applying the powder ; but it can be as effectively spread by hand, taking care that it is thrown upwards into the tree, and that the stem and branches become well coated. Sufficient will generally fall to the ground to disinfect the vegetable matter lying there; but under large and leafy bushes, a few extra handfuls may be sprinkled. This will especially apply when " mulching," or open trenching, is carried on. When once the mycelium, or vegetative part of the fungus, has penetrated the tissues of the leaves, no remedy can be used which will not also destroy the leaf. The only opportunity for combating the disease is while it is in the invisible filamentous state, on the exterior of the bark and leaves. At this time (December to February), each tree should be treated with about 5 oz. of the mixture, not omitting to disinfect the ground and whatever encumbers it. It has been observed that the treatment produces marked beneficial effects upon the trees in other ways ; their appearance becomes more vigorous and healthy, the foliage improves in texture and colour, the wood matures and bears earlier, the blossom sets better, and the crop is heavier. The measure is preventive only. The disease being infectious, and the spores of the fungus easily distributed by wind, every precaution should be taken to eradicate it from aban- doned coffee patches, and stray w.ld trees. Such had better be burnt, and the ground occupied by other produce. The cost per acre of the treatment is estimated as follows : Flowers of sulphur, 1 cwt., R. 10 ; coral lime, 3 cwt., R. 5 '25 ; hand spreading, E. T25 ; total, R. 16'nO. In hardly any case would it exceed R. 18-20 an acre, without transport. A disease known as " leaf-rot,'' rather prevalent in Mysore, is distinguished from the above, and is referred to a fungus named Pfllicularia Koleroga, by Dr. M. C. Cooke. It appears about July, when the leaves of affected shrubs become covered with slimy, gelatinous matter, turn blark, nnd drop off; clusters of berries also rot and fall. There is every probability that the sulphur and lime treatment would be effective in this case also. The shed leaves and fruit should be collected and burned. Fly. This disease has been known for many years in Dominica and Brazil ; it has also spread to Venezuela, the Antilles, Porto Rico, Martinique, Trinidad, and all down the Atlantic coast of COFFEE. 699 South America. It is caused by the larvae of a moth, scarcely in. long, named Cemiostoma coffeelum. The colour of the insect is dull-white or pale-grey, with a bar of black across the posterior end when quiet ; its motions are very active, and it readily takes alarm. The female is either provided with an ovipositor of sufficient strength to pierce the cuticle of tlie leaf, beneath which the egg is deposited, or it deposits the egg in some irregularity on the surface of the leaf, leaving the future caterpillar to find its own way into the tissue. In either case, a caterpillar develops from the egg, and feeds on the cell tissue of the leaf, in all directions, between the two cuticles. The insect prefers young and delicate leaves, and is most active alwut the commence- ment of the wet season, when, doubtless, the majority of the eggs are deposited. It is dormant during the wet season say from March to May Of the varieties of coffee met with in Deminica, the mocha is most subject to the attacks of this moth, its leaves being the most delicate. Stronger leaved varieties, when fairly healthy, are scarcely attacked ; but when existing under unfavourable conditions, such as to induce flaccidity of texture, they are sometimes much affected. The disease manifests itself by the appearance of large discoloured blotches on the leaves, causing their decay and fall. It has been stated that, by picking the leaves at such a, time as to take the greatest number of the larvae when about two weeks old, it would be easy to destroy the pest, as the size of the blotches would then easily distinguish the diseased fuliage. The insect is very susceptible to the effects of wood smoke, and may easily be driven off or destroyed by the smoke of ordinary wood or grass fires. At present it does not exiet in the West Indies to such an extent as to injuriously affect the fruitfulness of the trees, and is markedly less numerous where insectivorous birds abound. Borer. This pest, formerly known as the "worm"' and "coffee-fly," is most troublesome in Southern India, especially in Coorg and the Wynaad, where, in 1865-6, it destroyed whole estates. Beetles with similar boring habits infest the coffee bushes on the West Coast of Africa, and in Zan- zibar, and are occasionally troublesome in Jamaica. The Indian borer has been identified as the Xylo- trechus quadrupes. In its complete stage, the insect appears as a winged beetle ; it is-J to f in. in length ; rather finer in shape than a wasp; with a hard, shiay coat ; in colour, red and black, or, in other cases, yellow and black, in alternate transverse lines. It bores a passage into the stem of the coffee- tree, usually at some few inches above the ground. This passage, at first horizontal, soon takes an upward spiral direction, and proceeds until a safe retreat is found, in which the larva may be deposited. The tree soon droops, and dies down to the point at which the entry has been effected, and where it can be easily broken off by a sharp pull at the upper part. The only course is to break off the tree in this manner, and then to burn the stem, with the larva secreted in its centre. Young shoots will proceed from the stump (if the perforation has not begun too near the roots), and one of these may be trained to succeed the original stem. There is a growing impression that the borer can be kept out of estates in hot, dry situations only by providing bhade, and perhaps irrigation. Its ravages have always been worst on weedy plantations and new clearings. Bug. The coffee tree is attacked by various species of Coccidce in most countries, where they are known by different names. Ceylon has been, perhaps, the worst sufferer in this respect ; but careful cultivation has greatly reduced the evil. There are two distinct species of bug found in Ceylon, and called respectively " black," or "scaly," and "white,"' or "mealy." The former, Lecanium co/ece, is a minute insect, which attaches itself to the tenderest shoots of the pLmt ; the females have the appearance of small scollop shells, of a brown colour, and adhere to the leaf or twig in the same manner as the scollop shell to a rock. Each of these contains several hundred eggs undergoing incubation ; and in a short time, the whole of the green wood of the tree will become covered with the young insects, and coated with a black soot-like powder, which renders the tree easily discernible at a distance. The bug will soon spread over whole estates, entirely checking the growth of the trees ; the fresh young shoots are always first attacked, and such wood as is allowed to mature produces hardly any crop. The berries, moreover, are, in their earliest stage, destroyed by these insects, which cut them off at the stalk. The measures recommended for checking this scourge are to dust the bushes with a mixture of pounded saltpetre and quicklime, in equal parts ; or to brush or 'sponge the affected parts with a mixture of soft-soap, tar, tobacco, and spirits of turpentine, in about equal quantities. A coolie, with a bucket and a piece of rag, can perform the office effectually. This species affects elevated (above 3000 ft.), cold, damp, close localities, -where it is found in all stages of development all the year round, the propagation being continuous. It generally makes its first appearance under the shelter of a large rock, near a belt of forest, or at the bottom of a nullah. White bug is a distinct species of insect, known as Pseudococcus Adonidum. It is small, flat, oval, about -Jg- in. long, covered with a white down or fur, and having parallel ridges running across its back from side to side, like the wood-louse, though on a much smaller scale. It is found in various stages of development all the year round, and takes up its quarters on the roots of the trees to about L ft. beneath the surface, at the axils of the leaves, and among the stalks of the crop clusters, which it cuts off wholesale, either during the blossom stage, or just after the young berries have 700 COFFEE. been formed; in the latter case, its operations may easily be recognized, by the large quantities of young green berries with which the ground beneath the trees will be strewn. It is also easily discovered by a white, flour-like excretion which it deposits around the axil nooks where it has made its abode. The prescriptions above recommended for black bug will be here found equally efficacious. In either case, probably, a decoction of common tobacco might be sufficient, while much more easily prepared. The white bug has a decided preference for hot, dry situations, and generally disappears in the wet season ; too often, however, only to return as soon as the blossom has set. Canker. A disease which has created great havoc in Natal, and which causes an annual loss of about 1 per cent, of the trees in Jamaica, is "canker" or "bark disease." The first synvptom is the withering of a tertiary or secondary branch, when it will be found tliat the bark under the primary branches is decayed and blue mouldy ; the blue mould gradually extends downwards over the whole stem ; a tree once attacked never recovers, but dies in a few months. All soils and situations si-em liable to the disease, the trees beginning to suffer when about six years old. Though the mould is the proximate cause of death, the ultimate cause is evidently due to some unfavourable external condition. The opinions of experienced persons as to what this may be are various ; it is attributed to neglect of cultivation, to unsuitability of climate, and to want of depth of subsoil. All may be partially right ; but the last seems most probable, and is the reason given for it in Jamaica. Rot, Grubs, Eats, Squirrels, &c. " Rot," or the blackening and withering of the young leaves and shoots, is due to wet and cold, and may be cured by good drainage and mulching. Gruba of a large yellow kind destroy the tap-roots of the plants ; cattle manure is a fertile source of them, and should be well limed. Rats, squir. els, grasshoppers, ants and spiders collectively do consider- able mischief, and should be exterminated whenever possible. In Java, a fungus attacks the stems, giving them a white appearance, and producing death in all the parts above. In Venezuela, occurs a minute fungus named Depazea maculosa, which causes the so-called " iron-stain," circular or elliptical blotches of an ochreish-yellow colour. The same appears to be in Jamaica also. Harvesting. The clusters of buds which duly make their appearance are, at first, little, dark- green spikes ; as they grow, they become straw-coloured, then under the influence of a few showers, almost white, and finally burst into snowy blossoms. After a day or two, the flowers turn brown and fade away, the more gradually, the better. While the bloom is out, rainfall is unwelcome ; but after it has "set," a shower is beneficial. The pistils of the flowers soon assume the form of berries, gradually growing, and changing their colour from dark-green to light-yellow, which finally deepens to red. As soon as a sprinkling of red berries is seen, picking should begin ; it will con- tinue as long as any berries ripen, say 1 to 3 months. The berries, or rather cherries, must not be picked until fully ripe, as indicated by a deep purplish-crimson colour. As the crop rarely or never ripens all at once, two or three pickings are required, the second being the principal one, while the others are rather gleanings. Each mature cherry should be picked separately off its stalk, and never stripped off; the cherries as picked are dropped into a small bag say 18 in. square sus- pended from the neck ; these b;igs are emptied into 1 J or 2 bushel sacks placed at intervals on the paths. If allowed to get over ripe, in wet weather, the cherries are liable to burst and drop the beans, or to fall off bodily ; on clean ground, much may be recovered. In hot weather, the cherries are more likely to dry up and hold on to the trees. In order to convey the cherries to the curing houses, a great saving is effected, in long distances, by running them with water down galvanized iron spouting, made in 8 ft. lengths, laid with even gradients and curves, and duly secured. The cherries are despatched from cisterns, to which the due proportion of water is admitted ; provision is made for collecting and utilizing the latter at the works. PREPARATION. The preparation of the coffee necessitates the erection of extensive buildings and machinery ; for these no specific plan can be given, because much depends upon the size and situa- tion of the estate, and much upon the kind and degree of preparation contemplated. The site chosen for the works should be as near the centre of the plantation as is compatible with securing a patch of open airy ground, to which a good stream of water can be brought. The first requisite building is the " pulping house," comprising three floors the cherry loft, the pulping platform, and the cisterns. Whenever possible, it should be built against a shallow cliff or embankment, so that the cherry-coffee may be delivered into the loft without being borne upstairs. The cherry loft is usually immediately over the pulping platform. Pulping. The operation known as "pulping" consists in liberating the coffee beans from the pulp in which they are enveloped. With ripe cherries, this is most easily and effectively accom- plished immediately after picking, and efforts are usually made to complete the pulping of a day's picking during the same evening ; if over ripe and shrivelled, but still comparatively moist inside, the cherries should first be soaked in water for a few hours. A number of machines have been invented for this purpose, the object in all ca?es being to pulp rapidly, thoroughly, and without injury to the bean ; if the inner skin of the bean be broken, the latter is wasted. The most simple form of pulping machine LJ the " disc pulper," in which the separation of the bean and the pulp COFFEE. 701 is effected by means of rotating discs, covered with a thin sheet of copper, whose surface has been " knobbed," or raised into rows of oval knobs, by the application of a blind punch. Pulpers of this class, being portable and cheap, are often used in the opening of distant estates, and commonly in India and Java. The ' single " form is very light ; driven by three coolies, it will pulp 20-25 bush, cherry an hour. The " double " form, hhown in Fig 500, has two discs, and is furnished with a feeding roller inside the hopper. It requires four to six coolies to pulp 40 bush, an hour ; but driven by power, it will do 70-80 bush. The discs are placed between "cushions ' of smooth' iron, set at such a distance that the cherries cannot pass without being bruised ; the cushions rest on a movable bed of iron, set so that no bean can pass downwards. When the disc revolves, the cherries are driven forward, and squeezed ; the corrugations then catch the skins, and drag them between the disc and bed. These small pulpers have an advantage over the larger ones, in that each can be set to suit the size of a portion of the crop -which always varies ; and with a number of machines, there is less likelihood of complete stoppage in case of an accident. One disc pulper to every 30-40 acres say three to 100 acres : two to be set alike, and one for smaller cherries should be ample. The " cylinder pulper " is an older invention than the preceding, and has been subjected to numerous modifications. The principle is illustrated in Fig. 501 ; or is a cylinder of various diameter, revolving in the direction of the arrow. The cherries and water are guided between the cylinder and a piece of iron, called a " chop," 6, set at such a distance that the smallest cherry is bruised while the largest bean is not damaged. The teeth of the cylinder catch in the pulp and drug it within the second chop c, which is made sharp at the top and is set so that while admitting the pulp it rejects the beans, which fall into the trough d; the pulp passes into the trough e. The cylinder is furnished with a toothed surface, by means of a sheet of copper pierced with a number of partial perforations, so as to resemble a magnified grater. Sometimes the punching is effected in such a manner as to produce three-cornered points, the apex of the triangle being at the top; in other cases a " half-moon " punch is used, and this is said to 5 2 . reduce the percentage of pricked beans. In any case, it is essential that the teeth shall be equally raised. Care must be taken to retain a bold working edge on the lower chop, as when it becomes worn and rounded, small and dry beans are liable to be caught and broken. A very handy form of cylinder pulper is seen in Fig. 502. The pulping parts consist of an iron cylin- der a, 24 in. by 1 5 in., covered with punched copper, and a pair of iron chops set to the breast of the cylinder. Below the cylinder, is a sieve 6, provided with circular motion, for separating the clean pulped beans or parch- ment from the pulp and imperfectly pulped cherry. The parchment is carried by a spout to the cistern ; the unpulped cherry is returned to the hopper c, and again passed through. Worked by six coolies, it will pulp 30-40 bush, cherry an hour ; by power, 50-60 bush. Fig. 503 represents a " gearless " pulper. It has two pulping cylinders, two pairs of chops, hopper and feed-boxes of galvanized iron, a large sieve with circular motion, and a set of elevator buckets. It easily pulps 100 bush, cherry an hour, and can be made to do 150-160 bush. ; for effective speed, it requires a 16 ft. water-wheel, or a 3h.-p. engine. The cherry is dropped into the central hopper a, whence it passes laterally into the two side hoppers b ; from these, it drops on to 702 COFFEE. the sides of the cylinders, and the pulping is effected at the chops under .0. The pulp is floated away. The beans, together with some pulp and unpulped cherry, fall into a sieve 6 R. fifth year (cultivation, 200 A.) : weeding, 3600 ; filling up vacancies, 173 ; repairing buildings, 500; roads and trenching, 400; nursery, 100; topping, handling, and pruning, 850; manuring 50 A. at 40 R., 2000 ; gathering 7250 bushels cherry (725 cwt.), 1812 ; curing, 362; despatching to coast, 2265 ; permanent bungalow, &c., 5000 ; cattle (25 head), 750 ; keepers (6 men), 432 ; superin- tendent, 3620 ; writer, 600 ; maistries, 981 ; contingencies, 500 ; = total, 23,945 R. Sixth year : weeding, 3600 ; filling up vacancies, 175 ; buildings, 500 ; roads and trenching, 500 ; nursery, 100 ; pruning and handling, 2000 ; manuring, 2500 ; gathering 10,250 bushels, 2563; curing and de.-patching, 3715; stock, 1200; superintendent and writer, 4220; maistries, 1000 ; contingencies, 500 ; = total, 22,573 R. Seventh year : cultivation, 9375; gathering. 12,000 bushels cherry (1200 cwt.), full crop, 3000 ; curing and despatching, 4350 ; stock, 1200 ; management, 5220 ; contingencies, 5uO ; = total, 23,645 R. The balance-sheet will then stand as under : 1st year: To expenses .. .. R. 27,790 By balance R. 27,790 2nd year : To balance expenses 3rd year : To balance 4th year: To balance expenses 5th year : To balance ,, expenses 6th year : To balance expenses 7th year : To balance > expenses balance 27,790 8,199 35,989 35,989 14,811 50,800 45,175 20,566 65,742 46,617 23, 94 5 70,562 37,937 22,573 60,511 14,386 23,645 15,969 54,000 By balance 35, J By 125 cwt. crop, at 45 R. By balance By 425 cwt. crop, at 45 R. By balance By 725 cwt. crop, at 45 R. By balance By 1025 cwt. crop, at 45 R. By balance By 1200 cwt. crop, at 45 R. .. 35,989 5,625 45,175 50,800 19,125 46,617 65,742 32,625 37,937 70,562 46,125 14,386 60,511 54,000 54,000 Subsequent years : To expenses 23,645 By 1.00 cwt. crop, at 45 R. .. 54,000 Among other Indian districts where coffee cultivation has been tried, it is reported from Cidtta- gong that it yields 9, and even 12 cwt. an acre, and that thousands of acres of excellent land can be got near navigable rivers, and where manure and labour are abundant. The joint culture of coffee and tea is strongly recommended in this district, labour being available for each in its season. It has been tried, but with little success, in the neighbourhood of Darjeeling. It seems very doubtful whether occasional cold will not always be a bar to the general spread of coffee in N. India. The quantities and values of the coffee exports from British India (excluding Ceylon), for the last five years of whicli statistics have been issued, were respectively : 1874, 40,815,040 Ib. ; value, ],487,41U.; 1875, 34,925,072 Ib.; value, 1.305.335/. ; 1876, 41,662,432 Ib.; value, 1,627,027/.; 1877, 33,874,768 Ib.; value, 1,345,882J. ; 1878, 33,300,624 Ib.; value, 1,338,499*. The drought of 1877-8 affected the coffee plantations, and would of itself sufficiently account for 716 COFFEE. diminished exports, if the leaf disease and the borer did not help to keep down the yield. The average value per cwt. was a little higher than in 1876-77, having been just over 45 rupees as compared with 44 '4. The United Kingdom and France are the two largest consumers of Indian coffee, although in both countries it ia subject to excessively heavy duties. The Austra- lian cokmies consume large quantities of tea and coffee ; but they take neither the one nor the other from India. Producers in India have hitherto found a ready market in Europe for their whole pro- duction, and have had no inducement to essay the opening of a trade with Australia. Nevertheless the trade would certainly become a source of considerable profit to India, and it would be well worth while to direct attention to the matter. The exhibitions at Sydney and Melbourne oner excellent opportunities for introducing these staples to the notice of the colonists. Java. Java is the second largest coffee-producing country, nine-tenths of the culture being in the hands of the Government, and effected by forced labour. Around the estates a fence is planted, about 12 ft. from the outer row of the plants, generally of thejarak, or castor-oil plant (Palma Christt), intermixed with the dddap, or the silk-cotton tree ; and, in low situations, outside of this a ditch is dug, to carry off the water. These operations commence in August or September, and by the time the ground is in perfect readiness for planting, the heavy rains are nearly over. The plants are either raised from seed in nurseries, or the estates are supplied with " stumps " from wild or casual seedlings- Nursery plants are generally removed at six months, when they are about 12 in. high ; their after growth is so rapid, that in nine months they attain to 2-3 ft. in height, and at twenty months are 6-8 ft. high, and capable of bearing f Ib. prepared coffee per tree. The trouble and expense of nurseries in so hot a climate are, however, very great, and the second plan is often adopted. In this case, the plants grow more slowly ; but they become more lasting and hardy trees. The planta- tions are generally laid out in squares. The distance between the plants varies according to the fertility of the soil ; in a soil not considered fertile, a distance of 6 ft. is preserved ; but in a rich soil, where the plant grows more luxuriantly, 8 ft. x 4 ft. is the scale hitherto commonly used. Now, these distances are deemed too small, and new estates are being laid out at 10 ft. x 9 ft., and 9 ft. x 9 ft. At all altitudes below 2500 ft., shade seems necessary, especially during the early growth of the coffee-bushes. The tree almost universally employed for this purpose is the dddap (Erythrind), of which several varieties are abundant throughout the island, the scrap, the ddri, and the wdru ; the first is preferred as affording the greatest shade. It is propagated by cuttings ; and in selecting them fur the coffee plantations, care is had that they are taken from trees at least two or three years old, and that they are 3-4 ft. long, of which 1 ft. at least must be buried in the ground. After the dddkips are planted, holes are dug, l-2 ft. deep, for the reception of the coffee plants. It is a common saying that where the dddap flourishes, there also will coffee grow ; but they are not always constant or necessary companions, for many gardens in high lands contain few dddaps. It is probable that in future these trees will be largely replaced by Acacia Julibrissin (Albizzia Moluccana), which grows very fast, and is superior for several reasons. Indigo is frequently planted among the young coffee, chiefly in order to keep down the weeds, but also to be used as manure. As the tree waxes, no attempt is made to train it, and it grows up with several stems as a native tree. It is pruned only when branches show signs of decay, or when the borer, which ia very destructive, compels the planter to cut down the attacked stems. The weeds are dug up with maramoties, to a depth of 6 in., and piled in rows between the shade trees parallel to the lines of coffee. These weeds, among which is the alang-alang, and other fodder grasses, furnish valuable cattle food. When an estate shows signs of decay, the coffee trees are all cut down, the dddap trees being either felled or ringed near the roots, so that they may decay gradually and fall piecemeal to the ground ; the process of replanting is then repeated in the same manner as before. Thus the land may be replanted several times, and so rich is it that the last garden will be better than the first. On the other hand, the climate is as a rule far too forcing for permanent culture. The average crop is very light ; and after 12-14 years, the yield is so small as not to repay the cost of harvesting. On estates below 1000 ft., the trees bear earlier and produce more, but do not last beyond ten years , at altitudes of 3000-4000 ft., they may last 30-40 years. On many of the elevated plantations, the trees grow to a height of 30-40 ft., necessitating the use of ladders to gather the crop. Such trees are grown 25 ft, x by 25 ft. apart, on terraces 25 ft. wide, planted with grass at the edge, or all over, to prevent wash. These trees yield 6-7 Ib. prepared coffee. The average produce of the Government plantations is reckoned, by Jagor, at only Ib. a tree ; that of the few private estates at 1 Ib. a tree , the difference is attributed to the ill effect of forced labour. The methods of cultivation adopted by the private planters vary considerably , in some instances, the trees are topped at 4-5 ft., and pruning is attempted, but the results are not satisfactory. The condition of the Government culture has remained stationary during the last forty years. The season affords what are termed three crops; the first is but small, the second is most abundant, and the third is rather a gleaning. Owing to the scarcity of water, the labourers convey the cherry coffee to their own homes, where they pulp and wash it with wooden pestles. Attached to every principal village, near which there are coffee plantations of any extent, there COFFEE. 717 is a drying-house, to which the pulped coffee is brought ; it is there placed on hurdles, about 4 ft. from the floor, under which a slow wood fire is kept up during the night. The roof of the drying- house is opened at morning and evening to admit the air, and the berries are frequently stirred to prevent fermentation. As the direct heat of the sun is considered prejudicial, the roof of the house is cl >sed during the day. This operation is repeated till the parchment is quite dry. The berries dried in this way are small, of a sea-green or greyish colour, and are supposed to acquire a peculiar flavour from the smoke, although it does not appear that any particular kind of wood is used for fuel. When dried in the sun, the bean becomes of a pale bleached colour, is larger, specifically lighter, and more insipid to the taste than the former. According to Jagor, a period of five to six weeks is required. The most common mode of freeing the bean from the parchment is to pound the berries, when dry, in a bag of buffalo -hide, great care being taken not to bruise the beans. A mill of simple construction is sometimes used, but is not found to answer so well. The coffee beans are then put into bags or baskets, kept on raised platforms till the season of delivery, when they are carried down to the store-house, sometimes by men, but generally on the backs of buffaloes and mares, in strings of 1500-2000 at a time. In some instances, however, improved machinery has been erected for pulping and curing the coffee on the West Indian plan. The crop of 1878 was estimated to be 20 per cent, below the average, chiefly owing to the drought of 1877- The finer descriptions of Samarang (West Indian preparation), Buitenzorg (ordinary preparation), Government Preanger, and Government Padang, commanded high figures ; nearly the whole of the two latter brands was bought up for the United States at very advanced figures. Further large impor- tations of Liberian coffee seeds and plants took place during the year ; but from the short period of its trial, no reliable opinion can yet be formed as to its suitability. These importations were effected from or through English houses, Ceylon growths being prohibited on account of the leaf disease. The exports of Java coffee, from 1st July, 1877, to 30th June, 1878, stated in pkuls of 122 lb., were, to Holland, 1,096,372 ; France, 14,767 ; Port Said, for orders, 6943 ; Italy, 5775 ; Singapore, 5079 ; America, 3993; Australia. 1107; Channel, for orders, 102. Liberia. The Guinea Coast of Africa, and more especially the republic of Liber'a, is remarkable among coffee producing countries, as the home of a peculiar species of coffee, formerly known as C. microcarpa, but now finally designated C. Liberica. It is distinguished from C. Arabica by mucli more robust habit ; it attains a greater height, and both leaves and fruit are larger and less delicate ; it also prefers low elevations. In its native country, this species grows as well near the sea (100 yds., or less distant), as thirty miles inland, and the wild plant is found even yet further towards the interior. The general temperature of the coast districts ranges between 22 and 31 (72 and 88 F.) in the shade, the maximum being 33 (91 F.) and the minimum 17 (62 F.) ; away from the sea, the temperatures decline l-2 F., principally owing to the rise of the land. The limits of elevation are from sea-level on the coast to 550 ft. inland. It is as much at home on flat land as on hill slopes, provided always that the land is drained. Though the cultivation of this plant in its native soil was started by the late President Roberts, and is extending every year, attention has principally been paid to its acclimatiza- tion in other countries. In Ceylon and Southern India, some hundreds of acres are already planted with it, and the movement is still extending. A point greatly in favour of the plant is the low altitude at which it flourishes, thus permitting the utilization of land otherwise unproductive. At the elevations where C. Arabica is best cultivated, this species refuses to grow, and perhaps the highest successful plantation is at about 1500 ft., at which height it was found beneficial to leave some of the forest trees as shade; probably the planting of coco-nut trees would be better. The young plants require careful protection from wind and extreme heat ; but soon become hardy. The size of the trees is such that an acre will not conveniently contain more than 450. At a greater elevation than 800 ft., difficulty is experienced in ripening the fruit. Planters are sanguine that a hybrid between the Arabian and Liberian species would flourish in the zone of 1000-3000 ft. The hope that the new species would be proof against leaf- disease has been somewhat disappointed ; nevertheless, the trees are very much less affected than the common shrub. The trees appear also to demand less rain and to withstand greater heat. On the score of longevity, there appears to be little difference between the two kinds. They mature early, and bare heavily ; one estate in Ceylon had trees yielding a ton an acre at 4 years old ; and 7 cwt. an acre is said to be an average crop. The idea of its entirely replacing the longer known variety is fanciful, yet by cultivation and preparation much may be done to improve the inferior flavour and coarseness of the berry, which now prevent its being used alone. The plant has been largely introduced into other of our Colonies, into Brazil, and by the Dutch into Java. In the West Indies it grows exceedingly well, and bids defiance to the blight (Cemio- stoma coffeelluni); it has a further advantage in this case that the ripened berries remain so long on the trees as to enable the crop to be gathered by few hands. It flourishes best on the " heavy bottom " lands, and in poor moist lands, and is recommended as particularly valuable for planting on cocoa estates. By grafting or inarching the Arabian species on stems of Liberica, an inert ascd growth is obtained. ' 718 COFFEE. Madagascar. Coffee grows well in most parts of Madagascar ; in recent years, large plantations have been formed along the banks of the rivers on the eastern side of the island. These are chiefly managed by Creole traders, who employ slave labour. Coffee already promises to become a very important article of export. Mexico. Though Mexico scarcely figures in the coffee-producing countries, its capacity and adaptability have been tested by successful cultivation. The productive regions are found on the sea slope of the mountains : on the Pacific side, from Guatemala, for more than a thousand miles to the north, till reaching a line of occasional frost in the State of Sinaloa ; and on the Gulf coast, from Yucatan into Tamaulipas, for more than a thousand miles. In addition, it flourishes in the valleys of the interior, wherever the table-land is depressed to the level of tropical and semi-tropical vegetation. The elevation above the sea, at which it is cultivated, varies from 4500 ft., and even higher, down to nearly sea-level in many localities on both coasts. The production need only be limited by the extent of land brought under cultivation. Mexico as a coffee-producing country has been tested by more than fifty years of experience. That coffee has not assumed the first place in exportation is to be attributed to the same causes which have retarded all development of the country. Hitherto, the production has been mostly consumed by the home demand, which is quite large, as coffee is in very general use by all classes ; but during the past few years, the cultivation has increased, so that a small exportation has commenced. The statistics of the port of Vera Cruz indicate a steady development of the export, which ought in a few years to become considerable : 1871, 672,588 Ib. ; 1872, 1,912,020 ; 1873, 3,909,446; 1874,4,204,446; 1875,5,375,678. The young plants are transplanted from the nurseries at twelve to eighteen months, to the fields, which are prepared in open forests, and on mountain sides affording shade. In open fields, a growing shade must be created, usually by planting bananas ; but the best cultivators set out cinchona and valuable timber trees, as oak, walnut, &c. The second year after planting gives a very slight yield of coffee ; the third year, about a half crop ; and the fourth year (or when the plant is five years old), a full crop. The plants are set out usually about three yards apart each way, though often closer. The cultivation consists in keeping the fields clean, and ploughing ; in certain localities, irrigation is necessary ; the best planters prune carefully, keeping the height at 6-8 ft. The first flowering is sometimes as early as December ; the second, in February ; the third and most abundant, in March and April. The berries are dried by exposure to the sun, when they shrivel, and change to a black colour. They are then put into a mortar, and the beana are hulled or beaten out with a pestle, and are then separated from the parchment by the crude process of winnowing, though sometimes a fan-mill is used. So far, no disease of plant or berry has appeared ; and although great drought may diminish the crop, it does not destroy it. The flower, when in full bloom, is sometimes broken off by severe winds ; but this seldom diminishes the yield. The trees continue bearing for twenty to twenty-five years. There are, however, trees sixty to seventy years old, which are yielding a fine crop. The average yield per tree is about 1 Ib., though with intelligent pruning and manuring, it may be increased to 3 Ib. a tree. It is not uncommon to find trees yielding 5-7 Ib., and in very exceptional cases, 25-50 Ib. each. After the plants begin to bear a full crop, the annual cost of cultivation, up to sale in local market, is 6-7 cents. a pound. The above remarks refer especially to the region around Cordova, which is at present the greatest producer of the republic, and the most accessible to the American market ; but several other localities are assuming some importance. One of these is the district of Soconusco, in the State of Chiapas, immediately upon the borders of the republic of Guatemala. Several foreigners and a number of resident proprietors have embarked in the cultivation. The special advantages presented here are cheapness of land and labour ; the chief impediment is the fact that this district is disputed territory, claimed by both Mexico and Guatemala, and the tenure and protection of property are insecure.- The valley of Uruapan, in the State of Michoacau, has great celebrity for its superior quality of coffee. But the most noted region is the State of Colima, on the Pacific coast ; its product is so highly esteemed that it commands a fabulous price in the City of Mexico, and more distant places in the republic. The favourable report on sample lots sent to Europe in 1873 gave an impetus to the cultivation. Since that year, over one million plants have been set out, and are now beginning to bear : planting continues to increase, and coffee promises to become the principal article of export. The demand is so great that large lots fetch 27^ cents per pound at the plantation, mainly for consumption in the interior, a small portion only being shipped to Germany by resident German merchants, on private orders. Colima, and some other States, have passed liberal laws for the encouragement of coffee cultivation, offering premiums for the largest crop produced, and exempting coffee lands from all taxes. Natal. Coffee culture in this colony seems to be struggling against adverse conditions, notably the disastrous spread of the bark disease, for which no cure has been found. This is the more to be regretted as the quality of the beans is very fair, and the demand for the article is always growing. The causes of the disease do not seem to have yet been sufficiently investigated, and without this COFFEE. 719 there is little good in making suggestions as to shade, manuring, pruning, &c., as remedies. The evidence in favour of partial shade in many localities is strong ; for this purpose, local varieties of rythi-ina might he used, as in Java, &c. One planter expresses himself very strongly on the subject of topping : he condemns the adoption of a universal standard of height, and recommends for the coast lands, a height of 6-8 ft. ; and for the higher lands, ranging from Fields' Hill upwards, about 5 ft. Unlike Ceylon, elevation seems but little to affect the value of Natal estates ; but river-beds, and low, dump places, being liable to frost, must be avoided. Too little attention, perhaps, has been given to irrigation in the dry season. The best months for making seed-beds are September or February : when the former is chosen, tlie seedlings should be ready for the nursery at the time of the autumn rains (March) ; when the latter, the spring rains (September-October). A safeguard against the young plants being scorched is found in large castor-oil leaves ; they are cut with about 9 in. of stalk, and are stuck into the ground, between each plant and the sun, soon drooping, and forming sun-shades. The plants are said to begin bearing in eighteen months after transplanting, the yield gradually increasing till the 7th or 8th year, when they should give full crops. A fair average crop is put down at lib. a tree all round. Nearly all the crop is used in the colony or neighbouring republics, consequently the Customs returns only show a very small proportion of the annual yield ; it is impossible, however, that the entire yield of the colony has ever exceeded 20,000 cwt. The exports were, in 1874, 680 cwt. ; 1875, 363 ; 1876, 179 ; 1877, 91. Nicaragua. A few coffee estates exist; but the export is very trifling some 400-500 Ib. annually. Pacific Islands. Coffee has been successfully introduced into the Fiji and the Friendly Islands, and in the course of a few years it will probably form an important export. Trees raised from seed bear fruit in the fourth year. In the Sandwich Islands, the cultivation is also progressing, large plantations having been laid out with a view to supplying the markets of Sydney, California, and Chili. Almost the whole of the produce goes at present to the United States, the small remainder being taken by China and Germany. The total export, in 1878, was 127,963 Ib. Peru. Coffee grows luxuriantly on the mountain slopes, the crops often being so heavy as to necessitate artificial supports for the branches. Nevertheless, the export from Mollendo, the second port of the republic, amounted only to about 140 cwt., in 1878. Philippines, $c. Coffee thrives remarkably in the Philippines, and the berry possesses a peculiar flavour which is highly esteemed on the Continent, so that though it is by no means well prepared or nice looking, the worst brands fetch a higher price than Java growth, and the value on the spot far exceeds the current rate of the London markets. There are two kinds of coffee, viz. " Manilla " and " Zamboanga." The former is grown in the islands of Batangas, Indan, Laguna, and Cavite ; its price in place, in 1878, varied between 19J dol. and 22 dol. (dol. = 4s. 2d.) a picul (139 Ib.) ; the beans are medium-sized, and pale-green in colour. The latter variety comes from Mindanao, and the southern islands generally. The beans are larger than the " Manilla," but yellowish-white in colour, and flabby in texture ; samples also always contain much rubbish ; local prices, in 1878, fluctuated from 17J to 21 dol. a picul. The exports of all kinds from Manilla weie, in 1877, 3843 tons, value 245,980/. ; and in 1878, 2306 tons, value 147,560;. The proportion sent to Great Britain, in the latter year, was only 160 tons, and to British Colonies, 242 tons ; the remainder was taken by Continental Europe. Shipment is effected in bags of 150 Ib., or in cases of 200-300 Ib. In the islands of Cebu and Bohol, the natives have planted patches of coffee, and small parcels of " parchment '' were offered in 1878. The quality is excellent, and the price stood at 14-16 dol. a picul. Small quantities, of inferior growth, from Yligan in Mindanao were offered at 12-13 dol. a picul. In Timor, the Portuguese are extending the cultivation among the natives; the trees mature early, 1J cwt. of coffee being obtained from tii'ty trees in 4-5 years. In Amboyna, also, a number of trees have be n planted. Siam. In the hilly districts of the East Coast of the Gulf of Siam, tins cultivation is carried on to a limited extent. Some fine samples were shown at the Exhibition of 1862. Straits Settlements. After a fair trial, it seems that coffee planting in Penang has not been a success. During the first 12-18 months, the plants grow well, and are strong ; but the effort of bearing fruit, under the influence of long-continued drought, weakens them so that they lose foliage and fall a prey to disease. Under shade, on the plains, they stand better ; but the crop ia very light, and often fails altogether. On the Great Hill, the plants bear better; but the planta- tions are restricted to narrow limits. Liberian plants have been introduced into Singapore and Sarawak, and promise well. Sumatra. Among the Eastern Archipelapro, this island ranks next after Java in the quantity of its produce, the cultivation having been largely adopted by the natives. The quality of the berry varies much ; the dark-yellow or brown are the best, the black are inferior. The annual crop may perhaps reach 20 million Ib. Surinam. A. century ago, this colony produced 7 million kilo, of coffee; this enormous quantify has gradually dwindled down to insignificance : In 1875, the production was 37,357 720 COFFEE. kilo.; the export, 644 kilo.; in 1876, the figures were 12,412, and 325; in 1867, 6179, and 159. In this last year, there was one estate planted with coffee aud cocoa, and four with coffee and plantains. United States. The Department of Agriculture, at Washington, has recently issued a circular relative to the possibility of coffee culture in some of the States, and is led to believe that the con- ditions of climate and soil will be found suitable in Florida, Lower California, and part of Texas. It is stated, indeed, that in the two former is found an abundance of wild coffee. In California, seed obtained from Costa Eica has been planted, and the results hitherto are satisfactory. Venezuela. The annual production is about million cwt., the best being grown in the cooler portion of the State. The crop is gathered in October ; the cherries are spread on hurdles exposed to the sun, where they ferment for 14-20 days, and then dry. Pulping is performed by machinery, and the parchment is winnowed away. The average crop is generally placed at Ib. a tree, which in some localities is reduced to J Ib. West Indies. The decline of coffee culture in the British West Indies since the emancipation of the negroes almost amounts to abandonment. It is commonly attributed in great measure to the ravages of the blight already described ; but it is evidently traceable rather to social influences and a faulty system of agriculture. Serious attempts are now being made to restore the industry to some of its former importance, so that a sketch of the principal conditions of successful culture may be opportunely given. The best soil is an open, dark-brown or reddish loam, 1-2 ft. thick, resting on finely disintegrated but undecomposed vulcanic rock. Some of the finest ground exists on declivities which can be traversed only by planting the feet at the base of the coffee stems. On some hills of this character are now to be found trees 60-70 years old, which have been uprooted and have re-established themselves. In the face of this fact, the renovation of the existing abandoned plantations should be an easy matter. The trees should be relieved of the mass of bush, weeds, and "provisions" which now smothers them, and should undergo a judicious pruning, extended over three years if necessary. In this climate, shade and shelter are undoubtedly beneficial. On old, overgrown plantations, natural shade may be left when clearing, taking care to select trees of small foliage for the purpose. When laying out new estates, greater choice will be possible. In many instances, cocoa has been planted amongst the coffee, probably with a view of getting crops of both from the same ground. It is quite possible to grow them profitably on the same field ; but each must have its own sufficient space, and thus there is no gain ; besides, their habits of growth are unsuited to the arrangement. For the purpose of shelter, there is, perhaps, nothing better than the pois-doux tree, especially on inferior soils and in exposed situations ; hedges of it planted as a break-weather are to be found on every abandoned estate. The pimento is equally suitable, but is of slower growth. Neither is of any value as a shade-giving tree. Of all indigenous plants, the Moricypre (Byrsonina spicata) appears to be the most suitable as a protection against both suu and wind ; it is a small-leaved, fast-growing, medium-sized tree, and common everywhere. The distance from tree to tree will depend on the variety of coffee grown, and the character of soil and of situation ; but it is indicated by the principle of each plant being so far from its neighbour, that when all have grown to their fullest size, they do not touch by about 1 ft. Thus the distance may vary from 4 to 8 ft., or eveii more. A very important factor in the sum of influences whicli have brought the culture to its present low ebb is to be found in the greatly diminished moisture of the climate occasioned by the wholesale destruction of the forests. This is especially the case with plantations on steep hill- sides ; and it remains to be seen what art can do to combat the difficulty. Cuba. In 1847, there were over 2000 coffee estates, yielding nearly 50 million Ib. annually ; in 1851, sugar and tobacco had so far replaced coffee that the production fell to 13 million Ib. ; and now Cuba imports coffee from Porto Rico. Dominica. From an annual production of over 2 million Ib., Dominica has fallen to nil. The effects of the negro emancipation and the coffee blight were, perhaps, felt more severely here than in the other islands. The export tariff is 13d. a cwt. Grenada. At one time, Grenada coffee was one of the only three brands known in the London markets ; cocoa has now taken its place. Guadaloupe. A century ago, this French colony exported 7J million Ib. of coffee, in 1874, the exports were 625,200 Ib. It nearly all goes to France as of Martinique growth. In 1873, there were 3588 hectares under coffee, yielding about 1000 Ib. a hectare (= nearly 2 acres). Hayti. Hayti has fallen from a production of 80 million Ib. in 1789, to 54 million in 1874, chiefly owing to disastrous hurricanes. The exports in 1878 were, to Italy, 83,000 Ib. , Spain, 17,000; West Indies, 11,000; France, 3000; United States, 2000; Great Britain, 1400. Jamaica. This hilly island used to produce large crops of fine quality. The average annual shipment in 1805-7 was 28 J million Ib.; this fell to 4 million in 1864 , but increased to over 10 million in 1874. The export, in 1875, was 7,136,327 Ib ; 1876, 8,707,552; 1877, 9,532,887. An export COFFEE. 721 duty of 6s. a tierce is levied. Renewed efforts are being made to extend the cultivation, and what appear to be rather extravagant hopes are being based upon the introduction of Liberian coffee. Some plants of this variety, introduced in 1874, were placed in cinchona propagating houses, and then distributed to planters at all altitudes ; those put out at the lower elevations attained the greatest success. lu Jamaica, common coffee is cultivated at all heights, from the sea-level up to 5000 ft. The superior qualities, however, are only produced at heights ranging above 2000 ft., beneath which altitude the quality decreases in value as it approaches the level of the sea. As the peasantry, who are now the largest producers, almost exclusively cultivate their coffee below 2000 ft., the acquisition of a species adapted to the climate of the lowlands is a matter of great importance. A gradual diminution in the area of plantation coffee is taking place. The soil of the Port Koyal Mountains, in which the best coffee is grown, is becoming more impoverished from year to year, and all the land adjacent to these plantations has been in a great measure exhausted by coffee cultivation, so that there is very little available land in their immediate proximity. These fields are confined to the southern slopes of the Blue Mountain range. The northern slopes, except near the sea, are covered with dense primeval forest, no attempts at cultivation having been made here, though these lands are the most valuable in Jamaica for coffee cultivation. It is im- portant, however, to bear in mind that the conditions of humidity differ on the northern and on the southern slopes. On the latter side, the destruction of the forest has materially lessened the moisture, thus rendering the climate comparatively dry. The area of unoccupied land favourable for coffee, including forest on the eastern prolongation of the southern slopes, may be roughly estimated at 60,000-80,000 acres, nearly all of which belongs to government. The total area in the island now under coffee cultivation, much at unsuitable elevations, is 22 000 acres. Martinique. Here also coffee culture is declining, in spite of new lands being taken up. The acreage probably amounts to about 1400, the yield being reckoned at 500-1000 Ib. a hectare (2 acres) ; the total production in 1873 was 210,000 kilo. ; it is mostly consumed iu the island, France taking the little that is exported. Porto Rico. Coffee cultivation might be extended here on now unproductive land. Considerable quantities are grown in the province of Ponce, and minor quantities in Mayaguez, Arecibo, and Aguadilla. The quality is excellent, and though not well known in England, it is valued in Latin Europe. Shade is provided according to the needs of each plant. The beans are garbled for market, and those intended for the Mediterranean are polished in a mill, with the addition of a little colouring matter when necessary. The exports in quintals (of 101J Ib.) were, in 1874, 199,488 ; 1875, 256,485; 1876, 306,526; 1877, 137,140, 1878, 151,204. The destinations of the export of 1878, were: Spain, 16,771; Italy, 15,406; France, 5908; Great Britain and provinces, 5472; Germany, 4279 ; United States, 34 ; other countries (principally Cuba), 103,334. Trinidad. The coffee export reaches about 25,000 Ib. yearly. There is said to be scarcely any part of the island where coffee culture may not be profitably undertaken; but the dis- tricts of Maracas, Aripo, and North Oroponche are regarded as possessing conditions not to be surpassed. The export duty is \\\d. a cwt. The island possesses a fine Botanic Garden, in which are grown some ten varieties, or sub-varieties, of coffee. Some notes concerning their peculiarities may be of interest : (1) Liberian coffee seems to be regarded as a means of re- viving coffee culture in the Western Tropics. The plants thrive well in the ordinary red gravelly loam of the northern part of the island. From the nature of its growth, it must be planted widely, and topping is recommended at 7 ft. Prestoe advises an interval of 16 ft. between the trees, the space to be temporarily occupied by common creole coffee, which would benefit by the shade, and afford a quicker return ; the latter are to be removed as soon as the Liberian plants require room 5 say at the 6th-7th year. (2) A narrow-leaved coffee received from Java seems well adapted for poor, rocky soils. It resists drought, is very prolific, and has a large bean ; but it is slow of develop- ment. Its peculiar foliage enables it to withstand heat and drought, and renders it unliable to attack from insects and fungi. It should be planted at 6 ft. ; its sturdy but stunted growth is said to obviate the necessity for topping and pruning. (3) Souffriere coffee has been so named from its occurrence on the Souffriere Hills of Dominica, where the \ lants remained uniformly fruitful and healthy, while surrounded by creole and Mocha trees all affected by blight and drought. The texture of the foliage makes it proof against insects ; the natural habit of growth is trichotomous ; and the bean is large. It seems suited for steep and barren hill-sides, and though less hardy than (2), it develops more quickly. (4) The Mocha variety is sub-divided into major and minor ; the former attains a height of 7 ft. ; the latter, rormerly cultivated in the Muraval, St. Ann's, and Laventille valleys, does not exceed 4-5 ft., yields a smaller bean, and is less prolific. The northern hills and valleys of Trinidad might grow both sub-varieties, major in the low ground, and minor on the hills. Prestoe says that as a rule they would become most prolific under full exposure (pre- / eumably to the sun), after being established by the shade afforded by such crops as pigeon-peas, &c.' Even sucli a scorching as to cause a partial shedding of the leaves he considers beneficial. (5) Bengal coffee differs from the others, in a very compact growth, small and long bean, and a 3 A 722, COEK. preference for dense shade. Its peculiarly-shaped bean places it among second-class coffees 39 regards market price ; but it is recommended for planting with cocoa, when this system of double cropping is practised. Bibliography. J. B. A. Chevalier, ' Du Cafe' (Paris: 1862); W. G. Mclvor, Laborie's 'Coffee- planter of St. Domingo ' (Madras : 1863) ; A. B. W. Lascelles, ' Nature and Cultivation of Coffee' (London: 1865); C. E. A. Le Comte, 'Culture et Production du Cafe' dans les Colonies' (Paris: 1865); W. H. Middleton, 'Manual of Coffee-planting' (Natal: 1866); W. Sabonadiere, Coffee- planter of Ceylon ' (London : 1870); K.H. Elliott, ' Planter in Mysore' (London : 1871); Moreira, ' Breves Consideracoes sobre a Historia e Cultura do Cafeiro ' (Rio de Janeiro : 1873) ; P. H. F. B. d'Orli, ' Culture du Cafe,' &c. (Paris : 1874) ; H. E. Stainbank, ' Coffee in Natal ' (London : 1874) : H. Prestoe, 'Report on Coffee in Dominica (Trinidad : 1875); A. Riant, 'Le Cafe,' &c. (Paris; 1875) ; W. P. Hiern, ' African Species of Coffea ' (Jour. Lin. Soc. : 1876) ; R. Hanson, Culture and Commerce of Coffee' (London: 1877); E. C. P. Hull, 'Coffee-planting in S. India and Ceylon (London : 1877); P. L. Simmonds, ' Tropical Agriculture ' (London : 1877) ; L. Rice, ' Mysore and Coorg ' (Bangalore : 1877-8) ; G. Pennetier, ' Le Cafe ' (Paris : 1878) ; R. B. Tytler, ' Prospects of Coffee Production ' (Aberdeen : 1878) ; T. Christy, ' New Commercial Plants ' (London : 1878 ) ; G, Anderson, 'Coffee Culture in Mysore ' (Bangalore : 1879) ; J. Hughes, ' Ceylon Coffee Soils and Manures ' (London : 1879) ; D. Morris, ' Handbook of the Coffee-leaf Disease ' (London : in press) ; A. M. and J. Ferguson, ' Planting Directory ' (Colombo : at intervals) ; Hon. M. Romero, ' Cultivo del Cafe en la Costa Meridional de Chiapas,' (See Beverages Coffee). CONDIMENTS.-See SPICES. CORK. (FR., Liege ; GEB., Kork.y The bark of trees consists, inwardly, of a paienchymatous or soft cellular tissue, and, outwardly, of a harder woody tubular tissue, the latter being generally the more abundant. If the growth of the parenchyma be prolonged and rapid, it will assume a more or less cork-like character, as in the case of some of the elms, the common oak, and many other trees. This peculiarity is developed to an exceptional degree in one species of oak, which has been named, from this circumstance, Quercus suber ; it is the bark of this tree which constitutes the cork of commerce. The tree is an evergreen, growing to a height of about 30 ft. ; its acorns are edible, and resemble chestnuts in taste. It does not require a rich soil, but seems, on the contrary, to thrive best on poor and uncultivated ground. It is indigeBOUs to the basin of the Mediterranean, and was introduced some years ago into the most temperate of the United States of America, for acclimatization. The principal cork-producing countries are : Portugal, especially the province of Alentejo. This cork is inferior to the French, but superior to the Italian, and is mostly shipped from Lisbon. Spam, particularly Catalonia and Valencia. Italy (Tuscany). A lighter and whiter variety than the Sardinian, and considered the second best imported to this country. Sardinia produces a kind easily distinguished by its colour and weight, being pinkish-hued and heavier than the Tuscan or African sorts ; said to be the best imported by us. In 1861, it was reported that the cork forests of Sardinia and Corsica had been in a great measure destroyed by improper working. France, most abundantly in Languedoc, Provence, the environs of Bordeaux, and the Depart- ment of Var. Africa, whose product is reckoned inferior to Tuscan. In Morocco, there are several cork forests, notably at El Araish. Algeria seems to be peculiarly favourable to the development of the cork oak, the climate having a uniformly high temperature, with profuse nightly dews, while the dry, warm, open hill sides are covered with a sufficiency of light soil. The cork thus becomes finer, more elastic, less porous, and more free from earthy particles than in Europe. The tree attains a larger growth here. The bark is usually dried in the sun ; but if wetted during that operation, the drying is completed by artificial heat. There are over 2J million acres of cork oak forest in this province, of which about 300,000 acres are utilized. It is said to be capable of producing as much cork as all the rest of the globe, if only the people could be kept to peaceful agricultural pursuits. The tree attains to as great size in Britain as in Spain, and might be an object of cultivation in some of the warmest parts of these islands ; but there is every probability that the wetness of the climate would seriously impede the operations of the cork harvest. Portuguese acorns were planted, in 1859, in Wayne County, Mississippi, and all grew; the argest tree, eleven years later, measured 13 ft. in height. The trunk had attained a diameter of 11 in., and the cork bark was more than 1 in. thick. In 1872, the planting of cork trees wa extended to Southern California. CORK. 723 From a correspondence which has taken place between the director of Kew Gardens and the Crown agents for the Colonies, on the subject of a supply of cork oak acorns to the Cape, it appears that the experience of sending them out to the Punjab proved that they lost their vitality very rapidly, and it became necessary to rely eventually upon a supply of young plants raised at Kew, and sent out in Wardian cases. Numerous cork oaks, however, already exist in the neighbourhood of Cape Town, and bear acorns freely, and it is believed that if these were systematically collected and sown, an adequate supply of young seedlings would very soon be procured. In the humid district of Western Port, Australia, imported cork oaks grew 4 ft. in one year. Two other species of Quercus are found in Australia, viz. Q. pseudo-suber, and Q. occidentalis : the bark of the former is inferior for cork ; but the latter, which ia hardier than Q. suber, is said, by Professor von Mueller, to produce a very good cork bark. Among the conditions necessary to successful cork culture, climate and soil are foremost in im- portance. In the Mediterranean basin, the tree favours altitudes varying from 1600 to 3200 ft. ; as regards latitude, it does not flourish beyond 45 N. ; while the minimum average annual tempe- rature must not be less than 13 (55 F.). The most generally suitable aspect is southerly. Slopes are always preferable to flat lands, as affording a more free circulation of air and admission of light. Considerable care should be shown in the selection of the soil. It is said that the tree in a wild state is found only on the older geological formations, as granite or clay-slate ; and the experience of cultivators is that the best cork, and the most rapid growth, are produced on granitic, siliceous, and slaty (Silurian) soils, while the tree almost refuses to grow on calcareous soils. It requires abundant moisture combined with efficient drainage. Planting is usually performed with seed. As a rule, large sweet acorns develop into trees of regular growth and yielding the finest cork; while small and bitter acorns produce trees of a coarse and inferior nature. The most approved method of planting appears to be the " furrow " or " belt '* system, which consists in sowing the acorns at 20-40 in. apart in a furrow between two or more rows of grape-vines, placed at 5-7 ft. apart. The sowing and planting are conducted simultaneously, the vines affording the shelter which is so necessary to the cork tree during its early growth. The young cork trees are thinned out as required, so as to afford abundance of air and light to each. French siviculturists recommend an average of 110-120 trees a hectare (about 2 acres), and calculate the production of cork at about 8 kilo, (say 18 Ib.) a tree. The trees should be barked according as they arrive at maturity for the operation, rather than at fixed intervals independently of their condition. It is highly important to keep the forests cleared of the naturally-shed virgin cork, on account of the chances it offers of creating a conflagration. The distinguishing feature of the cork oak is that parenchyma forms the mass of the bark. In the earliest stages of its growth, it is much less elastic than it ultimately becomes, owing to its con- taining, in the first instance, a large proportion of woody matter. The outer casing of the bark is formed during the first year's growth, and does not subsequently increase ; but the parenchyma con- tinues to grow, as long as the tree is alive. In consequence of this phenomenon, the pressure of the growing parenchyma beneath forces the outer shell to split and peel off in flakes. The substance thus shed under natural conditions is known as " virgin cork " ; it is very coarse and of woody texture, its applications being, for these reasons, very limited. But the forcible removal of the cork bark, when performed in a judicious manner, is fortunately unattended with any evil consequence to the tree ; on the contrary, the operation seems to hasten and assist the growth of the bark, improving its quality, at the same time that the tree waxes more vigorous, and attains greater longevity, trees which are regularly barked living to 150 years and upwards. The age at which the first stripping may be attempted varies, with the locality, from fifteen to thirty years, the former being the most general. The yield much resembles the naturally-shed virgin cork, and is commonly included under the same term. Subsequently the barking is repeated at regular intervals of eight or ten years, the quality improving on each occasion. The second crop is, also, still too coarse for any but inferior uses. The cork harvest, as it may be called, takes place in the months of July and August, when the second sap flows plentifully. It is conducted in the following manner. An incision through the cork bark is first carried round the tree near the ground ; then a similar cut, parallel 608> to the first, is made just under the first branches ; these are united by others of equal depth drawn longitudinally, and dividing ( \^ the bark into broad planks. The instrument employed in the barking operations is a sort of axe, Fig. 508, the handle of which is flattened into a wedge-like shape at the extremity ; in short, it ia not unlike the axe used in this country for barking the common oak. After cutting, each plank is loosened from the tree by tapping it smartly, and, when thus isolated, its dislodgment is effected by inserting beneath it the wedge-shaped handle of the axe used in making the incisions. Occasionally the planks, after being cut out, are left to shed themselves, by the natural process resulting from the growth of the living bark beneath. The greatest care must be taken that the 3 A 2 724 CORK. incisions do not penetrate to the inner bark, or the life of the tree would be destroyed. The thickness of the cork layer thus removed is seldom less than f in. nor more than 3 in. According to the 23rd article of the laws regulating cork culture hi France, the minimum thickness at which the bark may be removed is 0'023 metre (say 0'9 in.); on the other hand, no good can be gained by allowing it to exceed the ordinary thickness, as the extra amount would only cut to waste. The freshly cut cork planks, or " tables," as they are called, have a natural transverse curve, corresponding with the shape of the tree from which they have been peeled. In order to flatten them, they are either heaped one upon another (with the concave side downwards) in deep trenches, plentifully moistened with water, and pressed beneath huge boulders ; or, simply placed with the convex side towards a fire, and kept there till the heat has removed the warp. Previously to this operation, the variously sized " tables " will have been reduced as nearly as possible to uniform dimensions of about 3J ft. long by 1 1 ft. wide. The next step has for its object the closing of the pores of the cork, as non-porosity is the quality which chiefly determines the value of the article. The finest kind is compact and firm, without being hard, of even texture or grain, and slightly pink in colour. The most common method of filling up the cavities in crude cork is by placing the tables before an open fire, and heating them till the surfaces are partially charred or singed, the heating being conducted with great care, and the sides changed constantly. The objection to this process is that it causes the secretion of an empyreumatic oil, which is given off, and may be taken up by any liquid with which it comes in contact. An attempt was made to avoid this eril by using young cork, whose texture was already so close as not to require heating ; but this was attended with little success, as the young cork was too thin for ordinary purposes, and could only be nsed by cementing several layers together. A much better plan, now often followed, is to boil the tables, scrape the surface, and then dry them in the sun. The pores are more effectually closed, and the sun-dried variety has none of the blackness of that dried by artificial heat. The "tables" are tied in bundles for transport to market. Cork is not the only product of the cork oak. The inner bark of the tree contains about 12 per cent, of tannin, whose properties resemble those of catechu rather than the tannin of most other Tegetable matters. It affords scarcely any of the light fawn-coloured deposit called "bloom," and it is doubted whether it is susceptible of conversion into gallic acid. It is not in favour with tanners, principally because it imparts a dark colour to leather on which it is used, and also because it yields no bloom. Its tannin is more easily extracted than that present in English oak bark, and, when used, it is generally mixed with the latter, or with valonea. Marseilles annually imports large quantities of it ; in Italy, it is almost exclusively used in tanning sole leather ; and, years ago, Ireland imported 8000 to 10,000 tons annually. It is only produced where the trees are most abundant, a its collection entails their destruction. (See Tannin.) The uses of cork among ourselves are pretty generally known ; but some of its applications where it is indigenous seem sufficiently curious In Spain, beehives, kitchen pails, pillows, and window lights are made of it ; in Pertugal, it forms the roofing of houses, linings for garden walls, and fences for poultry yards ; in Italy, images and crosses are carved out of it, footpaths are paved with it, and it is sometimes used in the buttresses of village churches ; in Turkey, it forms cabins for the cork cutters, and coffins for the dead ; in Morocco, it appears in the form of drinking vessels, plates, tubs, and house conduits ; and in Algeria, shoes and wearing apparel, saddles and horse- shoes, armour and boats, landmarks and fortifications, furniture, stable-racks, and doorsteps, all consume their share. In England, its greatest and most important application is the manufacture of stoppers for bottles and other vessels, which are always known as " corks." Until recently, these corks were all cut from the " tables " by hand, and, though several machines have been invented for the purpose, many are still manufactured by manual labour. The workman sits at a bench, which has a ledge round it, to prevent the corks falling off. The knife (Fig. 509), which has a very thin and sharp Hade about 6 in. long, tapering, and with a trun- cated end, is either placed edge uppermost in a notch on the bench, or is held in the hand. By a few dexterous circular cuts, the cork is turned out of the table, the size corresponding with the thickness of the latter. Wine-corks, &c. are cut across the grain ; bungs are cut with it. The Duchy of Olden- burg, in Germany, employs probably more hands in the cork cutting industry than any other country in the world, the yearly product amounting far into millions. The work is performed at home by the whole family, after the fashion of the tenement-house cigar makers. Prices vary, but SB. per diem is reckoned good wages; for the family to earn this sum, they must be skilled hands, and work hard for twelve hours. The spongy nature of cork necessitates that the edge of any instrument used to cut it should be brought into contact with it by a very drawing stroke, and the edge becomes dulled so quickly that it needs rubbing on a very fine-grained stone after every few strokes. CORK. 725 The chief obstacles in tlie way of employing machinery for cork-cutting are the rapidity with which the I leaf, and is less bright in appearance. / The best and most re- 1 gular of all the American Orleans .. .. 1-20 100 1-10 > 1 J cottons. Some lots are very white, but leafy; others of a creamy tone, but clean. Pernams 1-50 1-20 1-35 1 .. .. 1-40 1*10 1-25 f j mt 1-30 90 1-10 Ceara Aracati, &c. Paraiba .. 7. 1-30 1-30 1-00 1-10 1-20 1 20 Pernams to Maranhams are Brazilian cottons ; and, Brazil .., Santos ns a rnlo nro linr Vi ' Bahia Aracaiju, &o. .. staple, and give a wiry feel to yarns into whose Maceio .. .. 1*80 i-io 1 20 composition they enter. Maranhams.. ..j 1'30 1-30 1 00 90 1 15 1 10 COTTON MANUFACTUEES. 731 Country of Growth. Variety. Length of Staple. Mean Diameter of Fibre. DESCRIPTION. Max. Min. Mean. in. in. in. in. Egyptian .. .. 1-60 1 40 1-50 TT5TT Brown Egyptian is soft Gallini .. .. 1-50 1-20 1-35 and silky, whilst the Egypt .. brown .. M white is usually hard white and harsh. Smyrna Greek, &c I Harsh in staple, and cha- racterized by its irregu- larly twisted fibres. Fiji : Sea Island Tahiti : 1-90 1 25 1'70 Wery irregular in staple. West Indian . . | 1 60 1'40 1 30 1 30 1-20 1 10 1-45 1-30 1-20 Fair in staple, but cannot be relied upon through I successive seasons for I uniformity of colour. Haytian . . Laguayran Sea Island Exotic. rHard and soft varieties. Peruvian The soft assimilates with Soft Staple ,, ,. j Orleans ; the hard is best I mixed with Brazilian. Sea Island 1 ,, Exotic. A.fricd>n (Harsh-stapled cotton, not \ of a bright colour. The various classes under Surat ! 1-20 1 00 1-10 nW this head are fair working cottons ; but the fibre is \ 1'20 80 I'OO > not so uniformly twisted as in Americans. India.. Bengal .. .. 1-30 1 00 1-15 oW ( From Sea Island and Egyp- l tian seed. Eangoon .. .. Madras - rtn (Low in character; con- tains a large quantity of round and flat fibres. Cotton is valued according to the degree in which it possesses the special characteristics that best adapt it to the use for which it is intended. As its uses are multifarious, the raw material is classified in groups according to the probable wants of different consumers. The qualities chiefly con- sidered in classifying cotton are length of staple, fineness, strength, smoothness, colour, and cleanliness. American varieties are classed in four qualities : good ordinary, low middling, middling, and good middling ; South American, three : middling fair, fair, and good fair ; Egyptian, two : fair, and good fair ; East Indian, three : fair, good fair, and good. Standard samples of these classes are preserved for reference, in case of dispute, in the offices of the Liverpool Cotton Brokers' Association ; and it is customary amongst brokers to form a set of the classes in which they deal, and, after careful com- parison with the standards, to preserve them for easy reference when required. As, however, the crop of each succeeding year differs in some important respect from its predecessor, these standard samples are subject to considerable modification. According to the relative abundance or scarcity, fulness or deficiency, of special characteristics, the different varieties are classed up or down, as the cases may require. Thus, within a limited range, there is a constant fluctuation of the standard. The accompanying diagram (Fig. 515) shows the lengths of the staple in several representative varieties: 1: Sea Island, mean length of staple, I 1 65 in. ; 2: Egyptian, 1*50 in. ; 3: Pernambuco, 1-25 in.; 4: American, 1*10 in.; 5: Port Natal, I 1 10 in.; 6: Indian, 0'90 in.; 7: Indian, 0-65 in. It will be obvious, from what has already been stated, that considerable skill and discrimination are required in selecting the right qualities of cotton for any required description of yarn, as mis- takes cannot be rectified after the cotton has entered the first stage of manufacture. The mechanical structure of the cotton fibre is such that its perfect development has an important bearing upon its quality. As received in this country, mature or ripe cotton fibres, when placed under the microscope, present the appearance of irregularly twisted ribbons with thick rounded edges. The thickest part is the root end or base that which was attached to the seed. The diameter of the cylinder remains without material change, through probably three-fourths of the length, when it tapers off to a point. The accompanying illustrations admit of a comparison of the fibres of cotton at different stages of maturity. Fig. 516 exhibits a portion of mature fibre magnified ; and Fig. 517, suctions of the same. The latter show it to be a collapsed cylinder, the 732 COTTON MANUFACTURES. walls, as compared with the bore, being of considerable thickness. Fibres possessing these charac- teristics are longest and strongest, and are considered well developed. But amongst the perfect fibre, there is always more or less of unripe, imperfectly developed, or dead, fibre, according to the favourable or unfavourable conditions that have prevailed during the growth of the plant. The proportion of defective fibre naturally present is always largely increased by the practice, on the part of cotton growers, of collecting the immature pods on the cotton plant, after the latter has been killed by frost, or, from other causes, has ceased to grow. These are dried, and their lint id stripped from them, and added to the bulk. The appearance presented by the unripe fibre is greatly diflvrent, both longitudinally and in sectioii, from that of the mature. In Fig. 518, the half-ripe fibre is shown longitudinally ; and in Fig. 519, in section. The least ripe form in which cotton usually appears in commerce is depicted in Figs. 520 and 521. Though twisted almost as much as the perfect fibre, this last is thin, weak, and brittle; and, owing to the de- ficiency of cellulose, of which the walls of the mature fibre are composed, it is destitute of the corded edges seen in the latter. In sections, it appears like crooked bits of fine wire, showing little or no vestige of having been a hollow cylinder. When these defective fibres are found in great abundance, they seriously detract from the work- ing quality of the bulk; and it is an important matter, in judging of cotton, to be able to dis- tinguish them. This may be acquired by careful observation. In relation to these faulty fibres, the greatest circumspection needs to be exercised, in the seasons when the plant, with its load of bolls in all stages of growth, has been struck down by an early frost, for all the bolls are care- fully gathered, and their contents abstracted, and mixed with the perfect lint. The convolute form of the cotton fibre specially adapts it for its manifold uses. If it were cylindrical, like the fibres of flax and hemp, its shortness would prevent ita holding together. But from their peculiar form, when twisted in the process of spinning, the fibres become firmly interlocked, by which means they may be made into a continuous thread, of considerable tenacity. When the finest varieties of cotton are employed, this thread is capable of remarkable attenuation. Lint gathered from the unopened or unripe pod, does not show these twistings in the fibre ; hence it is incapable, when spun into yarn, of affording the same cohesive power, and produces defects wherever it occurs. The convolutions in the dif- ferent varieties of American cottons are more regular, uniform, and numerous than in those of other descriptions, and fully account for their acknowledged superiority. The naked eye is in- capable of distinguishing these twists; but the microscope shows them to amount to from one to three hundred an inch, and close examination would probably show even a wider range than this. Many theories have been broached, and much ingenuity expended, in the attempt to explain the nature of this peculiarity of the cotton-fibre the manner in which it is twisted upon its own axis. This point cannot be dilated upon here ; but it may be permitted to put forward very briefly what appears to be a simple and natural explanation of the fact. It is known that fibres taken from unripe and unopened pods are invariably untwisted cylinders, tapering to a point at their COTTON MANUFACTUEES. 733 extremity, which is closed. They have their root in, and receive all their nutrition from, the seed. Whilst in a growing state, the fluids of the plant circulate freely therein, conveying to every part the necessary amount of nutritive matter. When maturity is attained, this operation ceases : the juices are probably absorbed by the seed, and as they retire from the fibres, a vacuum is formed, first near the extremity, and subsequently along the length of each fibre, to its base at the junction with the seed. The pressure of the atmosphere, acting upou this vacuum where it is first formed, causes the tube to collapse and twist, from its apex downwards to its base. The seeds of each pod, ripening simultaneously, set rap a commotion in the interior of the latter, by the general collapse of their fibres; and the consequent re-arrangement of these, in relation to each other, causes the pod to burst, when the desiccating action of the sun's rays expedites and completes the process. A further elucidation of this theory shows that it satisfactorily explains the whole phenomenon ; and though perhaps of no great practical utility, it is not without interest, as it appears to have engaged the attention, and to have baffled the penetration, of previous writers on the subject. MECHANICAL TREATMENT OF COTTON. As a preliminary to a detailed description of the pro- cesses and machinery used in the various stages of the treatment of cotton, for the production of yarn, and afterwards of textiles, the subject will be rendered more easily intelligible by drawing up a scheme representative of the general procedure ; this will also afford an opportunity of defining the principal technical terms used, and will remove any confusion arising from their occasional employment in wide, restricted, or otherwise varying senses. Cotton Spinning. This term, as previously indicated, is employed to describe in the aggregate all the operations involved in transforming raw cotton into yarn : that is, into a single twisted strand, or thread composed of cotton fibre. The word "spinning" has also a more limited signification, being used to denote, as will subsequently be seen, the concluding process of the series. The manipulation, mechanical and otherwise, that cotton undergoes in being converted into yarn, from the state in which it is gathered from the plant, may be outlined as follows : 1. " Ginning." This is usually performed in the vicinity of the cotton plantation ; the object being to remove the fibre from the seed of the plant, and partially to cleanse it from foreign matters. 2. " Packing" or " Baling." After ginning, the lint is in a loose state, and unfit for convenient 734 COTTON MANUFACTURES. transport to distant markets . hence it is necessary to compress it into less space, which is ordinarily performed by means of hydraulic presses. The package leaves the press in the well-known form technically called a " bale," in which state it passes through the markets into the hands of the spinners. 3. "Mixing." Is the blending of different varieties of raw cotton, in order to secure economical production, uniform quality and colour, and an even thread, in any desired degree. Mixing is, in a measure, imperatively necessary, in order to neutralize the irregularities of growth, and imperfect classification, found more or less in all cottons. It is the first operation in a cotton mill. 4. " Willowing." This is a process of opening and cleaning cotton, which, except in the Oldham district, is not much used in modern mills, and is retained chiefly for opening and cleansing low cottons, waste, &c. 5. " Opening " In consequence of the heavy pressure to which cotton is subjected in packing> the fibres become strongly matted together ; the opening process is to loosen them, and to remove a portion of the foreign substances present. It is the present equivalent of willowing. 6. "Scutching." Has a twofold object: viz. the further extraction of impurities, and the formation of a " lap," which is a web or sheet of cotton formed in the machine, and wound upon a small roller. In this web, the fibres lie in all directions. 7. " Carding." The foregoing processes have dealt with the cotton in bulk. In carding, the operation of opening is continued ; but the material is treated in its individual fibres, which are taken from the lap, further cleansed, and laid in a position approximately parallel to each other, forming a thin film, which is afterwards condensed into a " sliver " a round, soft, and untwisted strand of cotton. 8. " Combing." Is used for the production of fine yarns, or those of very high quality. Its object is to obtain uniformity in the length of the fibres undergoing preparation ; to accomplish this, all those shorter than the required standard are combed away, and rejected. 9. " Drawing." In this operation, several slivers, the product of the carding process, are combined, and attenuated to the dimensions of one of the component parts; the objects are to render the new sliver more uniform in thickness, and to place the fibres more perfectly in parallel order. 10. " Stubbing." Is a process by which a further combination of the slivers is effected, and the objects of drawing are more perfectly accomplished. The drawing or attenuation of the strand is now carried so far that it becomes necessary to twist it slightly, in order to preserve its cohesion, and rounded form. 11. "Intermediate" or "Second Slubbing." Is in all respects a repetition of the above; necessary in cases where the most even and clean yarn is required. It is not ordinarily used in the production of low numbers. 12. " Roving." This is a continuation of the preceding, its principal object being to still further attenuate the sliver. At this point, also, the latter receives additional twist, to enable it to bear the slight strain necessary to draw it from the "spool," without the formation of uneven places. 13. " Spinning." The concluding process of the series. The sliver is here attenuated to the required fineness, and is given the twist by which the thread is completely formed. 14. " Doubling." In this series, may be included the process of doubling, it being much more akin hereto than to manufacturing. It is a large and increasing business, often carried on in conjunction with spinning, but frequently found quite apart. It is a method of combining two or more threads to form a single cord ; and is adopted in the production of many varieties of yarn, which are used for widely different purposes. The above processes, and the machinery necessary thereto, will be described in the order given, excepting, however, the first two, which will be dealt with in treating of the production of the raw material (see Fibrous Substances). In performing this task, it is not intended to allude to obsolete methods and machines, unless such reference will tend to elucidate the principles on which the modern system is based. Even with this limitation, it will not be possible to make a general reader acquainted with every variety of machine that has met with, and still retains, a certain amount of favour. The Cotton Mill. The considerations that influence the ^election of a locality in which to erect a cotton mill are chiefly the following : Firstly, proximity to an abundant store of cheap and good fuel ; secondly, an unfailing supply of water, or means of preserving it ; thirdly, easy an>l cheap means of access to the market, by road, water, or rail > and, fourthly, an area within which an experienced class of operatives can be obtained. There are several other minor points, but they need not be detailed. As many as possible of these conditions should be found in the locality selected, as all are highly important, and greatly conducive to success. The choice of site should be carefully considered. A valley, protected from dry winds, and open to moist ones, is of great advan- COTTON MANUFACTURES. 735 tage. The subsoil shou'd be of stiff, impervious clay, such as will retain the moisture in a subter- ranean reservoir, the evaporation from which will be constantly moistening and softening the atmosphere advantages that have been previously explained. The fittest materials for the structure will be dictated by the circumstances of the locality ; but in the presence of the conditions prescribed above, brick will generally be found most suitable and economical. Should it be requisite to provide a reservoir for water, any clay excavated for this COTTON MANUFACTURES. purpose, as well as from the foundation trenches, can be utilized for the manufacture of bricks- The methods of construction are various. The one formerly common and, perhaps, even now cheapest in first cost was a combination of brick or stone with timber. Another is the so-called "half fireproof" plan, in which that portion most liable to destruction by fire until recently, considered to be that in which the preparatory machinery is worked is constructed as far as possible without timber. 523> But of late years, owing to the high speeds attained, the danger has extended to the mule-room. This experience has given rise to the most modern, and now generally approved, system, in which the whole structure is fireproof. There are several ways of attaining this end. The mill shown in Figs. 522, 523, and 524, from drawings kindly furnished by A. H. Stott and Sons, mill architects, of Manchester and Oldham, is thoroughly representative of recent constructions, such as prevail in the great spinning districts of South Lancashire. The dimensions of the main portion of the structure would be about 295 ft. by 125 ft., accommodating 75,000 spindles, and the usual complement of machinery in connection. The foundations are of coarse rubble, on 1 ft. of mortar concrete. Those on which the columns immediately rest are of flag-stones. The walls are composed externally of pressed brick, and internally of common brick. The window-sashes are of wood, glazed in the lower part with rough plate, and in the upper with clear glass. The floors are supported upon cast-iron columns, in which brackets or arms are cast. To these are secured rolle I iron beams, the object being to get two arches in place of one. Each pillar bracket is connected with the next by an arch beam, to form a complete continuation between the pillars and the direction of the bracket. The brick arches are 7 in. thick at the base, diminishing to 4 in. at the crown ; they are turned between the beams. Timber joists, 2 in. deep, are then laid across the beams, and the space is after- wards filled up with concrete, composed of lime and furnace ashes. When this is thoroughly dry, the floors are laid with IJ-in. deal boards, nailed to the joists. Boarding is now generally preferred for all room floors, except the blow- ing-room. The floor of the cellar is composed of bricks, laid on puddled clay, with passages formed of cement concrete, or flag-stones. The roof of the mill is, in the first place, constructed in the same manner as the floor ; but the concrete is laid level, and then covered with two coats of asphalt, each J in. thick. These are turned up the wall, 18 in. all round, and protected from the weather by a dwarf brick wall, built inside on the asphalt. Constructed thus, the roof forms a reservoir, containing 6-12 in. of water. The object of this is to render it thoroughly fireproof. In some cases, 12-18 in. of water is preserved, and arrangements are made for utilizing it at a moment's notice in the event of fire. When this plan is adopted, conduit pipes are laid to, and around, the interior of each room, and provided with the necessary taps. The staircase is composed of stone, with cast-iron risers. The roof of the engine-house is fireproof, and supported on large rolled-iron girders ; that of the boiler-house is of ordinary construction, provided with ventilators. The chimney rises to a height of 210 ft; its diameter at the bottom is 17 ft. externally, and 8 ft. internally; at the summit, it is 9 ft. 10 in. externally, and 7 ft. 6 in. in- ternally. The arrangement of the mill is as follows : The ground flnor contains the blowing-room, carding-room, warehouse, offices, and entrance lodge. Over the carding-room, are three spinning- rooms, of equal dimensions. Above the blowing-room and warehouse, are situated the mixing-room for cotton, and store-rooms for sundries. Partinlly over the mixing-room id the bale-room, provided COTTON MANUFACTUKES. 737 with a door opening on the end of the mill, and fitted with a self-acting hoist. Level with the bale- room is the reeling-room, and over these is a twining- or doubling-room. The boiler-house at the back of the mill contains five Lancashire boilers, 30 ft. long and 7 ft. diameter, each having two circular flues, 2 ft. 9 in. diameter at the firing end, tapering to 2 ft. 4 in. Behind the fire are in- serted six Galloway tubes. The boilers are fed with water from the hot well of the engine. Behind each boiler, is fixed a fuel economizer, of ten pipes width : in all, 360 pipes. Passing through these, under the influence of the waste heat from the furnaces, the water attains a temperature of 138 (280 F.), before reaching the boilers. The latter are usually worked at a pressure of 90 Ib. The engines are of the tandem type, with low-pressure cylinders in front, and high-pressure behind, on the same piston ; the former are 40 in. diameter, the latter 21 in. The stroke is 6 ft. The air- pump is situated under the slides of the piston-rod, and is worked by a bell-crank motion ; it has a stroke of 3 ft. The condenser stands by the side of the air-pump. The ordinary vertical type of the latter is still the most popular amongst practical men. The fly-wheel is 30 ft. in diameter ; its periphery is 5 ft. 6 in. broad, and is grooved for the reception of 23 ropes. The grooves are V-shaped, and of such a depth that the ropes do not touch the bottom. The ropes are of hemp or cotton, and are made in different ways. In the centre of, and extending around the periphery, are cast a set of cogs, for barring it round ; these can also be used for moving it by a small bar-and- ratchet arrangement. Power is transmitted directly from the engine to each compartment of the mill, by means of the above-mentioned ropes, which are received by a grooved drum, fitted upon shafts that extend throughout the length of the mill. In the carding-room, the central shaft, driven from the engine, is turned by five ropes, and makes 220 revolutions a minute. Two other shafts, one on each side, run parallel with the former, and are driven from it, by ropes, at the same speed. The shaft nearest the rear of the mill supplies the motive power to the carding-engines ; the middle shaft, to the drawing-frames, slubbing-frames, and intermediates ; whilst the one farthest from the engine drives the roving-frames, the willows, and the openers. In the spinning- rooms, the shaft driven by the engine extends throughout the entire length, and makes 220 rev. a minute. In the top room , a shaft is carried over the warehouse part, and drives the twining-jennies. The bale-room, which receives the raw cotton, as it is hauled in from the mill yard by means of the automatic hoist, is pro- vided with openings in the floor, bound with cast-iron frames, having covers of the same material. Similar provision is made in the mixing-room, for passing the raw material to the blowing-room. At the corner of this room nearest to the chimney, is a dust-flue, for carrying away the dirt and sand separated from the cotton by the willows, openers, and scutchers. The machinery is arranged with a view to rendering the processes consecutive, and to incurring the least possible cost for handling the cotton as it passes through. For a mill of the dimensions indicated, 2 willows and 2 openers are required to serve 12 single-beater scutchers. These provide laps for 54 double carding-engines, 50 in. on the wire. Sufficient sliver is produced from these to supply 9 drawing-frames of 3 heads of 6 deliveries each ; which, in their turn, serve 9 slubbing- frames, of 80 spindles each : whilst the latter give full employment to 12-13 intermediates of 124 spindles each, the production of these being taken by 40 roving-frames, of 168 spindles each. In a mill spinning 32's warp yarn and wefts to correspond, the above-named preparatory machinery suffices to supply the complement of spindles, about 70. 000. Twining, or doubling, is a subsequent process. Mixing. The raw material received into the bale-mom is examined by drawing samples from 3 B 738 COTTON MANUFACTURES. different parts of each bale, and is classified accordingly. This step is necessitated by the fact that the quality of cotton gathered at different periods of the picking season is subject to material variation. Errors of classification and warehousing may produce a better or worse quality than the purchaser intended, or mistakes may be made in purchasing, from unfamiliarity with the needs of the establishment. These are sources of error to be guarded against. When the quality and magnitude of the mixing have been decided on, the classified stock is drawn upon ; the coverings are stripped from the bales, and the contents are passed in succession through the apertures in the floor to the room below, and spread upon the floor, in layers occupying a fixed area. Some- times this space is railed off from the room. The " mixing " will be composed of us many layers as there are bales, these being taken in that order which will best enable their qualities to contribute to the end in view. When the mixing is completed, it is usual to test the result, by taking a vertical section of the blend raked from the face of the pile , sufficiently large to manufacture into yarn ; this is carefully examined, and compared with a standard yarn, or with that from the last mixing. Should it be deficient in strength, cleanliness, or colour, a sufficiency is added of the raw material possessing the requisite quality. Sometimes the testing is repeated, especially when the quality is intended to be high class, and it is desirable to run no risk of deterioration ; in other cases, the blend can be made so near the requirement, that it is not considered necessary. In low qualities, and admixtures of waste, the testing process is sometimes neglected ; but in a well regulated establishment, it should never be omitted. The satisfactory condition of the blend having been ascertained, it is ready for use. When required, it is carefully and evenly drawn down from the sides of the pile, by means of a rake ; this ensures a further intermixture of the qualities. The component parts of the blend will necessarily differ according to the quality of yarn sought to be produced. Experience will enable cotton-spinners of average skill to prescribe mixings with great accuracy ; but there is nothing like uniformity among them in this respect, many affecting to keep the particulars secret. The following Table, however, very kindly furnished by John Butter- worth, of Shaw, near Oldham, one of the most scientific and skilful spinners in Lancashire, shows, in a general manner, the adaptability of certain cottons for spinning different numbers of yarn, and their suitability for admixture with each other : Best Sea Island Soft \ Best Egyptian, and Shortest Sea Island Peeler (American), and Egyptian Orleans, Texas, and Soft Peru- vian Pernams, Paraibas, Maran- hams, Maceio, Rough Egyp- tian, and Rough Peruvian .. Puerto Cabello (W. I.), Suri- nam, and Brazilian Peruvian La Guayran (W. I.), Ceara (B.), and Aracaju (B.) Dhollerah, Dharwar, Broach, Oomrawuttee Smyrna, African, Persian Comptah, Bengal, Madras, Rangoon These two classes are mixed together, as the abundance or scarcity of each class prevails; but it is found that rough and smooth staples do not incorporate well, and hence do not make the best yarn. The lower classes of American are often mixed with these varieties. Georgia, Boweds, &c., mix best with Dhollerah, Broach, Oomrawuttee, &c. ; but stronger kinds are often used. The strong low classes of American are best adapted to mix with West Indian, Rough Brazilians, Smyrna, African, 120's upwards. 80's to 120's. 60'sto 80's. 40'sto 60's. 40'sto 50's. 30's to 40's, 26'sto 36'B. IG'sto 28's. 10'sto 16's. very low numbers. Several varieties not named above would mix with one or other of the classes ; but special adaptations must be left to the discretion of the spinner. At this point, it may be well to explain the significance of the figures in the third column of the above Table. Yarns are always quoted by the pound, the price differing according to quality and fineness. The latter is indicated by numbers, from 1's (one's) upwards; the limit of fineness in the mercantile article is about 300's (three-hundred's). These numbers are arrived at in the following manner : In the early days of the trade, when yarns could not be spun with the regu- larity that can be accomplished at present, uniformity was secured by reeling the yarn, and assorting the hanks according to weight. The circumference of the reel was 1J yds., and the 80th revolution was indicated by a rap from a released spring, the length then wound being 120 yds., or 1 " lea." When 7 leas had been wound, they were tied together, forming 1 " hank,'' or 840 yds. The number of these hanks in 1 Ib. indicates the fineness of the yarn, which is expressed thus 4's, 12's, 206, 32's, 40's, 60's, &c., &c., to 300's. From the lowest Nos., it is customary to rise 1 hank at a time, up to 10's; thence steps of 2 hanks are generally taken, up to COTTON MANUFACTURES. 739 24's ; then 4: hanks at a rise, up to 40's ; after this, the gradation, though sometimes 5, is generally 10 at a step. Any Nos. between these would be special, and would require to be spun to order. Cotton yarns are always bought and sold by avoirdupois weight; but, in ascertaining the counts or Nos., it is necessary to subdivide the pound into Troy grains, of which it contains 7000. The measure employed is as follows : 54 in. = 1 thread (or circumference of reel). 4320 = 80 =1 lea. 30240 = 560 = 7 = 1 hank, or 840 yds. To ascertain the counts of a yarn, 7000 is divided by the weight (in grains) of one hank. It is customary, however, to take a proportionately less quantity, say 1, 2, or 3 leas, the dividend being ]UOO, 2000, or 3000 accordingly. The quotient is the number of hanks in 1 lb., hence the No. of tlie yarn. Opening. This process follows mixing. It is performed by the aid of various machines, according to the requirements or the preference of the spinner. The principal are the following : The willow, the Crighton opener, the Porcupine, and Lord's opener. The common, or Oldham, willow (Figs. 525 arid 526) consists of a cylinder c, about 40 in. in diameter and 40 in. wide, mounted on a shaft, furnished with driving pulleys, and resting oa bearings in tlie framework. Fitted on, and extending across, its periphery, are several rows of teeth, or blunt spikes. A semicircular casing, in- ternally furnished with two or three rows of spikes similar to the above, covers the upper part of this cylinder. The lower portion is covered with a wire grid, in two parts, hinged to- gether. The back section of this is fixed to the frame, whilst the front part is balanced by weights, suspended from cords or straps, passed over pulleys at each side, and attached to the end of the grid, which is free to move up and down in an opening in front of the machine. An exhaust fan / is placed behind the fixed part of the grid. The operation is as follows: The grid is let down, and a quantity of cotton is placed upon it. It is then raised, and the cotton is thus brought 626 into contact with the spikes of the re- volving cylinder, which dash it against the fixed spikes on the internal face of the casing, loosen- ing its matted fibres, and freeing it from sand, dust, and other foreign matters, which fall through the grid into the cavity below, or are drawn away by the operation of the exhaust-fan, and dis- charged through a tube into the air. After the cotton has been subjected to the action of the machine for a few seconds, the grid is let down, and the cotton is thrown out. The process is then repeated with fresh material. This is the simplest form of the willow as it exists in use. The willow-, however, has lately undergone great improvements. It is sometimes made with an automatic motion, to let down the grid when the cotton has been in the machine for the proper length of time, which can be varied according to requirement. At other times it is made con- tinuous, as seen in the figures, by placing a feed cloth a in front, and a lattice creeper e at the back, to carry away the cleansed cotton, which is then ready for delivery to tlie scutcher. The second machine mentioned above, the Crighton opener, which is now in extensive use, is a modification of the cone willow. As will be seen from the accompanying illustrations, Figs. 527 and 528, in the interior of the framework, is fitted a conical grid, having its apex downwards, and resting on a cross-rail at a short distance from the bottom. On the top of the frame, stands a tripod, which forms a bearing for a vertical shaft, carrying driving pulleys, and descending through the centre of the grid to a foot-step in the cross-rail. Mounted on this shaft, are a number of discs b, smallest at the bottom and increasing in size as they approach the top. Fixed on these, are a series of thin steel blades, for beating the cotton. At the top of the grid, is an orifice conducting to the dust- cages. The space c, between the casing and the grid, forms a cavity for the reception of any foreign matter contained in the cotton. The machine is fed by means of the tube a, which may 3 B 2 740 COTTON MANUFACTURES. be introduced on any side away from the attachment. The latter includes the dnst-cnges, fan /, lattice-creeper d, and, below the dust-cages, a pair of small delivery-rollers, and an exhaust-fan. The cages are hollow cylindrical wire frames, with the wires set sufficiently close to prevent the entrance of the fibres of cotton, but wide enough to permit the dust to be drawn away by the current. Only the portion of the cage opposite the orifice 52I? - is left open, the remainder f , being closed by an internal casing, which follows the contour of the cylinder. The details of the process are : The cotton is fed into the tube a, emerging into the lower portion of the conical grid, where it comes into con- tact with the beaters b, which strike it against the bars of the grid. This action loosens the mass of fibre, and permits any seed that may be in the lint, as well as sand, dust, &c., to fall through the grid into the dust-cavity c, and thence to the bottom e. The cotton remains subject to the action of the beaters, until it is opened sufficiently to admit of its being drawn up- ward, and carried away by the suction of the fan /, through the orifice. Fol- lowing the direction of the arrow towards the dust-cage, it is taken on by the rollers, and passed to the lattice- creeper d, which discharges it upon the floor, or into a receptacle provided. This machine has also been improved by the addition of an automatic feed or lattice apron, and a lap machine. By some, its action is regarded as being gentler, and less injurious to the cotton, than that of the willow, through its possessing no stationary teeth to intercept the progress of the fibre ; also by its peculiar structure, which causes it to retain the cotton until thoroughly opened, but not longer, thus avoiding excessive beating. The " Porcupine " is another opener, whose chief difference from the willow as illustrated above lies in the possession of two cylinders for opening purposes, laid parallel to each other, the first of which has twelve rows of teeth, and the second four. It is fed and discharged by lattice-creepers, and exhausted by the usual appliances. Lord's combined opener, scutcher, and lap machine, is a remarkable illustration of the manner in which several processes may be concentrated in what is practically one machine. The inventors largely avail themselves of the pneumatic principle seen in each of the previously described openers, and use a current of air to bring the cotton from any moderate distance. As will be seen from Fig. 529, which represents the feeding as taking place in the room above the machine, an endless lattice A, on which the cotton is evenly laid, delivers it to two pairs of rollers B, the second revolving more quickly than the first ; these convey it to the tube, where it is instantly seized by the air current. During its aerial passage, sand, dirt, dust, small stones, and all heavy or dangerous substances accidentally present with the cotton, are dropped upon the bottom of the tube. In order to secure the abstraction of these, Messrs. Lord invented and patented their grated trunks. Intermediately between the feed table and the opener, several lengths of these tubes C are inserted. Seen in section, they are Q shaped. Inside these, at short distances apart, plates of sheet iron are placed athwart, and slightly inclined against the direction of the current, and reaching about half-way to the crown of the tube. The spaces between these plates form cells for the reception of extraneous matter, which, dropping out of the cotton, is retained in them ; it is removed daily through the bottom of the tube, which opens downwards, and is hinged for the COTTON MANUFACTURES. 741 purpose. These cells prove very efficient, as is shown by the quantity of dust that is taken out of those in the front, and its gradual diminution towards the last ; and by the small amount of foreign matter thrown off in the opener and scutcher. The opener consists of a horizontal shaft a, carrying a series of accurately balanced arms d, arranged radially on the shaft at several inches apart. These arms are of cast iron, with steel blades bolted firmly to their extremities. The length of these arms is, at the small end nearest the tube, about 18 in. ; it increases gradually as the opposite side is approached, terminating with 28 in. When revolving, the arms describe the figure of a cone. A conical grid surrounds the beaters, constructed by the junction of two rings of unequal diameter by means of straight steel bars. This grid can be moved endwise upon the shaft, by means of the wheel beneath the tube, at the left extremity of the machine. The bars are fixed at the delivery end, but are capable of adjustment at the feed end, in order to increase or diminish the distance from the beater, according to the length of staple or quality of cotton that has to be treated. On the same shaft, at the delivery end of the beater, is a powerful disc fan, which, in conjunction with the other fan p, whose specific function is to exhaust the dust-cages //, and which is situated below them, draws the cotton from the extremity of the feed-pipe, through the beater, to the dust-cages ; at this point, the cotton is received by two small rollers, that deliver it to the beater g of the scutcher, where it undergoes further opening and cleansing, by a process resembling the one it has juat passed through, except as regards the form of the beater. The scutcher and lap attachment, which receives the cotton at this point, will be described in connection with the next machine. Scutching. Scutching has a twofold object : to further cleanse the cottou, and to form a lap. If the raw material has not, in the previous stage, passed through an opener with a lap-forming attachment, it arrives at this point in bulk, and but partially cleansed and opened. Scutching is the first stage in the series of arrangements that produce the finished article. The lap is a continuous sheet of cotton, about 40 in. wide, which is formed into a roll of convenient length to suit the machinery. In it the fibres lie in all directions across each other, no attempt having yet been made to arrange them in parallel order. The scutcher has undergone many changes ere attaining its present comparative perfection. Amongst makers, the result is unanimity regarding the main features of the machine, tempered by differences on points of detail. The latter need not be brought fully before the reader: it will serve to describe one or two of the most popular and representative forms. The Crighton scutcher is a well-known machine. It possesses a lattice-creeper, on which the cotton is evenly laid, in measured spaces, after being weighed. A pair of small fluted rollers take the cotton from the lattice, and pass it to a beater, having two blades encased in a cylinder ; a quarter-section of the latter, from the fluted rollers to the bottom, is composed of a grid. The beater, having a speed of about 1000 revolutions a minute, strikes the cotton with great force from the rollers against this grid, causing leaves, motes, and other impurities, to fall through. Parallel with the bottom of the cylinder, is a passage, leading to the pair of dust-cages situated at the back. Along this, the cotton is drawn by the current induced by the exhaust-fans. The bottom of this passage is formed by a lattice, arranged with its surface open, for the reception of impurities that may 742 COTTON MANUFACTUEES. have passed the first grids. This lattice moves over three rollers arranged thus . , and, travelling in a direction opposite to that followed by the cotton, it carries away only substances of greater specific gravity than the fibres under treatment, and discharges them into the dust-cavity beneath tie grid. The loose cotton is evenly distributed by the current over the wires of the dust-cages, as they slowly revolve. These wires, whilst holding the cotton, permit the extraction, through their interstices, of the fine particles of dust that may have come on the current of air along with the fibre, hence their name. The perfect removal of saud or grit is of great importance, because were it to pass along with the cotton through subsequent processes, it would seriously damage the machinery. The cages join the cotton deposited upon them into one sheet, which is removed by a pair of small fluted rollers ; these pass it to the compression-rollers, whence it escapes to the lap- roller ; this, by means of a pair of large fluted rollers, revolving in the same direction, takes on the sheet of cotton until it has formed a thick roll, technically called a " lap." From the first handling of cotton in the mill, the object is to obtain a clean, round, even thread of yarn. In order to secure this, it is necessary that the scutcher or first lap machine should be carefully fed, the cotton being spread evenly upon the lattice, so that it may pass through at a uniform rate. But it is not always possible to ensure this with hand labour, and mechanical appliances have in consequence been invented for the purpose. The most popular, and reputedly the best, of these is the one introduced by Lords, and called the " lever-" or " piano-feed " motion, from its being in principle similar to, and in figure distantly like, the arrangement of the keys of a pianoforte. Fig. 530 will help to explain its details. Fig. A shows it in section : a represents the beater, the dotted line tracing the circle which its blades describe hi their revolution. Instead of a pair of feed-rollers, as usual for delivering the cotton to the beater a, the bottom one is replaced by a series of levers c, extending across the frame, arranged as in Fig. C. In B, is shown a different form of the short end c of the lever, adapted for long-stapled cotton. By means of a hook at the extremity of the lever-arm e, the levers are attached to rods/, which increase in thickness at the end where they pass between two horizontal plates or bars g, laid parallel on the back and front of their pendant extremities. In the interstices, small bowls are introduced, shown by the dotted circles . The rod /, on the right, is slotted for the reception of a connecting-rod attached to the levers, the second of which is connected with the strap-lever p, seen between the cone-drums in Fig. 531. A sector wheel, on the strap-lever />, gears into a similar one on the strap-lever p l ; q,r are cone-drums, and s is the strap by which motion is transmitted from one to the other. The action of the different parts is as follows : When the cotton is matted, or unevenly spread upon the lattice, causing a thick portion to go beneath the roller 6, the short end of the lever c is pressed down, the long arm e is raised ; this pulls up the rod /, the thick end of which, coming up between the bowls ', presses the rods in the only direction in which they can move towards the slotted rod at the end, which, through the connecting-rod and levers above described, moves the strap s upon the cone-drums q and r, and regulates the speed according to requirement; the cone- drum r gives motion to the feed-roller 6, through the worm on its shaft. This has proved to be a very efficient arrangement, and has been extensively adopted. It can be attached both to the first and second scutcher. Lord's finisher lap machine, with the " piano" feed attachment, is illustrated in Fig. 531. The COTTON MANUFACTURES. 743 Creel holds from four to six laps n, which, by means of the lattice x, revolving on the rollers at each extremity of the creel, deliver a three, four, or sixfold sheet of cotton to the feed-roller 6; this, by means of the evener, or piano feed, just described, is made to deliver its burden to the beater a, at a uniform rate. The bottom of the beater case A contains a grid d, whilst a longitudinal grid d l extends to the dust-cages v. At C, the casing is usually glazed, or a doorway is formed, in order to permit inspection of the interior. Glazing is preferable, as a doorway interferes with the action of the exhaust draught. Next to the dust-cages, are the compression-rollers w, through which the cotton passes to the fluted rollers 2, at the end of the frame, which, slowly revolving, wind it upon a roller, called the " lap-roller." When the lap y is completed, it is lifted from the frame, and laid aside, and the roller is withdrawn, and replaced to wind on another lap. The soft mass of cotton quickly closes up the space left by the withdrawal of the roller ; and ordinarily, when the lap has to be skewered, for placing in the carding-engine, considerable difficulty and waste are the result. In order to obviate these drawbacks, a plan has been devised and patented by H. H. Clayton, manager of Kingston Mills, Hyde, which is thoroughly successful. In place of the solid lap-roller, the inventor substitutes a tube-roller, into which he inserts a long pin, having a flat head, of greater diameter than the roller. When the latter is withdrawn, the pin is left in the cavity, retained by the head, thus preserving the bore, maintaining the form, and facilitating the handling of the lap, whilst time and labour are economized, and all waste from the " stabbing " of the lap is prevented. The process through which the cotton passes is very similar to that in the compound opener previously described. The draught of the feed upon the laps in the creel is very slow, and stands in remarkable contrast to the action of the swiftly revolving beater. The exhaust-fans also revolve very rapidly, whilst the dust-cages move at a slow pace, in order to allow the draught to deposit a thick sheet of fibre upon the exposed portion of their surfaces. The finisher lap machine is used for the purpose of completing the cleansing process, and obtaining a uniformly level lap, by doubling the laps from the scutcher. The idea which suggested the latter plan is to some extent erroneous. The assumed result would be achieved if it depended solely upon mechanical influences ; but to these is closely allied a pneumatic force, which greatly modifies the process. The cotton, after passing the beater, is drawn by the current from the fans to the dust-cages ; upon the exterior of these, it is accumulated, until the layer becomes impervious to the air, when the cotton ceases to be drawn to that spot, and is diverted toother portions of the cages, where the draught is still exerting its influence. An even delivery of the cotton may aid, but will not necessarily secure, the formation of an even lap, as the latter will quite as much depend upon the uniform strength of the current over the exposed surfaces of the cages. Should this vary appre- ciably in any portion, the lap will be thinner there than elsewhere. The pneumatic principle is dispensed with in all machines subsequent to the finisher lap machine. Carding. This is one of the most important processes in cotton-spinning. The object of those preceding it has been to cleanse the raw material from gross impurities, such as leaf, seed, sand, dust, and heavier objects, that may accidentally or otherwise be introduced. Carding is the final stage of cleansing. As far as the carding-engine is capable of accomplishing it, all short, tangled, and " neppy " fibre is removed in this operation. To make clean yarn, cotton should be selected free from immature seed, which the gin often fails to remove, owing to defective seeds being so small as to pass its blades, and get drawn in by the short and imperfectly developed fibre that covers them. Neither opening nor scutching abstracts them completely, and those that escape pass into the card, and are broken up. The particles are carried through the succeeding operations without being markedly visible, until the spinning is reached, when the twining brings them to the surface of the thread, where a great proportion are retained by the adhering fibres. In other respects, the cleansing function of the machine is very eflBcient. 744 COTTON MANUFACTURES. In carding, the construction of the thread is commenced. Up to this point, there has been no effort to arrange the fibres in any given order. Here the attempt is first made to place them parallel. The thick sheet of cotton composing the lap is reduced to a thin cloud-like film, which is drawn through a cone tube, and condensed into a " sliver," a round, soft, and untwisted strand of cotton. The carding-engine is the machine by which this is accomplished. Some difference of opinion exists amongst practical men as to the best principles of construction, and in consequence there are several forms of the machine. Good arguments can be adduced in favour of each, and probably tke diverse opinions that exist originated in dealing with different classes of raw material, and getting various results. To trace the development of the card would be interesting, but would need a volume for its elucidation. All that is necessary is to describe representative forms as now in use. Of these, there are three : the roller, the Wellman, and the revolving flat card. A section of the roller card, with a portion of the side, is shown in Fig. 532. Its chief parts are the following : A, main cylinder or swift, which has a surface speed of about 1600 ft. a minute ; the roller B is termed the " licker-in," from its function of taking the cotton from the feed-roller 0, and delivering it to the swift. The small cylinder D is the doffer ; E, the coiler ; F, the can in which the sliver is coiled ; and G, the lap, resting upon G', the lap-roller. Arranged over the main cylinder, are a number of small rollers, r and s. The former are carding rollers or " workers " ; the latter are " strippers " or " clearers." The cylinder, licker-in, doffer, workers, and clearers, have their surfaces covered with " cards," the fineness of which is varied according to the class of work to be performed. Cards are composed of small bits of wire, inserted at an angle, into a foundation of leather, cloth, or a composite material which includes a layer of indiarubber. They are usually made in the form termed "filleting "a strip about 1J in. wide, which is carefully wound in a spiral manner upon the cylinders and rollers. Sometimes they are made in what are termed " sheets." Fig. 533 shows the first card with which the cotton comes into contact, that clothing the " licker-in " roller. The card for this roller is purposely composed of strong wire, of short cut. The COTTON MANUFACTURES. 745 kind now generally employed is flattened, and cut diagonally at the required angle. It is extremely strong, and by its action, without injury to itself, will destroy any foreign matter that may be likely to come from the lap, and which, if it passed this point, would subsequently injure the fine clothing of the cylinder and rollers. This specimen shows the fineness required for use in the longer staples of cotton. Fig. 534 exhibits the card used for clothing the main cylinder, when fine cottons are used ; its count or degree of fineness is 100's. No. 80's is used for low cottons, making coarse yarns ; 90's, for general purposes ; and 100's, for fine work. The clothing upon the doffer cylinder is nearly always 20 counts finer than that upon the main cylinder. The dirt-roller card, Fig. 585, is of a coarse wire openly set, so that it may readily receive into the interstices the motes, seed, leaf or other description of refuse, lying upon the surface of the main cylinder. Its cut is similar in depth to that of the licker-in roller. The carding rollers, or workers " and clearers," are both covered with cards ot the same fineness, or nearly so, as the main cylinder. The curved form of the illustra- tions shows the cards aa when actually ready for work. Good carding very greatly depends upon the careful adjustment of all the rollers to the surface of the cylinder, the cards of which, while set closely and evenly, should at no point touch each other. The rollers and clearers, in order to admit of this being done with the utmost nicety, are mounted upon two flexible " bends," very accurately turned, and fitted to the sides of the frame. The main cylinder, and all the rollers, are now usually composed of iron, which is less susceptible to the influence of damp or dry atmospheres than wood, the material formerly used. The bearings should be made of the most durable metal, and be kept carefully oiled. Every part should be set to work without oscillation, which, if permitted, soon renders good work impossible. The process is as follows : The machine having been supplied with the lap G, the end of which is passed under the feed-roller C, the lap-roller G' slowly revolves, unrolling the web from the lap. The " licker-in " B, running at a surface speed of about 800 ft. a minute, strikes the cotton in a downward direction from the feed-roller, combing the fibres straight, and carrying them to tl.e cylinder A, which, revolving at a surface rate of about 1600 ft. a minute, owing to its greater speed, and to the cards being bent in the direction of its motion upward, strips all the cotton from the former, at that portion of its periphery nearest the licker in. The cylinder carries the cotton forward to the first roller, which usually is a cleansing roller, and is technically called the " dirt- roller." Its surface speed is comparatively slow, only about 15 ft. a minute. Its function is to gather from the cotton all the remaining dirt, motes, seed, leaf, and neps, and to aid in combing the fibres straight The dirt extracted is carried round, and stripped from the roller by the attendant ; sometimes, however, a vibrating comb is attached for that purpose. The main cylinder carries the cotton onward to the rollers r and s, which successively assist in perfecting the cleansing and combing of the cotton. These rollers being set in opposition to the main cylinder, their contact surfaces move in the same direction, but at a greatly reduced speed. The cards arc set on the stripper with the teeth inclined in the direction of the motion, whilst those on the workers are disposed in the reverse way, the teeth being thus in opposition to those of the main cylinder. The latter carries the cotton past the stripper to the worker r, the teeth of which exert a combing action, owing to its relatively slow movement of about 20 ft. a minute. That portion of the cotton, which is taken up by the teeth of the worker r, is carried round, until, coming into contact with the stripper , it is taken by the latter, which moves at a surface velocity of 400 ft. a minute, and is itself stripped by the more swiftly revolving main cylinder. After passing the series of workers and strippers, the cotton is taken from the main cylinder by the doffing cylinder D, which has its teeth arranged in the opposite way, but moves only at the slow rate of about 60-70 ft. a minute in the 746 COTTON MANUFACTURES. same direction. The cotton is carried round its under side, until brought wiihin reach of the doffer-comb t, fitted upon vibrating arms, and stretching across the face of the doffer, from which it strips the cotton in a ti.in film. Its movement is vertical, or nearly so; it strips the doffer in its dtscent, and clears itself when ascending. It makes 600-1000 strokes a minute according to requirement, being driven by balanced cranks. From the dofter-comb, the cotton is delivered in a thin sheet or film, which is coudensed in its passage through a trumpet-shaped tube, and com- pression rollers r, whence it is carried over the pillar E, and, by an ingenious motion, is coiled in the can F, which stands upon a revolving plate. The cotton thus becomes a " sliver." This form of car ding-engine is probably most extensively in use, being best adapted for low and medium numbers of yarn. It is simple, easily set, and not liable to get out of order. The produc- tion exceeds that from flats, or the Wellman card, but the quality of the work is hardly equal. The canls should be put on both cylinders and rollers, closely, evenly, and with 'aiiform tension. After b< ing securely fastened, all should be evenly ground. The frame of the machine ought to be perfectly level, and placed on a floor free from vibration. The doffer, the taker-in, and the roll rs, should bo set exactly parallel with the cylinder, and be carefully adjusted as close as possible without touching. Another system of carding is the one in which the rollers and strippers of the machine descried above are dispensed with, the substitutes being a series of flats, extending from side to side of the machine, and covering the upper half of the cylinder. The under sides of these flats are covered with cards, and are so adjusted as to effect the same object as the above. This form of carding- engiue has passed through numerous mutations and improvements, before its present stage of perfection was attained. Formerly the flats were stripped by hand, which required steady atten- tion and skill on the part of the operative ; qualities which were not always found in combination. As the difficulty of obtaining a supply of efficient men increased, attempts were made, with varying degrees of success, to accomplish the work by mechanical appliances. Amongst the most successful of these, was the method devised by George Wellman, an American, who invented the machine so widely known as the " Wellman card." On its introduction into this country, it was taken in hand by Dobson and Barlow, machinists, further improved in numerous details, and adapted to work as either a first or " breaker," or as a finisher card. In the production of medium numbers of yarns, more carding is necessary than for lower counts. In many cases, the roller card is used as a " breaker " ; in others, various adaptations compounded of the roller and the flat card are used, and sometimes modifications of the latter alone. The finisher carding-engine on the Wellman principle, as made by Dobson and Barlow, ia represented in the accompanying illustration, Fig. 536. In its main parts, it differs little from the preceding. The series of flats / are fitted upon adjustable brackets g, which are so arranged as to admit of each flat being set accurately parallel to the face of the cylinder. The lever or arm h moves backwards and forwards over the semicircle of flats /; on this arm, is fitted the flat-lifting and stripping apparatus, which has proved to be such an ingenious substitute for human attention. By COTTON MANUFACTUKES. 747 means of this arrangement, the flats are lifted from their respective brackets, and turned upward, and their face is exposed to the action of the stripper roller, which clears away the accumulated waste that has gathered thereon. Immediately this has been done, the mechanism restores it to its place ; the arm resumes its movement, until it reaches the next flat that has to be stripped, when it again pauses, to allow the above performance to be repeated, and so continues until the whole of the flats are stripped, when the operations recommence. The order in which the flats are lifted varies, those nearest the lap needing to be stripped most often. The numbers of flats are so arranged that, whichever plan be adopted, each in proper order will come under the action of the stripper. The brackets e are for the reception of the grinding roller, for grinding the cylinder and dofler, without removing them from their positions. The revolving flat card is another form of the same machine. In this machine, Fig. 537, the flats are arranged in the form of an endless lattice ; the working flats rest upon a semicircular guide n, upon the tops of the sides of the frame, adjusted by means of the screws p. Those out of action are suspended upon carrier rollers g, over which they travel. The rate at which the lattice moves is very slow about 1 in. a minute. In their course, each flat is subjected to the action of the stripping roller k, after which it passes on to take its place amongst the working flats. Besides these principal forms of the carding-engine, there are several modifications, wherein the distinctive features of the roller and the Wellman card are combined. These are called ' combination " or " union " cards. The most remarkable machine employed in the preparation of cotton for spinning is the combing machine used for long-stapled cottons, for fine yarns. It was invented by M. Heilmann, of Mulhausen, and first became extensively known to the public through being shown at the Exhibition in London in 1851. The patent was purchased by a company of Manchester spinners of fine yarns, for the sum of 30,000?. They for a time restricted its use to them- selves, but subsequently permitted it to be supplied to the public, on payment of a royalty of 300/., which brought its cost to 500/. This was reduced, as the patent neared its expiration. It was, however, virtually extended by the patenting of improvements which experience had suggested. It has since been extensively adopted, and, for making the best classes of yarns, is now regarded as indispensable. Another combing machine, invented by Imbs, has since been favourably received. In the Heilmann "comber" (Fig. 538), the lap a is placed upon the rollers 6, whicb, by their revo- lution, unwind the fleece, and pass it down an inclined guide c to a pair of steel feed-rollers dd } ; the nether one is fluted, and the upper is covered with leather. These rollers have an intermittent motion, obtained through peculiar gearing, by which they are turned T^g r? f a revolution at a time. They deliver the cotton to a nipper, which opens to allow its passage. This nipper is com- posed of two parts the blade e and the cushion e 1 , the latter being covered with leather. The nipper-blade receives motion from a cam, at the gearing end of the machine. The motion is transmitted through two levers, a connecting-rod e 3 , and a shaft. The movement imparted to the blade is greater than is required to bring it into contact with the cushion plate, and the latter, being hung upon a pivot, and held forward by a spring, is pushed backward by the pres- 748 COTTON MANUFACTURES. sure of the blade, into a position which subjects the cotton to the action of the combing cylinder. A reverse movement then occurs, which permits the cushion plate and nipper-blade to advance with the cotton in their grip, to a point where, when the nipper-blade rises, the fibres are taken hold of by a detaching roller eam. Work then commences anew. The modern mule is one of the most perfect triumphs of mechanical skill. The processes described above are entirely automatic, the labour of the attendants being confined to superintend- ing : supplying the creel with rovings, piecing the broken threads, doffing the completed sets, and cleansing and lubricating the whole. In order, however, that the best results may be secured from the machine, it is necessary that an intelligent supervision should be exercised over it by managers, and great care be displayed by the attendants, otherwise serious damage can easily be done, and can only be repaired at great cost and trouble. Imperfect adjustment of the spindles and rollers, or neglect to lubricate the spindle footsteps, bolsters, and roller-bearings, or the friction surfaces of the headstock, may soon cause the neglected parts to wear down, and cause more or less defective action in the parts, greater labour for the attendants, and an inferior product for the result. One of the most important parts requiring attention is the setting of the drawing-rollers in all the machines where they occur. Should the top and bottom rollers of each pair not be set accurately parallel, a great deal of destructive action takes place. In one part, the fibre is overdrawn, strained, broken, or cut. On the opposite side, where the rollers are too close, it is underdrawn and nepped (rolled), the product from the different bosses varying also in counts. The fluted surfaces, and the leather covers, are also greatly injured, and soon wear out. Great skill and care have hitherto been required for setting the top drawing-rollers with the accuracy necessary to produce the best results, and these qualities are not always available. As tending to obviate these difficulties, we may draw attention to the recent invention of a roller adjusting gauge, by H. H. Clayton, of Hyde, whose name has already been mentioned in connection with an improved method of lap skewering. By the use of this gauge, rollers may be set with the greatest accuracy and speed by an unskilful person. The automatic or self-acting mule is not used for numbers of yarns much above 60's or 70's. When these points are passed, it has been found advantageous to retain the hand mule, which admits of being tempered to exigencies more readily than its rigid mechanical competitor. In spinning fine numbers of yarns, a distinctly different principle is introduced. When the carriage is within a few inches of the end of its traverse, the drawing-rollers stop delivering the roving, whilst the carriage, continuing its traverse, stretches the thread the remainder of the distance. This is for the same purpose as the " gain " of the carriage mentioned in spinning the ordinary counts. In spinning the finest counts, the ordinary hand mule itself has to give place to a still more sensitive form of the mule, called the " Box Organ." In this mule the arrangement of the parts is such as to compel the spinner to wait until all the vibration ceases, before making the different changes. This is requisite, as the least tremor has a tendency to break down the almost invisible threads. This machine is usually employed for numbers above 160's. The throstle-frame, as used in cotton-spinning to-day, is a development of the " water-frame " of COTTON MANUFACTUKES. 761 Arkwright. The latter machine, at the time of its invention, was justly regarded as displaying remarkable ingenuity and merit. In it, the system of drawing or attenuating the roving by means of rollers was first made a practical success, and proved so superior to all other modes that, until the invention of the mule, by Crompton, the water-frame stood far above all competitors. After the expiry of Arkwright's patent, the existence of which temporarily prevented the mule coming into use, the latter kept it in check, but never altogether displaced it. The relative superiority, in point of solidity and firmness, of yarn spun upon tlie water-frame rendered it extremely suitable for warp purposes, and better than could be obtained from the mule. It maintained this position until quite a recent date ; and even now, the best mule-spun yarn does no more than equal it. For producing some descriptions, it is yet esteemed superior to all other machines, and unless such exist in the ring- frame itself an important modification of the throstle it is held to be without a formidable rival. The throstle-frame is one of the series of bobbin-and-fly frames ; in fact, the parent of the whole. In appearance, it differs little from the roving frame, previously illustrated, except that in detail its parts are smaller, and its spindles are more numerous. The latter run at a velocity of 3000- 5000 rev. a minute, and are driven from a central shaft, placed within, and extending throughout the length of the machine, and supplied with driving pulleys at one end of the frame. This shaft carries a long tin cylinder, from which motion is transmitted to the spindles, by means of endless cotton bands, running upon small wharves on the latter. Each spindle is supplied with a flannel, leather, or cloth washer. On the top of each spindle, is mounted a flier ; and midway, is the bolster- rail. When ready for work, each spindle is supplied with a bobbiu a small short tube with a flange at each end. These flanges differ in shiipe, the top one being slightly convex on its upper surface, the bottom one being concave, causing the bobbin, as it were, to stand upon a ring, coinci- dent in its dimension with the circumference of the flange which constitutes the base. It is con- structed thus, in order to diminish the friction that would otherwise exist. The bobbin fits loosely upon the spindle, and rests upon the cloth washer. The spindle-bolster, in most frames, is made to traverse up and down a distance equal to the length of the tube of the bobbin, or the space between the heads. This is called its " lift." In some instances, there is an independent lifting rail. The " ends" or threads having been attached to the bobbins, and the machine having been started, the twist is put in the roving as it comes from the rollers by the revolution of the spindles, the thread passing through the top of the flier, and then around its leg to the bobbin. The latter, being only in slight contact with the spindle, has a constant tendency to fall behind it in speed, were it not pulled along by the attached thread. As, however, the latter is being delivered by the rollers, the bobbin is permitted to drop behind, so much as to take up the yarn as it is spun, winding it upon its barrel or tube. In order that the yarn shall be evenly distributed, the bolster or lifting rail carries the bobbin up and down the spindle, which causes the yarn to be wound in even layers. " Doffing," which is the operation of removing the full bobbins, and supplying the spindles with another set, is performed by the attendant called a "minder" always a female and an assistant child of either sex, denominated a doffer. In an ordinary sized frame, this generally takes 4-5 minutes ; and, as the bobbins are small, and doffing is a frequent operation, especially in spinning low Nos., it is obvious that a considerable amount of time is expended on that process, besides the cost of keeping a set of operatives to perform it. The latter amounts to id.-6d. a spindle per annum. In consequence of this, many attempts have been made to devise some method of superseding manual by mechanical doffing, one of which, invented by Bernhardt, a spinner of Eadcliffe, near Manchester, is generally regarded as a practical success, though the first cost of its application has prevented its extensive adoption. The throstle-frame has always possessed two great merits, those of being continuous in its operation, and of permitting the employment of female labour for its superintendence. These principles have led to numerous efforts to overcome its acknowledged defects, with the result that great improvements have been made from time to time. Amongst the earliest of these efforts must be ranked those of the late G. Bodmer, of Manchester. In patents taken out in 1838 and 1842, there are descriptions of a " bastard " spinning frame a throstle-frame without fliers, and with mule spindles, on which cops were spun like those in the mule. This frame possessed what would now be called the ring and traveller, and, without much doubt, it forms the basis of the modern ring-frame, the origin of which is generally attributed to American inventors. The throstle-frame, owing to its being available for the employment of female labour, was always the most popular spinning machine in the United States ; and the experience gained by its extensive use stimulated invention, and led to its comparatively perfect development. Whether the ring-frame was an English or American conception originally, it is undoubtedly the fact that it is in the latter country that it has been brought to such a degree of perfection as to render it a better machine than the throstle-frame, and also to endanger, for low and medium Nos., the supremacy hitherto enjoyed by the mule. In this country, during the last few years, it baa attracted a great deal of attention, and been extensively adopted. 762 COTTON MANUFACTUEES. The ring-frame is a modified throstle, and preserves its chief features. It differs from the latter machine mainly in having the flier replaced by a ring, which is fitted in the traverse rail. From this it takes its name. This ring is grooved inside and out, or made with flanges, and is furnished with a small piece of flat steel wire bent in a form almost like the letter D, with the vertical line cut through, to permit its passage over the flange of the ring, when it clips into the groove. This is called the traveller. Its office is to constitute a drag upon the yarn, by means of which the latter is wound upon the bobbin. Its size and weight depend upon the counts of yarn required to be spun : coarse yarns demand the largest rings and heaviest travellers ; and the finer yarns, the opposite. The capability of the frame extends from the lowest numbers to 50's or 60's ; but it has not been found expedient as a rule to pass the first-named point. Owing to the high speed of the spindle 5000-9000 rev. a minute that has been attained in the ring-frame, it has been found that the dimensions and construction of the spindle are points of vital importance. The frame alluded to above is furnished with what is known as the Rabbeth spindle. Of the three illustrations contained in Fig. 549, A represents a section of the spindle complete with bobbin ; B, the spindle with its sleeve ; 0, spindle complete with bobbin. A brief description will suffice to render its construe- 649 tion easily comprehensible. The steel spindle A is furnished witk a cast-iron sleeve B, which is firmly secured to it. This sleeve at its lower extremity has the wharve C cast upon it, for the reception of the driving band. A tubular bolster D is constructed to receive the lower part of the spindle. Literally it is a com- pound of bolster and footstep. The top of its tube is furnished with a German silver bush E, of which the dark lines indicate the section. This, when the spindle has been inserted, forms a cavity below, constituting an oil chamber or reservoir H. This effectually secures the per- fect lubrication of the spindle foot, and of its frietional portion in the bush E at the top of the bolster D. The chamber carries sufficient oil to ensure perfect lubrication for several months, and experience demonstrates it to be efficient. The question arises at this point as to whether its lubricating properties may not become impaired or destroyed after being sub- mitted for a lengthened period to the attrition of the revolving spindle; or whether some chemical action may not be induced which will essentially change its nature. In con- tact with brass in the bolster or footstep, after some time, oil becomes turbid, green, and slightly viscid. If this point has been decided favourably, as we are assured, this arrange- ment would appear to be unobjectionable. Should the oil work up and over the top of the bolster, the bobbin and yarn are still quite free from risk of contact, the oil falling down in- side the sleeve B, and passing out beneath the wharve upon the exterior surface of the bolster. ABC By means of the sleeve B and the bush E, the oil is securely protected from contamination by loose fibres, dust, or atmospheric influences. Upon the top of the wharve C, a brass cup F ia securely fixed, for the reception of the foot of the bobbin G, which, however, has its chief bearing at the bushed part near the top of the spindle. The brass cup assists to steady the bobbin, and preserve the balance of the spindle ; but its principal function is to facilitate doffing. In removing the full bobbin, the thread between the bobbin and the traveller coils itself in an open spiral upon the sleeve of the spindle. The empty bobbin, being placed upon the spindle, pushes the thread downwards into the cup, where it is firmly held by the contact of the two surfaces. After each operation of doffing, the threads are thus secured without loss of time, simply by the process of supplying the frame with a fresh set of bobbins. The bottom of the bobbin being within the cup, and the thread from the traveller passing over its edge, it is just in the proper position for recommencing spinning. The bolster is st cured in position by mi ana of the nut K. The wire J ia COTTON MANUFACTURES. 763 for the purpose of retaining the spindle in the bolster during the doffing operation, or when taking the bobbin off for other reasons. Another of the most successful ring-frame spindles is represented in Fig. 550. It is known in this country as the Booth-Sawyer spindle. Like the Eabbeth, it is of American origin. In the illustration, 1 represents the outline of the spindle mounted with bobbin; 2 is a vertical section of the same ; 3, the bare spindle. As will be seen from the third sketch, the spindle is very simple, carrying only the wharve E, and a cup forming an oil chamber K. The bolster has a tube B, which is spirally grooved inside. Its basement is constructed in the form of a tube L, which receives the oil-cup K on the spindle. The bush 4, composed of bronze, is fitted into the top of the bolster-tube, and constitutes the bear- ing. The footstep C is furnished with an oil chamber F, and a tube extends to the wharve. In the bolster, lubri- cation is effected at M, when the oil poured into the cup flows through the hole into the bolster-tube, until it meets the revolving spindle, which carries it along the spiral groove to the bronze bush, where it comes into contact with the bearing surfaces between which it is forced by the pressure of the stream ascending from below. As this is con- stantly going on, the oil would be liable to pass over the top, flow away, and be wasted ; but against this, provision is made by vertical grooves being cut into the sides of the bush, as seen at 4, and in the section of this at 5, the bush being inserted a little below the top of the bolster-tube, the oil which overflows passes down the vertical groove P in the bush, and at O re-enters the bolster- tube, there to be used over again. This is continuous, so that the spindle is kept perfectly lubricated, and no oil is wasted. When the spindle is at rest, the oil flows down the spiral groove into the spindle cup K, where it remains until work is resumed. Both oil chambers are supplied with covers, to prevent the entrance of loose fibre, dust, &c. Experience has proved this to be an efficient and economic; 1 method of lubricating the spindle, which, owing to the high speeds attained, is an absolute neces- sity if the machine is to be preserved for any length of time in working order. The bobbin for the Booth-Sawyer spindle is designed to secure lightness, firmness, and steadiness on the spindle. It possesses a wide bore, which extends almost to the top, where it is reduced so as to fit the spindle point only. In the centre of its length, it is bushed, at which point the second bearing is formed. Thus being firmly held at two points upon the taper spindle, it is quite free from vibration. There is a tendency in the "traveller" to collect fibre upon itself, which seriously injures the quality of the yarn, by increasing the strain upon it beyond the point it is calculated to bear. Many ingenious attempts have been made to overcome this difficulty, and several plans now in use are more or less efficient. The ring-frame appears to have a great future before it ; and since its introduction a few yt ars ago, it has greatly risen in public estimation. At the moment of writing, we are informed that the largest firm of cotton machinists in this country have not a single order in hand for the ordinary throstle-frame, whilst they have several for the ring-frame. Every maker of cotton machinery in England has turned his attention to it ; and many have sought to improve upon its present condition. As ordinarily used in America, and as introduced into this country, there are several drawbacks against its general adoption. The necessity of employing a bobbin, upon whic to wind the yarn, would seriously interfere with the trade in yarn as at present conducted. The small quantity of yarn that can be put upon the bobbin, the weight of the latter in proportion to 764 COTTON MANUFACTUKES. the yarn, and the cost of its transit to and fro between the spinning mill and the weaving shed, would form important items of expense, and do much to neutralize all its advantages. A very great proportion of the yarn spun in this country is produced for sale in that form, and is manufactured elsewhere. This is not the case in America; hence the same difficulty has not been experienced there. Another obstacle to its adoption is the fact that it has not yet been adapted to produce weft yarns, or filling, in the best forms. For some time, filling has been spun upon the ring-frame in America ; but where this is the case, bobbins have been employed, and these have not been capable of reduction below a point which required the use of a large shuttle in the loom, or the re-winding of the yarn upon pirns, both of which courses are extremely objectionable. The ingenuity of English machinists has therefore been directed towards the removal of these difficulties, and to the modification of the frame so as to fit it for incorporation with the existing system. The attempts made have been partially successful. Several makers have been able to dispense with the bobbin, and have spun cops upon paper or metallic tubes. This may be regarded as a partial success, but it will hardly be perfect until these can be abolished altogether. " Pin " cops, otherwise " pirn " cops, for the shuttle have also been successfully produced from machines constructed by Samuel Brooks, of Manchester, and John Tatham, of Rochdale. The macl lines upon which this has been done only require perfecting in a few points of detail before they become commercial successes ; and this may be confidently expected in a very short time. The adoption of the ring-frame is greatly to be desired, from the fact that it will preserve a large amount of capital invested in mills erected 25-40 years ago, but which, owing to recent improvements in the construction of the mule, are unable to compete with mills furnished with the most modern plant. These, however, could be easily adapted to the ring-frame : in fact, without alteration even are nearly as suitable as new erections would be. On this ground, it is to be hoped that success may attend the efforts being made to improve it. Reeling. This is one of several subsidiary processes carried on in connection with spinning, according to the character of the business transacted. It is used in the preparation of yams for export, and also when the yarn as such has to undergo the further processes of bleaching, printing, or dyeing. For the former purpose, it is " straight" reeled, and made up into " short" bundles ; for the latter, " cross " reeling is preferred, and the yarn is made up into '* long " bundles. Where throstles or ring spinning frames are used, reeling, or " ball-warping," is a necessity, when the yarn is sold from the mill, as the transit of the bobbins backwards and forwards entails expense and loss, which it is usually sought to avoid. Warping will be explained under the next division. Doubling. This is a process in the course of manufacture, and is generally carried on in con- nection with spinning, though it often forms a separate and independent business. In it, two threads are twined together to form one. The throstle machine is most usually employed for the purpose. It is in all respects the same as the spinning-frame, except in being deprived of the drawing-rollers, which are replaced by a single pair of rollers of larger diameter. There are two processes of doubling, culled "wet," and "dry." In the former, this pair of rollers are covered with brass, to prevent oxidation. After it leaves the cop or bobbin, the yarn is passed through zinc troughs filled with water. Inconvenience arises from the use of these troughs, through their liability to become receptacles for loose fibre, dust, &c which is agitated when the water is renewed, and fouls the yarn, or necessitates the stoppage of the frame during its subsidence. This may be avoided, and all the troughs in a frame may be fed at one operation from a supply pipe at the end, by connecting the troughs together by means of little inverted U-shaped syphon pipes. This will prevent damage to the yarn, and loss of time. After passing the troughs, the yarn goes between the pair of rollers to the flier on the spindle, which gives it the requisite twist, and delivers it to the bobbin ; this, lagging slightly behind the spindle in its revolution, winds up the thread. In the doubling-throstle, especially where fine numbers are doubled, several serious disad- vantages are encountered. One of these is in the fact that after doffing it is necessary to oil the spindles, in order to make the bobbin slip more freely than it otherwise would, so as not to break the fine threads in process. The consequence is that many bobbins soon become saturated with oil, the dry porous wood readily absorbing it, whereby the weight of the bobbin is greatly increased, and the drag is rendered unequal as compared with others that have not absorbed oil. This produces irregularity in the yarn. A greater evil is the large number of bobbins that are rendered useless. The saturated bobbins also stain the yam wound upon them, by which its value is depreciated 3d.-Qd. a Ib. Often when a frame has been replenished with bobbins it is found that several will not slip ; and the threads, after breaking and being pieced several times, are thereby rendered unfit for their purpose. They are then taken and stripped with a knife: yarn worth l-5s. a Ib. being thus reduced to waste, worth only 4-6<2. a Ib. In numerous other ways, yarn is stained by the saturated bobbins, and thereby greatly depreciated in value. A great quantity of oil is also consumed in the lubrication of the spindles, and a heavy loss is sustained weekly by the necessity of throwing out as unfit for use a great number of saturated bobbins. The losses thus arising have led to many attempts to devise a remedy, though, until quite COTTON MANUFACTURES. 765 recently, -without much success. An invention just perfected and patented by Taylor and Eamsden, of Bolton, has, however, accomplished the end sought. The arrangement is illustrated in Fig. 551. The spindle is reduced in length, and slightly tapered towards the top. The flier / is removed from the summit of the spindle the position it occupies in the ordinary throstle inverted, and relegated to the place formerly occupied by the bobbin b. In- stead of being made fast, as before, it has a boss b" fixed to it, and is left loose upon the spindle, resting upon the bolster-rail r, with only the ordinary leather washer intervening. Midway on the spindles, is placed a braid b', uniform in height. These braids have a rib cast upon and across their upper surface. The bobbin 6 being put upon the spindle, descends to the braid, the rib upon the latter fitting into a groove in its base. It is there held with sufficient firmness to pre- vent slipping. It will thus be seen that with the inversion of their relative positions, their functions are also exchanged : the drag being obtained from the flier, instead of the bobbin, as before. Fig. 551 exhibits the application of Taylor and Eamsden's invention to existing spindles. In the construction of new machines, it would be further modified, as seen in Fig. 552. This repre- sents the most perfect form it has yet attained. The important changes effected will be best seen by contrasting the following particulars of the old and new forms : length, 16 in. : 11 in. ; weight, 14J oz. : 5 oz. ; length of traverse, 2 in. : 1J in.; weight of flier, 3 oz. : 1 oz. ; diameter of bobbin across top, 1J in. : 2 in. The new form easily attains a speed of 7000 rev. a minute, whilst maintaining good results. The braid 6' is dispensed with. The advantages of this arrangement are obvious, and will commend them- selves to everyone practically acquainted with the matter. The bobbin is placed quite away from contact with oil, and revolves with the spindle. There are consequently no bobbins saturated, and no oil-stained yarn. The fliers not being to take off, doffing can be performed by the minder, a spindle at a time, without stopping the frame. This increases production and diminishes expense, dis- pensing with doffers' wages. The space between the arms of the flier is also increased. Bobbins can be used until they break, and the introduction of larger flanges greatly increases their capacity, and reduces the number of knots made by piecing the yarn in the winding room. There is no waste from snarled yarn at the spindle top, as in the old arrangement. In wet doubling, the fliers soon become rusty, and comparatively rough, which, owing to the thread having to pass several times round the arm, causes it to be frayed and roughened. In the new arrangement, this is obviated, the surface of the yarn is more glossy and free from fibre, enabling a better thread to be made from a standard quality of cotton, or the standard to be lowered, whilst the quality is maintained. In a large establishment, say of 65,000-70,000 spindles, the economy resulting 552. from this invention has been estimated at 15001. per annum, and may safely be put at a considerably higher figure. The ring-frame has also been very successfully adapted to doubling, and the yam from it occupies a position intermediate in its characteristics between the productions of the throstle-frame and the twiner. The last-named machine, the twiner, is an adaptation of the mule for doubling purposes, and the characteristics of the yarn from it are that it is less firm and hard than that from either of the above-mentioned machines. Casing. This is a process in which yarn is passed through a jet flame, in order to burn from the surface of the yarn the ends of the fibres that have not been thoroughly incorporated in the thread in the course of spinning. The yarn subjected to this process is usually doubled, and is used in the lace trade, and when polished for mixing with silk goods; in this connection, it usually forms the back of what are termed silk-faced textures. The gasing machine is like almost all others, nearly automatic. The yarn is wound from one bobbin to another, and, in its passage, goes through the flame. When the thread breaks, or the supply is finished, the gas jet automatically drops out of its position, until the connection is again made. In stopping the machine, the same thing occurs. Every care is taken to reduce breakages of the yarn to a minimum, as knots are a serious drawback to the value of this description of yarn. An essential quality of a good machine is that the pace of the thread should be capable of the nicest adjustment, so that it may never be under-singed nor burnt The driving in order to secure this object should also be thoroughly uniform. There are several machines in the market, differing somewhat in details, but they call for no further description. Polisl ling. This is another of the subordinate processes employed in special branches of the 766 COTTON MANUFACTURES. cotton industry. In this, the hank of yarn is placed over two rollers of a machine, the distance between which is gradually increased, thus stretching the yarn to its full extent, whilst a sizing of beeswax and other materials is applied thereto. This imparts to the thread a beautiful gloss, and when the yarn is dyed in bright colours, the effect is exceedingly rich. Polished yarn is mostly used for silk mixtures. Cotton Weaving or Manufacturing. As technically understood, manufacturing forms the second great division of the processes usually grouped under that term, when used in its most extended signification. In the restricted sense in which it has to be considered, it includes all the processes necessary to transform ynrns, after they leave the spinner, into the various descriptions of cotton cloihs. These processes are five in number, and may be briefly defined as follows : 1. "Winding." This is the operation of transferring yarn from the cop or hauk, to bobbins, to prepare it for the next stage. 2. " Warping." In this stage, a given number of bobbins, generally 300-600, are placed in a creel, and the threads are wound thence in parallel order upon a large beam, to a length of 3000-5000 yds. This is the plan pursued where the sizing machine is used. Where the old system of ball sizing is retained, the method is different. 3. " Sizing." This consists in immersing the yarn in a fluid composition, containing water, flour, starch, and other materials ; the object is to solidify and strengthen the threads, to enable them to withstand the friction and strain inaident to the subsequent process of weaving. There are three methods of doing this, which will be described in their place. 4. " Drawing- or twisting-in the warp." This is simply furnishing the warp with the necessary healds, or harness, to make it ready for the loom. 5. " Weaving." This is the art of interlacing threads, in snch a manner as to make a web or texture. It is subdivided into branches ; plain, twill, figure, and leno weaving. All these arise from the order in which the threads of the warp are opened to receive the weft, or filling, which composes the cross threads of the texture. In primitive times, the art of weaving was of the simplest character. The weaver spun a single thread, and wound it into a ball ; then stuck two or three sticks into the ground, and passed the thread around them a sufficient number of times to give the breadth and length required for the warp ; next he interlaced a second thread by the simple process of darning, pressing the latter as closely together as he desired by the aid of his fingers. For a long time, very little progress appears to have been made. Some of the ancient nations, such as Egypt, Persia, Assyria, and Greece, attained great skill in the textile art, though the instruments they possessed showed little advance upon the above. India for many centuries possessed an almost world-wide reputation for the variety, beauty, and fineness of its textures ; all these were manufactured by the simplest tools, the thread being spun by the distaff and spindle, or the single thread wheel, and the shuttle being passed through the open warp from hand to hand. It is, however, to Lancashire that the world owes the impetus given to invention in the textile arts. Nearly all the great improvements have originated and been perfected within the boundaries of tlie county, and within a few miles of each other. The first great step was made by the elder Kay, of Bury, by the invention of the picking-stick, and the attachment of boxes to each end of the slay or lathe of the loom, for the reception of the shuttle, in place of the hand of the operative. This so greatly increased the productive power of the weaver, that cotton weft yarns the warps were of linen became exceedingly scarce, and advanced so much in price, that the spinners enjoyed a period of great prosperity. The weavers were often compelled to wander from cottage to cottage for several days in order to collect a sufficiency of weft to supply them for the remainder of the week. This state of matters stimulated invention very greatly, and, in many secluded corners, " conjurers," as the people then called inventors, were working to devise remedies for the scarcity of yam which so many felt. Jas. Hargreaves, of Oswaldtwistle, near Blackburn, was the first to accomplish on his "jenny," the feat of spinning more than one thread at a time. The treatment he met with need be only cursorily alluded to here. The rapid manner in which the new invention spread in East Lancashire was not regarded with complacency. Mobs broke the jennies wherever they could find them, and compelled Hargreaves to fly for safety, which he found in Nottingham. Arkwright, thus warned, when lie bad made his water-frame a practical success, migrated in the same direction. Oompton closely followed these men with his combination of the jenny and the water-frame, which received the name of the " mule." The details of the two inventions last- nanud were wrought out almost upon the same spot, Bolton, and not long apart. The invention of the jenny, the water-frame, and the mule, soon yielded an abundance of yarns, and the question arose as to how to work them up. Mechanical production suggested a mechanical power of consumption : hence the power-loom. A clergyman named Cartwright appears to have been the first to broach this idea, and to attempt its realization. After spending several years, and a considerable fortune, in the attempt, he only succeeded in achieving a very limited COTTON MANUFACTURES. 767 degree of success. But the idea was not destined to be lost : others were assiduously labouring to attain the same end. Horrocks, of Stockport, and Miller, of Glasgow, soon succeeded better; Bulloughs, of Blackburn, and a host of minor inventors, have contributed to bring the loom to its present degree of perfection. To no one, however, can be given exclusive merit ; each man's im- provement forms a complement to preceding invention?, and the earliest require the latest to perfect them. The system as now existing has been developed from the experience and labours of many. It is not yet perfect ; frequent contributions are being made, and more are needed. The Weaving-Shed. The remarks made concerning the selection of a site for a spinning-mill, apply with equal force to that for a manufacturing establishment. To secure freedom from vibra- tion, and a cool and soft atmosphere, the weaving-shed is always by preference placed on a ground floor. The preparation may be conducted in a building of two or three stories, should it be desirable to economize the ground space. The site should always be chosen so as to permit the windows of the roof of the weaving-shed to run in a direction from oast to west, in order to present the glazed portion to the north, the light from this point being the greatest, most steady, and best adapted for manufacturing purposes This point secured, regard must be had to the arrangement of the looms, which ought to run at right angles to the bays of the roof, in order that the slay, or lathe, may not cast shadows upon the warp in the process of weaving, and thereby interfere with the ability of the weaver to perceive the occurrence of breakages, or flaws of other descriptions. Figs. 553 and 554 show plan and section of a well-arranged weaving-mill, from designs by the architects who furnished those for the spinning-mill. It will be seen that the general arrangement is such as to avoid the necessity of the material going over the same ground twice, which would increase the cost of handling. Assuming that the supply of yarn is purchased, it is brought into the establishment in large skips or baskets, holding 300-400 lb., and is warehoused in the yarn store. 768 COTTON MANUFACTURES. From here, it is delivered to the winders ; next, upon bobbins, to the warpers, and thence upon beams to the sizers. After undergoing the sizing process, it is delivered upon loom beams, to the " drawing-in-" or " looming-room " for the drawers or twisters to finish it for the loom. Hence, furnished with healds, it passes to the weaving-shed, in which, so far as the manufacture is con- cerned, it is completed. It is only in very rare instances in this country that bleaching, dyeing, or printing is carried on in the same establishment. Weft yarns, not requiring any treatment in passing from the spinner to the weaver, when received, are warehoused in the weft store, whence they are delivered in small cans or baskets over the counter to the weavers in the loom shed. When the cloth is woven, it is cut into certain lengths, called " pieces," and sometimes collected from the weavers by a labourer, carried into the warehouse, and entered to each weaver's credit. In other cases, the weavers perform this duty themselves. The cloth ia next examined, made into bundles, and despatched to the agent or merchant in Manchester. The above plan is designed to represent a mill of about 700 looms, and the complementary machinery, working medium numbers of yarns. It contains fonr winding frames, of 300 spindles each ; six warping frames; two sizing machines, and 700-750 looms. The motive power is supplied by two tubular boilers, 30 ft. in length by 7 ft. diameter, which are supplied with a Green's Econo- mizer of 160 pipes ; and two horizontal engines, driving a large fly-wheel, grooved for the reception of ropes, by which power is transmitted to the main driving-shaft, which is walled off from the shed, in order to secure cleanliness, and to partially deaden the noise produced by the gearing. From the main shaft, and connected with it by bevelled gearing, a line of light shafting runs parallel with and between each two rows of looms, set back to back, which are driven from it. In the changes inevitable in the conduct of a large business, such as is implied by a mill like the one described, it sometimes occurs that orders for lightly picked goods will be received, in working which, the looms will over- run the preparatory department, which would cause inconvenience, loss of time, and diminished production. In order to avoid this result, a small engine is provided for overtime working of the preparatory department especially the sizing machines, without running the shafting and gearing of the other portion. The steam left in the boilers and which would otherwise condense during the night is generally sufficient for this purpose, and is thus utilized. A mechanics' shop for making repairs completes the equipment of the establishment. Winding. The first machine in the complement is the winding frame, of which a view is given in Fig. 555. It is one of the simplest machines in the series necessary for manufacturing ; and its parts require only brief description. A skewer rail a extends throughout the length of the frame; 6 is the knee-board, covered with flannel, to cleanse the yarn from leaves, motes, and impurities. The next part is the traverse-rail, carrying the brushes c, the dark line running below representing a steel or glass rod. The box d is provided for the operative to pile the yarn upon, in a position convenient to the hand. The spindle e, carrying the bobbin /, is connected between the wharve T FOR REFERENCE 1 NOT TO BE TAKEN FROM THE ROOM UC SOUTHERN REGIONAL LIBRARY 000784494 7