1 THE LIBRARY OF THE UNIVERSITY OF CALIFORNIA PRESENTED BY PROF. CHARLES A. KOFOID AND MRS. PRUDENCE W. KOFOID 'k THE MILROY LECTURES 1899 By the same Author, SECOND EDITION. With 13 Illustrations. Crown 8vo. 6s. %d. ESSAYS ON RURAL HYGIENE. Lancet.— 'Well wortliy of the serious coasideration of those into whose hands is committed the control of the public health.' British Medical Journal.— ' Well worth reading. Dr. Poore attacks the local authority with much spirit, and with unanswerable logic on some points.' Glasgow Herald.—' A highly important book. The whole book is an education in itself. It is a volume to be read and re-read equally by house- holders and by professional sanitarians. Our only regret is that amid the flood of hygienic literature which is, year by year, turned loose upon the world, there are so few books of this type— fearless, honest, and scientific criticisms of existing errors, and full, likewise, of recommendations whereby these errors may be rectified.' SECOND THOUSAND. With 36 Illustrations. Crown 8vo. 3s. Qd. THE dwelling-house. Times.—* Dr. Poore does good service in hammering away at the folly of taking town sanitation as a model for more happily situated communities- . . . When it comes to applying model by-laws, intended for large towns, to niral districts, and when rich men build country houses on the base model of the London " mansion," then he is justified in protesting. As a counter- blast to the worship of such false gods his book is useful and welcome.' Engineer. — • Lack of space prevents our quoting freely from the section headed " Eemedies for Overcrowding," which is admirable, and should be read and re-read by sanitary authorities until they have thoroughly digested it.' LONGMANS, GREEN, & CO., 89 Paternoster Row, London, New York and Bombay. THE EAETH IN RELATION TO THE PRESERVATION AND DESTRUCTION OF CONTAGIA BEING THE MILROY LECTURES DELIVERED AT THE ROYAL COLLEGE OF PHYSICIANS IN 1899 TOGETHER WITH OTHEB PAPERS ON SANITATION BY GEORGE VIVIAN POORE, M.D.(Lond.), F.R.C.P. PBOFESSOB OF THE PBINCIPLES AND PBACTICE OF MEDICINE UNrV'EBSITY COLLEGE, LONDON PHYSICIAN TO UNIVEBSITY COLLEGE HOSPITAL BTC. LONGMANS, GREEN, AND CO 89 PATERNOSTER ROW, LONDON NEW YORK AND BOMBAY 1902 All rights reaerred k^» Digitized by the Internet Archive in 2007 with funding from IVIicrosoft Corporation http://www.archive.org/details/earthinrelationtOOpoorrich TO SIR WILLIAM SELBY CHUKCH, Bart. PBESIDENT OF THE ROYAL COLLEGE OF PHYSICIANS THIS BOOK IS DEDICATED WITH GREAT RESPECT BY THE JUNIOR CENSOR (1902) i^S565Sl PEEFAOE The Author feels that no excuse is needed for the republication of the lectures and papers included in this volume, which deal with subjects of national importance. To Mr. George Fernet, M.E.C.S., &c., his warmest thanks are due for much invaluable help in passing the volume through the press. May 1902. CONTENTS MILKOY LECTUEES CHAPTER PAGE I. Earth — Pathogenic Saprophytes — Tetanus . . 1 II. Anthrax 9 III. Diarrhoea — Dysentery — Cholera . . . .22 IV. Malta Fever — Plague — Diphtheria . . . . 29 V. Malaria — Blackwatbr Fever — Tsetse Fly Disease — LoupiNG III— Texas Fever— Horse-sickness 38 VI. Enteric Fever 46 VII. The Maidstone Epidemic 58 VIII. Immunity — Danger of Wounds 69 IX. Practical Considerations 78 X. Agriculture 87 XI. The Maintenance of the Fertility of the Soil . 96 XII. Sanitation in Holland 104 XIII. Carrington Moss 116 XIV. Conclusions 125 ADDKESS TO THE ROYAL MEDICAL AND CHIRURGICAL SOCIETY XV. Enteric Fever caused by Pollution of Public Water-supplies 135 XVI. Recommendations as to Water-supply — What TO DO WITH Infected Material, &c. . . 151 CONTENTS CHAPTER PAQB XVII. Application of Excreta to well-tilled Humus 165 XVIII. Enteric and Overcrowding . . . . . 177 VARIOUS PAPERS XIX. The Sanitation of Camps — Flies and the Science OF Scavenging 189 XX. An Experiment in Sanitation— Collection of Rain-water — Disposal of Slop- water . . . 201 XXI. Milk in its Relation to Health and Disease . 216 XXII. Some Dietetic Problems 281 Index . . 251 ILLUSTRATIONS FIGURE PAGE 1,2. TUTSHAM-IN-FlELD 61 8. Tutsham-in-Orchard 62 4. EwBLL 62 5. 'Spot' Plan of Surroundings of Maidstone Bar- racks AND Prison 68 6. View of Cottage To face 203 7. Plan of Cottage 203 8. Slop Gutter : Longitudinal Section .... 209 9. Duplicated Tank-filter 210 10. Filtration Gutter 211 11. Slop Gutter : Cross-section 211 12. Earth Closet: Ground Plan 214 13. Earth Closet: Vertical Section 214 THE EAETH IN EELATION TO THE PRESERVATION AND DESTRUCTION OF CONTAGIA* CHAPTER I EARTH— PATHOGENIC SAPROPHYTES-TETANUS That which we commonly speak of as earth, soil, or humus, is largely composed of excreta and the dead remains of animals and vegetables, which, as the result of fresh biological processes, are either returned to the bodies of living vegetable organisms, or, after becoming mineralised and soluble, are washed down- wards by the rain and ultimately find an exit in the sea. It is obvious that not only does ' earth ' vary in composition with the varying conditions of subsoil, climate, flora and fauna, but that * earth ' must undergo seasonal variations necessitated by the vigorous upgrowth in the spring or the decay of the fall — the heat and drought of summer or the flood and frost of winter. The interstices between the particles of * Being the Milroy Lectures delivered before the Boyal College of Physicians, London, in 1899 (Chapters I. to XIV. inclusive). B 2 EARTH * earth ' are filled at one time with air, at another time witli water, and the line of demarcation between earth and air on the one hand and earth and water on the other is often not very definite. Again, the dust which is suspended in the air and which settles on everything is liable to contain infective particles, harmless to breathe but dangerous if they fall upon a wound. It is obvious that such particles may be regarded as belonging to the earth or the air. Some of them doubtless emanate from the earth, having been raised as dust ; but we must admit that there may be organisms which grow in the air, live in the air, and die in the air without ever touching earth or water and which elude all attempts at identification or artificial cultivation. While there are organisms which may live indifferently in air or watqr, others are probably more exclusive in their obligatory conditions. The mutual interaction of earth, air, and water must never be lost sight of. It is the life in the earth, both vegetable and animal, which helps by its influence on vegetation to maintain the quality of the atmosphere. Again, it is the earth which gives the quality to spring and river water. Pure water is a body of definite chemical com- position, and pure air is a tolerably definite mixture of gases, and it is not difficult approximately to measure the degree of pollution of either. The chemical comr position of earth, on the other hand, is complex and constantly changing, and it is not possible for the chemist to fix any standard of quality. The practical agriculturist by the aid of touch, smell, and vision will say at once whether any given sample of earth is foul or pure, sour or sweet, rich or poor, fertile or sterile, and we must perforce content ourselves with the terms used by the practical man. The word * earth ' in the PATHOGENIC ORGANISMS 3 ensuing lectures will usually be regarded as meaning humus in a healthy condition. There are certain pathogenic organisms which are constantly found in the earth and which appear to be ubiquitous. They adhere to our skin and clothing, get under the nails, and lodge in the hair. They produce various diseases of wounds and wounded persons, and we now recognise that in the absence of those precautions which we call * antiseptic ' it is never safe to inflict even the smallest wound. The modern surgeon not only renders his hands and instruments aseptic, but he operates in spotless garments and endeavours to have an operating-room as clean and free from dust as possible. The organisms which produce the various wound infections are saprophytes which flourish exter- nally to the body. They are ubiquitous and (probably) necessary, and so long as we have a whole skin and uninjured mucous membrane they do us no harm. As all organic matter is constantly circulating, passing through death to other forms of life and necessarily undergoing humification as it does so, it follows that the agents of these changes, the microbes which are to this end propagated in the soil, vary with the circumstances. Houston ^ gives the estimated number of microbes per gramme found in twenty-one samples of soil. These vary from 8,326 in a virgin sand and 475,282 in a virgin peat to 115,014,492 in the soil from the trench of a sewage farm. Broadly speaking, the microbes bear a proportion to the amount of dung. Warington estimated that a gramme of dung from a cow fed on hay contained 165,000,000. They all, presumably, have their optimum conditions — chemical and physical quali- ties of the nutritive medium, access of air or other gases, ' Local Oovemment Board Eeport, 1897-98. b2 4 EARTH lightness or darkness and temperature — and when the optimum conditions concur, growth and multiplication go forward at a pace which we can hardly appreciate. The fact that for the growth of some the access of air is necessary, while others obtain their oxygen from the medium in which they grow, and others, again, are able to take in oxygen from either source, has formed the basis of a classification which has assisted our under- standing. Saprophytes, including those which produce wound infection, are presumably of service in bringing about the decomposition of complex organic bodies. Whether we are able to check the growth and multiplica- tion of these facultative parasites outside the body is doubtful, and whether or no we should be gainers or losers by so doing is still more doubtful. Bacterio- logists have experienced no little difficulty in discovering the exact conditions which are necessary for the growth and development of many of the micro-organisms which have been studied. Some are more exacting than others, and those which are best able to accommodate them- selves to varying circumstances naturally obtain the mastery when several are attempting to grow simul- taneously in the same medium. Some of the larger saprophytes, such, for instance, as the common mush- room, require no little skill for their artificial production. Their cultivation requires far more attention to exact details than is necessary with ordinary green-leaved garden plants. We know that for a few weeks in the autumn they may appear in great numbers in dry pastures where horses have been fed, provided the conditions of the air as to temperature, light, and moisture be favour- able, and we also know that directly the necessary conditions fail the mushroom harvest is at an end. We also know how strange is the predilection of certain TETANUS 5 fungi for the dung of particular animals, and I would allude to a list furnished to me by Mr. George Murray, F.K.S., which shows that the optimum conditions for the growth and development of these short-lived and delicate organisms must be marvellously subtle and pro- bably quite beyond the ken of the chemist. Tetanus I will now proceed to deal seriatim with some of the contagia which are best understood, and will begin with tetanus. Among the ubiquitous organisms which are habitually found in earth is the bacillus of tetanus. It is said to be present in almost all rich garden soils and that the presence of horse-dung favours its occurrence. It is strictly anaerobic and has been artificially cultivated by Kitasato in an atmosphere of hydrogen. It forms spores and grows best at a blood heat. Marchesi has found it at a depth of two metres but no lower. The pure cultivation of the bacillus, which has a disagreeable aromatic odour, is often not very virulent. It is fatal to animals as well as man, and among animals the horse appears to be most liable to be attacked. Infection always takes place by inoculation through the wounded skin or mucous membrane — never, it is believed, through the healthy alimentary or respiratory tracts. Cases of * idiopathic ' tetanus are reported, but it has fallen to the lot of few of us to see a case, and professional opinion seems to lean to the idea that in such cases the inoculat- ing wound has been overlooked. The toxin which the bacillus brews locally in the wound is toxic to the central nervous system, and the antitoxin to be effectual must, it is said, be injected subdurally into the central nervous system. The exhaustion of the nervous system seems to increase its vulnerability, which is, perhaps, the reason 6 EARTH why tetanus has been relatively common in the domain of military surgery. There seems to be no doubt as to the ubiquity of the tetanus germ. Every child who falls on the ground and gets an abrasion of the skin, all tillers of the soil who get accidental wounds in the course of duty, and every horse which * breaks its knees ' by falling in the London streets, runs, potentially, a risk of inoculation with tetanus. In the face of the ubiquity of the cause the rarity of the disease is remarkable. I have made inquiry of many practitioners in the Thames valley, where market gardening is the chief industry and where countless tons of London horse-dung are spread upon the land, and learn from them that tetanus is in their experience the rarest of diseases. Seeing that the bacillus is so strictly anaerobic one is justified in sup- posing that the tillage of the soil, which brings it in contact with air and sunshine, must be unfavourable for its growth and virulence. The bacilli must die out under such conditions and the inoculation of the spores alone is said by Vaillard, Kouget and Vincent to be incapable of setting up tetanus. If the bacillus or the spore be carried in dust, or if they be washed into the water and drunk, we have no evidence that any harm results therefrom. In common with some other mi- crobial diseases tetanus is more virulent in the tropics than in temperate climates. Friedberger and Frohner state that it is so common among horses in St. Domingo, especially after the operation of castration, that geldings are worth twice as much as stallions. The statement made by Le Dantec and H. M. Stanley that the natives of the New Hebrides and Central Africa are in the habit of poisoning their arrows by smearing them with mud (obtained in the New Hebrides from a mangrove swamp) gives emphasis to the importance of TETANUS 7 a tropical temperature and the absence of tillage as factors which make for increase of virulence of the tetanus bacillus and other organisms found in earth. Pus from the wound of an animal suffering from tetanus is capable of conveying the disease, and perhaps it is due to this fact that certain stables and pastures have at times acquired an evil reputation in respect of tetanus. Captain Hayes, F.E.C.V.S., is of opinion that wounds in the hoof as the result of careless shoeing are a great cause of what may look like idiopathic tetanus in horses. In an article by Mr. Sidney Villar in the * Journal of Comparative Pathology and Therapeutics ' for December, 1897, an observation by Mr. Joseph Woodger is quoted to the effect that tetanus is particularly common among horses used in dust-carts, and Mr. Villar continues : " In my own practice in Middlesex there are two farms where the disease is specially prevalent. One of these, at Alfreton, is occupied by a farmer who habitually spreads on his fields large quantities of London refuse ; at the second farm, five miles away, the bailiff brought two large loads of the sweepings of London roads in 1893 and dressed his home meadows with it. On these meadows his colts and young stock were pastured and for two and a half years tetanus was endemic on his farm ; during this period six colts became affected and I believe only one entirely escaped the disease." This experience of Mr. Villar seems to point to the danger of placing upon grazing land material which is probably mixed with broken glass or crockery. On clay lands, such as are common in the north of London, manurial matters placed on a pasture would be long in getting incorporated with the soil, and to allow horses to browse amongst the crude impurities of a great city cannot be without danger to the horses. Municipal 8 EARTH authorities who wish to find a ready market for street refuse must clearly take care that it is not mixed with dangerous materials of no manurial value likely to wound the feet of animals. Inorganic refuse, such as old metal, crockery and glass, should be placed two feet beneath the surface, while organic matter should be kept near the surface where it is accessible to tillage. In connection with Marchesi's observation that the tetanus organism has not been found at a greater depth than two metres, I would allude to a fact to which I shall return later, that this approaches the maximum depth to which the earthworm burrows. It is obvious that if a spore were carried downwards by a worm, it would there meet with anaerobic conditions favourable for its preservation. A review of the main facts connected with tetanus cannot but rouse in us some surprise that in the face of the ubiquity of the cause the disease in man should be so rare. This is probably in part due to the fact that we wear boots. ANTHRAX CHAPTEE II A-NTRBAX Anthrax is a disease which undoubtedly is connected with the soil. The bacillus was discovered by PoUender in 1849, a discovery which is just fifty years old and which marks the dawn of pathological bacteriology. The identification of the bacillus in the laboratory, and the diagnosis of the disease in animals from quarter- evil and septicaemia, is not without difficulty. These difficulties are now understood, but they are sufficient to throw a shade of doubt over some of the earlier observations. It may be well in the first place to give some of the facts collected by Pasteur without comment. M. Chamberland, the able assistant of M. Pasteur, in his work ^ gives a resume of what one may call the modern history of charbon. In 1842 a Government report showed that in France the disease raged among the flocks of half-bred merino sheep belonging to farmers in la Beauce. It especially attacked lambs, and the losses in this district of la Beauce amounted to as much as 20 per cent, (out of a total of some 1,300,000 sheep) " et souvent dans les localites dont le sol est sec et calcaire la mortalite va jusqu'au quart, au tiers et depasse parfois la moitie du troupeau." In the depart- ment of Seine-et-Marne and in the districts of Provins, 1 Ijq Charbon, Paris, 1883. lo ANTHRAX Fontainebleau, and Meaux are certain farms known as fermes d charhon — " les meilleurs cultivateurs ne les louent qu'en tremblant." Also in le Cantal charbon is known as * mal de montargnes ' and certain hills are known as 'montagnes maudites' because of their evil reputation in relation to charbon. The animals stricken with charbon show foi' a few days some excitability and passing dyspnoea, and they become distended after feeding. Next the urine becomes bloody, and it is a sign of bad omen to see fleeces spotted with blood. The dung also is noticed to be soft and slimy, of a whitish colour stained with blood. They die at last somewhat suddenly, and in doing so usually void some blood- stained dung and urine, and expel bloody froth from the nostrils. Post-mortem decomposition is rapid, and the animal swells up and blood is expelled from the nostrils. Haemorrhages are found in the skin and cellular tissue, as also in the viscera, which are engorged with blood. The discovery of Bacilli anthracis in the blood clinches the diagnosis. It was in 1850 that Bayer and Davaine described the bacilli, and in 1877 Pasteur com- municated to the Academy of Sciences the important fact of sporulation observed in these bacilli by Koch and himself, and further pointed out that the Bacillus anthracis was essentially aerobic and was quickly destroyed in the blood of the dead animal after the onset of putrefaction. It is important to take notice of the extent to which the ground is soiled by the dung, discharges, urine, and bloody wool of an animal ill with anthrax. In August 1878, M. Pasteur fed sheep on lucerne previously watered with a pure cultivation of B^-cillus anthracis. He says that " in spite of the immense number of spores taken in with the food many of the PASTEURS EXPERIMENTS ii sheep escaped death. . . . The communication of the disease in this way is still more difficult in the case of guinea-pigs." ** Nous n'en avons pas obtenu d'exemple dans d'assez nombreuses experiences. Les spores, dans ce cas, se retrouvent dans les excrements. On les retrouve egalement intactes dans les excrements des moutons." The mortality is much increased when the infected food is mixed with prickly material such as the leaves of thistles and the chopped beards or husks of barley, and the post-mortem examination of sheep rendered * charbonneux ' by fodder of this kind gave reason to suspect that they were in fact really * inoculated ' by definite injury by the prickly food to the back of the throat. Of nineteen sheep fed on lucerne polluted with spores, three died after four, seven, and nine days ; of eleven sheep, fed on polluted lucerne and thistles, three died after three, four, and six days. It is recognised by professional * knackers ' that they run little risk of contracting * charbon ' by manipulating dead animals far advanced in putrefaction, and both Pasteur and Koch have shown that putrefaction soon destroys the bacilli in the blood and tissues of an animal, and that the Bacillus anthracis being aerobic, sporulation does not take place inside the putrefying body, but is very liable to occur in the blood which escapes from it, whether the blood flow upon the earth or upon a dung-heap. In August 1878, Pasteur made a necropsy on the body of a sheep, and then buried the carcass in M. Maunoury's garden. Ten months afterwards Pasteur found spores of anthrax in the earth of this animal's grave, and established the fact by the inoculation of guinea-pigs. The spores were found in the surface soil 12 ANTHRAX over the grave, although since the burial the ground had not been moved. Similarly spores were found in the soil over the grave of a cow buried two years previously, and at a depth of two metres. These spores were found over the graves of dead animals after all the operations of cultivation and harvest. Earth taken at a distance from these graves did not give charbon. In announcing these facts to the Academy of Sciences in July 1880, Pasteur says : ** I shall not be surprised if doubts arise in the minds of the Academy as to the correctness of these facts. It will be asked, * Does the earth, which is so potent as a filter, allow these microscopic spores to rise to the surface ? ' These doubts seem to be supported by facts already published by M. Joubert and myself. We have an- nounced that water from even superficial springs is sterile. . . . These, in spite of conditions above which make for pollution, keep perfectly pure, which shows that a certain thickness of earth arrests all solid particles." Pasteur attributes the uprising of spores to the action of earthworms, and he claims to have actu- ally recovered spores from the bodies of earthworms living in soil polluted with anthrax. *' May not * earthworms,' " asks Pasteur, '* bring other noxious germs to the surface ? They are always filled with a mixture, and the spores of charbon are in them mingled with germs of putrefaction and septic- aemia." Pasteur at this time regarded the earthworm as the great cause of the dissemination of anthrax. In a footnote Pasteur calls attention to the fact that in le Cantal there are pastures which from time im- memorial have escaped {sont epargnees)^ and others in which from time to time the cattle were decimated and EXPERIMENTAL 13 which are known as 'montagnes dangereuses,' which are abandoned without deriving the least profit from them, " at least during several years," says M. Baillet.^ *' This last circumstance deserves great attention. It proves that the cause, whatever it may be, which pro- duces charbon in a locality disappears with time." In la Beauce, Pasteur saw certain fields in which the folding of sheep had been interdicted for several years — i.e., since the last death thereupon from charbon. " Now we placed flocks of sheep on five of these fields, and the mortality was nil except in one flock where it amounted to 1 per cent." M. Colin, of Alfort, a professor at the Veterinary School, not being satisfied with some of Pasteur's ex- periments, a further report was made on May 17, 1881, by a commission composed of M. Bouley, M. Davaine, M. Alphonse Guerin, and M. Villemin. Earth from a twelve-year grave, a three-year grave, and from virgin soil was kept at a temperature of 90° C. for fifteen minutes, and the fine sediment was injected into guinea- pigs. Of five guinea-pigs inoculated with twelve -year earth on March 19, four died on March 21 and 22 from septicaemia, and one died on March 23 from charbon. Of five guinea-pigs inoculated with three-year earth on March 19, four died from March 21 to 23 from septic- aemia, and one died on March 23 from charbon. Of five guinea-pigs inoculated with virgin soil on March 19 none died. One had a small abscess at the seat of puncture. Of six guinea-pigs inoculated with twelve- year and three-year earth on March 30, five died from septicaemia on April 3, and one died from charbon (twelve-year earth) on April 3. Of three guinea-pigs inoculated with excreta taken from the bodies of living ' Mimoires du MmisUre de V Agriculture, 1870. 14 ANTHRAX earthworms, two died from septicaemia and one from charbon on March 30. Of the nineteen animals killed by the above experiments, fifteen died from septicaemia and four from charbon. Since 1879 M. Pasteur had asserted that most soils when inoculated were capable of causing death from septicaemia quite apart from any contamination by the death of anthrax animals. Of three guinea-pigs inocu- lated on March 28 with worm castings taken from above the graves of some of the victims of the Commune situated on waste land, one died from septicaemia on April 1, and two were unharmed. Pasteur had clearly demonstrated that the anthrax bacillus is essentially aerobic, that it is soon destroyed by putrefaction, and that for sporulation free exposure to air and a temperature above 15° C. and under 45° C. are necessary. These facts seem out of harmony with the view that earthworms bring spores from a deeply buried carcass to the surface. The following case is quoted by Pasteur.^ On August 21, 1796, a mare fell dead from anthrax on a causeway {digue) at Houe (Eure-et-Loire). The animal was skinned, and the carcass was dragged by two horses all along this causeway (along which farm animals passed to and fro), with the result that the ground was soiled by the blood and other debris of the dead animal. A large number of the sheep and cows which used this soiled path died. These animals were skinned and buried, with the result that the foci of contamination spread, and ultimately 500 or 600 sheep succumbed to anthrax. The skinning and transportation of an animal dead from anthrax must necessarily be a most danger- ous process. • Annules de V Agriculture, l^re S6rie, tome xxx. p. 332. ANTHRAX LOCALITIES iS All are agreed that anthrax is a disease liable to haunt localities. Thus, in the report of the Board of Agriculture for 1895, I find the following : An undoubted fact in connection with anthrax is its tendency to recur on certain farms. An examination of the agricultural returns received shows that during 1895 the disease reappeared on twenty-three farms or other premises in England and six in Scotland where it had been reported in the previous year. From this cause farms come to be regarded as dangerous, and their value is very greatly depreciated. In a report issued by the German Government,* allusion is made to the farm of Parkisch, where anthrax was rife. " Numer- ous outbreaks of the disease were especially remarked when certain portions of the farm were used as pasture, and when fodder from these portions was used in the stalls. The former tenant of the farm is said to have buried on different parts of the farm carcasses of animals which had died of anthrax, and also to have put the carcasses into the dung-heap to use them as manure." Again, '*Dlouie is a large estate in Kroloen, dis- trict Posen, and is known as a hot-bed of anthrax. . . . It is stated that carcasses of animals which have died from anthrax have been buried with great carelessness on different parts of the fields, especially behind the sheep sheds and in a small wood situated some hundred paces from the farm, which also serves for pasturage, and even in the dung-heaps which together with the straw from under the diseased animals were used for manure." It is alleged by Friedberger and Frohner that the spores may vegetate in the soil and surface water quite independently of the animal body. The disease is said ^ Eepori ojtlfia British Board of Agriculture, 1894. l6 ANTHRAX to occur among horses, cattle, and buffaloes in Eastern Bengal, Manipur, and Burma without the agency of infection and to be in that part of the world a so-called * miasmatic ' disease. As spore formation requires some- thing like a blood heat, it is only what might be expected to find the disease becoming endemic among cattle and horses in tropical countries. Where infected animals drop dung and other discharges on the soil it becomes impossible to say whether the infective spore originates in the soil or in the animal. The distinction which separates soil from dung is somewhat subtle. These authors assert that '* there exists a well-marked connec- tion between the disease and the amount of moisture in the soil. It appears most frequently in lowlands and plains exposed to inundations and great heat." Copeman also asserts that the disease is prevalent on damp soils containing much humus, as, for instance, upon peat bogs and near the borders of lakes and rivers which have overflowed. On the other hand, we have Pasteur speak- ing of montagnes maudites in connection with anthrax and asserting that the mortality is great in soils which are sees et calcaires. Many of the outbreaks of anthrax in this country have been in the neighbourhood of Bradford and have been traced to the use of infected wool-refuse as manure. A map published by the Board of Agriculture shows that the outbreaks of anthrax are most frequent in those counties of Great Britain where dry foreign wools, hairs, hides, and skins are manufactured into goods. In 1892 there were forty-two outbreaks of anthrax in the West Biding of Yorkshire, as against two in the North Riding and one in the East Riding. Wool when used as a manure must take a long time in becommg disintegrated and humified. In this respect it is very different from IVOOL SORTERS' DISEASE 17 dung, and if wool be infected with anthrax spores it must be a very dangerous manure for a pasture. The chief sources of danger are said by Dr. Bell, of Bradford, to be the dry wools of goats, alpacas, and llamas which are im- ported very dry from hot countries. It is the anthrax spore which is the danger, and if, as is the case, a high temperature and free admission of air be necessary for sporulations an excess of water would be unfavourable for that process. There seems a concurrence of opinion that the Bacillus anthracis is killed by putrefaction and soon disappears in the unopened and unskinned body. Schmidt-Miihlheim inoculated guinea-pigs with anthrax and as soon as they were dead he skinned them and placed the limbs in an incubator at 39° C. The surface of the flesh was soon covered with a whitish film which was found to consist exclusively of anthrax bacilli, in many of which commencing spore formation was apparent. There can be little doubt that the soil becomes infected by the discharges from the living animal and the skinning and other manipulations of the dead one. The advice which is usually given in this country to bury anthrax carcasses deeply and unopened and unskinned is doubt- less sound, although it is open to question if the depth of the grave adds materially to the anaerobism of the surroundings. It is very doubtful if in an unopened body spore formation be possible after a short period of burial. It is clear that the animal should be buried at the spot where it dies and that the spot should be enclosed and planted with a few saplings of some indigenous tree. The value of ' quicklime ' is doubtful. Whether it be advisable to delay burial until quicklime can be obtained is still more doubtful. All Pasteur's experiments in relation to graves appear to me to be vitiated by the fact that they took i8 ANTHRAX place in an anthrax district, and it is very difficult to say whether the spores were derived from the buried animal, or from the dung of infected ones which had been used as manure, or from the blood-stained wool which, we are told, is of * bad omen ' in a flock. It is a noteworthy fact that of the nineteen guinea-pigs inocu- lated by the Alfort Commission four only died from anthrax and fifteen from septicaemia, and that the earth from the three-year-old grave and from the twelve-year- old grave conveyed anthrax in the same proportion — i.e. one in four inoculations. There seems no doubt that spores may be found in earthworms or their castings, and there is equally no doubt that if the worms have brought the spores from the depths of the earth such spores must have originally been formed on the surface. It is, of course, quite impossible to say whether a worm swallowed the spore on the surface or below it. It is certain that recently-dead bodies have no attractions for worms. Such carrion usually forms the food of maggots hatched from the eggs of diptera deposited before burial, and of beetles which live in the earth, and are soon attracted to it. There are some discrepancies amongst observers as to the infectivity of food grown on anthrax ground. On the one hand, Pasteur was unable to do much harm to sheep fed on lucerne sprinkled with spores, and on the other hand, we have a story quoted by Pasteur of an old woman whose goat and cow died from anthrax when fed with clover stolen from over a grave two years after the burial of an anthrax animal. It is, of course, im- possible to get away from the 2?os^ lioc fallacy in these cases, especially in a country where animal hygiene was utterly neglected, and where anthrax was, or diseases resembling it were, rife. In this country we have had SHEEP AND ANTHRAX 19 no outbreaks of anthrax at all comparable to those which have proved such a scourge in France and other parts of the Continent. The loss of sheep from anthrax in England is very slight, and the explanation is probably to be found in the relative vulnerability and immunity ^ of the flocks. Sheep in England are rarely housed, but are allowed to breathe at all times the freshest of fresh air. Their pastures are changed before the ground gets foul, and when food is short they are either killed at once or fed upon imported food. Such a condition of things would be likely to breed immunity to disease of all kinds ; and it is noteworthy that tubercle is much less common among sheep than amongst ani- mals which are housed. When flocks are kept partly for dairy purposes, and when sheep are housed and breathe a foul air, and lie upon filth mixed with earth, it is no wonder that disease, especially such a disease as anthrax, is liable to be rife and to be difficult to eradicate. Anthrax in the human subject is a rare disease. Man is never infected through the alimentary tract as appears to be the rule among animals. Dr. Bell, of Bradford, says that ** no such case has been recorded in this country." Cutaneous anthrax (malignant pustule) is caused by direct inoculation. It occurs (1) in those who come into contact with infected animals alive or dead ; (2) in those who handle offal, skins, hoofs, horns, hairs, wools or other derivatives from such diseased animals ; and (3) in countries where the disease is ^ Algerian sheep are immune to anthrax. See Chauveau, * Nature de rimmunite des Moutons Alg^riens centre le Sang de Kate. Est-ce une aptitude de race ? ' (C. B. Acad. Sc. xcl. 1880) cited by A. Billet in 'Contribution a I'Etude de la Morphologic et du D6veloppement des Bacteriac6es,' Paris, 1890 (with other references). c 2 20 ANTHRAX common among animals, women and children who do not come into direct connection with infective material are not infrequently attacked with the disease through the medium of persons, animals, or insects. Pulmonary anthrax or wool-sorter's disease was first noticed in the Bradford worsted district after the intro- duction of alpaca and mohair as textile materials in 1837. " This form of anthrax may attack any person exposed to the inhalation of anthrax spores in dust arising from the products of diseased animals." The fact appears to be undoubted that anthrax may be a dust disease and that the spores when perfectly dry may be inhaled into the lungs. And yet I have hitherto found no records of pulmonary anthrax from the in- halation of dust from highly manured ground which must, one would suppose, especially in the West Eiding of Yorkshire, often contain anthrax spores. The lungs of the agricultural labourer and the market gardener appear to be immune to the infectivity of anthrax spores. It seems to be of very great importance to bear in mind : (1) that anthrax spores persist even in the finely pul- verised soil of worm castings, which must be very easily dried and converted into dust ; (2) that anthrax may undoubtedly infect man by the inhalation of dust ; and (3) that pulmonary anthrax among agriculturists has not been recorded. In India it is believed by some that dust is a common cause of enteric fever among Euro- peans, a statement which is insusceptible of proof or of disproof. Does pulmonary anthrax occur among the rural population of the tropical countries where the disease is endemic amongst cattle ? In this connection we must bear in mind that anthrax bacilli may change their virulence without undergoing any morphological changes, and in this form when inoculated may confer VIRULENCE 21 immunity on susceptible animals without apparently producing other effects. The virulence is diminished by cultivation at high (from 108° to 120° F.) or low (from 66° to 75°) temperatures, by cultivation under pressure of three or four atmospheres, by exposure to sunlight, or by admixture with other bacteria. The modified organisms thus produced are not pathogenetic but confer immunity on susceptible animals for nine or twelve months. Morphologically they are indistinguish- able from the most active and virulent forms of the organism, and they will generally regain their virulence when favourable conditions are restored, although the degree of virulence varies in different species of animals. The persistence of the anthrax spore in the earth does not admit of a doubt, but there is no evidence that man is ever infected directly from the earth. How far anthrax in animals is due to inoculation rather than to feeding requires further and very careful investiga- tion.^ * Pictet and Yung by a special process have subjected bacteria to a temperature as low as - 130° Centigrade, without killing some of them, for instance anthrax spores. (G. von Bunge, Physiologie des Menschen, vol. i. 1901, p. 283.) 22 DIARRHCEA CHAPTEK III DIABEHCEA-DYSENTEBY—CHOLEBA DiARBHOEA is a diseasG which in its epidemic form has been supposed to be engendered in the earth. The third quarter of the year 1898 ^ was character- ised by a very large infantile mortality, mainly attri- butable to diarrhoea. The rainfall for the quarter was unprecedentedly small, the temperature was above the average, and the harvest was one of the best on record. Of the 141,540 deaths registered, 52,837 were those of infants under one year of age. The mortality of infants, measured by the proportion of deaths under one year of age to registered births, was 225 per 1,000, which is the highest proportion in any quarter for which the figures are available, and is 55 per 1,000 above the average in the ten preceding third quarters. In the thirty-three great towns as a whole, infant mortality was equal to 275 per 1,000 births, being higher than the proportion in England and Wales by 50 per 1,000. Excluding the towns, infant mortality in the re- mainder of England and Wales was in the proportion of 184 to 1,000 births. Diarrhoea caused 22,524 deaths, equal to an annual rate of 2*85 per 1,000, or 1*21 above the average rate of mortality in the third quarters of the previous ten years. The death-rate from this disease ranged from 0*7 in * Quarterly Eeturn of the Begistrar-General. DIARRHCEA 23 Kutlandshire, 0*58 in Hertfordshire, 0*66 in Shropshire, and 0*68 in Dorsetshire, to 3*63 in Leicestershire, 3-70 in Staffordshire, 3*94 in Lancashire, 4*23 in the East Riding of Yorkshire, and 4*40 in Warwickshire. Among the thirty- three great towns the diarrhoea rate averaged 3*85 per 1,000, the highest rates being 5*85 in Hull, 5-94 in Sunderland, 6*30 in Sheffield, 6*38 in Wolver- hampton, 6-41 in Preston, and 6*47 in Salford. In the sixty-seven other large towns the rate averaged 3*27 per 1,000. In the rest of England and Wales the diarrhoea death-rate was equal to 2*07 per 1,000. It will be observed that the mortality from diarrhoea was mainly urban. Among counties it is the rural counties which have least and the industrial counties which have most diarrhoea, and if we turn to the mor- tality returns for those counties where diarrhoea was especially rife, we shall find the mortality greatest in the urban districts. It is a point not without interest to note that the diarrhoea death-rate and the fever death-rate in this quarter bore no relation to each other, and that, while the diarrhoeal death-rate was 1-21 above, the fever death-rate was 0*03 below the average for the corresponding quarter of the last 10 years. In the following table some figures are collected which show this very strikingly : Table showing the Death-rates per 1,000 frorn Fever and Diarrhoea during the Third Quarter of 1898. - Fever Diarrhoea England and Wales . London Wolverhampton Leicester Manchester .... Preston 016 Oil 0-18 013 0-09 0-28 2-85 3-19 6-38 5-34 5-38 6-41 24 DIARRHCEA Diarrhoea is a disease of hot weather, when there is special liability to sour milk, rancid butter, stinking fish, high meat, and rotten fruit. Ballard thought that when the four-foot temperature of the earth reached 56° F. diarrhoea became common. Tomkins, of Leicester (Leicester is a * diarrhoea town '), showed that the disease became common when the one-foot thermo- meter stood at 60°. Snow, of Buffalo, U.S.A., showed that in 1886-88 diarrhoea mortality was highest when the minimum atmospheric temperature attained its highest average range. The London statistics for 1887 and 1888 collected by Dawson Williams show a similar relationship between diarrhoea and a high average minimum range of temperature. Copeman considers it highly probable that the disease is due to * microphytic processes ' going on in the upper layers of the soil. This would afford an explanation of the fact that summer diarrhoea is especially a disease of cities having a polluted soil. Ballard's conclusions (as given by Copeman) were : " That the essential cause of diarrhoea resides ordinarily in the superficial layers of the earth, where it is intimately associated with the life processes of some micro-organism not yet detected, captured, or isolated. That the vital manifestations of such organism are dependent, among other things, perhaps principally upon conditions of season and on the presence of dead organic matter which is its pabulum. That on occasion such micro-organism, capable of getting abroad from its primary habitat, the earth, and having become air-borne, obtains opportunity for fastening on non-living organic material and of using such organic material both as nidus and pabulum in undergoing various phases of its life-history. That in food, inside of as well as outside of the human body, such micro-organism finds, especially at certain seasons, BACILLUS ENTERITIDIS SPOROGENES 25 nidus and pabulum convenient for its development, multiplication, or evolution. That from food, as also from the contained organic matter of particular soils, such micro-organisms can manufacture by the chemical changes wrought therein through certain of their life- processes a substance which is a virulent chemical poison (probably ptomaine). That this chemical sub- stance is in the human body the material cause of epidemic diarrhoea." It is most important to remember that these specula- tive notions of Ballard's are not facts. The Bacillus enteritidis sporogenes is believed by Klein to be the cause of infantile diarrhoea.^ It is an anaerobic bacillus which forms spores, and may be easily cultivated in milk. It is fatal to rodents when injected hypodermically, and produces a foul-smelling bloody oedema of the cellular tissue and adjacent muscle tissue. The spores were found in four out of ten cases of infantile diarrhoea examined, and in six out of eight cases of cholera nostras. It was found in eight out of ten samples of milk purchased in London milkshops between April and the end of June (when diarrhoea was not epidemic?) including samples of so-called *pure sterilised milk.' It has been found in large quantities in sewage and in sewage effluents. It is found in horse- dung, and in all matters polluted with it. It has not been found in pig-dung or cow-dung, or in the dung of a healthy human being. In face of the wide distribution of the microbe, it is evident that the vulnerability of the individual must be an important factor in determining an attack of diarrhoea. If we are to consider diarrhoea as a soil disease it is evident that it exists only in the upper layers. It is • Twenty-seventh Local Government Eeport, 1897-98. 26 DYSENTERY more common among city streets than in agricultural districts. According to Klein, the probable cause is largely to be found in horse-dung which is pulverised and blown about generally. Temperature, as we all know, is most potent as a cause of infantile diarrhoea in cities. That it is a * soil ' disease in any true sense is certainly not proven. Dysentery Andrew Davidson ^ says : — "In keeping with the predilection of endemic dysentery for marshy localities, accounts of its endemo-epidemic extensions in temperate climates generally point to the temporary establishment of paludal conditions." Thus in 1873 an outbreak arose from the cleaning out of the lateral canal of the Loire and the desiccation of the mud. A similar result followed at Leymen (Haut-Rhin) from the clearing out in August, 1850, of a vast slimy reservoir situated in the middle of the village. In tropical countries dysentery appears to be more independent of soil than in temperate climates, but an imperfectly- drained or marshy soil is everywhere favourable to its prevalence. The geological nature and the mineralogical constituents of the soil are secondary in importance to its physical conditions — its dryness, humidity, and aeration. These again are of less moment than its state of organic purity. That a soil charged with dysenteric or perhaps even with faecal (simple faecal) evacuations is capable of giving rise to the disease is amply proved. The epidemics which occurred in the Cumberland and Westmorland Asylum in 1864-65 and in 1868 were shown by Dr. Clouston to be in part due to the effluvia from a stiff clay field over which the sewage of the asylum was allowed to flow. • AlXbutV^ System of Medicinet vol. ii. p. 408. ASYLUMS, WAR AND FAMINE 27 The soil was quite unfit for irrigation purposes. Dysen- tery is very common in asylums, a fact which is probably due to the infectivity of the excreta and the dirty habits of lunatics. Among the causes of the frightful dysentery mortality which made Secunderabad a byword, none was more effective than the saturation of the soil of the site itself with organic impurities, the extreme pollution of the vicinity with faecal matters, and the bad privy accommoda- tion. The dysentery of war and famine shows little respect for climate or season ; under the given conditions it appears in countries most free from the endemic disease, and at all seasons of the year. The dysentery of war and famine is extremely fatal, and it has a greater tendency than any other to become complicated with typhus, typhoid, and malarious fevers. In the Irish workhouses during the ten years ending June, 1851, no fewer than 50,019 persons perished from dysentery, and 20,507 from diarrhoea. The dysentery of war and famine frequently assumes a contagious character. The bacteriology is rather uncertain owing to the numbers and variety of the micro-organisms which are found. Davidson concludes : (1) The healthy intestine is capable of much resistance to the infective agents of dysentery. (2) The healthy human being carries with him organisms capable under certain conditions of giving rise to inflammation of the intestinal tract, and besides organisms of suppuration, putrefaction, and sepsis are everywhere present which have the power of determining dysenteric inflammation of the bowels when their nutrition is impaired. (3) A simple catarrhal con- dition of the bowel is sufficient in itself to produce true dysentery. (4) When we observe a body of men seized with an infectious form of dysentery immediately after being subjected to hardship and depressing meteoro- 28 CHOLERA logical influences, while another body in the vicinity having the same food- and water-supply but not sub- jected to the like fatigue and hardships escape, we are led to infer that the common exciters of inflammation rather than any specific agent must have given rise to the disease. Cholera Ernest Hart says : * Within certain areas in India cholera is endemic, especially in the country of the lower Ganges. There the air, the water, and the soil are never cold, the ground is often damp, and when it is dry the tanks are foul, so that there is always a fit breeding-place for the contagion, &c.' Koch's vibrio (Kanthack) grows in dilute peptone at from 30° to 35° C. It is commonly said to be destroyed by drying. It is a facultative anaerobe and highly saprophytic. Cultures retain their vitality on silk threads for eighty- six days and dried on glass for 120 days. *' From flies fed on choleraic material the vibrios could be separated after fourteen days." The inoculation test practised on the lower animals is inconclusive. According to Petten- kofer (quoted by Copeman) cholera occurs when the ground-water after having attained a higher level than usual commences again to fall. MALTA FEVER 29 CHAPTER IV MALTA FEVEB-PLAGUE-^DIPHTHEBIA Malta fever ^ is caused by the Micrococcus melitensis discovered by Bruce in 1887. It is common to the shores of the Mediterranean and Red Seas. " It was early apparent that its presence in Malta and Gibraltar was connected with faecal and organic matter from human sources. Sewers and sewage works where these have been undertaken, as in Valetta and Naples, appear to have little influence in diminishing the attacks. Indeed, the channels are so frequently pervious and allow the faecal matter to soak into the pores of the soil that they virtually become elongated cesspools and increase rather than diminish the dissemination of the poison. Tomaselli notices the same fact in relation to the prevalence of the fever and the introduction of sewers into Catania. In his opinion the immense quantity of sewage and sewer air which is developed in these sewers and finds its way out of them is to be placed in the first rank of its causation and is an argu- ment in favour of the aerial dissemination of the morbific agent. The micro-organism grows best in nutrient material the alkalinity of which is slightly less than human blood and at a temperature of from 37° C. to 39° C. It fulfils Koch's postulates at all points. It lives for a long time in the dry state." ' AllhutVs System of Medichie, vol. ii. p. 463, by Lane Notter. 30 PLAGUE Plague Plague has been regarded as a soil disease, but recent evidence must materially modify this opinion. The alleged facts which support this view are, according to J. F. Payne in his article on Plague in * AUbutt's System of Medicine ' : (1) its limited geographi- cal distribution ; (2) because ground animals such as rats perish in large numbers — " they have buboes and their organs contain immense numbers of the plague bacilli ; it cannot therefore be doubted that the virus exists underground before it affects human beings"; (3) its recurrence at the same spot while places near and in direct communication escape ; (4) the escape of water populations such as in Canton and in London in 1665 ; (5) the fact that the ground floor is affected more than the first floor — *' Plague does not go up- stairs " (?) ; and (6) " the beneficial effect of local sani- tary measures." It would appear from the above reasons that the endemic prevalence of plague is comparable to that of cholera or typhoid fever and is governed by somewhat similar laws, though in other respects it differs very much from those diseases. In the double infection of the soil and the organism it resembles anthrax. Along with the infection of the soil there appears to be a passage of the virus in some form into the air, so that it has always been believed that the disease may be acquired by inhalation like typhus fever. Scientific explanation of this method of receivmg the virus is still wanting. Epidemics have often been preceded by drought ; epizootics, famine, and abundance of flies have been noticed. Epidemics are usually checked by cold and heat. It is pre-eminently a filth disease, VIENNA CASES 31 invading by preference the crowded, ill-ventilated hovels of the miserable. " A soil contaminated with faecal discharges and decaying animal matter of all kinds appears to be an essential condition for the vitality of the virus." Widely different opinions have been held as to its * contagiousness.' " The infection is doubtless generally conveyed by persons either infected with the disease or in the state of incubation. Such persons convert the house they occupy into a focus of infection till possibly the virus passes into the soil and a severe epidemic may result." The rate of extension is variable but generally slow ; plague has taken weeks or months to pass from one side of a city to another ; it creeps along from point to point so as to be com- pared by some to a drop of oil on paper. Such gradual extension suggests the slow progress of a virus in the soil itself, and probably that is in some places the explanation, but obviously only transmission through short distances can be thus accounted for. It is encouraging to observe how the habit of calmly observing and recording the phenomena of different epidemics together with carefully devised experiment has thrown light upon many of the obscure points connected with plague. We now know that plague is protean in its forms and that all forms are not conveyed from individual to individual with equal readiness. The unfortunate accident which occurred in 1898 in Vienna ought to have, and doubtless has had, the effect of dispelling many of the superstitions in regard to plague. It has clearly demonstrated to the people at large (1) that the poison is something tangible which may be conveyed from one part of the world to another in a test-tube ; (2) that the poison may infect the lower animals ; (3) that the lower animals may infect man ; 32 PLAGUE (4) that the pulmonary form of the disease is terribly infectious and communicable through the air ; and (5) that measures of disinfection and isolation are capable of cutting short an epidemic. Experiments carried out in districts where a disease is epidemic or endemic necessarily acquire a measure of uncertainty from that fact alone. The occurrence at Vienna, much as one may deplore it, was an object-lesson of the greatest value and converted what many regarded as mere theories into facts which all can read and under- stand. In the recent epidemics in the East the theory that plague grows * in the soil ' has received no support whatever, and that it spreads in the soil like a drop of oil permeating paper appears to be unlikely. In India two facts have come to the front — viz. the danger in rela- tion to plague of (a) rats and (b) abrasions on the skin. The rat lives in burrows in the soil and swarms in our sewers. He feeds largely at night and comes out of his hole in search of food and prey. It has long been recognised that the rat is susceptible of plague. In Bombay, according to Simpson, as many as 100 affected rats were counted in one small grain depot in one day. Hindoo writings 800 years old warn the inhabitants to leave a district when they observe a mortality among rats. The infection of rats usually follows infection of a distant locality by men. Nowhere has this been more decidedly proved than during the epidemic in India, where the infection of the rats has unfortunately followed the introduction of the virus by man, from a primary seat of infection situated at considerable dis- tances from the secondary area of infection. Eats may convey infection from infected burrows on their feet or fur ; they also become infected by eating each other. When dying they usually leave their holes and run RATS 33 about the rooms of a house and then die. Carelessness in dealing with or handling them, especially in the filthy surroundings and associated with the dirty habits of the inhabitants of these houses, along with the pos- sible convection by vermin, must all necessarily be in favour of the infection being carried to man. The amount of such infection spread by rats cannot be gauged. The infection of the rat is no proof whatever of infection of the soil except by filth deposited on the surface. Lowson in his report to the Bombay Govern- ment in 1897 says : " That the disease is primarily a soil disease is certainly borne out neither by observa- tion nor experiment. Takaki and I carried out bacterio- logical experiments in Hong-Kong by which we were able to prove that even in houses in which the earthen floors had been severely infected no cases of plague infection could be obtained, and later experiments on the artificial infection of earth with a culture of the plague bacillus have shown that the mixture of earth and bacilli loses its infecting power, sometimes in a couple of days." Indeed, there has been no proof forth- coming so far that the plague bacillus has ever been found below the surface of the earth. In Hong-Kong the soldiers who were attacked by plague were in the cleansing squads, and were well booted, but worked with trousers open at the bottom. In India the military parties who assisted in this work were ordered to wear putties to prevent plague-infected dust and animals from coming in contact with their legs, with the result that none of those engaged in this work became infected, and that, too, amongst probably eight or ten times more soldiers than were doing the work in Hong-Kong. To sum up, it may be said that the following are the most important items in the spread D 34 DIPHTHERIA of plague : (1) filthy habits of the people, such as spitting over the floor and others mentioned above ; (2) filthy houses ; (3) overcrowding and consequent rapid increase of contagious disease when once imported ; (4) presence of rats, insects, and other vermin ; (5) the naked con- dition of the people going about, such people presenting almost unlimited opportunities for the entrance into their tissues of plague poison by inoculation and through abrasions ; (6) pollution of soil and houses with the excretions of man and animals ; and (7) filthy clothing and absence of bodily hygiene. Diphtheria With regard to diphtheria, Arthur Newsholme in his work on * Epidemic Diphtheria ' (1898), while admitting that personal infection is the chief means by which diphtheria is spread, contends that : The specific micro- organism of this disease has a double cycle of existence, as have the specific micro-organisms of enteric fever, erysipelas, scarlet fever, rheumatic fever, &c. One phase is passed in the soil, another in the human organism. One is saprophytic, the other parasitic.^ It is not strange, therefore, that the epidemic prevalence of all the above diseases is favoured by deficient rainfall if this is sufficiently long continued. This deficient rainfall implies a low subsoil water and a subsoil above the level of this water which is relatively dry and warm, probably the optimum conditions of the saprophytic life of the above pathogenic micro-organisms. The causes of the transition of the diphtheria bacillus from the saprophytic to the parasitic phase of life may be sur- ' It is not contended that there is a regular alternation of sapro- phytic and parasitic generations ; but that such alternations do occur. SEASON 35 mised both as regards {a) season and (6) years of special epidemic prevalence. Diphtheria is most pre- valent in the autumn and early winter months, when the optimum temperature and the optimum degree of humidity of the soil are rapidly disappearing or have departed. It is also most prevalent after the wet weather, occurring in, or immediately following, excep- tionally dry years. Both these conditions tend to raise the ground water and to drive out any pathogenic micro- organisms from the soil. Newsholme is of opinion that in order to account for the epidemic and even pandemic waves of diphtheria, the diphtheria bacillus under certain conditions becomes more actively virulent and infective — more remote from its saprophytic phase of life, and that thus persons who can resist the ingress of the feebler fall victims to the more powerful micro-organism. The latter is probably the correct hypothesis, and the evidence already given clearly points to the conclusion that of the external cultural conditions leading to increased virulence of the diphtheria bacillus and greater readiness for assum- ing a parasitic life, exceptional deficiency of rainfall and consequent exceptional deficiency of moisture in and exceptional warmth of the subsoil form an essential part. The above is a very ingenious hypothesis, but it is essential to point out that the diphtheria bacillus has not been recovered from the soil and that the bacilli of rheumatic fever and scarlet fever have not yet been identified.^ Before Newsholme's hypothesis can be accepted a great deal more evidence will be necessary. ' Poynton and Paine have isolated a diplococcus in rheumatic fever, which may turn out to be the specific micro-organism. {Path. Tra/ns. vol. lii. 1901, p. 10, and other p^^pers.) D 2 36 DIPHTHERIA Newsholme's figures and tables show clearly that the amount of diphtheria is very great in the American cities. He records death-rates (per 100,000) for diph- theria of 109 in New York (average of 28 years, 1868- 95), 77 in Chicago (36 years, 1859-94), 100 in Boston (35 years, 1861-95), 114 in Brooklyn (1875-95), and 129 in Pittsburg (1877-94.) The highest death-rate from diphtheria ever recorded in London was 76 (per 100,000) in 1893. The average death-rate per 100,000 was in Salford 32 (1860-95), Manchester 18 (1871-96), Liverpool 14 (1860-95), and Sheffield 15 (1859-96). The figures were still lower in others of our great industrial towns. In Holland we find death-rates per 100,000 from diphtheria alone of 7 in Eotterdam, 12 in The Hague, and 31 in Amsterdam (all three for 1879- 95). Berlin gives 101 (1869-96), St. Petersburg 65 (1879-95), and Moscow 64 (1878-96). The death-rate in Japan appears to be low. Newsholme's figures generally seem to show that diphtheria is now a disease more of the towns than of the rural districts. It is not very easy to understand how in a city where pavements and other impermeable coverings to the soil are general, the bacillus is driven by the rising subsoil water into the air. Of course, it may be driven out of the sewers and sewer ventilators, in which case it becomes a sewer disease rather than a soil disease. Why is it not an air disease? Nobody who has ever smelt the air of Bond Street in a hot July, or who has watched the impurities descending from the upper air when they are driven downwards by the first showers after a drought, would refuse to allow to the air of a city any amount of potential infectivity. Most of the facts collected by Newsholme are explained as readily, if not more readily, on the theory that diphtheria is an SOIL 37 air disease as upon the theory that it is a soil disease. If we remember that a theory is not a fact these specu- lations will do no harm. Unfortunately this is not always remembered. Diphtheria (Copeman) has been supposed to show a preference for houses on damp clayey soils (Greenhow, Airy) and dampness of habitation (Thursfield). *' Although," says Copeman, ** dampness of site is undoubtedly a factor in the production of out- breaks of diphtheria, particularly if such dampness be due to persistent leakage from imperfect sewers or cess- pools," it does not appear to bear any relation to the rise and fall of the subsoil water. That diphtheria is a soil disease is certainly not proven. 38 MALARIA CHAPTER V MALARIA— BLACKWATEB FEVER— TSETSE- LOUPING ILL— TEXAS FEVER— HORSE SICKNESS A FEW years ago I should have spoken of * malaria ' as undoubtedly caused by something in the soil itself, and I should have indulged in the stock phrases about miasmata, mephitic vapours, and the like. The dis- covery of hsematozoa in the blood of sufferers from malaria has altered our point of view. The most widely spread poison in the world has become something which is visible and tangible and inoculable. No discovery which has ever been made in the domain of medicine is likely to have such far-reaching effects. Further, it seems certain that the infection of human beings may take place via the mosquito, and we are now concerned to find out whether this is or is not the only medium through which the blood of man receives the parasite. Some who are well qualified to speak would answer in one way and some in another. This is not the place for weighing arguments pro and con, nor can I claim any special knowledge which qualifies me to sit in judgment. Let us assume that it may possibly be shown hereafter that what we have hitherto regarded as ' malaria ' is a parasitic disease wholly and solely inoculated in us by insects of the mosquito class. While on the one hand we may be able to show Europeans the importance of MALARIA AND CULTIVATION 39 protecting themselves against the attacks of insects, we must still continue to make use of our accumulated knowledge as to the conditions of soil which indirectly cause remittent fevers to be endemic, and which favour the increase or decrease of mosquitoes by facilitating or otherwise the formation of breeding pools. Old and well-established facts will now be re-examined by intel- lects strengthened and widened by the discoveries of Laveran and Boss, and our knowledge is sure to be extended and increased. Although the conditions of soil which give rise to malaria are too well known to need any lengthy dis- cussion here, it may be well to give some of the latest utterances on the subject. Sir Joseph Fayrer, writing on the * Climate and Some of the Fevers in India,' in * Allbutt's System of Medicine,' * says of malaria : " It often appears with great virulence after excavation or turning up of soil, and in land-that has recently been denuded of jungle." ..." On the other hand, draining and cropping seem after a time to diminish or destroy the poison. Maclean calls attention to the fact that when excavations were made in the island of Hong-Kong, which consists entirely of weathered and decaying granite, and is liable to be permeated with a peculiar fungus, violent and fatal remittent fever appeared." Osier says: '*An interesting feature in connection with the disease is the gradual disappearance from certain regions under the influence of drainage and cultivation. In England, even in the fen country, it is now almost unknown. In New England, too, it has gradually disappeared. In parts of Canada bordering Lake Ontario which were formerly hotbeds of the > Vol. ii. p. 311. 40 BLACKWATER FEVER disease cases only exceptionally occur." It is well called a soil disease. " Excavations of all sorts, extensive cuttings for railways, and the breaking up on a large scale of virgin soil have in many instances been followed by outbreaks of malaria." ^ The greater prevalence of fever in the Koyal Engineers in com- parison with other troops is probably to be accounted for by their more frequent employment in the excava- tion of the soil. Manson,^ speaking of Eoss's work in connection with the mosquito, says that although he believes that malaria may be acquired by the bite of the mosquito, he does not believe that this is the only way. Eees,^ of the Seamen's Hospital, gives details of an outbreak of intermittent fever (confirmed by examination of the blood by himself and Manson) which affected twenty-two of the crew of a ship nine days out from Colombo and fourteen from Calcutta on her homeward voyage. Air-borne infection or water- borne infection cannot be lightly dismissed. As to blackwater fever, Crosse, writing on the subject,^ says : ** Some will ask, Why has blackwater fever become so common recently ? The first case on record in the Niger Territory was, so far as I know, my own, ten years ago. The first case on the Niger Delta is said by some old coasters to have occurred in 1882. It seems to me that since we have begun to turn up virgin soil for coffee and other plantations the disease has become common. ... It is significant that our first three gardeners died of blackwater fever, and * I recently discussed this subject with two gentlemen who were intimately connected with Indian railways, and who professed ignorance of any danger arising from recent cuttings. 2 Brit. Med. Jour. Sept. 24, 1898. « Ibid. Sept. 24, 1898. * Ibid. Oct. 8, 1898. SOIL AND MOSQUITOES 41 that for some considerable time cases only occurred near the plantations, and as plantations became common so the disease spread to the other stations in the territories. Castellote notes a case in which a white man personally superintended the digging of a grave and stood about in the sun for two or three hours ; next day he had severe fever which developed into blackwater fever." According to Batter sby, " many virulent attacks after the turning up of virgin soil have been recorded." Almost equally remarkable, according to this observer, is the diminution of the disease which has been brought about in certain localities by drainage and cultivation of the soil. It is generally conceded that the turning up of virgin soil is one of the most fruitful causes of malig- nant malarial fevers, and numberless examples of this are given in text-books on the subject. Surgeon Bowden, E.N., D.S.O., informs me that the turning up of fresh soil is often followed by an influx of mosquitoes. On the other hand, the cultivation of the soil seems ultimately to lead to the decrease and disappearance of malaria. The broad facts of Nature must convince us that this must be so, for if man in his attempts to grow food merely increased the deadliness of his surroundings, the human race would soon become extinct. There is a group of diseases which (like malaria) seem to be dependent upon the bites or stings of insects, and which, although they affect animals rather than man, throw much light upon the pathology of infection, and teach us that so-called ' climatic diseases ' may be due to something very gross and palpable. 42 TRYPANOSOMA Tsetse Fly Disease Kanthack, Durham, and Blandford ^ have shown that Ngana or tsetse fly disease is due to a hasmatozoon (trypanosoma) in the blood inoculated by a fly. Cats, dogs, mice, rabbits, rats, hedgehogs, donkeys, horses, and their hybrids seem susceptible. The disease appears to be communicable only by some form of inoculation and is not probably conveyed by feeding on infective material in the absence of superficial lesions. Material taken from the dead body twenty-four hours after death is not infective. The nearest lymphatic glands to the inoculated spot are the first to suffer. The haematozoon gets through the lymphatics to the blood. In the late stages of the disease the animals (especially dogs) may become infected by pyococci, i.e, a spon- taneous infection to which the animal is rendered prone by its marasmus. The blood may contain 3,000,000 haematozoa per millimetre, or may prove infective though none be visible. The trypanosoma sanguinis which is found in a certain proportion of rats has no apparent relation to tsetse fly disease. A similar parasite is said to cause * surra ' in India and an allied disease among horses in Algeria. Surra is probably conveyed by flies. Lingard thinks the fodder soiled with rat-dung may give the disease, but that is doubtful. The tsetse fly is a dipterous insect somewhat resembling the common house fly. It has a long thin proboscis, chestnut thorax marked longitudinally by four black lines, and a yellowish-white abdomen of five rings. It inhabits principally the low-lying and swampy valleys of the Zambesi and Chobe. ' Proceedings of the Royal Society, vol. Ixiv. p. 100. TICKS 43 LoupiNG III * Louping ill,' which is common in the North of England and Scotland, and which has been noticed as fatal to sheep frequenting certain pastures, has now been shown by Williams, Meek, and Greig Smith ^ to be caused presumably by a special kind of sheep ' tick ' found on these pastures, which tick is supposed to be hatched in the upper layer of the soil, and to inoculate the sheep with micro-organisms which cause the disease — a disease which is characterised by staggering and lameness, due to congestion of the brain and spinal cord, which have been found post mortem. Texas Fever Texas fever of cattle appears to be caused by a hsematozoon with which the animal is inoculated by a tick (Ixodes or boophilus bovis) which is parasitic. The Australian tick fever and the ixodic anaemia of Jamaica appear also to be produced by allied if not identical parasitic animals. Principal Williams, F.K.C.V.S., of the New Veterinary College, Edinburgh, in writing on ixodic anaemia or Texas fever ^ (which he studied in Jamaica), which is due to the infection of cattle with a blood parasite by the agency of a tick (ixodes bovis), insists that every attempt should be made to get rid of the ticks, which breed especially in the vegetable rubbish left upon the pastures. ** Every effort should be made," he says, "to conserve and increase tick destroyers such as the black tick birds. ... I have had much amusement in watching these birds, as there seems to be ^ YeUrinarian, 1896-97. 2 'Pryyici'piQs and Practice of Veterinary Medicine^ p. 416 et seq. 44 AFRICAN HORSE DISEASE an understanding between them and the cattle whereby they are assisted and encouraged to destroy the ticks. Domestic fowls should be encouraged, and starlings and song- thrushes might be imported. To a stranger visit- ing the island (Jamaica) the scarcity of birds is a striking feature. I have been told that it is due to the mongoose, which has not only diminished the number of wild birds and domestic fowls, but other tick-destroying creatures such as the ground lizard. Now this destruction of the natural tick destroyers should, as far as possible, be prevented, firstly by legal protection, secondly by encouraging the slaughter of the mongoose." (For further remarks see Veterinary Journal, 1896.) African Horse Disease South African horse disease has no apparent con- nection with insects or surface wounds, but appears to depend, not upon conditions of the surface soil, but on temporary conditions of the vegetation which forms the pastures. South African horse disease (oedema mycosis) is described by Captain Hayes, F.E.C.V.S., in his trans- lation of Friedberger and Frohner's * Veterinary Patho- logy,' and is supposed by Edington to be caused by a mould (penicillium) which grows in the vessels, caus- ing thrombosis and exudation of serum, with fatal results. It appears to occur chiefly among animals which are allowed to graze while the dew is on the grass, and the growth of the microbe is supposed to be connected with the dampness of the grass. The disease, once contracted, is almost always fatal, but the prophylactic appears to be dry fodder and the folding of horses until the sun has dissipated the moisture of the dews. TRAMPS AND SMALL-POX 45 The history of those diseases which appear to depend on inoculations points with no uncertainty to the advisability of keeping a whole skin. The * verminous person ' has assumed an importance in relation to the public health which the Legislature has already recog- nised, while the ' tramp,' with his special liability to small-pox, is one to whom the anti-vaccinationist is likely to discover a * conscientious objection.' The special liability of the * tramp ' to suffer from small- pox—if such is really the case — seems to offer a field of investigation well worthy of being methodically explored. There are other diseases more or less suspected of being soil diseases, but the facts are at present too few to make any discussion profitable. These are yellow fever, beri-beri, swine fever (undoubtedly propagated by fouling of the surface soil), cancer (?), threadworms, hydatids, and ankylostomum duodenale. Malignant oedema is an infective disease of wounds undoubtedly caused by a ubiquitous anaerobic saprophyte, which occasionally manages to grow in the cellular tissue and to generate gas (COg, H, HgS, CH^) therein. 46 ENTERIC FEVER CHAPTEE VI ENTERIC FEVER Enteric fever has of late years much occupied the attention of epidemiologists and bacteriologists, and our knowledge of its definite relationship to filth, milk, and water has undergone considerable increase. The laboratory experiments connected with enteric fever are of great interest and value, but it would be, to say the least, hazardous to build upon them any measures intended for practical sanitation. It must never be forgotten that the typhoid bacillus does not fulfil one of Koch's postulates. The disease produced by the inoculation of guinea-pigs with pure cultivation of typhoid bacillus has but a remote resemblance to the disease which we clinically know as enteric fever, a disease which seems limited to the human species. Sidney Martin ^ found that *' none of the ordinary cultures of the typhoid bacillus obtainable in the laboratories will kill an animal,^ but that it may be rendered virulent by inoculation and transference through a succession of peritoneal cavities, and also by ' Croonian Lectures, 1898. ^ When therefore Sir Richard Thome in commenting upon Martin's pure cultivations of Bacillus typhosus in sterilised soil says that they yielded the bacillus ' presumably in virulent phase ' {Local Government Board Reports, 1897-98, p. 23), his presumption is scarcely warranted by the facts. SOIL 47 injecting simultaneously the products of other micro- organisms, such as streptococcus or Bacillus coli com- munis." It is noteworthy that the Bacillus coli com- munis and Gaertner's bacillus when subjected to similar manipulations are as toxic to rabbits as is the typhoid bacillus. It must be remembered that * pure cultiva- tions ' of the Bacillus typhosus cannot be said to exist in nature. We recognise, and it may be taken as proven, that the main cause of the endemicity and epidemicity of enteric fever in this country is to be found in the faeces of the patient, and yet Martin tells us that while the bacillus is invariably found in the spleen and mesenteric glands and in intestinal lesions, "it is found in some cases in the motions of typhoid fever and also in the urine." Dr. J. R. Carver, working under Delepine at Manchester, found the typhoid bacillus twice in twenty samples of typhoid faeces and once in sixteen samples of typhoid urine.* Osier records sixteen instances of bacilluria in fifty-one cases (1900-1901) and states that " bacilli may be present in the urine for years after the attack." Martin, working with sterilised soils, has shown that in soils which are more or less * polluted' with organic matter the Bacillus typhosus will continue to live and spread at ordinary temperatures, but that in virgin soils (both sandy and peaty) the pure cultiva- tions of the bacillus die out from some unexplained cause. Martin gives one experiment ^ to show that in unsterilised soil containing much organic matter the bacillus may continue to live, but as yet there has been no evidence of spreading. The results recorded in the same observer's more recent paper are that typhoid bacilli will grow and live for a long time in sterilised * Tlie- Lancet, August 20, 1898. ^ Local Government Bej^ort, 1897-98. 48 ENTERIC FEVER soils, but rapidly die out in unsterilised soils, being overpowered by the bacilli present in the soil. {See 27th (1897-98), 28th (1898-99), and 29th (1899-1900) Annual Eeports of the Medical Ofi&cer to the Local Government Board.) John Eobertson and Maitland Gibson ^ collected thirty samples of soil from areas which they considered likely to be infected. *' In not one single instance was the Bacillus typhosus found." These gentlemen carried out experiments in a field (soil, eight inches of clayey loam on ten inches of sand and clay on stiff yellow boulder clay) ; each experimental patch had the turf removed and nothing was allowed to grow upon it. The patches were eighteen inches square. Three patches were inoculated with 200 cubic centi- metres of a pure cultivation of the Bacillus typhosus mixed with one and a half gallon of tap water — No. 1 on the surface. No. 2 nine inches deep, and No. 3 eighteen inches deep, the top soil being removed and replaced. This was done on May 30, 1896, and on August 26 the Bacillus typhosus was found three inches below the surface of each, and at nine inches below the surface of No. 2 and No. 3, and also at eighteen inches below the surface of No. 3. On October 20 there were practically the same results. On November 27 the Bacillus typhosus could not be found in either patch. Towards the end of August, 1896, three other patches (Nos. 4, 5, and 6) were inoculated in the same way, and on November 27 no Bacillus typhosus could be found. These patches were three feet square. On January 17, 1897, patches No. 4, 5, and 6 received two gallons of very weak beef tea, which was repeated at fortnightly intervals till June 3, 1897, when on examination the organism was easily found. No organism was found at this date in patches Nos. 1, 2, and 3, which had not ' Brit, Med. Jour. January 8, 1898. EXPERIMENTAL 49 been fed with bouillon. Practically the same result was obtained on July 11. The persistence of the Bacillus typhosus appears to depend on feeding it with fluid nourishment. A sewer leaking into the soil would do this, or liquid filth in a privy. It was shown that the organism would grow three inches downwards or upwards from a depth of eighteen inches. The slight downward growth might be due to mechanical conditions. The effect of sunlight does not penetrate far. Laboratory experiments went to show that vegetation (grass) prevented the growth of the organism. This may go to explain * why typhoid fever is so much more prevalent in towns than in rural districts.' Attempts to prove the aerial conveyance of the organism from liquid filth failed. Further allusions by Dr. J. Kobertson to these experiments were made later in the year,^ in the course of which he said : '* During the winter months organisms disappeared from the surface soil, and from these experiments I was led to believe that the deeper layers acted as a sort of shelter during the winter months, from which the organisms sallied forth to the surface during the warmer months." He had not noticed any relation between typhoid fever and the rise and fall of the ground water, but he thought it was most common in places where the ground water is near the surface. The Bacillus typhosus quickly dies out in grass-covered areas. Let us now turn from these experiments, which, after all, are very artificial, to the practical experiences of sanitarians in the matter. It may be premised that Martin's experiments show that the Bacillus typhosus will grow in any soil rich in organic matter, and that although aerobic it can be cultivated as an anaerobe » Brit. Med. Jour. August 13, 1898. 50 ENTERIC FEVER even in an atmosphere of carbonic acid,^ and the bacillus seems to be definitely destroyed by sandy or peaty * virgin ' soils. Robertson and Gibson cultivated the bacillus on a soil in which clay predominated. Sir Charles Cameron is of opinion that it flourishes in gravel. At Dublin on August 23, 1898, he said, speak- ing of enteric fever : " That there is a connection between enteric fever and the soil is shown by the results of observations of the distribution of more than 4,000 cases of the disease in Dublin. Where gravel forms the site of streets there is far more typhoid fever than in districts which rest upon the stiff boulder clay. This is clearly owing to the fact that the Bacillus typhosus, which is aerobian — that is, requires oxygen — can get it more freely in the loose gravels than in the stiff clays. In the gravel, too, there is a much greater space for the development and movement of the bacilli." Dr. Scurfield, of Sunderland, said that ** the greater part of the county of Durham in which typhoid fever had been prevalent during the last few years was covered with stiff boulder clay, and in the urban district of Sunderland typhoid fever had been just as prevalent in the boulder clay as in the houses built on sand or gravel.' The late Professor Pettenkofer, of Munich, is mainly answerable for the theory that enteric fever is due to a soil organism which grows with maximum vigour when the level of the ground water falls. Dr. Christopher Childs, in a valuable paper which appeared in The Lancet,^ has placed us in possession of important facts. Munich lies on a bed of gravel 1,700 feet above sea-level. Between 1851 and 1896 the population had increased from 124,000 to 412,000, so ' Local Oovernment Board Report, 1867. 2 The Lancet, February 5 1898. MUNICH 51 that modern Munich is largely a new city. Up to 1865 Munich was a city of soak-away cesspools and filthy surface wells, and it was not till 1858 that the cesspool system began to be remedied, and not till 1865 that the water-supply began to be improved. Pettenkofer's early investigations, Dr. Childs says, led him to the conviction that in Munich there was not the slightest connection between the drinking-water and the typhoid,^ and this in spite of the fact that the water was shown on analysis to be organically polluted. The analyses and general investigations of the earlier date have been very imper- fectly recorded, but there is evidence, says Dr. Childs, that the water was much worse in the earlier periods than latterly. Of Pettenkofer's personal investigations Dr. Childs says : " I have not succeeded in finding recorded details, but they derive their weight from the high authority of Pettenkofer himself." The enteric death-rate, which (per 100,000) was 202*4 for the decade 1851-59, fell to 147*8 in 1860-69 ; to 116*7 in 1870-79. In 1880 it was 72 ; in 1881 it had fallen to 18 and has not risen since. The water in Munich is derived from the mountains, and when these are covered with snow the subsoil water falls. It is a most interesting fact to note that Petten- kofer's Munich typhoid fever was a disease of winter. The incidence of the Munich typhoid fever between the years 1851-67 was, according to Pettenkofer, in monthly averages as follows : February. . 36-8 April . 231 September . 161 January . . 33-5 November . 19-0 July . 15-8 March . . 31-8 May . 17-6 June . 15-2 December . 28-5 August . . 16-7 October . 150 > This may have been due to the fact that the wells were all equally bad. E 2 52 ENTERIC FEVER The average English sanitarian reading this account of Munich with its soak-away cesspools and foul drinking- water would not need any new theories to account for the prevalence of typhoid fever. If we accept Petten- kofer's theory that the fever was due to organisms in the subsoil, it is interesting to observe that the Munich fever, unlike typhoid fever in other places, reached its maximum in February, and was most rife in the coldest weather when the surface of the ground must have been often frozen. During the winter months, when the big houses were closed and the stoves were lighted, the interior of the houses must have been filled with cess- pool air. An organism permeating the soil might be expected to die out gradually. The sudden fall of the death-rate from 72 in 1880 to 18 in 1881 seems to imply that the organisms suddenly died over the whole area of the city. Munich is a city in which the general sanitary condition has undergone gradual amelioration. Sewers on modern lines were begun in 1878, and 800 private slaughter-houses were destroyed in the same year. There is now a highland water-supply and typhoid fever has gone. But it is needless to say that the sub- soil water rises and falls precisely as it did half a century ago. The connection of typhoid fever in Munich with organisms growing in the soil is to my mind not proven.^ In 1896 there were 111 cases of enteric fever at Chichester, of which the majority occurred in July and 1 Ziegler (in 10th ed., 1901, of his Allgemeine Pathologic, vol. i. p. 39) refers to Pettenkofer's view that the soil influences the virulence of the micro-organism by communicating a something to the latter under certain conditions, but adds that recent research on the etiology and spread of typhoid fever, cholera, and plague has not lent any support to such an hypothesis. CHICHESTER EPIDEMIC 53 August, and of which only two died (one committing suicide while delirious). Seventy- six houses were attacked in localities which had been repeatedly invaded in former years. Of these houses thirty-nine had well- water (quality doubtful), and thirty-six had company's water. In sixty-two of the cases the patients were males and in forty-nine they were females. There had been recent works of drainage, and it was found that the percentage of incidence of fever on the whole of the undrained houses of the town was slightly in excess of that of the drained houses. There was no evidence that the disturbance of the soil in this ancient walled city for works of drainage had inlfluenced the incidence of fever. Many of the houses attacked had old privies, &c., and the back yards were soaked with organic matter. Enteric fever, as usual, showed a preference for filthy surroundings. This outbreak has been spoken of as due to the growth of the Bacillus typhosus in the soil round the houses attacked, but the evidence is certainly not conclusive, and the fact that the women who mind the house suffered less than the men is rather opposed to such a theory. The epidemic, which departs somewhat from ordinary epidemics in the time of its maximum virulence and its very low mortality, remains un- accounted for. Chichester is built on a bed of gravel. (The facts as to this epidemic are culled from Dr. Bul- strode's report to the Local Government Board.) In 1898, seventy-six houses in Chichester were again in- fected with enteric fever. Of these fifty-eight were * drained ' and eighteen * not drained ' ; forty-four con- sumed town water, while thirty-two had well-water. Mr. Jones, the medical officer of health, points out that the percentage of incidence was markedly in excess 54 ENTERIC FEVER in the ' well-water ' houses and slightly in excess in the * undrained ' houses. Enteric fever has long been regarded as a filth disease, and there is abundant evidence that filthy sur- roundings in some way or other predispose to it. Waterlogged privies soil-sodden with the leakage of sewers, the air of cesspools and traps, proximity of water-closets to the kitchen, and other conditions of filth are all bad. While we agree as to the fact we may differ as to the explanation. Some would assert that the Bacillus typhosus is actually growing and spreading in the filth, and indeed that is possible, but direct evi- dence of it is wanting. Some would even say that the soil being inoculated the specific organism may con- tinue to grow and spread in it far away from the point of inoculation, and so (by growth, not irruption) may poison the local water at a distance. Of this there is positively no evidence whatever. If for the sake of argument we allow that the Bacillus typhosus may grow in the soil we have to ask how it emerges from the soil to do us harm. We are here confronted with con- tradictions. Eobertson and Gibson showed that the bacillus disappeared in the winter to reappear in the summer, while at Munich the increase of enteric fever was a phenomenon of midwinter. In Budapest it is associated with a rising ground-water, and at Munich with the opposite condition. In this country it is a disease of autumn and the period of floods, while others assert that it may be conveyed by dust, which ought to produce a prevalence in March. The opinions held by sanitarians and bacteriologists on this question differ widely, but there seems to be a consensus of opinion that a waterlogged soil rich in organic matter is the one in which the Bacillus typhosus is most likely to FLIES 55 flourish. If this should be true the official position that in sewage treatment filtration through earth is a sine qua non becomes untenable. In the discussion which followed a paper which I had the honour of reading before the Eoyal Medical and Chirurgical Society in November, 1898, on the Preven- tion of Enteric Fever, and which has been published in vol. Ixxxi. of the Transactions of that Society,^ many eminent sanitarians and bacteriologists made most valu- able statements. Sir Kichard Thorne said, p. ^Q: "I do not think Nature made any provision for the disposal of specific excreta. Nature provides an easy means of dealing with the ordinary healthy excreta of healthy people living on the land, but dangers arising from specifically contaminated excreta are, I fear, much more difficult to be thus got rid of." ^ The danger from flies is, in Director -General Jame- son's opinion, a very real one in tropical countries. By their agency faecal poisons are probably carried to the food or milk. Dr. Sims Woodhead said : " We stand in need of further information in respect of the continu- ance of the typhoid bacillus in soil. I agree . . . that the typhoid bacillus has a much greater chance of per- sistence in a waterlogged soil containing a moderate amount of organic matter than in a dry, well-aerated soil, however large an amount of organic matter it may contain. In this, however, my actual experience is limited, though I hold a strong opinion on the sub- ject." When we consider that the bacillus of typhoid fever may remain in the intestine for some time after ' This paper will be found on p. 135 of this volume. 2 This opinion is not quite in harmony with Sidney Martin's repeated demonstrations that the Bacillus typhosus is killed by virgin sand or peat, and the death of it in Eobertson and Gibson's soil which had not been watered with beef tea, and its extermination by growing grass. 56 ENTERIC FEVER recovery as well as in the urine and gall-bladder, and when we also remember what Metchnikoff pointed out in relation to cholera, viz. that the vibrio may be present in the intestine a long time before an attack of cholera occurs, it would seem that we can have typhoid bacilli under very similar conditions present in the intestine in practically healthy individuals, and that this bacillus may remain in the intestine a considerable time before the intestinal tract becomes so altered that the bacillus has a chance of doing its special work. Then it is that bad, though not actually infected water, may help the typhoid bacillus to do its work. Dr. Corfield insisted on the importance of sewer air and cesspool air as factors in producing the endemicity of enteric fever. He instances Lyons as a city in which cholera has never spread, but in which typhoid fever is endemic. Lyons is a city of cesspools. Loesener, in a paper ^ on the * Viability of Pathogenic Bacteria in Interred Corpses,' states that he injected into the vessels and cavities of dead pigs a great quantity of pathogenic bacteria so that their number should exceed that of the saprophytes. In the first experiments the animals were not interred, and under these conditions the viability of the bacilli of typhoid fever and cholera did not exceed four or five days. When the animals were treated in this way and buried in a porous soil the pathogenic bacteria manifested a maximum viability as follows : Typhoid fever (one instance only) ninety- six days, cholera twenty-eight days, tubercle ninety -five days. Bacillus pyocyaneus thirty-three days, pneumo-bacillus of Friedlander twenty-eight days. Micrococcus tetragonus twenty-eight days, and tetanus 361 days (showed com- ' Arbeiten aus dem kaiserlichen Oeswidheitsamte, vol. xii. f. 11, p. 448. CEMETERIES 57 plete virulence after 234 days). The Bacillus anthracis preserved its complete virulence during the whole year of the experiment, and the bacillus of rouget du pore ^ and septicaemia of mice 234 days. As for the typhoid bacillus, it was possible to isolate it from the buried corpses only once. * I believe,' he says, * with Koch that the value of Pfeiffer's reaction of immunity is relative, and that outside the human body it is not in our power to identify the typhoid bacillus.' Lcesener's conclusion is that cemeteries are not harmful (even when graves made in a permeable soil are liable to inundation either temporarily or perma- nently) provided the graves be surrounded by a layer of earth sufficient to filter the liquids traversing them.^ ' Kobin, in Nouveau Diet. Abr4gi de Medecine, dc. 1886, states that rouget du pore is, according to some observers, anthrax in the pig, to others typhoid fever of pig (Pasteur). In Hayes's translation (1898) of Friedberger and Frohner's Veterinary Pathology, vol. i. p. 75, swine erysipelas is given as the equivalent of rouget du pore. 2 From Annales d'Hygi^ne Puhlique et de Medecine Legale, troi- si^me s6rie, tome xxxvii Janvier 1897. 58 MAIDSTONE EPIDEMIC CHAPTER VII TRE MAIDSTONE EPIDEMIC The epidemic of enteric fever in Maidstone in 1897 is of great importance in relation to the influence of the earth on contagion, and the report to the Local Govern- ment Board by Mr. J. S. Davy, Dr. T. Thomson, and Mr. G. W. Willcocks has put us in possession of most of the essential facts. The date of the attacks (the notifications were later) in the town and in the County Lunatic Asylum as given in Table I. of the report were as under : Table I. Week Ending Borough Asylum September 4, 1897 . 29 11 „ 165 1 18 „ 434 18 25 „ 432 48 October 2 „ 274 12 » 9 » 134 15 16 „ 64 4 23 „ 45 2 30 „ 33 4 November 6 „ 25 2 13 „ 23 1 20 „ 19 — 27 „ 13 — December 4 „ 4 — 11 » . 5 — 18 „ . 3 — 25 „ 2 January 1, 1898 . 3 — FARLEIGH SPRINGS 59 It was conclusively shown that the outbreak was due to the pollution of a spring or springs belonging to the Farleigh water-system. Of persons drinking this water nearly 8 per cent, were attacked, while of those drinking water belonging to other systems of supply less than 1 per cent, were attacked. The Farleigh springs, which are fifteen or sixteen in number, crop out on both banks of the Medway (mainly on the left bank) where the overlying and permeable green sand (locally known as * ragstone ') rests upon the impermeable clay beneath. The water of these springs is for the most part pumped to the Barming reservoir, whence it is distributed mainly to the higher parts of the town. The Farleigh springs yield collectively over 3,000,000 gallons a week, and they were treated collectively, and their waters were all mixed in one reservoir, holding 500,000 gallons, before distri- bution. That this reservoir and the pipes connected with it became polluted with enteric poison was beyond doubt, but it was not quite so clear which of the con- tributing springs was at fault. When, however, the springs were examined on September 19, one and one only was found to be dirty, viz. the spring known as * Tutsham-in-Field.' In order to condemn this spring, which yielded only 35,000 gallons per week, both chemical and bacteriological analyses were wholly superfluous, and accordingly it was cut off from the supply on the following morning, September 20. This spring was reported as still dirty a month later, and when I saw it on November 5 it was still turbid, and manifestly unfit for drinking purposes. * Kagstone ' is often fissured, and there had been experiences in the Borough of Maidstone of the pollution of an old municipal supply known as ' the Conduit,' and of a well known as * Hill's Well,' by leakage of sewage 6o MAIDSTONE EPIDEMIC from broken pipes and similar well-understood causes. Bacteriological investigations were made by Dr. Wash- bourn and Dr. Durham on behalf of the corporation, by Dr. Sims Woodhead and Dr. Cartwright Wood on behalf of the water company, and by Dr. Tew and Mr. Foulerton on behalf of the rural authority. The first four were all agreed that Tutsham-in-Field water afforded evidence of animal pollution on September 19 and 20, and the last two found similar evidence in the mixed Farleigh waters taken at Barming on September 22. It is noteworthy, and of very great importance, that diligent search was made for the Bacillus typhosus by the six eminent bacteriologists engaged, but without success. The situa- tion of the Farleigh springs was such as to render them liable to pollution, and on chemical grounds they were open to suspicion, but only one of them (Tutsham-in- Field) was really convicted of animal contamination and was obviously dirty and unfit to drink. The facts of the epidemic are, I think, quite consistent with the theory that it was caused by pollution of the spring at Tutsham- in-Field. The Tutsham-in-Field spring derived its immediate supply from the under draining of a hop garden, and a reference to the diagram will show that its natural flow was assisted by some 20 feet of earthenware pipes, with open joints, which lay immediately on the Atherfield clay, and at a depth below the surface which varied from 2 feet near the catch-pit to 4 feet at the end which was farthest in the hop garden {see fig. 1). Immediately above the spot where the open pipes are nearest to the surface was a fence made of stakes driven into the ground, which may have served as direct conducting channels down to the open-jointed pipes. (Parentheti- cally, I would remark that the danger of a dead fence in TUTSHAM-IN-FIELD 6i such a connection ia much greater than a hedge with living roots.) Close to this fence were deposits of faeces. The line of the spring occupies a slight depression in the JL_V TUTSHAM 'N FIELD Fig. 1. ground, and the natural surface drainage must have been to a spot very close to that at which the collecting pipes were shallowest. This spot was only a few yards from a path which crosses the hop-garden fence by means of a stile, and in short the circumstances were TUTSHAM "N FlCLD Fm. 2. such that the risk of befoulment of the ground close to the collection pipes was very great ^ {see fig. 2). If the diagrams at Tutsham- in-Field be compared ' In his report to the Local Government Board Mr. P. Adams speaks of this fence as a 'hedge,' but both the photograph and the plan show that it was a ' fence.' The point is not unimportant when the tendency of fences to rot at the foot is considered. 62 MAIDSTONE EPIDEMIC with those of Tutsham -in- Orchard and Ewell (figs. 3 and 4) it will be observed that earthenware pipes with open joints are used in all of them, but while in the I a 3 4 8 "^Stoitii TUTSHAM 'N ORCHARD Fig. 3. first-named these open joints came to within 2 feet of the surface, they did not come nearer than 5 feet at Tutsham-in-Orchard and 14 feet at Ewell. The surface Fig. 4. of the ground above the pipes was formed of turf at Tutsham-in-Orchard and Ewell. The Tutsham-in- Orchard spring was bright and apparently wholesome, RAINFALL 63 and the Ewell spring appeared to be the purest water of the whole of the Farleigh group. It must be remembered that the 3 feet of hop ground which covered the open-jointed pipes at Tutsham- in-Field was of a sticky, clayey nature, liable to crack and fissure in times of drought, and there can be little doubt but that the rain which washed this spot ran with its washings almost direct to the reservoirs. Under the circumstances which existed it is very important to study the rainfall and the exact times of its incidence. It is obvious that without rain no infective material could be washed into the * spring,' and it is also obvious that a short sharp shower might do infinite mischief at Tutsham- in-Field and yet be insufficient to affect the level of the subsoil water in Maidstone. Let us look at the facts of the epidemic from this point of view. The incubative period of enteric fever is stated by the Clinical Society of London to vary between five and twenty-three days. I am justified, therefore, in assum- ing that the majority of those who might receive a dose of poison to-day would be attacked between the seventh and twenty-first day following. Between June 28 and August 7 there had fallen only 0*21 inch of rain. At the end of a dry period the delay in the distribution of water would not be great, but it is obvious that a house cistern might be charged with infective material, and considerable delay might occur before the attacks, if the bulk of the household were away. After forty days of drought rain fell to the extent of 0*44 inch on August 7 and 8, and 0-13 inch fell on August 15. On August 17 and 18 there was a fall of 0*53 inch, and if this rain washed infective material to the reservoir it should cause attacks between August 24 and September 9. The first attack of the epidemic is stated to have occurred on 64 MAIDSTONE EPIDEMIC August 28, and between that and September 8 there were 101 attacks. On August 26 hop-picking commenced, and the population round the Tutsham spring was neces- sarily increased. On that day there fell 0*35 inch of rain, the heaviest fall in any one day since May 80. The effect of this shower should become manifest between September 2 and September 16. The attacks down to August 8 have been previously given, but between the 8th and 16th there were 385 attacks. On September 1 there was 0-31 inch of rain ; again on September 5, in the very middle of the hop-picking, there fell 0*44 inch, the heaviest fall since March 2. The effect of this should become manifest between September 12 and 26. Omitting the cases down to and including the 16th, we find that between the 17th and 26th inclusive there were 625 attacks. There was 0*27 inch on September 8, hop-picking being still in progress. This would carry us on to September 27, 28, and 29, in which days there were 122 cases. On September 18 and 19 (hop-picking having come to an end on the 13th) there fell 0*51 inch. This would take us down to October 9, and we find that from September 30 to October 9 there were 237 attacks. On September 20 the Tutsham springs were cut off, the effect of which would not be fully manifest for three weeks. On October 12 the daily attacks suddenly dropped from eighteen to seven. It must be borne in mind that the Tutsham spring had presumably sent a considerable dose of muddy water to the Barming reservoir on September 18 and 19, the very day before it was cut off, when there fell 0*51 inch of rain, and the influence of this would be felt up to October 11 at least. On October 11 and 12 the daily attacks fell from eighteen to seven and never rose again above nine. We must remember that after TUTSHAMJN-FIELD 65 the Tutsham springs had been cut off there was the possibility of poison lurking in the foul Barming reser- voir, the water pipes, and the house cisterns. On Sep- tember 29 there fell 0-83 inch of rain, a shower of tropical severity, and it is exceedingly likely that in the stirring up of the town sewers there may have been some leakage into the water service. There is no evi- dence on the point, but such things do happen ai; such times. In any case the effect of the wholesale poison- ing of part of the water system which had taken place would be likely to endure for some time. It was not till October 18 that the implicated water system was in great part (but not wholly) disinfected, and this process was not completed entirely until November 4. The full benefit of this would show itself three weeks later (November 25). In the weekly returns of attacks (see Table I.) there were only four for the week ending December 4, as against thirteen for the week ending November 27. Subsequent to November 27 there were only seventeen attacks. The epidemiological facts of this outbreak are quite compatible with the theory that the dirty water sup- plied from Tutsham-in-Field was the main cause of the outbreak, and I do not think that the effects of the contamination could be expected finally to disappear until three weeks after the completion of the disinfec- tion of the water service on November 4. The inspectors in their report fix October 18 as the day when the influence of the Farleigh water ceased to be felt in Maidstone, and they say (p. 32) : ** Nearly all the cases notified after October 18 (some 280 in number) are to be regarded as having had a cause other than the consumption of Farleigh water." This opinion seems to imply that in the estimation of the inspectors the dis- 66 MAIDSTONE EPIDEMIC infection of the Farleigh water system which began on October 16 and continued until November 4 was super- fluous and useless. Speaking of the 280 cases they continue : *' By Mr. M. A. Adams they were referred to direct infection from previous cases and to insanitary conditions of water- closets, drains, and sewers. This explanation appears to us to be the probable one if the insanitary conditions referred to be taken in the wide sense of including the fouling of the soil by leakage from these defective drains and sewers. Kecent researches into the life-history of the bacillus of typhoid fever go to show that this organ- ism finds in a soil contaminated with foul matters from leaky sewers, drains, and cesspools conditions especially favourable to its vitality and multiplication. That the soil on which Maidstone stands is thus contaminated was set beyond doubt by the evidence put before us. To the existence of these conditions is mainly, we con- sider, to be attributed the remarkable persistence of fever in Maidstone after the primary cause of the out- break had been removed by cutting off the Farleigh water-supply." Do the facts of the case really establish the con- clusion which the inspectors say is ' set beyond doubt ' ? I do not find a single word in the report or a single experiment to prove that the Bacillus typhosus was growing in the soil of Maidstone. The epidemic is re- markable not only for its severity but from the fact that six gentlemen, all eminent for their skill in bacteri- ology, failed to discover a single typhoid bacillus. The bacteriological investigations were upon a scale which was quite unprecedented and in so far as the Bacillus typhosus was concerned were entirely and absolutely negative. It may be, as the inspectors PRISON AND BARRACKS 67 hint was the case, that the Bacillus typhosus was permeating the soil of Maidstone in November, De- cember, and January very much as a blue mould permeates a cheese, but no examination of the soil is recorded in the report. There are facts, however, which make strongly against any such contention. These were the total escape of the barracks and prison. On page 26 of the report is the following paragraph : " The barracks and the Maidstone prison are both within the borough and both are connected with the town sewers. The population of the barracks was 300, this total including 166 men, 44 women, and 88 children. The water supplied to the barracks is that of the Boarley system of the water company's supply. No case of typhoid fever occurred in the barracks during the year. At the prison the average population through- out the year was 171, the total number of prisoners received being 1,925. The water used on weekdays is from a well 34 feet deep sunk in the Hythe beds of the lower greensand. On Sundays water is turned on to the prison from the Boarley mains. There have been no cases of typhoid fever or diarrhoea among the prisoners or staff during the whole of 1897." During the five months (August to December) there were probably 800 persons who drank water from the 34-feet well sunk in the ' contaminated ' soil of Maidstone. A reference to the map (fig. 5) will show that the area of the prison is closely hemmed in on the north and east by fever- stricken houses, and the escape of the prison and barrack populations is most remarkable. Neither rise nor fall of subsoil water brought tj^phoid fever or diarrhoea to the prison. The investigations connected with the Maidstone epi- demic are of great interest as pointing to the wonderful F 2 68 MAIDSTONE EPIDEMIC protection which the humus affords to the underlying water against pollution from above. The whole of the Farleigh springs were of the same character, the catch- pits of many of them w'ere liable to invasion in time of flood, and the gathering-ground of most of them was highly cultivated and manured land. And yet none of them (always excepting Tutsham-in-Field) afforded Fig. 6. ' Spot ' plan of surroundings of Maidstone barracks and prison. The big numerals sliow the height above sea-level. The black dots are fever-stricken houses. evidence of serious bacterial impurities. It may be added that in the third quarter of 1898 there was one death from enteric fever in Maidstone and another death from the same cause in the fourth quarter, so that the * con- taminated ' soil of Maidstone was not able to contami- nate the inhabitants during the drought of July, August, and September or the rains of October, November, and December of 1898. IMMUNITY 69 CHAPTEK VIII IMMUNITY— DANGER OF WOUNDS Bacteriologists have abundantly proved that the germs of disease are ubiquitous. They are found in earth, air, water ; in the dust and on the walls of our dwellings ; in clothing, in meat, milk, bread, and even occasionally, as Andrewes has shown, in hot baked rice-pudding. With regard to most of the necessities of life we hear the cry of * unclean,' * unclean,' until the wonder is that we are any of us left alive to warn our neighbours. The fact that many of us manage to live to a respectable age and to die from something which is non-infective cannot but make us consider whether, after all, the immunity of the individual is not the fact which tends more than any other to the improvement of the public health. It is wholesome for us to remember that the greatest sanitary achievement of our time has been the practical disappearance of typhus fever. Of the causa causans of this disease we know nothing. Its absolute disappearance has not been produced by successful germ hunting. Its disappearance is probably due to the im- proved conditions under which the masses of the popu- lation live as regards food and cleanliness. Few of us doubt that if this country should become involved in war, and food should become dear and scarce in conse- quence, the relative immunity of the population would yo IMMUNITY be lessened and typhus fever would re-assert its sway. Whether we succumb to an infective disease or not probably depends in great measure upon the dose of the poison which we receive. When an endemic disease such as enteric fever becomes epidemic it is due to the sudden dissemination of a poison in relatively large or virulent doses. Even in the most severe epidemics it is rare for more than 10 per cent, of those who have run obvious risks of receiving the poison to be attacked. The questions of virulence and vulnerability are most important. It seems to be well established that the virulence of some of the pathogenic microbes varies immensely with the conditions of soil, temperature, air, sunlight, &c., under which they are grown, and it is a fact that must be remembered that it is not always the pure cultivation which manifests most virulence. Many infective diseases assume a virulence in the tropics which is rarely met with in temperate countries. This appears to be true of tropical malaria, enteric fever, cholera, yellow fever, anthrax, and tetanus. In hot countries where a temperature equal to the optimum for the growth of many pathogenic microbes is often continu- ously maintained for weeks in succession, the risks of contagion and the danger of uncleanliness must often have become apparent in a manner more convincing than is the case among us. The repeated injunctions as to uncleanliness in the Mosaic law, and the rigid rules laid down as to the conditions which made a man unclean and which necessitated his subsequent purifica- tion, must have been the outcome of experience. To eat with unwashed hands in a tropical country and without knives and forks would clearly be to run considerable risks. The regulations in force among the Hindus were even more stringent, and although some of the regula- HINDU MANNERS 71 tions may appear to us to be extravagant and nonsensi- cal, it is impossible not to admit that most of them have for their aim the protection of the individual and his fellow man from the risks of infection.^ • In the Abbe Dubois's book on Hindu Manners, Customs, and Ceremonies, translated by Beauchamp (Clarendon Press, 1897), will be found a chapter (vol. i. p. 238), largely culled from the great book of Brahmin ritual called Nittia-Earma, on hygienic rules, and among them a section on ' Eules to be observed by Brahmins when answering the Calls of Nature.' 1. Taking in his hand a big c7iem&t^ (brass vessel) he will proceed to the place set apart for this purpose, which should be at least a bowshot from his domicile. 2. Arrived at the place he will begin by taking off his slippers, which he deposits some distance away, and will then choose a clean spot on level ground. 3. The places to be avoided for such a purpose are the enclosure of a temple, the edge of a river, pond, or well, a public thoroughfare or a place frequented by the public, a light-coloured soil, a ploughed field, and any spot close to a banyan or any other sacred tree. 4. A Brahmin must not at the time wear a new or newly-washed cloth. 5. He will take care to hang his triple cord over his left ear and to cover his head with his loincloth. 6. He will stoop down as low as possible. It would be a great offence to relieve oneself standing upright or only half stooping ; it would be a still greater offence to do so sitting upon the branch of a tree or upon a wall. 7. While in this posture he should take care to avoid the great offence of looking at the sun or the moon, the stars, fire, a Brahmin, a temple, an image, or one of the sacred trees. 8. He will keep perfect silence. 9. He must chew nothing, having nothing in his mouth, and hold nothing on his head. 10. He must do what he has to do as quickly as possible, and rise immediately. 11. After rising he will commit a great offence if he looks behind his heels. 12. If he neglects none of these precautions his act will be a virtuous one, and not without merit ; but if he neglects any of them the offence will not go without punishment. 13. He will wash his feet and hands on the very spot with the water contained in the chembu which he brought. Then taking the vessel in his right hand and holding his private parts in his left, he will go to the stream to purify himself from the great defilement which he has contracted. 14. Arrived at the edge of the river or pond where he purposes to wash himself he will first choose a suitable spot and will then provide himself with some earth to be used along with the water in cleansing himself. 15. He must be careful to provide himself with the proper kind of earth and must remember that there are several kindg 72 IMMUNITY There can be no doubt that the health and vigour of the individual are all-important in relation to infective disease. The enervating influence of a tropical climate upon Europeans is recognised as a potent predisposing cause of infective disease, and if to the effects of climate be added those of inordinate fatigue and insufficient which cannot be used without committing an offence under these cir- cumstances. Such are the earth of white ant nests, potter's earth, road dust, bleaching earth, earth taken from under trees, from temple enclo- sures, from cemeteries, from cattle pastures, earth that is almost white like ashes, earth thrown up from rat-holes, and such like. 16. Provided with the proper kind of earth he will approach the water, but will not go into it. He will take some in his dtemhu. He will then go a little distance away and wash his feet and hands again. If he has not a brass vessel he will dig a little hole in the ground with his hands near the river side and will fill it with water which he will use in the same way, taking great care that this water shall not leak back into the river. 17. Taking a handful of earth in his left hand he will pour water upon it and rub it well on the dirty part of his body. He will repeat the operation, using only half the amount of earth, and so on three times more, the amount of earth being lessened each time. 18. After cleansing himself he will wash each of his hands five times with earth and water, beginning with the left hand. 19. He will wash his private parts once with water and potter's earth mixed. 20. The same performance for his two feet, repeated five times for each foot, beginning, under the penalty of eternal damnation, with the right foot. 21. Having thus scoured the different parts of his body with earth and water he will wash them a second time in water only. 22. After that he will wash his face and rinse his mouth out eight times. When he is doing this last act he must take very great care to spit out the water on his left side, for if by carelessness or otherwise he unfortunately spits it out on the other side he will assuredly go to hell. 23. He will think three times on Vishnu and will swallow a little water three times in doing so. In the course of some remarks on Ankylostoma duodenale in dogs, Mr. Arthur Powell (late of Kalain, Cachar, and now of Bombay) {Brit. Med. Journ. vol. i. 1900, p. 1,452) says : " It is a fact, not generally known outside India, that a Hindu considers it a grave insult to address anyone without washing the mouth after defacation. Anyone who has travelled on the rivers of Assam is familiar with the sight of the banks in the early morning. Every riparian native defsecates at the water's edge, completes the * toilet of the perineum ' in the river, and then ENTERIC FEVER 73 food, the risks of infection getting a hold of the organ- ism are greatly increased. Director-General Jameson told us in the debate on enteric fever already alluded to that "in almost all the posts occupied by European troops co-operating with the various columns in Afghanistan, extending from the British territory up to Kabul and Kandahar, cases of enteric fever appeared, some of which posts were occupied probably for the first time since the world began." In the Nile expedi- tion in 1889 those troops suffered most which had undergone most exposure and fatigue, " and it becomes difficult to resist evidence tending to show that in the causation of this disease there may be more factors than are generally acknowledged." Dr. Maclean, R.N. (in a letter to Sir J. Fayrer), alludes to the occurrence of enteric fever in the Island of Ascension, under circum- stances of close observation where no connection could be traced with defective sanitary arrangements, though it is probable that malarial influences did occur. " There is no such thing as a drain or a cesspool in the island, all the sewage and other filth being removed daily and thrown into the sea to leeward of all dwelling-houses. The water, partly collected from the roofs of buildings rinses out his mouth from the same water, though he sees the whole bank studded with his fellows engaged in one or other stage of this operation." Mr. Charles Bentley, M.B., CM. {Brit. Med. Joum. January 25, 1902, p. 190), contends that 'ground itch,' a skin disease of the feet affecting coolies working in the tea gardens of Assam during the wet season, is caused by the larvae of the Ankylostoma duodenale, which are hatched out from the fseces deposited at random by the coolies near their ' lines.' Mr. Bentley's experiments appear to bear out his contention. The larvae are killed by desiccation, so that they disappear in the dry season. [The deposition of faeces at random is indefensible. They should be deposited methodically on a well- tilled humus, which should be planted forthwith.— G.V.P.l 74 IMMUNITY during rain and partly condensed, is stored in iron and cemented stone tanks and removed from all possible sources of contamination." It is of course possible that in a case such as this the Bacillus typhosus may be lying dormant in the body ready to assert itself when bodily enfeeblement reaches a certain pitch. It has been asserted (and the assertion received the support of the late Professor Kanthack) that the Bacillus typhosus may be found in an abscess years after the attack, and the same thing holds good in a less degree with regard to the microbes of diphtheria and cholera. Nothing is better established with regard to tubercle than its relation to overcrowding and unwholesome occupations. Three times as much tuberculous disease occurs in the centre of London as at the outskirts, and an hotel servant in London runs a risk of dying from tubercle nearly ten times as great as that of the farm labourer. In our combat with this disease we must by no means confine our efforts to microbe hunting. So again with * filth diseases,' we must remember that almost all infective diseases are especially fatal to those who live in the midst of filthy surroundings. It is not, I think, at all necessary to assume, although it is possibly the case, that specific organisms are growing in the filth. In the cramped dwelling of the artisan, where the privy is often barely six feet from the back door, the risks of faecal befoulment of the food or person are very great, and when in such places large pails of faeces are left to putrefy for a week or more, it is not to be wondered at that the inhabitants should show an undue predisposition to the infection of enteric fever, as has been pointed out by Boobbyer and others. But it must be remembered that wherever putrefaction is going on and wherever anaerobic organisms are grow- ODOURS 75 ing in a filth-sodden soil unwholesome gases, such as CO2, H2S, CH4, and H, are being given off, and it is impossible not to admit that the breathing of these gases from week end to week end in the crowded courts of a great city may so lower the vitality of the body as to increase its vulnerability to infection of all kinds. But these gases which are naturally given off from sewers and sewer traps, from cesspools, from privies and from waterlogged and filth-sodden soil are accom- panied by ' odours ' which are often too subtle for the chemist to analyse but which, nevertheless, are suffi- ciently potent to make a strong man sick and faint and to reassert themselves in the excreta twenty-four hours after being inhaled. The odour given off by a tropical arum at Kew some few years since during the time it was in flower and just ripe for fertilisation was of a kind which could only be described as appalling and which made it impossible to enter the house where it was growing without putting a clip on the nose and holding the breath. I merely want to emphasise the fact that odours may have a power which neither the chemist nor the bacteriologist can gauge, and that we must be ready to admit that to live in stinks and filth must depress the health and increase the susceptibility to infection by microbes some of which have perhaps a greater measure of ubiquity than we are definitely aware of. Professor Stewart Stockman ^ reports an investiga- tion which he carried out on a septic organism which proved fatal to 380 fowls out of 400 on a poultry farm. He says : " The most important thing about this bacillus seems to me to be its fatal effect on tuberculous birds while it appears to be non-pathogenic, or nearly so, * Yeterinarian^ September, 1898. 76 IMMUNITY for healthy birds. It is also interesting to note that it killed a rabbit affected with the coccidium oviforme although the healthy ones were little affected by it. This observation, I think, affords fresh evidence in favour of what is taught about certain other microbes — namely, that they are only pathogenic to the enfeebled organism." It is an established fact and is now universally accepted that infective organisms may gain access to the body through the smallest conceivable wound whether of the skin or the mucous membrane. The various forms of septicaemia as well as erysipelas and malignant oedema are due to this cause. Tetanus, as we have seen, is always due to the inoculation of a wound, and it is a question whether anthrax of cattle is not more often caused by inoculation of a skin abrasion than hitherto has been suspected. Whether any of our common infective fevers are communicable by accidental inoculation is a moot point and one which is certain to receive a full share of attention in the immediate future. It is certain that in the transmission of plague a broken skin bears a most important part, and it may be that other infections may be conveyed in the same way. A distinguished pathologist is credited with having in- fected himself with enteric fever by a post-mortem wound. The infections brought about by flies, ticks, and mosquitoes are at present attracting much attention from pathologists, and it seems probable that the danger of certain ' soils ' and climates may be shown to be due in an increasing degree to the insects which find in the localities the various conditions necessary for their existence. It may be that in some instances an abrasion of the skin made by an insect may merely serve as a point of entrance for infective organisms abounding FLIES 77 in the surface of the soil or in the immediate surround- ings of the individual and having no necessary con- nection with the insect itself. It seems certain, however, that in the majority of instances which have been worked out a particular species of insect serves as an intermediary host for a specific organism which affects a specific animal. We hear a good deal in a loose and speculative way about flies conveying fever. This may be true, but we must always bear in mind what I feel inclined to call the excessive specialism of nature. Insects which feed on dung and carrion are seldom attracted by the food of human beings, and I confess to being somewhat sceptical as to the accidental conveyance of infection by * flies ' which heedlessly buzz first into the faeces and then into the milk. The pathologist of the future will clearly have to call in the help of the entomologist. 78 PRACTICAL CONSIDERATIONS CHAPTEK IX PRACTICAL CONSIDERATIONS The Maidstone epidemic has been very useful in directing attention to some of the common conditions which endanger water-supplies. Pasteur and all sub- sequent bacteriologists have directed attention to the value of the earth as a filter, and it is a matter of common knowledge that a very shallow layer of compact earth will remove the bacteria and much of the organic matter from water percolating through it. The greatest danger to shallow wells is to be found in subterranean collections of filthy fluids which leak through fissures in the earth, and with a gradually increasing hydraulic pressure. If there be no such dangers in the immediate neighbourhood, then a properly constructed shallow well is safe. The lined well five feet deep which I have in the middle of my garden has given water of exceptional purity for years, notwithstanding that the ground is cultivated with human excreta to within six or seven feet of the well. Dr. Macmartin Cameron, medical ofiicer of health for Kirkcudbright and Wigtown,^ shares my opinion that a * surface well ' properly constructed and in a selected situation is a safe source for water. Dr. Cameron's paper embodies much experience obtained in his official ' Brit. Med. Jour. August 13, 1898. SHALLOW WELLS 79 capacity, and many of his observations are worthy of quotation as showing some of the limits of danger and safety in relation to shallow wells. " The construction of new village wells. — When the wells of a village are shown to be contaminated, and a new water supply becomes imperative, it is not, as a rule, necessary — not, at least, in the province of Galloway, for which I have the honour to be medical officer of health— to press on a gravitation scheme as the only way of meeting the difficulty. A simple and inexpe -sive well scheme will often suffice. All that is requisite is to sink new wells outside the precincts of the village on higher ground if practicable. Commonly enough, the selfsame water that feeds the old wells may be tapped at a point before it has entered the polluted ground of the village. All that is then required to secure perpetual immunity from pollution is to obtain possession of a sufficiency of ground around each well to be devoted for all time to purposes of filtration. With a sufficient reserve (anything, say, from half to one acre, according to circumstances) little or no danger will accrue from ordinary agricultural operations beyond, but it would be better that as much as possible of the outlying ground should be left under grass. There is no safer or better water than that which a surface well in an old grass park can be got to yield. This is an ideal site. I should have no fear even of a top dressing of manure, provided the ground in the immediate vicinity of the well were not profaned. " Professor Hunter Stewart (Edinburgh) remarked that Dr. Vivian Poore's experiment with a six-feet well carefully cemented at the sides gave water which contained seven micro-organisms to the cubic centi- 8o PRACTICAL CONSIDERATIONS metre and the Bacillus coli was conspicuous by its absence. A part of the supply of the city (Edinburgh) was from wells near the Pentland Hills, not more than eight feet deep, situated in highly manured land, and exposed to pollution from neighbouring middens. From the water of these particular wells of a maximum of eight feet in depth, he found a maximum of micro- organisms of eleven to the cubic centimetre, and a minimum in three out of eight wells of absolute sterility. These observations abundantly supported the observa- tions of Dr. Poore." ^ Keverting to the conditions which obtained at Maidstone, I will mention a few considerations which, though obvious enough, are often neglected. During a drought, such as occurred in June, July, and August, not only would the stiff hop land be liable to crack, but the earthworms would retire to the lowest point in search of moisture. At such times they go deeper and deeper into the soil, and lie coiled up in oval knots at the bottom of their burrows. I have upon the table a piece of a worm -burrow removed from my garden in September last at a depth of more than two feet. It is more than a quarter of an inch in diameter, and would act as a drain from the surface to the deeper parts. This question of worm-burrows is one of great practical importance to sanitarians, because, especially after a drought, they may serve to conduct surface water to considerable depths without its really being influenced by that biological filter, the humus. Darwin ^ says that although worms gene- rally live near the surface they may burrow to a considerable depth during long-continued dry weather and severe cold ; the depth varies with the soil. ' See p. 126. "^ Vegetable Mould and Earthworms, p. Ill c^ seq. EARTHWORMS 81 " In a bed of fine sand overlying the chalk which had never been disturbed, a worm was cut into two at fifty-five inches, and another was found here at Down in December at the bottom of its burrow at sixty-one inches beneath the surface. Lastly, in earth which had not been disturbed for many centuries a worm was met with at a depth of sixty- six inches, and this was in the middle of August. The burrows are lined with viscid earth, voided by the worm, which gives at once smoothness and a certain amount of durability to the burrow." Then, again, we must not forget the effect of harvest on the soil. Before harvest the amount of moisture retained upon the growing plant and absorbed by the still active root would prevent anything except the heaviest rain from penetrating, although even at such a time one must admit that even half a pint of water, if thrown on a suitable place, might travel via clay- crack and worm-burrow to a depth of five feet or more. When harvest begins not only is the earth deprived of its green protecting mantle, but the upward drainage of the root action ceases, and with the falling tempera- ture of autumn and the lessened evaporation the rain which falls has an ever-increasing power of penetrating the soil. In a hop garden the first step in harvesting is the removal of the pole, and the hole thus left is capable of conducting rain water to a depth in the soil of two feet or more. If, therefore, there be open-jointed stoneware pipes in a hop garden at a depth of two or three feet from the surface, it is possible, nay, likely, that when the hop-poles are removed a surface channel three or four inches in diameter may communicate with these pipes and a G 82 PRACTICAL CONSIDERATIONS heavy rain may wash solid matters into them from the surface. There are other practical matters which need con- sideration in relation to liability of springs to suffer from surface contaminations. If a plant or tree dies — be it hop, beech, hazel, or what not— the roots, instead of helping the upward drainage of the soil, and preventing surface water from reaching the springs, may serve as a direct guiding channel from the surface to the spring. And if the spring be artificially main- tained by under-draining it with open-jointed pipes (an operation which involves a considerable disturbance of the ground and its artificial re-making), this danger is considerably increased. Burrowing animals are necessarily a danger in this connection, and if rats or rabbits establish themselves anywhere near the out- crop of a spring, they must be exterminated. Eats and rabbits sometimes burrow very deeply, but I have not been able to get any authentic statement as to the maximum depth in the soil to which they may penetrate. Eats are animals which the sanitarian is bound to regard with some suspicion. In relation to the plague they seem to be a very definite danger, and when they crawl from the sewers (their favourite lurking place in towns) to our houses it is possible that they may be at least as dangerous as sewer gas. Eats occasionally make their homes in dung-heaps, especially if such heaps be made in outlying places and are long neglected. It is well known that they invade cornricks, in spite of elaborate precautions, but it is safe to regard the rat as a haunter of foul places and a lover of filth, and its presence among us is often due to our permitting accumulations of filth, and our delay in putting filth to its proper use. SPRINGS 83 Although it is probable that a very few inches of soil may, if properly tilled and cultivated, serve as an efficient protection to the subsoil water, we must never- theless be mindful of the accidents which may serve to conduct filth from the surface to the springs. The danger of having a catch-pit flooded from the surface is one which can easily be guarded against by covering with suitable structures. The ground above the outcrop of a spring ought to be carefully turfed to a point which is six or seven feet above the level of the spring. A spring used as a water-supply must be very carefully watched. If the water become turbid or if a worm find an entrance to the catch-pit the use of such water should be discontinued, or it must be boiled and filtered until the cause of the turbidity be satisfactorily demon- strated. Such springs should always be carefully inspected during heavy rains, because it is at such times especially that shallow springs establish surface relations. The question arises whether it is safe to allow the gathering ground of a spring to be cultivated. This is a national question of the very greatest importance. No nation which is dependent upon its native soil for food production could possibly afford to raise such a question. What would a Chinese say if you told him that the water of his well contained a trace of ammonia and had a permanent hardness above the local standard, and therefore his tea-gardens and rice-fields must remain unmanured and be converted to permanent pastures ? His answer to the * foreign devil ' who ventured to pro- pound such a theory had better go unrecorded. But in China they boil the water before drinking it and they do not seek to fix the responsibility for the absolute purity of the water of a district upon a single underpaid 84 PRACTICAL CONSIDERATIONS individual ; nor do they talk about ' manslaughter ' when a break-down in the arrangements from some cause, natural or artificial, brings about an outbreak of disease. Provided there be a fairly thick layer of earth above the spring I am inclined to think that there is safety rather than danger in the cultivation of the overlying soil. Any spring which is covered by seven feet of soil — that is, six inches more than the depth of the deepest recorded earthworm — might be considered safe from the risk of unchanged organic matter soaking into it from above. ^ In the first place, the cultivation of the land ensures that it is visited more or less frequently by individuals more or less intelligent. A gathering ground for water which is remote from the haunts of man has dangers of its own. Eats or rabbits may burrow in it and these as well as other animals and birds may pro- vokingly die in the runnels which primarily collect the rain-water, and I cannot understand how anybody who has ever walked over a moor can maintain the thesis that water running off a neglected waste is safer to drink than that which has percolated through well-cultivated land. Last year I visited a spring which was being used for public purposes and which was and had been sup- plying water of excellent quality. The spring, which rose in a little copse lying in a natural dell in a remote and seldom visited spot, was enclosed and protected against surface washings which the configuration of the ground would certainly conduct towards it in times of flood. Some of the trees were dead and their stumps • For the same reason, although I agree with Dr. M. Cameron, I am of opinion that the first eight feet of all ' shallow ' wells should have an impermeable lining. ENTERIC FEVER 85 and roots were permeated with fungi and were rotten, and one could not but regard it as possible that these rotten roots might serve as conducting channels from the surface to the water which was running beneath to the neighbouring town. Possibly the workings of rabbits or other burrowing beasts had hastened the death of some of the trees. If so, the burrows might run very close above the gathering water. Further, there was evidence to show that this dell was visited by an occasional tramp and had been made a playground by the children from the nearest group of cottages. It is clear that the non-cultivation of this particular spot was a source of danger rather than of safety to the purity of the spring. Enteric fever is a disease especially liable to become epidemic in the autumn. The autumn is the time of year when after removal of the crops the parched earth is soaked, and it is also the time of year when there are large accumulations of manurial matters waiting to be spread upon the land. In the summer the yield of springs is seldom increased no matter how heavy may be the rains. The water which falls upon the earth is all absorbed by the roots of growing plants and to a large extent mounts upwards in the plant to help metabolism and to quicken growth. With the ripening and harvesting of the crops root action ceases, water which falls upon the earth tends more and more to percolate, and when the early frosts have given their death-blow to the greenery of summer then the springs begin to rise and to yield more water. The nitrification and final solution of organic matter in the soil goes forward mainly, if not entirely, in the upper layer, and it is doubtful if any appreciable amount of oxidation takes place in the parts which are beyond the reach of 86 PRACTICAL CONSIDERATIONS tillage. A certain proportion of the mineralised organic matter necessarily escapes absorption and percolates with the water, and if there be much unused nitrates remaining in the soil after harvest the amount which percolates to the springs may be considerable. If nitrates be placed upon the soil in the form of artificial manures they are often dissolved and washed beyond the reach of plant roots with the first heavy shower. Not only nitrates but soluble salts of ammonia are placed on the ground in large quantities, and the presence of free ammonia in the drainage water of culti- vated land which has been artificially manured need not be an indication of pollution in the proper sense. It must be very hazardous to draw just conclusions as to the wholesomeness or otherwise of water from the amount of nitrates in it. AGRICULTURE 87 CHAPTEE X AGBIC ULTUBE The facts with which we have been dealing in these lectures show: — 1. That there are certain organisms which are indigenous to the soil and ubiquitous. These organisms, if they contaminate a surgical wound or are inoculated, may cause septicaemia, erysipelas, malignant oedema, or tetanus. They are very possibly necessary saprophytes, and we recognise that it is useless to attempt to * stamp out ' the germs of these surgical contagia, although (thanks to Lord Lister) the surgeon is able to pro- tect his patient from the evils which arise from them and to prevent their cultivation in hospitals. Apart from acci- dental inoculation these organisms are not dangerous. We must often swallow them with our food and drink and inhale them with our breath and no practical harm results. These contagia are persistent in the soil and are probably most common in soils which are richest in organic matter. 2. The contagium of anthrax is appa- rently difficult to eradicate from a soil which has once been contaminated with it. This is probably due to the fact of sporulation and to the spore being very resistant to external influences of all kinds. The evidence, such as it is, points to the fact that in temperate countries at least the contagium dies out of the soil in time. M. Pasteur's experiments were vitiated by the circum- 88 AGRICULTURE stance that they were made in districts where the disease was and had been rife. More information is needed as to how far the infection of animals depends upon wounds of the skin or mucous membrane and on the vulnerability of the animals by the mal -hygienic conditions in which they live. It is possible that in tropical countries the Bacillus anthracis is indigenous to the soil. Man apparently does not acquire anthrax by inhaling or swallowing pulverised earth. He is always infected through the medium of infected animals or their skins, flesh, or wool. 3. To what extent malaria is directly a soil disease, apart from the mosquito as a connecting link, is in the present state of our knowledge doubtful. There is no doubt, however, that malaria disappears before drainage and cultivation. 4. With regard to enteric fever, diarrhoea, plague, and some other diseases there can be no doubt that they are all favoured by filth, although we are ignorant of the precise way in which filth favours the occurrence of these diseases. Some might say that a filth disease is a soil disease and that there is no line of demarcation between the two. This is true, but it is nevertheless very necessary for practical purposes to distinguish the one from the other. We are all agreed that it is dangerous to allow the purlieus of a house to become sodden with liquid filth, but it might be equally dangerous to the public health to encourage the idea that it is dangerous to dung the land for fear of inoculating it with infectious disease. Happily from the laboratories we get comfort in this matter. Sidney Martin has shown (as Dempster had previously shown with regard to peat) that * virgin soil,' whether sandy or peaty, is, even when sterilised, fatal to the Bacillus typhosus, and one naturally asks. What is virginity ? and whether cultivated soils by DUNG 89 excessive production do not tend, paradoxical as the question may sound, to return to that condition of vir- ginity in which they are able to grapple with infective organisms ? The evidence goes to show that cultivation and production are the enemies of dung infections. Robertson and Gibson found that a growth of grass was fatal to the Bacillus typhosus. That dung contagia must be destroyed or their virulence be diminished by tillage is self-evident. Were it otherwise our race must long since have been extinguished. The race which has shown the greatest persistence in this world (the Chinese) is precisely that one which has systematically inoculated its native soil with dung contagia for three or four millennia. Politically they are said to be sick, but physically and economically they are * going strong ' and are likely to continue. 5. The fact that most of the alleged soil diseases are more rife in the crowded centres of population than in the rural districts is a fact which must not be lost sight of. Whether this be due to the greater vulnerability of town populations or to the soakage of the purlieus of the house from leaking sewers it is difficult to say. In any case it is incontestable that soil diseases (so-called) are most rife precisely in those spots where the ground is not cultivated. Infective organisms contained in dung have to run the gauntlet of many enemies, such as dogs, sparrows, rats, flies, maggots, beetles, earthworms, moles, sunlight, fresh air, innumerable saprophytes (both aerobic and anaerobic), and the chemical action of the roots of plants. Of course, there may be spores which emerge from these ordeals unharmed and still virulent, but it is evident that, being mortal as we are, they are likely to succumb before the digestive and disintegrating processes which they encounter. The bulk of the evidence goes 90 AGRICULTURE to show that contagia must be largely destroyed in the soil and that agriculture is really the corner-stone of preventive medicine. It becomes of great importance, therefore, to devise means by which ^ the fertilising material of our towns may be applied to the soil with safety and despatch. I may be pardoned for reverting to the method of dealing with human excreta which I have practised now for twelve years in my experimental garden at Andover : (1) the excreta are moved every day so that there is no accumulation of filth near the dwelling ; (2) they are put just below the surface of freshly-dug ground so that they are out of the reach of flies ; and (3) the ground is planted with plants of the cabbage order as quickly as may be, so that very soon there is no possibility of dust being blown off the surface of the ground, and the mass of living cabbage leaves freshens the air. I cannot believe that dust from agricultural land is a danger in this country, whatever it may be in the tropics. In my garden the ground treated in the manner stated, apart from the growth of cabbages, soon becomes coated with a green growth of algae. Mr. A. Gepp, of the Natural History Museum, who visited my garden in 1898, took some of this growth away and very kindly examined it and he pronounced it to consist of algae — " chiefly Vaucheria sessilis (in good fruiting state) with a little ulothrix, a gloeocystis, and an oscillatoria." Such a growth effectually prevents the possibility of dust. Dr. Samuel Hyde,^ speaking on the open-air treatment of consumption, says : " Sparseness of vege- tation, like thinness of population, is a climatic factor favourable to the treatment of consumption. Where vegetable life abounds there vegetable decomposition • J3n^ Mod. Jour. October 8, 1898. VEGETATION 91 must also abound and vice versa. Wherever there is life we have a corresponding amount of death accompanied necessarily by the products of decomposition." This is quite true and our experience teaches us that, provided the supply of food be adequate, a high level of health may be maintained in places where there is little or no vegetation, as upon the sea and on alpine heights and in arctic solitudes. " Wherever there is life," says Dr. Hyde, " we have a corresponding amount of death." That is true, but the converse is also true, and we may say that wherever there is death we have the potentiality of a corresponding amount of life. I believe that what I have called the circulation of organic matter is a beneficent fact from which there is no escape, and that whether we derive good or ill from the inevitable processes of death and decay depends very much upon ourselves. We must never forget that vegetation purifies the soil, freshens the air, rests the eye, and prevents dust, and these facts must be recognised as to a great extent counterbalancing the evils of dead leaves. There are always pros and cons which have to be weighed. Nothing makes entirely for good or entirely for evil and we have always to balance our accounts and to see whether the general effect be good or ill. The British sanitarian is so circumstanced that he need not trouble himself at all about the most important of all sanitary considerations — viz. food-supply. He is busy in burning or washing into the sea every kind of fertilising matter, and if a general coal strike or a war were suddenly to bring famine with its attendant diseases to our doors he would protest that that was no concern of his. With our steadily diminishing birth- rate and the daily increase of institutions for the recep- tion of those whose moral, mental, or physical diseases 92 AGRICULTURE prevent them from earning their own living, it is difficult to believe that the stamina of our highly civilised urban populations is increasing. Apart from the question of food-supply, it is, I believe, absolutely necessary to encourage agriculture in order that our race may be maintained in vigour. The strong contrast which exists between the agriculturist and the town worker in the matter of health is well known. Table {deduced from Table IV. of the Supplement to the Fifty-fifth Beport of the Registrar-General) showing the mortality from certain specified causes in each of three sections of occupied males^ as com- pared with that among all occupied males, the mor- tality of the latter being taken as 100 in each case. All causes Influenza Alcoholism Eheumatic fever .... Gout Cancer Phthisis Diabetes Diseases of the nervous system . Diseases of the circulatory system Diseases of the respiratory system Diseases of the liver . Other diseases of the digestive) system . . . . i Diseases of the urinary system . Accident Suicide Other causes .... h III upied briots llll a |!^3 ^^|5 i^U < < 100 120 131 72 100 100 100 100 100 138 146 54 100 100 114 86 100 300 100 100 100 134 109 91 100 150 121 73 100 114 100 100 100 107 132 77 100 107 122 75 100 124 166 51 100 111 119 89 100 100 129 82 100 137 122 78 100 86 105 79 100 129 114 86 100 91 130 76 Dr. Tatham's letter to the Kegistrar- General on the mortality of males engaged in certain occupations in COMPARATIVE MORTALITY 93 the three years 1890-92, which constitutes Part II. of the Supplement to the Fifty-fifth Annual Keport to the Eegistrar-General, shows clearly enough that the agricultural classes in this country enjoy a large measure of health. Dr. Tatham's statistics refer to occupied males between the ages of twenty-five and sixty-five years, and the tendency to disease and death is indicated by a mortality figure, the mortality for all males between twenty-five and sixty-five years of age being taken as 100. The preceding table (p. 92) taken from p. 18 of this report shows the mortality of three great classes of the community with perfect clearness. — 1 ll ?.2 1 -1 Is 1 if ii j Ii ^1 1 i < 1 l^ •c bo < 1 All causes 100 72 63 64 59 53 66 70 58 Influenza 100 100 109 112 115 112 112 118 82 Alcoholism . 100 54 31 31 46 31 31 31 31 Eheumatic fever . 100 86 86 71 86 71 71 57 100 Gout .... 100 100 50 50 50 100 50 50 50 Cancer .... 100 91 82 84 82 77 82 86 82 Phthisis 100 73 57 63 43 44 62 70 61 Diabetes 100 100 86 86 143 167 71 71 57 Diseases of nervous sys- tem .... 100 77 62 63 62 50 65 71 57 Diseases of circulatory system 100 75 66 68 61 52 71 75 61 Diseases of respiratory system 100 51 52 49 41 29 58 57 48 Diseases of the liver 100 89 63 59 96 81 48 56 63 Other diseases of diges- tive system 100 82 82 75 96 75 79 75 64 Diseases of urinary sys- tem .... ilOO 78 59 59 71 68 51 56 63 Accident 100 79 63 68 53 54 74 77 39 Suicide .... ■100 86 71 71 100 129 57 50 71 All other causes . 100 76 73 76 65 61 79 86 61 94 AGRICULTURE The preceding table (p. 93) which is deduced from Table IV. shows the mortality from certain specified causes in the agricultural class as a whole and in its several divisions as compared with the standard mor- tality among all occupied males, the latter being taken as 100. Out of the sixteen causes specified in this table, there is only one in which the mortality of agriculturists as a class exceeds that of occupied males generally. The exception is influenza, the mortality from which disease shows an excess equal to 9 per cent. The chief excess under this heading probably occurred in the first quarter of the year 1892, which was marked by a severe outbreak of influenza specially affecting the country districts. The mortality among agricultm'ists from phthisis does not exceed 57 per cent., and that from diseases of the respiratory system does not exceed 52 per cent, of the standard mortality among occupied males, and their mortality from all other diseases of the local class is considerably below the same standard. These tables show conclusively that agriculturists are among the healthiest class in the community and that even the farm labourer in the matter of health is 83 per cent, better than the average. This is a matter of great interest and importance. He is often represented as half-starved, miserably housed, a martyr to rheumatism and poisoned by filthy water. As a matter of fact as regards sobriety and health he might be taken as a model by the rest of the industrial classes. There is another point of view from which agriculture is of great importance. We are beginning to find out that a factory hand who has to keep pace with steam machinery becomes * too old for his work ' at a comparatively early age. Defects of eyesight or hearing or a lessening OLD-AGE PENSIONS v. A GARDEN 95 of acuteness and nimbleness soon unfit a man for employments where dexterity is of more importance than experience. There has been much talk of late of * old-age pensions,' but it must be admitted that even if the financial difficulties of the question could be over- come the prospect of being without employment and existing on a pittance without any true interest in life after the age of fifty-five years is not cheerful. I believe that the practice of agriculture is the only remedy for this, and that the best old-age pension will be found in the possession of an acre or so of land. Not only are the ordinary horticultural operations all possible for a man long after he is capable of attending to machinery, but such a possession would give him an interest in life and he would find that the productiveness of his land would certainly increase with time and in direct proportion to the amount of skill and labour expended in tillage and cultivation and the quantity of organic manure placed upon the soil. The greatest need of our country at the present day I believe to be an increase in the facilities for the transfer of land. Many of the above facts appear to show that the practice of agriculture is absolutely essential, apart from the question of food, for the maintenance of the vigour of our race. Anything which discourages or increases the difficulties of agriculturists can hardly be in the interests of the public health. 96 FERTILITY OF THE SOIL CHAPTER XI THE MAINTENANCE OF THE FERTILITY OF THE SOIL There is much evidence to show that dung is absolutely necessary to maintain the fertility of the soil. In a paper by Sir John Lawes and Sir Henry Gilbert on the valuation of unexhausted manures * the difference between organic manures and mineral manures is well brought out. The lasting effects produced by farmyard manure (14 tons to the acre) are shown in the annexed table : Table I. — Experiments with Farmyard Manure on Permanent Grass Land, every Year Manured 1866-63, Uumanured since Excess of Mauuitjd over TJnmanured 8 years 1856-63 \ 1st crops J 12 years 1864-75 | only i 20 years 1876-96 (1st and 2nd crops) .... Cwt. ill 25i Owt. m 291 Cwt 4 In only one year — 1893, a year of drought — did the manured plot give less produce than the unmanured. The authors say : * It is true that the application of 14 tons of farmyard manm'e per acre per annum for eight years in succession is an unusually heavy dress- ' Journal of the Royal Agricultural Society, vol. viii. 1897, p. 674. BARLEY 97 ing ; but it is of interest to know that the residue was very materially effective for some years, and that it was more or less so for THIETY-TWO YEAKS after the application " (the capital letters are my own). The following table giving experiments with barley tells the same tale. Table II. — Experiments with Barley, 1852-96. Un- manured every Year Mixed Minerals every Year (no nitro- gen) Farmyard Manure Every Year 20 Years 1852-71 ; TJnmanured since 20 years 1852-71 . 25 years 1872-96 . Bushels 20 12| Bushels 27i 161 Bushels 48i 49i Bushels 48i 29 The above table shows that the effect of the farm- yard manure is very appreciable for at least a quarter of a century. It also shows that when farmyard manure was used every year the yield for the final twenty-five years was greater than in the first twenty years. And also that the increase by using mineral manures without nitrogen is appreciable but slight. The use of rape-cake as an organic manure for barley gave interesting results which are set forth in Table III. Table III. — Bape-cake as a Manure for Barley 1852-91. - Rape-cake alone Rape-cake with mixed Mineral Manures and Nitrate of Soda 20 years 1852-71 „ ,, 1872-91 Bushels per acre Bushels per acre 49f 41^ It is to be noticed that the reduction in produce in the second twenty years as compared with the first amounted to more than eight bushels per acre. The 98 MAINTENANCE OF FERTILITY reduction in the second twenty years was, in the opinion of the authors, mainly due to less favourable seasons, but nevertheless it is shown that the yield with farm- yard manure for the twenty-five years 1872-96 was 49 bushels as against 48J for the twenty years 1852-71. The experiments made in growing clover on rich garden soil are of great interest. This has been done for forty years in a part of the Kothamsted kitchen garden which has been in cultivation for two or three centuries. The average yield for the forty years was 59^ cwt., or nearly three tons of hay, which *' would be a very good yield for the crop grown only occasionally in the ordinary course of agriculture." The average yield in the first ten years was much greater than in the subsequent thirty years, and averaged 95^ cwt., and the maximum yield appears to have been about 148 cwt., or nearly seven and a half tons to the acre. In 1857, after the removal of the crops of the fourth year of the experiment, the surface soil nine inches deep contained four times as much nitrogen as the average of the Eothamsted arable soils to the same depth, and nearly five times as much as the exhausted arable land where red clover had failed. The experiments on wheat with artificial manures are equally instructive. Table 1Y.— Showing the Yield of Wheat in Bushels per Acre, Mixed Mineral Manure — y\^ " And Period NH, 172 lb. N Alone AndNH, AndNH, for first 13 years 86 lb. N. 129 lb. N. (1862-64) ; un- manured for last 19 years Plots Plot: Plots Plot 16 13 years 1852-64 . 18f 37| 39 39^ 19 years 1865-83 . l^ 291 m 14| WHEAT 99 In the above experiments we find, no dung being used, that the yield is less in the second period than in the first, and that when the large amounts of artificial manure were withdrawn in Plot 16 the yield dropped almost at once. The authors say : " There is, in fact, abundant evidence to show that there is but little effective manure residue after the growth of a grain crop by the application of ammonium salts ; and there is little doubt that the produce of one and a half bushels of grain and its straw per acre per annum more over the nineteen years after the cessation of the application of ammonium salts than on Plot 5 with the mineral manure alone is, so far as it is to be attributed to residue, mainly due to the increased crop residue — stubble and roots accumulated during the thirteen years of the application ; and much the same may be said of the after-effects when grain crops have been grown with nitrate of soda." Again : " When organic matter, animal or vegetable, is applied to the soil as manure, its complete decay and the complete liberation of its fertilising constituents extend over a considerable period of time. Poor land cannot be suddenly brought into condition by the consumption on the farm of purchased foods. Nor can condition — that is, accumulated fertility — be at once withdrawn by suddenly stopping the use of foods." Food-supply. — Sir William Crookes, the President of the British Association, in his address (Bristol, 1898) drew attention to the fact that if population continued to increase we might expect to be short of wheat. Our remedy was to increase the fertility of the wheat-growing area of the world, and taking, as was perhaps but natural, a purely chemical view of fertility, he put forward the proposition that the productiveness of the loo MAINTENANCE OF FERTILITY soil might be expected to bear a direct ratio to the amount of fixed nitrogen which is applied to it, and he found comfort in the fact that after the exhaustion of the nitre beds of Chili and the guano beds of Peru, the chemist of the future would be able, by the aid of electricity generated by Niagara and other natural forces, to fix the atmospheric nitrogen for the benefit of the farmer. In the course of his address Sir William Crookes made allusion to the sewage question in the following words : " There is still another and invaluable source of fixed nitrogen. I mean the treasure locked up in the sewage and drainage of our towns. Individually the amount so lost is triflmg, but multiply the loss by the number of inhabitants, and we have the startling fact that in the United Kingdom we are content to hurry down our drains and watercourses into the sea fixed nitrogen to the amount of no less than 16,000,000^. per annum. This unspeakable waste continues, and no effective and universal method is yet contrived of converting sewage into corn. Of this barbaric waste of manurial con- stituents Liebig nearly half a century ago wrote in these prophetic words : * Nothing will more certainly consummate the ruin of England than a scarcity of fertilisers — it means a scarcity of food. It is impossible that such a sinful violation of the divine laws of Nature should for ever remain unpunished, and the time will probably come for England sooner than any other country when, with all her wealth in gold, iron, and coal, she will be unable to buy one-thousandth part of the food which she has during hmidreds of years thrown recklessly away.' The more widely this wasteful system is extended, recklessly returning to the sea what we have TILLAGE loi r taken from the land, the more surely and quickly will the finite stocks of nitrogen locked up in the soils of the world become exhausted. Let us remember that the plant creates nothing ; there is nothing in bread which is not absorbed from the soil, and unless the abstracted nitrogen is returned to the soil its fertility must ultimately be exhausted." Sir John Lawes and Sir Henry Gilbert, in a com- munication addressed to the Times on December 2, 1898, point out that even supposing that atmospheric nitrogen could be fixed at a remunerative price, the addition of nitrates without the addition of the other mineral con- stituents necessary for wheat growing would be of no permanent use ; but they express the opinion that the stores of nitrogen and other fertilising salts existing in our own soils and the soils of foreign countries can be made available by thorough tillage and proper rotation of crops. The land wants labour, and the production of wheat is likely to be proportionate to its market value. They point out that the average wheat production of the ujimanured plot at Kothamsted (over thirteen bushels) is greater than the average of the whole of the United States, a fact mainly due to proper tillage and thorough weeding. It is tolerably evident that fertility is not merely a chemical question. The year 1898 was remarkable for a fine wheat crop in this country. The yield is said to have averaged thirty-five bushels instead of twenty-eight or twenty-nine bushels per acre. Sir John Lawes, in his annual letter to the Times (October 22, 1898) on * The Wheat Crop of 1898,' states that at Kothamsted the yield on the experimental plots was as under (p. 102). I02 MAINTENANCE OF FERTILITY Table 1.— Wheat Crop in 1898. Bushels per Cwt. of acre straw Plot 3, unmanured 12 12^ Plot 9, nitrates 23f 33| Plot 7, ammonia salts .... 28| 44f Plots, „ „ . . . . 29f 54f Plot 2, farmyard manm-e 38 55f In 1898 at Kothamsted the plot dressed with nitrate of soda yielded twenty-three bushels, as against thirty- eight bushels on the farmyard plot, and in explanation Sir John Lawes says : " For only the second time during a period of more than forty years the wheat plant was much injured where we have used the heaviest dressing of nitrate of soda for want of enough rain to form and distribute a sufficiently dilute solution of it; and a similar result occurred in the year of drought of 1893 ; whilst in this year, 1898, the barley plant was much injured with only half the amount of nitrate applied." Sir John Lawes also gives the average yield of these five plots for periods extending over forty-six years. Table \l,— Wheat Crop, 1852-97. - Un- manured Farm- yard Ammonia salt Ammonia salt Nitrate of soda 36 years 1852-87 . 10 years 1888-97 . 46 years 1852-97 . 13 12J 12| 33f 40f 35J 32| 33| 36i 37| 36| 36f 33| 36i From the above table it will be observed that not only has farmyard manure proved to be practically the equal of artificial manures for nearly half a century, but that during the last ten years the yield from it has been considerably more than that of any of the artificially manured plots. It is interesting to observe, also, that VALUE OF PLANT-ROOTS 103 had the wheat-growing area of this country in the year 1898 been sprinkled with nitrate of soda after the manner of Plot 9 at Eothamsted, the yield might have averaged only twenty-three bushels instead of thirty-five bushels. On 2,000,000 acres, which is approximately the wheat area of the United Kingdom for 1898, this means a deficit of 24,000,000 bushels or 3,000,000 quarters. The chemical analysis of a soil often fails to give the clue to its fertility or sterility. Mr. Kobert Elliot, in a paper on * The Value of Plant-roots as Tillers of the Soil,' ^ quotes Sir John Lawes to the effect that " All our experiments tend to show that it is the physical con- dition of the soil — its capacity for absorbing and retain- ing water, its permeability to roots, and its capacity for absorbing and radiating heat — that is of more importance than its, strictly speaking, chemical composition." It is, in fact, abundantly evident that the biological side of fertility is quite as important as the chemical, and that organic manures are absolutely necessary to maintain the fertility of the soil, and that of all organic manure there is nothing to be compared with dung. If all that comes from the land be returned to it there can be no reason why the agriculturist should trouble himself with chemical theories. He has only by labour to maintain the soil in a good physical condition and he may rest assured that its fertility will increase. ' Journal of the Boyal Agricultural Society, vol. viii. p. 469. I04 SANITATION IN HOLLAND CHAPTER XII SANITATION IN HOLLAND In Holland the connection of sanitation with agriculture is far closer than with us, and it is possible that we may derive some useful hints from our neighbours. In Holland the sanitary problems are of a formidable kind. The level of the country varies from a few feet above to a few feet below the mean level of the German Ocean, and it is needless here to recount how the Dutch people, marvellous for their shrewdness and untiring industry, have maintained a successful warfare against the forces of Nature. With the exception of two or three incon- siderable areas the whole of the Kingdom of the Nether- lands is a flat plain intersected at very frequent intervals by canals and rivers. These watercourses are all sluggish and in some of them the slow current is maintained artificially by pumping. It may be said that every Dutchman lives within a few yards of a watercourse of some kind, be it ditch or canal. These canals form a very cheap and admirable means of internal communi- cation, and in consequence the barge population is very large indeed. The population of Holland tends steadily to increase, such increase being most marked in the big towns. In no country in Europe, probably, has the state of public health improved more remarkably than in DEATH-RATE los Holland. This is well shown by the following table which is taken from the 'Annuaire Statistique de la Ville d' Amsterdam,' 1896. The decline of the death- rate has been uniform and continuous since 1884, but for the sake of conciseness the years 1877, 1880, and every fourth year thereafter alone have been given. Nomhre des decbs {mort-nes exclus) par 100,000 habi- tants de la population moyenne dans les cinq grandes villes des Pays-BaSy amiees 1877-96. Amster- Eotter- s'Graven- Gronin- Les 5 Annies dam (iam hage Utrecht gen villes 1877 25,00 25,32 21,66 23,91 29,51 24,70 1880 27,00 24,65 23,38 27,10 24,39 25,74 1884 27,87 27,01 24,87 26,38 22,00 26,67 1888 21,82 21,26 20,11 22,56 20,04 21,38 1892 19,78 23,26 20,32 23,84 17,27 20,89 1896 17,77 18,27 16,27 19,04 16,01 17,65 The causes of this improvement in the death-rate are probably the same as have operated throughout Western Europe generally. These causes are : (1) the improve- ment in the physical and moral condition of the lower strata of society ; (2) sanitation in its widest sense ; (3) the rapid increase of population, especially in the towns, causing a dilution of the high death-rates in the old crowded portions by the lower death-rates of new settlers in the outskirts ; and (4) the decrease in the birth-rates. In Holland, as in England, the importance of pure water, especially for town populations, is abundantly recognised, and public supplies have, within recent years, been carefully protected from pollution and filtered before being distributed. The risk of drinking canal water must have been very great indeed. The mode of dealing with faecal matter is necessarily different from ours. In Holland water-closets are the exception io6 SANITATION IN HOLLAND and not the rule, and while the slop water of the houses is allowed to flow into the canals, the fasces are collected and used for agricultural purposes. During a visit to Holland in September, 1898, I was able to obtain the Dutch death-returns for 1885-89 and for 1889-94, a period of ten years in all. For this I have to thank Mr. Verryn Stuart, the secretary of the Statistical Com- mission at The Hague, who most courteously procured for me the volumes containing the returns in question. The Netherlands, 1885-1890 1890-94 Provinces 31 ^1 III Hi. pi North Brabant Guelderland South Holland North Holland Zealand . Utrecht . Friesland . Overyssel . Groningen Drenthe . Limburg . Kingdom . 1885-94 Kingdom . 60,436 53,706 110,964 90,959 20,456 25,837 31,851 33,765 25,594 13,653 26,352 493,573 994,506 245 313 563 621 93 166 263 280 253 90 100 2,987 5,970 1 in 247 1 „ 171 1 „ 197 1 „ 146 1 „ 220 1 „ 156 1 „ 121 1 „ 120 1 „ 101 1 „ 152 1 „ 263 1 „ 165 1 „ 166 62,808 55,713 112,139 89,494 20,390 26,098 30,893 34,145 25,988 14,564 28,701 500,933 257 308 462 713 125 184 227 238 237 107 125 2,983 1 in 244 1 „ 181 1 „ 243 1 „ 125 1 „ 163 1 „ 142 1 „ 137 1 „ 143 1 „ 110 1 „ 136 1 „ 229 1 „ 168 Taking the population for 1885-94 at 4,500,000, the average annual death-rate is 18*26, and the typhoid fever and typhus fever death-rate is 0*13 per 1,000. It will be observed that in Holland, generally, the death-rate from enteric fever compares favourably with our own. Knowing as we do the great risk of drinking sluggish water liable to faecal contamination (which has ENTERIC FEVER 107 been exemplified in the Tees valley), the low enteric death-rate in Holland is not a little remarkable. Enteric being a fever of slow and insidious onset, it is impossible in sporadic cases to say where or how the patient may have been infected, and in cities with an ever-shifting population this difficulty is accentuated. That being the case it will not be without interest if I give a few particulars concerning the provinces of Groningen and Friesland, which I visited in the vacation of 1898. These two provinces are almost entirely devoted to dairy farming, the breeding of horses and cattle, and agriculture. The shifting and travelling population is a small one, and it is here, if anywhere, that we may learn the effect of local habits and customs on the public health. The town of Groningen with 63,863 inhabitants is in point of population the fifth town in Holland, and a reference to the table will show that the improvement in its death-rate in the past twenty years has been as remarkable as that observed in the other Dutch cities or in any town or city in this country. In this town as also in Leeuwarden, the capital of Friesland, and in the great majority of Dutch towns, the faecal matter is collected in pails, and it is probable that in the whole extent of the two northern provinces of Groningen and Friesland there is not a water-closet to be found. The whole of the faecal matter is scrupulously and religiously collected and returned to the soil. Dutch cleanliness is proverbial, and certainly I have never been in a town so exquisitely clean as is the town of Groningen. The accumulation of ordure in the streets and backyards is simply not tolerated, and the inhabi- tants co-operate with the scavengers in clearing away all refuse as quickly as possible. The collection of io8 SANITATION IN HOLLAND faecal matter is very simple. The closet-pails are much smaller than those which are commonly used in this country, and they are emptied twice or thrice a week or daily if the householder is ready to pay a small fee. The collecting cart is really a tank upon wheels with a sort of hood projecting behind like the hood of a carriage facing the wrong way. The pails are brought out, and the man and pail are hidden by the hood as the con- tents are simply tipped into the tank. The pails even when full being such as one man can lift easily, the collection is probably ten times as rapid as is the case in those English towns which make use of huge two- man pails which weigh 50 lb. and more when empty. Again it is obvious that the Groningen authorities do not make the mistake of hauling about an immense weight of pails, which adds enormously to the expense. The depot where the material is collected is on the outskirts of the town, where a wharf has been con- structed with a view to its removal by barge for the purposes of the farmer. Here, again, the arrange- ments are very simple. The stuff is simply stacked beneath rough sheds covered with corrugated iron. The men employed have found out exactly how to do it, and by arranging a layer of street sweepings and rubbish (dung, straw, paper, rags, &c.) with peat ashes (the fuel used in this district is almost exclusively peat) alternately with a layer of pail contents, the whole mass drains and consolidates into a very rich black manure which the farmer highly appreciates. The floor of the depot is concreted and provided with channels so that the urine drains away into a large tank whence it is pumped into barges for the use of the agriculturist. Considering the work which went on in it, this depot was wonderfully neat, the stacks were as evenly made DISPOSAL OF EXCRETA 109 as the best hay stacks, and the paths between them were quite free from befoulments. The smell from the putrid draining was, to say the least, powerful, but the solid stuff soon ceases to be very offensive. There were large numbers of flies in this depot, but I frequently remarked that the flies in the town of Groningen were not nearly so troublesome as is the case in cities less carefully scavenged. In the town of Leeuwarden the pails are taken to and from the depot, but the pails are much smaller and lighter than those in use in England, so that fifty- four of them (three tiers of eighteen each) can be carried on a one-horse lorry. In the ten years 1885-94 there were in each of the provinces of Groningen and Friesland 490 deaths from enteric fever and typhus fever, 980 deaths in all or an average of 98 per annum in a population of some 600,000, giving a rate for typhus fever and enteric fever of 0*1 6 per 1,000. During the same period there were 97 deaths from the same cause in the town of Groningen and twenty-seven in the town of Leeuwarden, or 124, giving a yearly average of 12*4. These figures are not large, but they show that as regards these diseases the condition of Groningen was slightly worse than the town of Leeuwarden. As in England so in Holland, the death-rate from enteric fever has been falling steadily, and the returns for the last available year (1897) are very instructive. From these returns I find that in the province of Groningen with 296,521 inhabitants there were 23 deaths from enteric fever in eighteen parishes, giving a death-rate of 0-08, and in the province of Friesland, with 389,425 inhabitants, there were 19 deaths from enteric fever in twelve different parishes, giving a death-rate of 0*056 per 1,000. It is a remarkable and most interesting no SANITATION IN HOLLAND fact that in 1897 there was no death from enteric fever in either of the capital towns of Groningen or Leeuwarden, containing over 95,000 inhabitants (Gron- ingen 63,863 and Leeuwarden 31,598). The figures given above must be taken to show that in these two provinces there is no serious endemicity of enteric fever. When we consider that dairy farming is the staple industry of these provinces, that milk, which is most sensitive to typhoid fever infection, is everywhere abundant, and that human excreta contain- ing a certain proportion of typhoid fever excreta are used, and have been used for ages, to manure this fertile district, which lies almost in the water, the com- parative freedom from enteric fever seems remarkable and very full of instruction. These facts seem to me to afford a very large measure of proof that there is no inherent danger in the methods of sanitation pursued in Groningen and Friesland and, in fact, in Holland generally. Dutchmen are eminently shrewd, thrifty, industrious, and methodical. The in- teriors of their dwelling-houses and cattle-houses are, as a rule, exquisitely clean and neat, and on the farm one is constantly confronted with the same character- istics. In the agricultural districts nothing is ever thrown into the ditches or watercourses. On the contrary, everything is taken out of them that can be turned to profit. These ditches must be kept clean and the banks of them need constant attention. The banks are kept in repair largely by the mud which is removed from the ditch, and whatever the ditch will grow in the shape of rush or weed or willow is all carefully harvested and turned to account for thatching or for litter or for basket work. The Dutch farmer never feels the effect of drought and this is one secret AGRICULTURE in of his success. His endless watercourses serve for fences and afford a cheap and ready means of transport. They are a source of small profit in various ways, and most certainly they are never allowed to carry away from the farm anything which possesses manurial value. The methods of the Dutch agriculturist are slow and sure and steady. He has had to contend with the forces of Nature and has got the upper hand, and is now ahead of the whole world in exacting labour and profit from wind and water. It is very difficult to appraise the fertility of a district. The area of Friesland is given as 331,030 hectares, of which 206,718 are pasture and 47,317 are arable. These 254,035 hectares of land under cultiva- tion are farmed by 14,049 farmers, of whom 5,374 are freeholders. The average holding would thus appear to be 18 hectares or about 43 acres, and as one travels through the province the substantial farmhouses appear to be dotted over the country with something like mathematical precision, and the cattle (of which there were 233,582 in the province in 1897) appear to be innumerable. Groningen contains a considerable amount of waste land. The pastures are less extensive than in Friesland and there is a greater area under the plough. In 1897 I find that in Groningen 7,351 hectares of wheat pro- duced 35 hectolitres per hectare; 4,702 hectares of barley produced 41 hectolitres per hectare ; and 33,135 hectares of oats produced 57 hectolitres per hectare. These returns are large and are the equivalents of 40 bushels of wheat to the acre, 46 bushels of barley to the acre, and 65 bushels of oats to the acre. Agricultural returns for a single year are not, perhaps, of great value, but these figures show at least that the 112 SANITATION IN HOLLAND land is capable of an enormous yield. The yield of oats especially appears to be very large. The returns issued by the Board of Agriculture show that in 1896 we imported from Holland 923 horses, 663,196 cwt. of dead meat, over 500,000 cwt. of butter and cheese, 861,887 cwt. of margarine, 217,891 cwt. of milk and condensed milk, 375,116 bushels of fresh fruit (apples, pears, cherries, plums, &c.), and 1,581,386 bushels of onions. In addition we imported from Holland 609,710 cwt. of grain and 40,127 tons of hay, and no mention is made of the horticultural products in the form of * Dutch bulbs,' &c., which we import in enormous quantities. In the United Kingdom of Great Britain and Ireland there are, including waste lands, 77,672,000 acres sup- porting a population of 40,000,000, and in Holland there are (excluding lakes and rivers) 7,786,000 acres supporting 4,894,000, so that Holland supports a bigger population per acre than the United Kingdom. In the United Kingdom the area under cultivation (crops and grass) amounted to 47,868,553 acres in 1897, and this figure appears to be slightly decreasing. In Holland in 1895 the total area under crops and grass was 5,149,817 acres, showing an increase of 95,000 acres on the preceding three years. In the United Kingdom there are 1*2 acre of cultivated land per head of the population and in Holland there are 1*05 acre of cultivated land per head of the population. Statistics prove that Holland is a most fertile and productive country, but one requires to travel through it in order to be fully impressed with the extraordinary amount of produce which the Dutchman exacts from the soil. In Groningen and Friesland one cannot but be struck with the well-to-do look of the population. If there DUTCH PERSEVERANCE 113 be wretchedness and squalor it is not visible to the traveller, and must be, in any case, relatively small in amount. The people are well nourished and well clothed, the towns are handsome and clean, and the shops are excellent. Perhaps no better evidence of the high level of comfort which pertains in this purely agricultural country can be given than the fact (which I take from 'Baedeker's Guide') that the town of Leeuwarden with 31,000 inhabitants supports twenty- five firms of jewellers and silversmiths who are mainly engaged in making personal and household ornaments for the farmers and their families. Let it not be supposed that the Dutchman owes his position of agricultural supremacy to the * natural ' fertility of the soil of his country. Doubtless he has found a large amount of well-watered pasture land ready to hand, but it is undeniable that some of the very best of his land has been won from the sea, the desert moorland, and the bog, by indomitable pluck and perseverance. Above all, the Dutchman is fully impressed with the necessity of returning to the soil everything that comes out of it. Nobody knows better how to facilitate that circulation of organic matter which is a law of Nature, and he sees that his profit depends upon the complete- ness and rapidity of that circulation and that in farming as in other businesses a rapid turnover of capital is to be aimed at. In Holland everything which has manurial value is religiously returned to the land, and we find that the population is increasing as fast as ours and that the land under cultivation is increas- ing, although the area of land is less per head in Holland than in the United Kingdom. The level of public health is as high in Holland as in the United Kingdom, and an enormous amount of farm, garden, and dairy I 114 SANITATION IN HOLLAND produce is exported to this country where (albeit that many a tract of bog and waste moorland is waiting for the subjugation of civilisation) the land under cultiva- tion is tending to decrease, where manurial wealth is being recklessly burnt or turned into the sea, and where one-half of the population is absolutely ignorant of the uses and value of dung and the other half is, if not ignorant, too squeamish to use it. The municipal accounts of the city of Groningen for the year 1897 show that the total cost of keeping the city clean was 94,596 florins (12 florins = 1Q. The chief items of this expenditure were : Florins Salaries and wages . . 50,615 Horse hire . 21,441 Eepairs to carts . 4,507 Boat hire . 1,500 Brooms . 812 Disinfectants . Sundries . Clearing snow Total . Florins 263 . 4,177 . 11,281 . 94,596 As a set-off against this expenditure the accounts show that the compost resulting from the stacking of ordure and refuse, which amounted to 1,315 barge-loads, was sold for 58,075 florins, and the liquid manure which drained from the stacks, and which is much valued by agriculturists, was sold for 5,339 florins. The total receipts from the sale of manure amounted, therefore, to 63,414 florins, which, deducted from 94,596, gives 31,182 florins (say 2,600/.) as the net cost of cleaning Groningen. Taking the population of Groningen at 63,863, the cost of scavenging works out at something less than half a florin or l^d. per head of the popula- tion. It will be noticed that of the total expenditure (exclusive of clearing snow) very nearly two- thirds go in wages, a great part of which is paid to the poorest class and must in some degree lessen the poor-rate. It appears that the permanent staff consists of 102 persons, GRONINGEN 115 of whom fifty-six with twenty-eight horses and carts are engaged mainly in collecting ordure, and twenty people with ten horses and carts in collecting ashes and refuse. For cleaning sewers, canals, gutters, and gratings nine- teen men are employed. The collection of ordure is done in the early morning before 10 o'clock. I 2 ii6 CARRINGTON MOSS CHAPTER XIII CABBINQTON MOSS This seems to be the place in which to allude to the spirited action of the city of Manchester, which has reclaimed Carrington Moss and which is reclaiming Chat Moss by fertilising the ground with the organic refuse of the city. The ground is a virgin peat which is admitted to be deadly to one at least of the supposed earth organisms. The experiment is a splendid one, and will certainly be the precursor of similar action elsewhere. I have gathered some figures which may give an idea of the gigantic task with which the Cleans- ing Committee of the city have to grapple. From the report of the Cleansing Department of the city of Man- chester for 1897 I find that 354,364 tons of refuse — very nearly 1,000 tons a day — were disposed of. Stated in cartloads there were of street sweepings, 61,248 ; of * Bell dust,' 9,823 ; of rubbish, 97,658 ; and of night- soil, 240,781 ; total, 409,510. Of the material collected nearly one-third of the weight is lost by evaporation (in the preparation of concentrated manure), leakage, and drainage, and nearly 100,000 tons find their way to the rubbish tip, so that about 140,000 tons remain to be accounted for. Of this 49,342 tons were sent to Car- rington Moss, and over 57,000 tons were disposed of to farmers direct. Over 6,000 tons of concentrated manure (made from 108,000 tons of * day-soil ' or pail- CITY OF MANCHESTER 117 closet contents) sold for more than 17,000^. Nearly 19,000 tons were converted to mortar, and were sold for 4,500Z., and some 9,000 tons of clinkers were used for road-making. The net expenditure of the Cleansing Committee in 1897 amounted to 131,793Z., so that the 354,364 tons of refuse were dealt with at a cost of Is. ^d, per ton. The total cost for the year of the Carrington estate (including rent and interest of capital) was 2,482^.^ The material sent to Carrington in 1897 consisted of 37,082 tons of nightsoil, 587 tons of sweepings and gar- bage, and 11,673 tons of cinders. The Carrington Moss estate, therefore, regarded merely as a dumping ground for garbage and refuse, must be a source of satisfaction to the Cleansing Department of the city of Manchester. On August 11, 1897, I visited Carrington Moss, and had the advantage of being shown over it by Mr. McConnell, the bailiff. Carrington Moss was bought by the Manchester Corporation in 1886. It is ten miles from the city, in close proximity to the famous Chat Moss, from which it is separated by the Manchester Ship Canal, which serves for the transit of material from Manchester. The estate, for which the Corporation gave 38,000^., has an extent of 1,100 acres, of which 600 were wild moss commanding a rental of a shilling an acre for sporting rights. The Corporation has spent 56,000^. on light railways, roads, drainage, rolling-stock, build- ings, &c., making the cost 94,000Z. (The outlay on the estate is given as 82,946Z. in the City Treasurer's Ab- stracts, 1897.) In the nine years 1889-97, 491,686 tons of refuse material have been placed upon Carrington Moss, or very nearly fifty tons per acre per annum. ^ ' In the year ended March 31, 1901, the net cost was 861Z. 15s. ^ In the thirteen years ended March 1901, the total is given as 639,779 tons. ii8 CARRINGTON MOSS The moss has been drained by a series of deep trenches with nearly vertical sides cut at regular intervals. The refuse as it arrives from Manchester is transmitted by means of a light railway to various parts of the estate, where for the most part it is placed in heaps and allowed to * ripen ' before being placed upon the ground. These heaps soon cease to be in the least offensive. Nightsoil is frequently applied directly to the fields. At the time of my visit two barges, estimated to contain eighty tons of refuse, were unloading at the little wharf which has been especially constructed. The hay harvest was just over, and the corn harvest was soon to commence. The crops one and all were in splendid condition. Oats, potatoes, carrots, wheat, and all the other usual farm crops appeared to be first-rate, quality excellent, quantity enormous. The roads were hard and firm, having been brought to this condition by the application of clinker and other forms of hard material from the city. The farm is not quite a dead level, but the inequalities of the surface are very slight, so that from every point the spectator is able to survey an area of very considerable extent. Without previous knowledge there was nothing in the appearance of the farm (except the deep trenches) to indicate the character of the subsoil. All indications of bog had completely vanished. On reaching Mr. McConnell's house we walked out upon a pretty lawn surrounded by a flower-border brilliant with carnations and the ordinary garden plants. The lawn was firm and perfectly dry, and I was not prepared for the de- monstration which I was to have of the character of the subsoil. Taking an iron rod having a length of 11^ feet and a diameter of about half an inch, Mr. McConnell with one hand drove it through the turf of his lawn completely up to the handle. I then did the same thing. THE SOIL 119 As the rod passed through the first foot or so there was some resistance and a sense of grittiness was imparted to the hand, but, this first obstruction passed, the descent of the rod was progressively easier until it was finally stopped by the handle resting on the lawn. On with- drawing the rod the lower half was found to be wet while the upper part was dry. To the upper half clung a little grit and peaty earth, the lower half was clean but wet. It was then only that one recognised that this fertile paradise was literally floating. Mr. McConnell informs me that Carrington Moss is everywhere about twelve feet in depth and that the variations in depth are very slight ; whereas Chat Moss, although distant only a few miles, has a depth which varies from four to over thirty feet. On Chat Moss, where the digging of drainage trenches was in progress, I examined the peat which had been removed. These trenches are dug to a depth of about four feet to begin with. The peat near the surface had the ordinary fibrous character, whereas that from the bottom appeared to the naked eye to be smooth and structureless and saturated with moisture. It looked like brown jelly. The moss resembles a huge sponge. Mr. McConnell states that the surface of Carrington Moss is gradually sinking ; that whereas when first he came to live on the estate he could from a certain point see the spire only of a neighbouring church, he can now see the slates upon the roof. The sponge is being squeezed and drained, and rendered more compact. The half million tons of garbage which has been placed upon the surface must exercise considerable pressure and must serve to squeeze moisture into the deep trenches. Then, again, the upward drainage of the abundant crops is obviously very large indeed. The amount of moisture retained I20 CARRINGTON MOSS and evaporated by an acre of oats or mangold must be very great. There are, as yet, not many trees upon the estate, but part of it — about forty-three acres — is used as a nursery for the shrubs required for the parks and cemeteries of Manchester. These nurseries appeared to be most flourishing and contained a large variety of shrubs. The rhododendrons were extremely vigo- rous. Mr. McConnell assured me that the farm as a place of residence is by no means damp, and that the rain which falls upon his lawn quickly drains away to the reservoir beneath and leaves the surface dry. He and his family and the employes on the farm have always enjoyed excellent health. There has been one case of enteric fever in nine years, the cause of which is doubtful. Of the 1,100 acres of land occupied, 1,011 acres are let to tenants, and the rest is occupied by roads, wharves, plantations, &c. On July 30, 1900, I paid a second visit to Carrington Moss and I embodied the impressions made upon me in a letter to the Times ^ from which the following extracts are taken : " Let me say emphatically that Carrington is not a ' sewage farm.' The muck is dry, and is spread on the surface of the land and ploughed in in the ordinary way. There is no excess of water. Sewage farming in which the living humus is drowned by tons of water leads surely to agricultural bankruptcy. *' At my visit in 1898, and again in July of this year, I had ocular proof of the fertility of this reclaimed land. The hay harvest was just over, and had been a good one, and the standing crops of wheat and oats, potatoes and carrots, would be hard to beat in any part of England. The wheat was especially good, and one LAND SETTLING DOWN 121 field of 17 acres, which Mr. McConnell, the manager, estimated would yield over forty bushels to the acre, was certainly the finest I have ever seen. Much of the land is now passing into the hands of nurserymen and market gardeners. The ornamental shrubs (except conifers, which have no appetite for manure) were in splendid condition, and I am told that these nursery gardens are exceptionally brilliant when the rhodo- dendrons are in bloom. The physical change which has taken place in this bog as the result of the agricultural and other operations which have been carried out upon it is very interesting. The downward drainage by the deep trenches, and the upward drainage by the heavy crops, which to a large extent prevent the rain from percolating, have resulted in the sinking of the surface and the general compression of the bog so that the land tends steadily to get firmer. Formerly, when plough- ing, it was necessary to put ' pattens ' upon the horses' feet in order to prevent them from getting 'bogged,' but this necessity, I was informed, now seldom arises. " The farmhouse at Carrington stands on solid and deep foundations, but that the land around it is gradu- ally sinking is well shown by the fact that it is found necessary to provide an additional step for the door at recurring intervals. Between 1898 and my late visit a new step had been placed. At my visit in 1898 Mr. McConnell, who then occupied the farm at Carring- ton, gave an interesting demonstration of the character of the soil by driving an iron rod, 11^ feet long and half an inch in diameter, vertically through the turf of his lawn up to the handle. I easily did the same thing, for the rod having passed the first foot or so met with little resistance, and when withdrawn was found to be streaming with moisture. Mr. Carter, the present 122 CARRINGTON MOSS occupier of Carrington, kindly allowed me to repeat the experiment at my late visit. I managed with some difficulty to drive the rod into the soil for about 8 feet, but the increasing resistance prevented one from driving it completely *home.' When withdrawn, the rod was not wet, but was coated with moderately moist soil. The rapid desiccation and consolidation of the moss was thus made evident. *' I would respectfully suggest to the Corporation of Manchester that this great experiment merits systematic observation by men of science. A few ' surface ' wells for the periodic examination of the water by chemists and bacteriologists are much to be desired, and the changes of earth temperatures, the progressive altera- tions in the physical condition and the flora and fauna of the soil ought to be systematically recorded. *' The success attained at Carrington Moss has induced the Corporation to purchase some 2,500 acres of Chat Moss, which is now being subdued under the experi- enced guidance of Mr. McConnell, so that, eventually, the Corporation will be in possession of a fertile estate of 3,600 acres. Allowing 10 per cent, for roads and other works, they will have about 3,240 acres under cultivation, or land capable of producing annually 13,000 quarters of wheat and 8,000 tons of straw where none grew before. Assuming that the land is capable of receiving twenty tons of refuse per acre in perpetuo, the city will be in possession of a * destructor ' capable of consuming about 65,000 tons of organic refuse per annum, and each ton of refuse will ultimately return about a bushel and a half of wheat and 2^ cwt. of straw (the chief ingredients for 100 lb. of bread and perhaps 1,000 straw hats). " This, surely, is better than burning or fouling rivers. OUTLAY AND RETURN 123 This Manchester experiment should set us all thinking. Is there no possibility of bringing about a profitable interchange of produce between the great cities and the unreclaimed bogland of Ireland ? Is there not here a lesson for the consideration of every village council throughout the kingdom — a lesson which has been taught, not by the Utopian dreamer, but by hard- headed men of business ? " The accounts of the Cleansing Department of the city of Manchester for the year ending March 31, 1900, show that the Garrington estate yielded 777^. 55. Id, in excess of expenditure and that Chat Moss yielded an excess of revenue over expenditure amounting to 2,591^. 135. \d. The interest on loans (capital account) was for Carrington 2,036Z. and for Chat Moss 4,896Z., so that the net cost of these two estates amounted to 3,563^. \s, ^d. The amount of material sent to these estates in the year was 88,300 tons. I am well aware that in farming, where results de- pend so largely upon the weather, it is hazardous to calculate returns on the yield of a single year, and that anything under a ten years' average is likely to mislead. On the other hand, 10^. worth of produce from an acre of land is no excessive return. My visit to Carrington Moss left upon me the impression that much of the land is ready to pass, as some has already done, from the hands of the farmer to those of the market gardener. In that case, when oats, grass, and carrots and mangels give place to fruit and high-class vegetables, it is cer- tain that, with a market like Manchester at its door, the money value of the crops in Carrington Moss may be doubled or quadrupled. There is probably no city in the world where excreta are dealt with by methods other than water-carriage on so large a scale as they 124 CARRINGTON MOSS are dealt with in Manchester. In 1897 the city had an area of 12,911 acres ; it contained 534,299 inhabitants living in 105,728 dwelling-houses, or rather over five persons to a house. There were 76,913 pail-closets, presumably used by some 384,565 persons, who provided 189,585 tons (nearly 425,000,000 lb.) of ' pail contents.' It would appear from the Cleansing Committee's ac- counts (p. 36) that at the Holt Town Works 108,394 tons of *day soil' were converted into 6,304 tons of concentrated manure, and that for the production of this manure were used 4,897 tons of coal and coke and 1,674 tons of chemicals. Adding the weight of the chemicals to the weight of the ' day soil ' we arrive at the fact that 110,068 tons of raw material and chemi- cals were reduced to 6,304 tons by the aid of 4,897 tons of coal. Or we may say that 6,571 tons of fuel and chemicals produced 6,304 tons of manure from 108,394 tons of raw material. The amount of water and other volatile matter driven off amounted to 103,764 tons. The price paid for chemicals (5,098?.) and fuel (675Z.) amounted to 5,773Z., while the net profit on the sale of manure amounted to 2,081?. (p. 15). It is instructive to compare the Holt Town Works concentrated manure accounts (pp. 14-15) with the Car- rington Moss Farm accounts (pp. 28-31). At the former a turnover of 30,533?. resulted in a profit of 2,081Z., or rather more than 6J per cent., while at the latter a turnover of 6,202?. resulted in a profit of 1,041?., or very nearly 17 per cent. Turning to the City Trea- surer's Abstracts we find that whereas the Holt Town Works (p. 50), upon which the outlay has been 111,318?., are now valued at 71,429?., the Carrington Moss estate, upon which the outlay has been 82,946?., is now valued at 118,617?., so that while 39,889?. of capital have been lost at Holt Town, 35,671?. have been made at Carrington. CLEANLINESS OF GRONINGEN 125 CHAPTER XIV CONCLUSIONS I HAVE brought forward a considerable number of facts to prove that the dangers of applying dung to the soil are as nothing in comparison with the advantages— ad- vantages which have been acknowledged from the dawn of historic time till now. It remains to say a few words on the financial side of the question. The great experi- ment at Manchester seems to prove conclusively that even in a huge city and with the heavy outlay which seems to be inseparable from all modern municipal undertakings a well-considered scheme of application of offal and ordure m a dry state to the soil is the most economic way of getting rid of it. I have shown how in Holland great cities may be kept spotlessly clean and in spite of obvious difficulties the public health be main- tained by a well-devised system of scavenging. The cleanliness of Groningen is a thing which is scarcely realisable by one whose ideas of street sanitation are acquired in the West End of London, and the economy with which the scavenging is accomplished seems astounding to the London ratepayer. I have further shown that Holland, with a smaller area of cultivated land in proportion to population than England, is able to export to this country enormous quantities of farm and dairy produce, and that while the English farmer 126 CONCLUSIONS can scarcely exist the Dutch agriculturist thrives and grows rich. It will not be uninteresting, perhaps, if I give some of the results of my small experiment at Andover, which is now in its fourteenth year of trial. In this experiment the ordure and house refuse of about 100 persons have been removed and applied daily for gardening purposes. The amount under the spade is now exactly one acre, one rood, and seven poles, and I should like to say that the quantity of faecal matter at the disposal of ^my gardener by no means satisfies him. I am also convinced that the garden might take with advantage at least double the quantity if not more. There is no evidence, after a long experience, that the soil is overdone. On the contrary, its * condition ' has steadily improved. As to the financial results, the produce of my garden has been sold on the principle of profit-sharing, so that the gardener is interested in extracting the greatest amount of produce from the soil. During the past year (1889) careful accounts have been kept, and I find that the produce fetched l\l. 195. 6cZ., which works out to 56L per acre. Of this sum 41?. 125. Id, were received for fruit, and 30^ 65. \\d, for vegetables. Some of the chief items were as follow : Apples and pears, 18Z. 05. 6cZ. ; summer fruit, Yll, Is, Wd, ; peaches (outdoor), 3Z. 195. 2d5. ; potatoes, 6?. 35. 4cZ. ; cabbage and cauliflower, 5Z. I85. 3(i. ; tomatoes (outdoor), 2?. 35. ; asparagus, 2Z. I5. \d. ; and flowers, 2Z. 25. 5^. The method of agriculture which I pursue is well known, but this has caused no prejudice against the garden produce, which finds a very ready market. In the middle of my garden is a well, which affords evidence that no fgecal matters are washed downwards SHALLOW WELL 127 to the subsoil water. This well, which was made mainly for experimental purposes, is very shallow, little more than a dip-hole. The bottom is five and a half feet from the surface of the ground ; the sides are lined with concrete pipes to the very bottom, and around these four inches of concrete have been run in in order to give additional protection. There is a good parapet and a movable cover. The well was made in 1891, and the bottom and sides look as clean to-day as when they were made. No water can possibly enter this well except through the bottom, and I drink the water with- out any hesitation or misgiving because I know there are no leaking sewers or cesspools in the immediate vicinity. The only pollution this well gets is from insects, which creep under the cover. I value the movable cover because it gives me the power of inspec- tion, but I have not been able to keep the insects out. These are chiefly wood-lice and spiders. When it is remembered that the depth of water in the well is only three and a half feet (the water rises to within two feet of the surface of the ground), and the diameter two and a quarter feet, and that the quantity of water standing in the well is not more than some ninety gallons, it is obvious that a colony of wood-lice might easily affect an analysis. One day while removing the cover of the well, my gardener, before I could stop him, squashed some of the wood-lice which he found, between his thumb-nail and the inside of the cover. When the cover of this well is taken off on an autumn morning one finds much condensation on the inside of the lid. The water is vaporised by the heat of the day, and is condensed on the inside of the lid in the cold morning, and when the lid is taken off these condensed drops flow back into 128 CONCLUSIONS the well. The dead wood-lice on the lid became per- meated with fungi, and it cannot be but that the con- densed drippings took back the washings from the mouldy wood-lice. This interested me as showing how a well may, if left to itself, be in a sense self-polluting. Dead insects are of course capable of providing nourishment for countless bacteria, and the retrogres- sion of my well in bacterial purity finds, I think, a sufficient explanation from this cause. Last summer (1901) I kept a light cover of * scrim ' stretched on a hoop over the well. This kept out insects, but doubtless many minor impurities were washed through by rain. Then again the pump stands in the open, and of course affords a free passage to the well for many small things of the insect class. It is clear that no ground water can enter the well except through the bottom, but it has become equally clear to me that, having regard to the small capacity of the well, it is inadequately protected from minor pol- lutions of the class which I have described. These facts must be taken into consideration when reading the analyses. I wonder if bacteria of the coli group are found in wood-lice, spiders, and water-fleas ? I wonder what is the life history of a water-flea ? In the autumn of 1901 a sample of water from this well was analysed on behalf of the Eoyal Commission on Sewage Disposal, some members of the Commission having previously honoured my garden with an official visit. I have been favoured with a copy of this analysis, and it becomes of interest to compare analyses made at different dates. ANALYSES OF WELL WATER 129 The first analysis was made by the late Sir Edward Frankland in April 1892, who found (in 100,000 parts) : Organic nitrogen . 0-008 Nitrogen as nitrates and Ammonia . . none nitrites .... 0542 Chlorine . . . .1-9 The analysis for the Eoyal Commission on Sewage Disposal was made in November 1901. This analysis gives (parts per 100,000 by weight) : Ammoniacal nitrogen . 0-0002 Nitrate . . 0-68 Albuminoid nitrogen Nitrite . . 0-005 . none Combined chlorine . . 1-88 " This sample was clear and colourless, with a minute quantity of whitish sediment and one water-flea ; no smell ; alkaline." A " small duplicate, mercury -join ted and incubated at 80° F. on November 14, and analysed December 3," gave: Nitrite none Nitrate 0-69 The above analyses seem to me to show that the samples of 1892 and 1901 were for all practical pur- poses identical in quality. The slight increase of nitrates is probably due to the fact that the 1901 sample was taken in November, and the 1892 sample in April. The analysis of the Eoyal Commission gives certain other facts which the analysis of Sir E. Frankland did not give, viz. : Oxygen absorbed from permanganate at 80° F. — at once . . 0-01 Oxygen absorbed from permanganate at SO** F. — after four hours . 0-06 Oxygen absorbed from permanganate at 80° F. after incubation for five days— at once 0-02 Oxygen absorbed from permanganate at 80° F. after incubation for five days — after four hours 0*14 Dissolved oxygen (parts per 1,000 by volume) . . . .3-9 K I30 CONCLUSIONS Although we cannot compare the ' oxygen absorbed ' in 1901 and 1892, it may be advisable to quote from the reports on the quality of the London waters as given in the ' weekly returns of the Eegistrar-General.' Thus, in November 1901, Dr. Thorpe gives the * oxygen consumed ' in four hours at 80° F. (mean) by the water of the West Middlesex Company, which I have drunk for over thirty years, as -068, which exceeds the figure given by the Andover well. In January 1902 the average of the mean results for the West Middlesex water was -112. The other figures in the analysis of the West Middlesex water, so far as they are comparable with those of the Andover water, are : Nov. 1901 Jan. 1902 Organic nitrogen -017 -023 Nitrogen as nitrates and nitrites . . '167 -302 Chlorine 1-85 2-0 The water of the Kent Company, taken from a deep chalk well, is used as a standard of purity by the pre- sent official analyst (Dr. Thorpe), as it was by his pre- decessor (Sir E. Frankland). It becomes of interest therefore to state the facts (in so far as they are com- parable with the Andover water) of recent analyses. Det']^ Well of the Kent Company Nov. 1901 Jan. 1902 Organic nitrogen -009 '006 Nitrogen as nitrates and nitrites . . -439 -664 Chlorine 2-2 3-8 Oxygen consumed after four hours at 80° F.— mean -004 -003 The interesting facts in these last analyses are the fluctuations in the nitrates and nitrites and the chlorine. BACTERIOSCOPIC ANALYSIS 131 The analyses 1892 and 1901 of my well show not only that the water is one of fair quality, but they further show : 1. That the quality has not deteriorated in ten years. 2. That the faecal matter which has been freely placed upon the humus surrounding the well is all oxydised before it reaches the * ground water ' whence the well is supplied. The bacterioscopic analysis of this water, carried out by Dr. Houston for the Eoyal Commission, showed that one cubic centimetre of the water gave 1,400 bacteria on gelatine at 20° C, and 280 on agar at 37° G. Evidence of Bacillus coli (or closely allied forms) was obtainable from 1 c.c. but not from -1 c.c. The indol re- action was obtained from 1 c.c, but not from -1 c.c. The tests for Bacillus enteritidis sporogenes gave negative results. Dr. Houston adds a note to his analysis to the effect that " These samples were examined by the ordinary methods used in the bacteriological examination of sewage and sewage effluents. But in the bacterio- scopic examination of potable waters special measures should be adopted (for example the * Pasteur filtration method'). This procedure was not carried out in the present case. The negative results must therefore be interpreted as only implying relative, not absolute safety for drinking purposes. The presence of Bacillus coli in 1 c.c. points to animal pollution. Its absence from 0-1 c.c. shows that the contamination was not gross in amount." There has been an increase of bacteria in the water of this well since it was examined by Dr. Cartwright Wood in 1895. How far is this due to the circum- K 2 132 CONCLUSIONS stances alluded to above? Will spiders, wood-lice, earwigs, and water-fleas furnish bacteria of the coli group? This seems to me a question which must be answered. Except in the vacation I certainly do not visit Andover more than once a month. My experience leads me to say that it is to me almost inconceivable that the daily scavenging of our towns should not yield enough profit to pay the wages. It is especially to be noticed that the yield of this garden has under- gone steady increase, and I have every hope that such increase will continue. But it would be a great mis- take to suppose that an acre of ground, cultivated and manured as my garden is, is going to yield 50^. worth of produce per annum at once. The test of true garden- ing is increase. With the lapse of years, and without appreciable cost, the increase of fruit trees is automatic, and the yield of seeds is equally automatic and pro- digious. My garden has gradually become fully fur- nished, and to a large extent with its own offspring ; and in that fact lies part of the secret of its increasing yield. What we see in the London parks in the sum- mer is not * gardening ' but a beautiful display, after the manner of the houquetiere, of the results of garden- ing elsewhere. In the same way the filling of flower beds with a crowd of named and fashionable plants bought for the season is not gardening but a mere evidence of wealth. The real gardener in these cases is the nurseryman. The gradual increase in the yield of a plot of land, at least for a very long series of years, is limited only by the amount of skill and tillage which it receives and the amount of dung which is available for it. All evidence goes to show that organic manure in the BIOLOGY 133 form of dung is absolutely necessary for the main- tenance of the fertility of the soil. We are gradually becoming alive to the fact that fertility is a biological question rather than a chemical question. To imagine that chemicals can ever replace dung is a pure delusion from which we shall some day be aroused. The success or failure of agriculture is very largely a question of dung, and it must be admitted that the dung pro- spects in this country are very bad indeed. Imported animal food yields very little dung for the land because it is mostly washed (ultimately) into the sea, while steam-engines and motor cars and bicycles must mean a diminution of horse-dung. The sanitary pioneers of half a century ago thought that the huge expenses of modern sanitation would be compensated by the yield from sewage farms. That has proved to be a delusion. Sewage has proved to be merely the happy hunting ground of sanitary tradesmen who have fattened on the ratepayer. The nineteenth century closed with the spectacle of a Koyal Commission still discussing the best way of destroying the potentialities of life and prosperity. In these lectures I have brought forward many facts to show that there is no proof of any danger arising from the use of dung for agricultural purposes, while it is undeniable that the practice of agriculture is pre-eminently healthy and invigorating. I have been unable to find any evidence that contagia spread in the soil. To live in filth and to inhale the products of putrefaction given off from privies, or pails of faeces, or sodden ground, results in disease, but there is no evidence whatever that disease thus generated is able to spread through the soil and infect a neighbouring house or street. Looked at in another way we must admit that filth disease, like many other forms of 134 CONCLUSIONS disease, is proportionate to overcrowding. We may pave the backyard and provide it with a trapped gully (not always sweet) and we may wash the faeces into a ventilated sewer, which then delivers part of its vapours near our bedroom windows. It is a difficult problem, and there are pros and cons. While we exult (not always reasonably) in our diminished death-rate, let us not forget the diminished birth-rate, the multiplication of asylums of various kinds, and the steady increase in the amount of help from public funds which is necessary to maintain the health and decency of the masses. The year 1899 has been unsurpassed in the volume of trade and in the bounty of the harvest, but the infant mortality in our towns for the Michaelmas quarter was the highest on record. Yes ; there are pros and cons. At present he who advocates any attempt to entice a fair proportion of the people * back to the land ' is regarded as a Utopian dreamer. I feel convinced that the only chance of getting a living from agriculture lies in the due enrich- ment of the soil. There is no chance of this so long as the only form of sanitation which receives any official encouragement is one which involves a systematic starvation of the soil. One sometimes comes across statements which would lead one to suppose that cultivated land is a public danger — statements which are mere assertions. Some of our sanitarians, careless of food supply, are liable to be dominated by stereotyped ideas, and to fix their attention unduly upon one side of a question and upon one disease. The more enthusiastic of them, if they can secure a trifling diminution in the mortality of one disease, seem quite ready to * make a solitude and call it peace.' POLLUTION OF WATER SUPPLIES 135 , CHAPTER XV Entebic Feveb^ POLLUTION OF PUBLIC WATER-SUPPLIES : AT THE SOURCE, IN THE COURSE, AND AT THE PERIPHERY The Registrar-General's returns show that the death- rate from enteric fever, which was '322 in 1871-80, had fallen to -200 in 1881-90. Our satisfaction at this decline is seriously qualified by the fact that the tendency of towns to suffer from epidemics of the disease seems to be as great, if not greater than ever. At present (1898) there are three towns (Maidstone, King's Lynn, and Ligoniel, a suburb of Belfast) in which enteric exists in epidemic form as a result of the pollution of the public water-supply. Maidstone has had an amount of enteric fever in the last three months which, under ordinary circumstances, should have been spread over twenty-five or thirty years, and it is evident that this is a calamity of a kind which is not compensated by a decline in the endemic death-rate. I have collected for the purpose of this discussion short records of forty-six instances in which pollution of public water-supplies has taken place, resulting in outbreaks of enteric fever, more or * Being the opening address of a discussion on the subject of the Prevention of Enteric Fever, delivered before the Koyal Medical and Chirurgical Society, London, on November 23, 1898 (see also chapters xvi. to xviii.). 136 ENTERIC FEVER less severe. In thirty of these outbreaks the number of persons who suffered is given, and I find they amount to 16,576. I am, therefore, well within the mark when I say that for the last thirty years considerably more than 500 persons per annum have suffered from enteric fever as a result of the pollution of public water- supplies-. I am mainly indebted for my information to the reports made to the chief medical officer by the inspectors of the Local Government Board. These reports are among the chefs-d'oeuvre of English medical literature, and one hopes that they may be at some time re-edited and made more available, than at present is the case, to the great bulk of the profession. For six of the cases which I have tabulated I am indebted to the * Tabular Analysis of Water-borne Typhoid,' lately published by Mr. Ernest Hart. The contagion of enteric fever is contained in the excreta of the patient, and it is conveyed to the healthy person in his drink or in his food, and probably in the air he breathes. When enteric fever has occurred in epidemic form, the poison has usually been conveyed by water, often directly, and only less often indirectly, through milk or other beverages. In order to keep my remarks within bounds I shall not further allude to milk epidemics. The following is a brief tabular statement of the Contamination of Public Water-supplies, 1867-97 : Date Name of Town Source of Supply Where Polluted No. of Persons Attacked 1867 1870 1873 Guildford Warwick Sherborne Chalk well ? Wells Source and course ? Periphery 250 243 WATER-SUPPLY CONTAMINATION 137 Date Name of Town Source of Supply Where Polluted No. of Persons Attacked 1874 Lewes Wells Course 486 ,j Hull ? ,, 526 M Over Darwen )> ,, 2,035 1876 Tideswell M ♦» — 1878 Dewsbury l> Source and course 600 1879 Okehampton f) Periphery — M Swansea Upland Source 640 >> Caterham, &c. Chalk wells »> 352 1880 Enfield ? Periphery — >> Haverfordwest )) Course and Periphery — ,, Sandown Stream Source — >) Ventnor ? Course » Llanelly Stream Source — Perth River Course 162 >) Newlyn Well Source — 1881 Blackburn Course 238 „ Bodmin — Periphery — 1882 Bangor — Course 548 1883 Hitchin Well Source — 1884 Sheerness — Course — *) Kidderminster Well Course 1,200 »» Beverley Chalk well Source 231 1885 Faldingworth Well ,, — i> Fareham — Course and periphery 150 M Swansea Upland Source 549 1887 Margate Well '> — 1887-8 Mountain Ash — Course and periphery 518 1888 Buckingham — Course — 1889 Longton — ? 155 >) Eochester — Periphery — > Houghton -le- Spring Well Source 258 1890-93 Newark River jj 297 1890-91 Tees Valley >> )) 1,463 1891 Eotherham Strea.ms M 211 1891-2 King's Lynn M >> 226 1892-3 Chester-le- Street )) 58 1893 Atherstone '? Course 112 M Paisley Upland Source 672 >» Worthing, &c. Wells Source and course 1,411 1894 Newport » Source 516 1895 Raunds )> )) 129 1897 Maidstone Springs »> 1,890 )) King's Lynn Rivers >> 450 138 ENTERIC FEVER Of these forty-six instances of pollution of a public water-supply it will be noted that in three cases the water was polluted both at its source and in its course, and in three cases in its course and at the periphery. In twenty-one cases it was polluted at its source alone ; in twelve cases it was polluted in its course alone ; in six cases it was polluted at its periphery alone ; in four cases the fact is not stated. Of the twenty-one instances in which pollution occurred at the source it was shown that of such pol- luted sources eleven were wells, seven were streams and rivers, and three were upland sources. These streams and rivers had been polluted by the water-carried excrement flowing into them through the drains and sewers of places higher up, and in some few instances by the falling in of excremental matters from the banks or from boats and barges. Every river and stream in the country is more or less polluted in one or other of these fashions. This fact is too familiar to need further comment. The mode of pollution of the wells is of more im- portance. Three of these polluted wells are of a common type, e.g. at Newlyn, Faldingworth, and Eaunds, where the wells were polluted quite in the ordinary domestic way by the leakage into them, ftom neighbouring drains, of foul liquid, either from closets or washhouses where linen fouled by enteric had been washed. In the cases of Guildford, Caterham, Beverley, Hitchin, Margate, Worthing, and Newport, we have instances of the foul- ing of deep wells in the chalk. A deep chalk well is generally considered a safe source for water, and some appear to think that safety is proportionate to depth. It seems necessary to say that depth is no protection against the effects of leakage at any point, for leakings DEEP WELLS 139 must fall to the bottom. It is necessary also to say that the difficulties of inspection are very largely propor- tionate to the depth. Again, as leakage may occur at any point in the walls, the area of the walls is in some sense a measure of the vulnerability of the well. The chemist and bacteriologist may report with regard to a particular sample taken at a particular time that the water is * of excellent dietetic quality, well suited for the supply of a town,' but the merest tyro in well-sinking might point out the dangerous position and formation of the well. With regard to these wells the following particulars may be given : 1. At Guildford the pollution of a new chalk well was caused by the leakage into it of quantities of sewage from an old ill-constructed sewer. 2. At Gaterham an adit over 400 feet below the surface was definitely fouled by a workman suffering from enteric, who deposited his evacuations in the tunnel. The investigation of this classic case was carried out with remarkable acumen by Sir Eichard Thorne. The following are the facts : 1879. Bed Hill and Gaterham (Dr. Thorne Thorne). — 352 cases caused by a labourer who was working in the adit of the water company, and who was suffering from enteric at the time, actually depositing his evacuations in the tunnel. The evidence shows that he began to be ill on January 5, and that he continued to work in the adit until the evening of January 20, when he was too ill to continue. The adit was therefore possibly fouled with enteric evacuations for sixteen days, and possibly in increasing amounts. The epidemic began on January 19, and, reaching its climax on February 1, came to an end about a month later. I40 ENTERIC FEVER Although I think that Sir Eichard Thorne clearly demonstrated the true source of the enteric contamina- tion, it was nevertheless shown that the Caterham wells (three in number, sunk for some 400 or 500 feet through clayey gravel and chalk, and with borings going to a greater depth) were seriously liable to contamination through fissures. Thus on one occasion " waste water was pumped into a hollow spot about 170 feet to the east of the wells ; here it disappeared, but it was soon ascertained to be returning into the wells at a depth of 420 feet." The formation in which the wells were sunk was, indeed, dangerously fissured in all directions, and there were cesspools at various spots round the works. 3. At Beverley the well (333 feet deep) was alongside a sewage farm belonging to the East Riding Asylum, and from an irrigated field sewage is supposed to have trickled down the well shaft. Here we have an instance of sanitary works carried out for the benefit of one community causing serious trouble to their neighbours ; and other instances of this have occurred. 4. At Hitchin we are told that defects in the water- works permitted occasional back-flow of sewage-polluted river water into the pumping well. 5. At Margate the well was exposed to contamination by soakage from sea water and from cesspools. 6. At Worthing we have a leakage of a sewer into a heading run from the bottom of a deep chalk well. 7. At Newport (Isle of Wight) the chalk wells were fouled by an adjacent pond, and probably by more distant leaking cesspools, of which there were many. This water contained the Bacillus coli, and I trust we may learn in this discussion what is the true value of that fact. The eighth case of the fouling of a deep well occurred POLLUTION OF WELLS 141 at Herrington, near Hough ton-le- Spring, and the follow- ing are the facts : 1889. Houghton-U'Spring (Dr. David Page).— 258 cases occurring in a population of 4,400 situated within the area of the Herrington water-supply. The supply was from a well 330 feet deep, through * clay with sand partings in seams ' (72 feet) ; limestone marl (15 feet) ; and for the rest through sandstone and shale. The sides were lined with bricks set in mortar, and it was believed to be impervious. On examination the sides of the well were defective, and a * feeder ' was found discharging into the well 45 feet below the surface. Microscopic examination of this water afforded evidence of contamination with household refuse, and the source of contamination proved to be a farmhouse containing a water-closet, situated three-quarters of a mile off, and draining into the well through a fissure in the magnesian limestone caused by the subsidence of a colliery beneath. On examination the pipes of the Herrington service were found excellently jointed, but the sewer pipes were leaking. This case is one of very great importance. The water company here was free from blame ; the pollution was due to what may be called a pure accident. It is well to call attention to this case, because the deep tunnelling which is going on, and which is being proposed, in London may not be without its effects upon the network of pipes above. These facts lead one to make a few remarks as to sources of water. Enteric fever being essentially a human disease, the chances of getting water impregnated with enteric at its source must bear direct ratio to the 142 ENTERIC FEVER density of population round that source. On that account there is just now a rush for gathering grounds which are uninhabited. Some of these moorland waters are not without their disadvantages, and we know very little as to the comparative receptivity for poison in hard or soft waters in the presence of enteric excreta. In the above list there are three instances (Swansea [2] and Paisley) of contamination of upland waters. I find in Glasgow, which enjoys an unlimited supply of the purest water in the world, that in the ten years 1881-90 the enteric fever death-rate was -25 per 1,000 living. The enteric death-rate for 1881-90 for England and Wales was -20, and for London -19. The figures seem to show that Glasgow, in spite of its pure water, enjoys no immunity from enteric fever. With regard to the relative advantages of wells and springs (captured and enclosed) as against rivers, there are certain obvious facts which must not be forgotten. If a well or spring be fouled, the whole of the fouling is mixed with the water and supplied to the houses. There is, so to say, no escape for accidental pollution except into the water-pipes. Given the fact of fouling, wells and springs are likely to deliver a dangerous dose. A well, in this respect, is analogous to the ' dead end ' of a water main, which is always a dangerous spot in case of fouling. If a river be fouled, more or less floats away or passes by the intake. I need hardly allude to the obvious fact that the water in a river is exposed to fresh air and sunlight, while the water in a well enjoys no such advantage. There were eighteen cases in which a public water- supply was polluted in its course, that is, in its transit between the source and the houses, viz. at Guildford, Tideswell, Dewsbury, Haverfordwest, Ventnor, Black- LEAKING SEWER-PIPES 143 burn, Bangor, Sheerness, Kidderminster, Mountain Ash, Lewes, Hull, Over Darwen, Perth, Fareham, Bucking- ham, Atherstone, and Worthing. Of these eighteen cases, one (Bangor) was caused by fouling of the filter- beds, and two (Haverfordwest and Ventnor) were due to fouling of the reservoirs. The other fifteen were practi- cally due to the same cause, viz. tlie in-suction of foul air or liquids by leaking water-pipes during inter- missions in the supply. It is not necessary to go into details of these cases, but it may be stated that at Guildford a sewer was actually traversed by a water- pipe, and at Sheerness * water mains were often laid in the same trench as tributary sewers.' At Perth river water from near the sewer outflow got into the water main which runs under the Tay. We must remember that sewer-pipes and water-pipes, however well laid and made, are like ourselves mortal, and liable to accidents and the inevitable results of age. They are perfectly sure to leak sooner or later from some cause or another. If they leak we must reckon upon an interchange of their contents. These pipes are always placed in proximity to each other and out of sight, so that if the sewers leak into the water-pipes our first indication of it is an outbreak of disease. I have a cottage in the Thames valley where the Local Council, by the help of some 130,000/. borrowed with the consent and implied approval of the Local Government Board, is and has been busy, by dint of sewering and paving all the country roads, in making the way smooth for the speculative builder and site owner, who fill their pockets by building houses with the minimum curtilage allowed by the Local Government Board. The houses are springing up at a rate of twenty- five or thirty to the acre, and at a rent of about eight 144 ENTERIC FEVER shillings a week. I see the water-pipes and sewer-pipes being laid for this mushroom crop of brick and stucco, and in the mornings I hear the traction engine and steam roller rumbling about only a few feet above these pipes, as though their only thought was to make quite sure of cracking them. I may recall the fact that a few years ago in London the local authorities, by removing every particle of snow and throwing down salt, succeeded in surrounding our water-pipes with a freezing mixture, with the result that no small proportion of them burst ; and I may also recall the fact that a deep tunnel caused a dangerous subsidence of the earth above it only a few weeks ago in the City. The only way of minimising the very obvious danger of thus laying water-pipes and sewer-pipes would be to insist that where they go together they shall do so only in subways, where they are open at all times to ready inspection. An alternative would be to insist on maintaining narrow roadways between the backs of new houses, and to keep the sewers at the back and the water-pipes in the front. Whatever plan be adopted, it is evident that these two sets of pipes — afferent and efferent— must come into close proximity somewhere. Nevertheless what I have suggested would lessen this danger. Next I have to say a few words on the very important subject of the pollution of water at the periphery, i.e. through the taps. This mode of pollution has been, I think, most con- clusively established. One of the first persons to call attention to this danger was Dr. Blaxall, in a report on an outbreak of enteric fever at Sherborne. This was followed in a few months by the late Sir George Buchanan's report on MOUNTAIN ASH EPIDEMIC 145 Caius College, which must remain for all time one of the classics in the literature of preventive medicine. Mr. Spear in his report on Mountain Ash, Glamorgan, deals with the same point. I will quote from these three reports, but I think we shall derive most instruction by reversing the order and taking Mr. Spear's first. 1888. Mountain Ash (Mr. John Spear).— The 518 cases of this epidemic were chiefly due to the in-suction of foul air (and liquids and solids ?) into water-pipes during intermissions of supply. Leakages in the pipes were numerous. There was some evidence to show that streets supplied with water-pipes having ' dead ends ' suffered somewhat more than others. Concerning one of these terminal * dead end ' branches Mr. Spear says, " It would take its full share of the first rush of water (after an inter- mission), and all impurities would have to be withdrawn through the house taps." In another place he says, ** Given a fever poison present in a water system, it is quite possible that in the dead ends of pipes or at other places where stagna- tion occurs, or at any given point where escape may take place into the soil, further development of the poison leading to new or more intense infection of the water may occur." Allusion is made to a dead-end pipe, fifty-three yards long, gradually ascending from a larger main to supply a school, including two closets which were supplied by pipes direct from the main, " When the water was turned off at the main, and the tap of one of these closets opened for a moment, suction of air up the pipe was immediately heard." Mr. Spear further adds in a footnote, '' Suction into this main was very strong during intermission of service. At such times the house taps 146 ENTERIC FEVER greedily sucked up water placed at their open mouths." It wants only a moment's consideration to see that ascending * dead ends,' whether in houses or in streets, are converted into powerful aspirators directly pressure within them fails. In the school above mentioned there were two cases of enteric, and it is possible that specifically infected matter had been aspirated into the mains. In another part of his report Mr. Spear has this im- portant paragraph : — *' Intermission of water-current, however, is not by any means essential to the introduc- tion of foreign matters into water-pipes. Under various physical conditions very powerful in-suction of external matters into a full-flowing water-pipe can take place . . . But the fact of this lateral in-suction into water-pipes * running full ' is not known, as it ought to be, to many of the engineers who undertake the responsible business of laying water mains and other water-pipes." 1873. Gaius College (Dr. Buchanan). — 15 cases, of which 12 occurred in * Tree Court,' which had been built only a few years and contained all the latest 'sanitary improvements.' Out of 63 residents in Tree Court, 12 (or 19 per cent.) were stricken with fever in the month of November. Tree Court had a water-supply through a branch from the main in the street, which, to use a pathological expression, was an * end artery,' and, although it supplied a branch to each of the nine staircases of Tree Court, formed no anastomoses with any other water-pipes in the college. This water got fouled by one of two private closets in Tree Court. The manner of the fouling was in this way. The closet which was on the first floor of staircase P was provided with a * safe,' i.e. a big metal tray sur- rounding the base of the closet to catch accidental CAWS COLLEGE EPIDEMIC 147 splashings and drippings. This * safe ' drained into the soil-pipe just beyond the closet- trap, through a small pipe with a trap of its own. The subsidiary trap was fed by what is technically known as a weeping-pipe, a branch of the pipe supplying the closet. This closet supply was direct from the Tree Court main without the intervention of any cistern. The water-supply to Caius College is * continuous,' but it is liable to intermissions, and such intermissions are known to have occurred on October 25 and Novem- ber 1, and probably at other times. When, with the water turned off, the closet on stair- case P was used, the trap of the safe would be emptied and the trap of the closet be left filled more or less with faeces. The weeping-pipe was therefore open to the sewer air coming up the soil-pipe and to the filth in the closet trap. With the pipes of Tree Court empty of water they would be liable to be filled with sewer air. It was further proved that the end of the weeping-pipe was covered with filth, and it is probable that the water system of Tree Court was definitely inoculated with Bacillus typhosus in addition to being impregnated with sewer air. 1873. Sherborne (Dr. Blaxall).— 243 cases. * Board of Health ' water derived from two deep wells. Water- closets supplied direct from the mains. Between De- cember, 1872, and May, 1873, there were 243 cases. " During December, 1872, and January, 1873, the water was frequently shut off from the town at a point near to the reservoir, and the same thing was done every night in February. It is known that when the water was thus shut off there were certain delivery pipes up which there was a rush of air immediately the tap was unscrewed. Now many of the openings of the pipes, as before L 2 148 ENTERIC FEVER described, are situated in the pans of the water-closets. At night, after the closet had been used, the tap would be turned on for the admission of water ; none flowing, the tap in many instances would not be turned off again, and thus a direct passage into the water mains would be left open. . . . Thus the system of pipes for the water- supply became the means of ventilating the closet pans ; if a trap happened to be broken or out of order it became a means of ventilating the sewers, and if a pan happened to be full of excrement that excrement would be sucked into the water-pipe." This mode of water pollution is well understood, and we know the importance of maintaining constant pres- sure in our water service. It seems clear that many of the critics of Maidstone have not been aware of the danger of lessening water pressure at a time when the sewer-pipes must have been highly charged with enteric poison. How far is the maintenance of constant pressure attainable? It is evident that there must arise occa- sions when the water-pipes must be empty. To main- tain constant pressure is a counsel of perfection which is unattainable. The dangers of peripheral pollution, by the in- suction or diffusion of foul gas or liquid, is so well recognised that all w.c.'s are now supplied through independent cisterns. There is yet another way in which peripheral pollu- tion of a public water-supply may take place. The outbreak at Worthing in 1893 was accompanied by an outbreak in the adjoining districts of West Tarring and West Worthing having a different water-supply, and the explanation of this is that Worthing water entered the pipes of the adjoining districts through the ball STORM EFFECTS ON SEWERS 149 hydrants in the street at a time when the pressure in the pipes intermitted. A few weeks before the close of the last holidays I was staying at Andover, which has a mmiicipal water- supply obtained from a deep chalk well. During one of the last days of September there was a very heavy thunderstorm with torrents of rain. I went out in this storm to one of the lowest points in the town, and there I found what I had found before under similar circum- stances, viz. the water bursting up through the street sewer, with the result that the street was flooded with foul water and faecal matter. A few inches below this mess were the water-pipes supplying the district, and I hope they were not cracked, and that the pressure in them was fully maintained until after this impregnating flood had subsided. I stood at the lowest point to which storm water must gravitate, and here Nature had provided an over- flow into a ditch. Some years ago the storm water was taken into the sewer, and a storm overflow from the sewer was taken into the ditch. Nature meant that the sudden storm should cleanse the surface of the ground and also cleanse the ditch, and thus do nothing but good. Man interfered, with the result that, instead of being cleansed, both the street and the ditch were filled with the poisonous purgings of a sewer. I give this as a type of what is common. The craze for taking rain water underground instead of allowing it to run on the surface is as dangerous as it is costly. The experiences at Sherborne, Mountain Ash, and Caius College seem to point to the conclusion that every public water-supply should protect its own purity, by compelling every house to have a cistern of its own as a * cut-off ' between the impurities of the house and the I50 ENTERIC FEVER water in the mains. This necessity is implied by the compulsion which we are now under of having a separate cistern for the water-closets. But water-closets are not the only filthy places. There are water-taps which are theoretically capable of tainting the water-pipes under certain given conditions almost everywhere. Most * noxious trades ' require water. Kitchen sinks are not always sweet ; the post-mortem room sink is an uncom- fortable thing to think of in connection with peripheral pollution, and bacteriological laboratories fill us with 'horrible imaginings.' Sewer air is everywhere, over street gratings, and at the eaves, and although diluted almost to vanishing point, it makes up by quantity what it may lack in intensity. In Dr. Thresh's valuable book on * Water-supplies,' p. 211, I find an allusion to an observation by Sir G. Buchanan at Croydon in 1875, of an instance in which bloody water was drawn from a tap at a house next door to a slaughter-house. This is a fact which is very eloquent in connection with automatic peripheral pollu- tion. Under existing conditions it appears certain that every common water-supply is to a greater or less extent automatically self-polluting, and it will be interesting to hear what the sanitary officials may have to say on this question of the house-cistern as a 'protection to tine general supply. A dirty house-cistern is doubtless very undesirable for the people in the house. If it is dirty, that is their fault, and it seems unreasonable that the purity of the general supply should be endangered by the filthiness or carelessness of the householder. That the filthy should * stew in their own gravy ' is reasonable enough, but that the cleanly should be called upon to stew in it is unreasonable. WATER SUPPLY 151 CHAPTEE XVI RECOMMENDATIONS AS TO WATER-SUPPLY— WHAT TO DO WITH INFECTED MATERIAL— TREATMENT OF INFECTED LINEN -DISPOSAL OF EXCRETA— HIS- TORICAL, « The remarks which I have made on public water- supplies seem to show that when we accept a water- supply from a public body, our health to a considerable extent passes out of our own keeping. That is obvious ; and it is also obvious that when the order is given to close a private well, and to accept a public supply, the sanitary authority incurs a very grave responsibility indeed. The instances I have quoted seem to compel the conclusion that public water-supplies are a cause of the epidemicity of enteric fever. These water-supplies diffuse the poison with a completeness which is almost inconceivable, and further insure that the poison is laid on, as it were, to our very mouths. The condition of a city with its water-supply polluted by enteric is fearful to contemplate. Not only is the water being drunk, but the inhabitants are washing in it, the dairies and milk cans are being swilled with it, the very pats of * margarine ' are being made up with its help, the oysters are lying in it, the salads and flowers are being sprinkled with it, and the streets are being watered with it. Then when the need 152 ENTERIC FEVER of closet-flushing is at its maximum, and the street sewers are full of enteric poison, comes the order to cut off the water, and it certainly requires great skill to minimise the danger of so doing. These epidemics show the danger of * putting too many eggs in one basket,' and they force upon us the necessity of arranging water-supplies with as many independent sub-divisions as may be feasible. They also serve to show the necessity of not permitting the mixing of water derived from different sources. Dairy companies have learnt, by bitter experience, the neces- sity of keeping the milk supply from different farms absolutely distinct. Water companies must do the same thing. The great milk companies have voluntarily adopted a system of milk supervision which approaches perfec- tion. The milk is submitted to a daily, almost hourly, examination by skilled experts. The water companies must do the same thing. Every water company ought to have a laboratory for the chemical and bacteriological examination of the water which it distributes, and there ought to be a proper staff of skilled experts constantly at work examining samples taken daily, or even hourly, not only at the source, but at various points in the area of distribution. Under existing conditions the purity of our water- supplies can only be maintained by vigilance and publicity. The notification of disease is undoubtedly a great protection, but it is clear that every notification should he forwarded instantly to the water authority and the sewer authority ^ whose respective inspectors should examine the implicated premises without delay. It is evident that repeated chemical and bacterio- SHALLOW WELLS 153 logical examinations of water are of great value, but it is not probable that they are much protection against sudden pollutions occurring after heavy downpours of rain. The mischief is done suddenly, and both the chemist and bacteriologist will possibly be able to register the catastrophe, but not prevent it. It is most important that the public should not be led to expect the impossible, and to imagine that analyses can make a public water-supply secure. The interpretation of analyses is not always easy, but any sudden change in the quality of a water would arouse suspicions. Of what import is the presence of Bacillus coli in a water ? This bacillus is known to occur in rabbits and birds. Does it occur in the dung or dead bodies of insects, such as spiders, centipedes, slugs, snails, &c., which are very apt to gain an entrance into wells ? Does it occur in fish? This question ought to be answered. All sources of water not only need to be guarded by chemists and bacteriologists, but they need constant watching by a shrewd practical man. It is not too much to say that all sources of water have their purity endangered by sudden flood and downpours, and water- collection should be as far as possible stopped during such occurrences. A clear water which suddenly becomes turbid must always be dangerous. My shallow well at Andover, which is only five feet deep, and which is absolutely protected from surface or lateral con- tamination, has once or twice become turbid after exceptionally heavy rains. The reason for this appears, to be that so soon as the soil above the ground water gets saturated, the deposit on the bottom of the well is driven upwards by the suddenly increased pressure under which the water rises in the well. IS4 ENTERIC FEVER There is very definite safety in having the water sources near at hand and capable of being inspected. By means of the electric light a well of moderate depth can easily be inspected, but it is difficult to know what may have happened in a bore-hole at a depth of 400 or 500 feet. There are some who are of opinion that the public safety would be enhanced by placing our water-supplies in the hands of public authorities ; I am not of this opinion, for the following reasons : 1. Because private authorities can control their servants and get rid of incompetent officers more easily and promptly than public bodies, who are elected to their offices by their servants and the friends of their servants. 2. Because water companies equally with railway companies should be made liable to ' damages ' in case of accidents. A successful action for damages against a sanitary authority by, let us say, 10 per cent, of the ratepayers of a town would result in the payment by the plaintiffs of 10 per cent, of the damages awarded them, while the bulk of the remainder would be paid by persons who are blameless and helpless. This is a reductio ad absurdum, 3. Because no person should be allowed to control a water company without incurring some degree of personal responsibility. It is the power of borrowing and spending money without personal responsibility that constitutes the dangerous element in our modern local government. I am very strongly of opinion that water companies should be placed exactly on the same footing as other trading companies, and that every householder should have the right of paying for water by meter if he so WASTE OF WATER 155 desires. In houses not supplied by meter no waste- pipe should be allowed beneath any supply tap so as to insure that, if the tap be left carelessly turned on, the house must be flooded. This would effectually check waste. It seems very necessary to check waste of water. Many local authorities are at their wits' end for water, and are calling in the help of wizards. But we have had the comforting assurance that this, at least, is a form of sanitary quackery which the public auditors do not allow to be paid for out of the rates. Wilful or careless waste of water (as by leaving a tap turned on) should be punished by fine when water is not paid for by meter. Waste of water often necessitates the severe pumping of wells and other sources, which increases the danger of pollution. Waste must be checked. There are others who seem to think that we shall attain greater safety by the registration of plumbers. These sanitary scapegoats are, I think, more sinned against than sinning, and are often blamed most unde- servedly for the inherent shortcomings of our modern sanitary methods. If, however, plumbers are to be registered, it does seem desirable that they should be divided into two classes, and that we should run no risk of allowing a man to attend to the water service who perhaps carries about him infective matter acci- dentally picked up in the * drains.' The Disinfection of Linen At University College Hospital some years ago this question was submitted to a small committee, of which I was a member, and we advised as follows : 1. That the linen should not be treated with 156 ENTERIC FEVER carbolic acid or corrosive sublimate, because of the fear of coagulating albuminous soilings, and for the same reason that it should not be put at once into boiling water. 2. We advised that a special tank should be provided, and should be filled every day with cold water to which washing soda is added (about two pounds to a hundred gallons) ; into this tank the soiled linen is taken directly from the wards, and is allowed to soak till the following morning, when the water in the tank is thoroughly boiled for one and a half hours, and after boiling is run off into the sewer. In this way the first stage of the laundry work is accomplished. The efiiuent water is sterilised, as is also the linen. The same process can easily be carried out in private on a smaller scale. Disinfection of Stools We now come to the important question as to what ought to be done with the stools of enteric patients. I have no hesitation in saying that in towns at least they should be hurnt or boiled, and in all fever hospitals intended for the reception of this class of patients a proper destructor should be provided. I have very little doubt that if this be accepted as a principle, human ingenuity will soon provide the means. It is most desirable that, in the interest of the nurses and friends, there should be a minimum of manipulation of enteric faeces. I have my own ideas as to how this end may be accomplished, but I must limit myself to the discussion of principles rather than details. I have very little faith in chemical disinfec- tion. Badly done, this is more likely to preserve than ENTERIC EXCRETA AND WATER 157 destroy the poison, and the amount of manipulation which thorough chemical disinfection necessitates is most undesirable. Of one thing I am convinced, and it is this, that under no circumstances whatever should enteric excreta he mixed with water. We know how insidious this mixture is, and that the danger of it practically increases when dilution has been carried to the extent that the mixture has, to our unaided senses, the characters of potable water. Enteric fever is pre- eminently a water-borne disease. Enteric stools, there- fore, must not be mixed with water, because it is the property of water to return to its source. * All things that are of the earth turn to the earth again, And aU things that are of the waters return into the sea.' Ecclus. xl. 11. Let me illustrate this by some examples. A stool mixed with water flows to the sewer, and so directly to the sea. One would suppose that a stool so treated was safely disposed of. Not at all ; the enteric poison returns to us upon the oyster, and it must be admitted that our habit of mixing enteric stools with water is in a fair way to destroy our oyster industries —the fame of which extends to the extreme limits of our historic record. A very eminent agriculturist has said that our sewage is good for our fisheries. At present we have very conclusive evidence of evil, and no evidence of good of any kind. Again, an enteric stool mixed with water flows to the sewer, and from the sewer leaks into a deep chalk well, as at Guildford and Worthing, or runs off the surface of a sewage farm into a deep w^ll, as at Beverley, whence it is pumped in a state of extreme subdivision to poison 158 ENTERIC FEVER others. Or the mixture runs to the sewer, and so to the river, passing en route through the watercress beds. From the river it is pumped to the consumer of water, and the watercress is sent far and wide, mainly to our operatives in the big towns. The watercress industry, like the oyster industry, is endangered, and we may soon be deprived of this most agreeable vegetable. Or the mixture runs to the sewer or cesspool, and leaking, under pressure, worms its way sooner or later to a well or spring, and possibly finds its way to the milk. Or the water leaking from the sewer flows into the leaking water-pipe, and so back to the consumer. Lastly, as at Caius College, the mixture may be sucked directly from the water-closet into the pipe supplying the drinking- water. Water returns to its source, whether the circuit be long or short. If any underground receptacle for water or sewage begins to leak, and if the water in such receptacle be constantly renewed, there is no limit to the distance whether laterally or vertically which it may not travel. The danger of a constant drip of water on one spot is proverbial. It is a very serious danger in relation to our water-supply. The deeper it goes, the further it is likely to go. The pressure of a column of water is, roughly speaking, nearly equal to half a pound for each foot of vertical height. The force with which the water returned from the surface into the Caterham well was, at its maximum, about 185 lb. to the square inch. What has just been said is founded on facts which are familiar to everybody, and which are of almost daily occurrence, and in this discussion it is most essential to keep fact and theory quite distinct. The familiar accidents to which I have just alluded are due entirely SIR WILLIAM /ENNER 159 to the fact that enteric stools have been mixed with water. There can be no doubt but that enteric fever must have existed from all time, and that stools must often have accidentally found their way to a spring or other water source, but I think there is small room to doubt that the great cause of the increase and wide epidemicity of enteric fever in modern times has been the water-closet. It is now half a century ago (in 1849) that my great master. Sir William Jenner, contributed to this Society a paper which closed the controversy which had been raging for some ten years previously on the iden- tity or non-identity of typhus and typhoid fevers. The distinction between them is so clear that we of to-day can hardly understand the controversy. It has been like a dissolving view ; the clearly focussed typhus of 1830 became obscured by new elements, which have gradually entirely occupied the screen, till now we have nothing but the distinct features of enteric, and typhus has vanished. It seems probable that the main cause of the vanish- ing of typhus was the repeal of the Corn Laws in 1846, and the better wages and cheaper food which our industrial population has enjoyed in increasing degree. On the other hand, the rise of enteric was probably due to the invention of the water-closet and the gradual introduction of water-carried sewage. It must be re- membered that the year 1849, in which the non-identity of typhus and enteric was settled, was the year in which cholera was raging, the year in which the great fact of water-borne disease was established. The conditions which gave us the great outburst of cholera in 1849, when the Thames between the bridges was at once our cesspool and our source of water, were i6o ENTERIC FEVER eminently calculated to furnish sufficient enteric fever for the establishment of its identity. If the same conditions had obtained in the days of Heberden or Mead, Syden- ham or Morton, the identity of these fevers would have been established one or two centuries before. So glaring a fact could not have escaped these most acute observers. The sanitary methods of our ancestors were simpler than ours. Water was pumped from a well on the premises, excrement was deposited in a dry privy and removed once a year by the nightman, while the slops — trivial in amount as compared with the present day, and containing no specific poisons — ran to a dead well or sump, or flowed in an open channel to the nearest stream. The old-fashioned privy, if kept scrupulously dry and if the vault was ventilated, was by no means so offensive as is the cesspool. The smell was sui generis. The privy was generally well removed from the house ; sometimes was big enough to accommodate three people at once ; was furnished with a special seat for children (a most excel- lent arrangement), and sometimes had a courtyard of its own. There was no sloppiness or putrefaction and not much or any soakage, especially if the vault was ventilated so as to allow of evaporation. When this arrangement was carried out with a fair amount of common sense and with sufficient space the surface-well ran little risk of infection by specific poisons. Water being unobtainable without the labour of pump- ing, there was no waste, and allowance being made for evaporation, the volume of slop -water must always have been less than the volume pumped from the subsoil. This appears to me to be a not unimportant fact, and it is evident that the soil round the dwelling ran less risk of getting waterlogged and sour than is the case where unlimited water is poured into the premises of thriftless WATER-CLOSETS i6i and careless people, who are incessantly pouring slops into a subsoil from which they are forbidden to pump. When the water-closet was introduced, and its contents were shot into the previously dry privy, putre- faction resulted. * Sewer gas ' was invented, and the privy began to leak under pressure, to the imminent danger of the well. The privy was, by the use of the water-closet, converted into a cesspool. As late (I quote Mr. Lewis Angell) as 1815 it was penal to discharge house drainage into sewers. Chief Justice Holt laid it down " that every man should keep his dirt to himself." The water-closets and the resulting cesspools necessi- tated first the admission of the overflow from cesspools into the sewers, and then about 1848 some 30,000 cess- pools were abolished in London, and the houses drained directly into the sewers and so to the Thames. We have had cholera in 1832, 1849, 1854, and 1866 ; the death-rate from diarrhoea, which in London was -215 in 1838, rose to 1*705 in 1849. As a direct consequence of the legislation of 1848, every river and every source of water in the country became polluted or in danger of pollution. We then passed a law forbidding the pollution of rivers. Dr. William Farr fully recognised that the cholera of 1849 and 1854, and the increase of diarrhoea, were due to the water-closet, but he still hoped that the con- tents of a machine which rids our houses of filth need not necessarily poison our rivers and other sources of water. I confess I am very pessimistic on this head, as will be gathered from my remarks on the property of water to return to its source ; and I feel convinced that unless we are guided by sound principles, all expenditure with M 1 62 ENTERIC FEVER a view to the prevention of enteric fever will be wasted. In the account of almost every outburst of enteric fever one comes to the inevitable mixture (generally deliberate and intentional, but sometimes accidental) of faeces and water, and in a large majority of such cases we find the water-closet. There are some who seem to think that the abolition of middens and cesspools and their re- placement by the underground sewer will abolish enteric. I cannot share any such belief, because it has been shown again and again that the leaking sewer or drain is quite as much a danger as the leaking cesspool, and water leaking from the same spot may (as I have shown) trickle any distance. A drain made of so-called sanitary pipes has a potentiality for leaking at some 1,760 joints in every mile of length. Every town or village which has underground sewers will certainly, sooner or later, poison its local wells and other sources of water. Whether or no we are able to obtain pure water depends entirely upon our treatment of putrescible refuse. If this be put beneath the surface of the ground instead of upon it, the danger to every source of water is immense. APPENDIX With reference to the Bacterial Treatment of London Sewage, the reader is referred to the summaries of the Eeports by Dr. Clowes and Dr. Houston to the London County Council in the ' British Medical Journal ' of January 12, 1901, p. 104, and of February 2, 1901, p. 287. Briefly Dr. Clowes, dealing with the general and chemical aspects of the matter, concluded : (1) That the effluents from the great mass of London BACTERIA IN SEWAGE 163 sewage, clarified by screening, precipitation, and sedimentation, may still lead to serious foulness of the river, containing as they do a large amount of putrescible matter. (2) That in summer-time, when the flush of water from the upper river is diminished by drought and by the abstraction of larger volumes of the water by the water companies, the condition of portions of the lower river frequently closely approaches that necessary to cause offence. Fortunately the results of the long experiments carried on so systematically since 1893 indicate that the London sewage may be so far purified by means of contact beds, that a clear, non-putrescible effluent may be obtained far purer than the effluent at present obtained by precipitation and sedimentation. The introduction of such a sewage effluent, clarified and freed from most of the organic matter, into the muddy and brackish waters of the lower Thames may be effected without giving rise to any offence. On the other hand Dr. Houston, working at the bacteriological aspect, found as the result of a very large number of experiments that the total number of bacteria, the number of spores of aerobic bacteria, the number of liquefying microbes, the numbers of Bacillus coli and of spores of Bacillus enteritidis sporogenes were not remarkably less in the efifluents from the coke beds than in the corresponding samples of crude sewage. For instance, whilst a large number of samples of crude sewage contained on the average 7,357,692 bacteria per c.cm. the average of the corresponding effluents per c.cm. was 4,966,666 (a reduction of 32 per cent.). The average number of the bacteria of the coli type in the crude sewage (600,000 per c.cm.) was reduced in the effluents to 400,000 per c.cm. The number of spores of Bacillus enteritidis sporogenes, varying from 10 to 1,000 or more per c.cm. in the crude sewage, was found to have undergone very little reduction in the effluents. Both these bacteria are of special interest, being of excremental origin : the Bacillus coli also because of its close association with and resemblance to the Bacillus typhosus ; the Bacillus enteritidis sporogenes because of its virulent character and apparent causal relations to acute diarrhoea. It is argued that if the B. coli passes so readily through the contact beds there is nothing to show thab the B. typhosus will not do the same. Moreover Dr. Houston found that various other species of bacteria, such as the sewage proteus and the B. pyocyaneus, passed freely through the beds. Even streptococci, which are generally known to us as highly virulent M 2 1 64 ENTERIC FEVER but anything but hardy microbes, he constantly found in the effluents. In view of these results, it is difficult to diflfer from Houston's conclusion that " however satisfactory the process may be from the chemical and practical point of view, the effluents from the bacterial beds cannot be reasonably assumed to be more safe in their possible relation to disease than raw sewage slightly diluted, but otherwise unaltered in its bacterial composition." The far-reaching importance of the above discrepancies between the chemistry and bacteriology of so vital a matter need not be insisted upon. Yet, in many instances, public authorities and private individuals are quite satisfied with the ordinary chemical analysis, the biology of the subject being completely neglected. EXCRETA 165 CHAPTEE XVII APPLICATION OF STOOLS TO WELL-TILLED HUMUS— WATEB—DEEP BUBIAL— WELLS In country places I believe that enteric stools may with reasonable safety be applied to the surface of well-tilled soil. They must not be mixed with antiseptics, and they must on no account be buried deeply. They must be placed only a few inches below the surface, and be lightly covered. There is no evidence, so far as I am aware, that fences {enteric or otherwise) treated in this way have ever been productive of harm. The sooner the ground is planted with cabbage plants the better, and it must be borne in mind that, if the soil is to remain sweet, tillage and cropping are a sine qua non, and it is probable that pathogenic microbes succumb in the process. There is no evidence to the contrary. Tillage admits air, and in turning over the ground we have the beneficent effect of sunlight. I have studied somewhat closely for the past eighteen years the result of applying human faeces to a well-tilled humus, and I feel convinced that many who write upon the subject have taken but little pains to inform themselves as to the real facts. The rapidity with which faecal matter disappears in the earth depends upon circumstances, viz. the state of the soil as to tillage, the mass of faeces to be dealt with, and the weather. If the weather be i66 ENTERIC FEVER warm with occasional showers, we find at the end of about three weeks that the whole of the faeces and paper has become humified, and is no longer recognis- able by eye or nose. The smell under all circum- stances seems to disappear in a few hours. If there be drought or frost the humification is delayed, but, strangely enough, the humification is delayed longest if the weather be continuously wet. Under these circum- stances the pores of the soil are closed, and the humus gets sticky and pasty, but the faeces are not and cannot be washed out of the soil. On the top of the soil, water can exert no continuous pressure = What harm are faeces capable of doing when thus applied to the soil ? They are not likely to be eaten or inhaled, they cannot be drunk, and nothing short of absolute proof would make me believe that the bacilli can pass downward to the subsoil water, because, in well-tilled soil, the harder it rains the tighter are the faeces locked up, and with them one must suppose the bacilli, so long as they continue to exist. I have never studied microscopically what one may call the progressive fungology of faeces on their road to humification, but I can say this, that on the surface of the ground in the course of a month or so there appears a green algoid growth, looking somewhat like a covering of moss, and then on digging and taking up a handful of earth one may detect little particles riddled with fungi, often reddish and ultimately black. The end is what the gardener calls ' good rich black mould.' Its fertility is unequalled. I must repeat what I have said, that the place of deposit must be loell- tilled humus. If masses of faeces are dumped down on clay banks sloping to a river they may be washed into the river, and have been washed in many a time. Or they may be driven by torrential rain into deep cracks TILLAGE 167 in the clay, and this has possibly happened in India and perhaps here also. Again I feel tempted to put forward a hypothetical case. It is this : as long as plants are alive their roots absorb moisture from the soil, but when they die the dead root of a tree or strong- rooted plant like the hop may possibly serve as a drain for the direct conduction of moisture to the subsoil. This is purely hypothetical, and I have no knowledge of any such occurrence. In a properly tilled humus there are no cracks or fissures, and any cracks must inevitably be filled up by the crumbly earth. The power of a well-tilled humus to absorb, transform, and humify organic matter is astounding ; and, provided it be tilled and cropped, its power in this way seems steadily to increase, as if * increase of appetite did grow by what it fed on.' In my published works (* Essays on Eural Hygiene * and *The Dwelling-house') will be found details of experiments which show conclusively how great is the purifying power of humus on urine which is slowly filtered through it; and, in short, there is abundant evidence that a well-tilled and well-nourished humus is an absolute protection to our subterranean water- supplies. Further, I believe that, so long as the humus keeps healthy and in a highly productive state, the protection to our water-supplies is proportionate to the thickness and richness of the humus, or, in other words, to the amount of dung applied to it. Further, I believe, and have supported the statement by arguments in the works referred to, that the best return agriculturally is got by the immediate and daily application of faeces to the land, and that while the faecal matter is, in agricultural phrase, * ripening,' one may get a crop of cabbages, and after the cabbages anything 1 68 ENTERIC FEVER and everything. These statements are founded on an experiment now in its eighteenth year, in which the faeces of about one hundred people have been utilised in the manner indicated on an acre and a quarter of land. Now that the garden is in full bearing it returns me over fifty pounds per acre per annum. Is it not time that the people of this country were taught that faeces properly used are a source of health, wealth, and beauty ? This most important matter holds no place in our National Educational System. There are no municipal gardens for showing how faeces may increase the attractiveness and prosperity of a town, and to demonstrate that the man who resolutely applies faecal matter to its proper use gets an immediate and great reward. The people are silently taught that the only * decent ' (!) way of dealing with faeces is to mix them with water. This filthy mixture, by its putrefaction, fills our courts and alleys with sewer gas ; it trickles to our water sources, and the expensive works necessary for attempting to sweeten it and purify it are of such a horrible kind that they are always surrounded by walls which reach higher than the nose and eyes of an or- dinary man. I have always contended that there is too much of Hercules and too little of Minerva in our sanitary arrangements. We see the pipes, the engines, the ventilators, the hospitals, and the smoke of the destructor ; we hear the incessant thud of steam machinery, and feel the rate collector's hand for ever in our pockets ; but we never get a glimpse of the bright side of the matter, the return which Nature inevitably makes to nourish our bodies, gladden our senses, and freshen the air. In the reports of the Local Government Board inspectors we constantly come across allusions to *a TYPHOID BACILLUS 169 polluted soil.' The water-closet has polluted our rivers and the air we breathe ; we now begin to hear of pol- luted soil. The outlook is not pleasant. Sir Eichard Thorne, in a recent most interesting address, alludes to experiments carried out by my friend and colleague, Dr. Sidney Martin, which show that the typhoid bacillus will thrive and multiply in a rich soil previously steril- ised. This is an interesting fact, and I find no difficulty in believing that in the untilled soils, sodden with faecal and other filth, which are found in the close courts of our modern manufacturing towns and in the old quar- ters of towns which in former ages were walled fortresses, the enteric poison may lurk. There is no more diffi- culty in believing that the enteric poison will live in sterilised earth than in believing that it will live in gelatine, which has proved a valuable cultivating ground for so many microbes. Acting upon this know- ledge. Dr. Ballard showed that cold gelatinous food stored in an unwholesome place might become a culti- vating ground for pathogenic organisms, and he pub- lished many facts in support of his contention. But it would be quite as unreasonable to condemn jelly as necessarily a dangerous food as it would be to condemn the soil as the natural lurking-place of enteric because under conditions which cannot exist in Nature the en- teric microbe may exist in it. It is necessary to state this because a careless reader of some of the Local Government Board Eeports might come to the conclusion that the manuring of the land was a serious danger to the public health. A moment's reflection will convince us that the balance of effects resulting from the dunging of land must be in favour of health, and there is no evidence of evil resulting from farming or gardening operations. Agriculturists I70 ENTERIC FEVER of all grades are the healthiest section of our popula- tion. The great cities would be in a most pitiable state if the gardener were not ready to cart away the dung and bring back fresh fruit and vegetables. As the dung of the modern horse bids fair to be cinders, one hopes that a demand will spring up for human faeces, and that the necessary machinery for their decent daily removal will be accomplished. The soils of cities become polluted because there is a deficiency of air and sunlight and an excess of water. The careless inhabitants can get water by turning a tap. They throw it down the middens, they cast it on the ash heaps, they spill it on the surface. The sub- soil is never relieved of water by pumping, and foul liquids are sure to be soaking into it from cracked drain-pipes. Nothing can purify a filth-sodden soil except tillage, and I much doubt whether an imperme- able paving will do any good if there be a chance of drain-pipes leaking beneath it. In some of our filthy industrial styes no sanitary measures short of destruc- tion can possibly do much good, and I fail to see the use of herculean and endless labour in order to secure the survival of the unfittest, unless we give the possibility of wholesome life, which cannot be attained without adequate space. In these places the soil has become polluted because faecal matter has been allowed to escape the action of the humus, and being mixed with water has been de- liberately taken through to the subsoil, out of the reach of natural forces which make for purity, and beyond the possibility of tillage which assists Nature to accomplish her beneficent work in the interest of man. It is only a well -tilled humus that can satisfactorily deal with excreta. If there be an excess of water — i,e. -I- EPIDEMICS 171 if the humus is drowned, as in a sewage farm — then any protective action is very problematical. The following is of interest in this connection : 1894. High Wycombe (Dr. S. W. Wheaton).— Town in a long valley between chalk hills. Eapidly increasing population 15,000 (?). Lies on gravel bed, water mainly from shallow wells, partly from waterworks (private company). Town was sewered in 1882. The sewage runs to a twelve-acre sewage farm about a mile from the town, and * after mixing with a preparation of alumino-ferric oxide ' in a sludge pit, its liquid effluent flows directly on to the land. The water-closets of the town bad, and seldom adequately flushed. Enteric fever had occurred every year since 1886. *^ In one house the admission of a girl with enteric was followed by eight cases, and it was found that {inter alia) the soil-pipe of the closet passed over the well and dripped into it. Again in December, 1894, after a heavy downpour, excreta were washed out of the sewers and into the wells. 1895. Wycombe Marsh (Dr. G. S. Buchanan).— Two miles below High Wycombe, and having the sewage farm of High Wycombe at its upper end. Population 700 in 140 houses. Excreta disposed of partly in privies and pails (the contents beings used for gardens), and partly collected by hopper closets, inadequately flushed and run into soak-away cesspools. In autumn of 1895 twenty-four cases of enteric in nineteen houses situated between two streams — the * Back-water,' 195 feet above Ordnance datum, and the * Wye,' 185 feet above Ordnance datum, running parallel to the Back-water and a quarter of a mile from it. 172 ENTERIC FEVER The direction of the flow of ground water was from the Back-water to the Wye and beneath the majority of the implicated houses. The Back-water runs through the High Wycombe sewage farm of twelve acres and in fact drains it. Owing to the fact that the sewers of High Wycombe are laid in the waterlogged gravel, and that the pipes necessarily leak, an enormous quantity of ' sewage,' estimated at 2,000,000 gallons per diem, is poured on to the farm. The volume of the ' back-water ' is about doubled after passing through the * farm.' In September, 1895, a mill below the village which had been long untenanted was let, and a dam previously partly opened was closed. This stopped the flow in the streams of Wycombe Marsh, with the result that the subsoil water became impregnated with the sewage of High Wycombe, and the wells of the village were more or less affected. Sir K. Thorne Thorne, in commenting upon this case, says that it is interesting, since '* it illustrates a danger which may devolve on one community as the result of works carried out solely in the interests of another community." (See also Beverley, pp. 140 and 185.) The river Wye flows into the Thames at Bourne End. N.B. — Two million gallons of water per diem is the equivalent of seven inches of rain per. diem on twelve acres of land, or 2,555 inches or 212 feet per annum. Again, the deep burial of faeces will preserve them, and not help their destruction, which is what we want. Deep burial in a porous soil may not be without danger. For illustrations of this danger arising from bury- ing infected faeces deeply, I would allude to a valuable MILK EPIDEMIC 173 report made to the Local Government Board in 1877 by Dr. Ballard, on a prolonged outbreak of enteric at Ascot in 1873-4 5-6. The epidemic was a milk epidemic, but the main difficulty was to account for the specific infection of the dairyman's well. Dr. Ballard points out that the water-supply of this district is (or was) from wells sunk into a * running sand ' saturated with water, lying immediately below the denser superficial sand. The excreta of the first case which was imported into the district were buried * in a hole in the sand ' (depth not stated), and further there was a leakage of the water-closet drains into the sand, and Dr. Ballard suggests that the infected material may have reached the dairyman's well by the * running sand.' He puts this view forward as an hypothesis, and not as a proved fact, but the calmly considered notions of so careful and contemplative an observer are not to be neglected. This Ascot outbreak of enteric, affecting sixty-nine persons, mainly of the upper and middle classes, appears to have been started by the importation in 1873 of a case belonging to the well-known Marylebone milk epi- demic of that year. This latter epidemic was due to a case in Buckinghamshire. Thus we see, in these days of rapid transit, how far infections may travel. The Marylebone milk epidemic is a good instance of the wrong disposal of infected faeces, and the danger of mixing them with water. 1873. Marylebone milk epidemic (Mr. N. Eadcliffe). — The cause of this epidemic was traced to a farm in Buckinghamshire. The dairy well had become polluted by long-continued soakage from a piggery, the soakage creeping along the foundations of a wall. Against this wall was the farm * ash heap,' in which the evacuations 174 ENTERIC FEVER of the farmer (who died of enteric) had been buried, and upon which were cast all the chamber slops of the sick man's room. This filthy mixture drained with the soakage from the piggery into the well. It is necessary to repeat that if faeces are placed on to humus no antiseptics must be used. Such addition merely prevents the humus from doing its work. The unpopularity of town refuse with farmers is largely due to the antiseptics which have been mixed with it, and which, to borrow a phrase used by an agriculturist, effectually * Mil the dung.' I believe that a well, by draining the soil, helps to maintain the purity of the soil ; and it is most im- portant to remember that when water for household purposes is pumped from the soil, the slop water re- turned (allowance being made for evaporation) must alwa}/s be less than the water pumped. There is, there- fore, not much danger of getting the soil round the dwelling waterlogged and unwholesome. When, on the other hand, an artificial supply is brought into a low-lying district already sodden with filth, and when we give up pumping and proceed to soak the land with our new supply, the purification of such soil becomes a matter of increasing difficulty. Purification of the soil is attained by tillage, and by allowing the humus to breathe, and not by drown- ing it. At my cottage at Isleworth, where I have a quarter of an acre of land, I have my own well, and I feel certain it is a much safer supply than the public supply of the district. The instances of pollution of private wells by leaking sewers and cesspools are innumerable, but these have been mostly small family epidemics, and there can be SHALLOW WELLS i75 little doubt that on the whole there is safety in private wells — absolute safety if the owner have common sense and will take a little trouble. Private wells in crowded cities must always be dangerous, because of the inevitable leaking sewer. I ventured to express the opinion in 1892 that a shallow well properly made, and in the midst of whole- some surroundings, is a perfectly safe source of water, and it is gratifying to find that this opinion is shared by so eminent an authority as Professor K. Koch. Koch (' Bacteriological Diagnosis of Cholera,' 1894) advocates the raising of water from the subsoil by means of tube wells, which he maintains is a perfectly safe method. He says, " People are now everywhere endeavouring to perfect the supplying of water on a large scale to the highest possible degree, but they should direct their attention to the procuring of water on a small scale also, and seek to limit the spread of cholera to a mini- mum, so far as it depends on water, by improving wells in the manner I have indicated. Just in this respect a great deal still remains to be done." In a report made to the Local Government Board in 1893, by Dr. Bruce Low, will be found a table which shows conclusively how large a measure of protection against enteric fever is afforded by the use of wells for the supply of water, even though those wells may be (as in many instances was the case) badly constructed and negligently kept. In the Gainsborough Kural Sanitary District it was found that in forty-one villages, with a population of 13,063, in which the inhabitants drank well-water, there were in four and a half years twenty- five notifications of enteric ; whereas in ten neighbour- ing villages, with a population of 5,693, the inhabitants of which drank Trent water or canal-water, the number 176 ENTERIC FEVER of cases of enteric was 167. In the first group the incidence of enteric was 1*92 per 1,000 ; in the second group it was 29*3. It will be gathered that my sanitary faith consists in a firm belief (I do not know a single fact to the contrary) in the protection afforded to our water-supplies by a well-tilled humus. I believe that organic filth of all kinds should be kept upon the surface to nourish the humus, and not be placed beneath it to endanger the wells ; and I believe that the great cause of the modern increase of enteric fever has been the water- closet, which has fouled and is still fouling our sources of water. In proportion as we have given up foul water-supplies and have gone further afield the mortality from enteric has lessened ; but the sudden outbursts of late years have shown that we have * scotched the snake, not killed it,' and it is impossible to see any finality or real safety in our sanitary arrange- ments so long as they are dominated by the idea of putting our filth out of sight below the humus instead of on it. OVERCROWDING 177 CHAPTER XVIII ENTEBIC AND OVERCROWDING The late Dr. Murchison was of opinion that over- crowding was not an important factor in the causation of enteric fever, and it is quite true that in comparison with typhus or small-pox, or other mainly air-borne contagion, overcrowding plays an insignificant part among the predisposing causes of the disease we are considering. Nevertheless a reference to the Registrar-General's last Decennial Supplement (supplement to the Fifty-fifth Annual Report, 1895) will show (Table VI., p. 115) that enteric fever was most rife in the more crowded counties. Thus the average death-rate from enteric fever for the whole of England and Wales during the ten years 1881- 90 was -20 per 1,000 persons living. Eleven counties had an enteric death-rate higher than the average, viz. Lancashire, Durham, and Notting- ham, -27 ; North Riding and South Wales, -26 ; East Riding, -24 ; Northumberland, -23 ; West Riding, -22 ; Cheshire, Monmouth, and Hampshire, -21. On the other hand, the thirteen counties having the lowest death-rate from enteric were Hereford, '06 ; Rutland, -08 ; Bedford, -09 ; Wilts and Dorset, -10 ; Somerset, Surrey, and Oxford, -11 ; Suffolk and Berkshire, '12 ; Sussex, Huntingdon, and Cumberland, •13. 178 ENTERIC FEVER Broadly speaking, one may say that the enteric death-rate was highest in the manufacturing counties and lowest in the agricultural counties. Hampshire is the only county which apparently contradicts this statement, so that it may be well to say that the relatively high enteric death-rate in this county is largely due to the big seaport towns, with hospitals (civil, naval, and military) and asylums. The reason for the relative excess of enteric in the more crowded districts is not far to seek. Not only is the pollution of rivers at its maximum in these counties, but the space round the dwellings is often so restricted that it is impossible to prevent the pollution of the air and soil by excremental matter. The rural counties are constantly being threatened with various expensive so-called sanitary works. It is important, therefore, to bear in mind that these counties suffer less from enteric than the wealthy urban dis- tricts. In overcrowded places, where people live night and day in what one may call excremental surroundings, there is no escape from contamination. It must be in air, soil, and water ; in their food ; on their cooking utensils and clothing ; in short, everywhere. The only real remedy for this state of things is space round the dwelling. Great schemes of sewerage and water-supply have hitherto merely increased overcrowding. Our 224 millions of local debt has not abolished enteric, while in some places it appears to have increased tuberculosis and diphtheria. As an instance of enteric in crowded areas, I cull the following from a report by Dr. Bruce Low (1896) on a northern town (Middlesbrough) where enteric is endemic and at times epidemic. MIDDLESBROUGH 179 The population of this town has grown in little more than half a century from 5,000 to over 85,000. It lies on a flat near the sea, and is mainly occupied with the coal and iron trades. The area is (excluding fore- shore and tidal water) some 2,700 acres, and in the most crowded parts 10,000 people are congregated on fifty-five acres of land. Dr. Bruce Low says, '' The older parts of the town are very closely built ; . . . the backs of some of the houses are often shut in by out- buildings, privies, and the like — some [houses] in the old parts of the town are very bad ... in a dilapidated condition. Houses of this class let for as little as one shilling per week, and afford shelter for a very low class of the population. . . . The employment at the works attracts numbers of persons of a shifting class from a distance. Many of these people are improvident, in- temperate, and uncleanly in their habits. . . . " When a high tide coincides with heavy rainfall, the sewers are unable to contain the accumulated sewage and storm-water. As a consequence there is backing- up and ultimate escape of diluted sewage from street and yard gullies, flooding some streets and the basements of houses." The middens are bricked and not cemented, and " the ground below is often saturated with black and filthy fluid. . . . Occasionally a single midden receives the discharge from as many as six privies. These privies are often a short distance from back doors and back windows, and in numerous instances face the pantry window and are within a few feet of it." In one case the people complained that their windows could not be opened ** owing to the abominable odours emitted by the midden. ... In some cases between the backs of dwellings in parallel streets there is a double row of N 2 i8o ENTERIC FEVER midden privies divided by a narrow back passage only four feet wide. . . . The contents of the privy middens are said to be emptied once a fortnight. The wet filth and ashes are mixed and thrown out of the midden into a wheelbarrow, which is emptied out upon the macadamised surface of the front street, and . . . the contents lie in the street for a time while the fluid filth soaks away." Ash closets provided with pans are also in use. They are emptied on an average twice a week, but the system is greatly misused by the householder. We read that the pans are sometimes dusted inside with carbolic powder. " The pan contents . . . are taken to the depot, and after rough articles such as tin cans, matting, and the like have been removed, most of the residue is put into trucks for removal to the rural districts. . . . There is a growing difliculty in getting rid of pan contents. " The dirty habits of the lower classes [in Middles- brough] also increase the dangers above indicated. In- deed, it was found that the largest number of enteric fever cases occurred in those parts of the wards occupied by the roughest class of the population, people who took no care of their houses or their persons, and paid very little attention to the state of their food. Some of these persons sleep in unwholesome * box-bed places,' which resemble cupboards partitioned off from the living-room, and ventilated only by a small aperture, which, when opened, often overlooks the midden a few feet away." Dr. Bruce Low is inclined to think, as well he may, that the fever in this town is " indigenous fever fostered by unwholesome conditions pertaining to the town itself." BICESTER i8i Quite different are the circumstances of the town of Bicester (Dr. Theodore Thomson, 1896), with some 8,000 inhabitants on as many acres of ground, a stragghng and old-fashioned town with a stationary population. Most of the houses have good gardens or yards, and there are vault privies, pan-closets, and a few water-closets. Of the twenty-eight persons first attacked with enteric, twenty- six obtained their water from Crockwell Spring, situated at a point where the town sewer describes a semicircle round it, having the spring in the middle at a distance of some eight feet. This encircling sewer was found to be broken and leaking. I have brought the closely packed manufacturing town into juxtaposition with a country town for the sake of contrast. In a place like Middlesbrough, where people live surrounded by faecal befoulment, there is no possibility of their condition being made better or worse by water-closets. Nothing can remedy such a state of things short of total destruction and recon- struction. Pending that, however, I think the daily removal of excreta should be aimed at, and the local authority should endeavour to acquire a tract of land to give an object lesson in the advantage of a really scientific treatment of excreta. Dr. Murchison was of opinion that the danger of infection from enteric stools was increased by putre- faction. The permitting of faeces to remain about the house for a week or fortnight, just long enough for putrefaction to attain its maximum, must be terribly hazardous. The model by-laws of the Local Govern- ment Board permit privies within six feet of the back- door ! Is no correction for dangerous sanitary negligence i82 ENTERIC FEVER ever to be tried with the individual ? A gentleman is placed in the dock for not having his bicycle lamp lighted; is nothing to be done to the man who endangers his neighbour's health by swinish apathy? Many towns correct filthy language by fine ; can nothing be tried against filthy acts, which are infinitely more dangerous ? In a small town like Bicester, or in a village, the problem is very different. If the inhabitants would abolish their water-closets, and with them all under- ground sewers and cesspools, and allow their slop-water and storm-water to run in open channels or filtration gutters, all risk of epidemics of enteric would end. In such a place the great need is properly organised and daily scavenging. Every receptacle for filth — dry closet, ash-bin, slop-gutters — all should be cleaned and swept out ex}ery day^ and the stuff put to its proper use on a spot of public ground where the people may receive an object lesson which should show how much it is to their own interest to be cleanly. I have been at some pains to lay down what I consider to be the true lines for disposing of enteric excreta, and incidentally for disposing of putrescible filth generally. I am well aware that in big cities, where houses have no curtilage, the convenience of the water-closet will certainly override all other con- siderations. If any improvement is to take place on the lines I have indicated, such improvement must begin at the outskirts of towns and not in the centre. But the water-closet is practically established by law, and no encouragement is given, even in country places, to the householder who may think as I do, and who may wish, for his own health and profit, to work out his sanitary salvation on his own premises, and RESPONSIBILITY 183 independently of the sanitary authority. No man, of course, must be allowed to endanger the health of his fellow-man; but we all do this when we poke excrement into a sewer without any certain knowledge that it will not leak to our neighbour's water. Indi- vidual responsibility in sanitation no longer exists, and it is impossible to fix any responsibility on public bodies. The long list of epidemics caused by public works must make us think that this system is not working quite satisfactorily. In my published writings I deal with these questions at some length, and I also try to work out some of the details for the attainment of a profit- able and safe sanitary independence. Great ' sewage- schemes,' involving large expenditure, are always supported (naturally enough) by the small shopkeepers and the wage-earning classes, who generally control our municipal government. APPENDIX OF EPIDEMICS 1867. Guildford (Dr. George Buchanan). — 250 cases due to pollution of a new chalk well supplying part of the town, by quantities of sewage leaking from an old ill- constructed sewer. Dr. Buchanan alludes to the fact that the conversion of privies into water-closets was a danger, especially in the chalky soil of Guildford. Sir J. Simon, commenting on the case, says, ' The new well, no one could doubt, was most dangerously situated ; in the porous and fissured chalk stratum it was within ten feet of various sewers, one of which indeed was traversed by the iron delivery pipe of the high service,' &c. 1870. Warwick (Dr. Buchanan). — ' The public water-supply of the town scandalously filthy.' 1873. Sherhorne (see p. 147). i84 ENTERIC FEVER 1870-73.— Mr. Simon gives a list of 147 places infected in these years. In almost all of these reports the words ' polluted water' or their equivalents appear, but the details are seldom given, and no further analysis would prove profitable. 1874. Lewes (Dr. Thome Thorne). — 450 cases, due to pollution in the course of and at the periphery of water service caused by intermissions in the supply. The water main at one spot passed through the centre of one of the public sewers. ' This sewer was in consequence opened up, and when the arch of the culvert was removed at the point where the water main passed through it, a jet of water suddenly shot up into the air. There was a hole in that portion of the water main which was inside the sewer.' 1876. Tideswell, Derbyshire (Dr. Thorne). — Outbreak of enteric. ' Spread of disease favoured by conditions in an intermitting water service allowing of suction of foul air into water-pipes.' 1878. Dewshury District (Dr. Thome).— Population 124,286. Excessive mortality, especially enteric. ' Water-supply for some districts liable to pollution at its sources, and periodically fouled in the delivery mains during intermissions in the service.' 1879. OJcehampton (Dr. Blaxall). — ' Water-supply exposed to pollution by direct communication between water mains and closets.' 1879. Bedhill and Caterham (see p. 139). 1880. Enfield (Dr. Parsons). — Occasional occurrence of enteric. Causes multiple. ' Probable local contamination of intermittent water service by reflux of foul matters from water-closet.' 1880. Haverfordwest (Dr. Parsons). — Epidemic of enteric. ' Public water-supply insufficient and liable to contamination both at reservoirs and in course of delivery, by sewer air sucked in during intermissions through leaky flush-valves.' 1880. West Cowes (Dr. Ballard). — Enteric fever prevalent. ' Intermittent water-supply liable to pollution in the mains.' 1880. Sandown (Dr. Ballard). — * Water-supply from water- works taken from a stream much polluted in its course by sewage and excrement.' 1880. Ventnor (Dr. Ballard). — ' Water-supply from waterworks intermittent, and polluted dangerously by free admission of sewer air into reservoir by means of overflow pipe.' 1880. Llanelly (Dr. Parsons). — ' Water-supply constant and APPENDIX OF EPIDEMICS 185 plentiful, but liable to contamination by filth of population living above intake.' 1880. Newlyn East, Cornwall (Dr. Ballard). — 'Very scanty supply of water, and mainly from a well with which the village drain freely communicated near its outlet.' 1880. Totnes (Dr. Parsons). — 'Outbreak apparently due to failure of town water-supply in the exceptionally dry summer, and consequent want of flushing of sewers, drains, and w.c.'s.' 1881. BlacJchum (Dr. Airy). — 238 cases due to fouling of a culvert belonging to the water company by soakage from privies and surface drainage of adjacent cottages at the village of Guide, in which there had been cases of enteric fever. 1881. Bodmin (Dr. Parsons).— Severe epidemic. Cause? Water-supply liable to contamination. 'Possibility of reflux of foul matters into public water-supply from closets flushed direct from an intermittent service.' 1882. Bojigor (Dr. Barry). — 548 cases caused by the filter beds being flooded with raw river-water containing excremental matter. 1884. Sheemess (Mr. John Spear). — ' Water service inter- mittent, water mains often laid in same trench with tributary sewers, and interchange of contents between house drains and house service-pipes several times discovered.' 1885. Kidderminster (Dr. Parsons). — 1,200 cases at least. Probably due to in-suctions of impurity during intermissions. The fouling of a deep well by percolation of subsoil water and sewage during a drought also not by any means excluded. 1883. Hitchin (Mr. W. H. Power).— ' Outbreak of enteric associated with defects of the public waterworks, permitting occasional back-flow of sewage-polluted river-water into the pmnping-well.' 1884. Beverley (Dr. David Page). — 231 cases due to con- taminated supply of Beverley Waterworks Company, derived firom deep chalk wells (333 feet in all). Company's well and reservoir close to sewage-irrigated field belonging to East Kiding County Lunatic Asylum. Sewage firom asylum is supposed to have trickled alongside the well shaft. 1885. Faldingworth (Dr. Gress well).— Small outbreak trace- able to pump-water polluted by washings from a fever case imported fi:om Newark. 1887. Margate (Dr. Page). — Increase of mortaHty from enteric. i86 ENTERIC FEVER ' Water-supply pumped from a well in the chalk, on the outskirts of the borough beside a populous and growing neighbourhood. Water of bad quality and exposed to contamination by soakage of sea-water and from cesspools.' 1888. Mountain Ash (see p. 145). 1888. BucJcingham (Dr. Parsons). — Sudden outbreak of enteric, confined at first to a poor suburb of the town, and specially affecting persons drinking water from a particular ' spout.' The water conduit to this spout exposed to pollution from a leaky drain which had received specifically infected excreta from a previous case of enteric fever. 1889. Longton, Staffordshire (Mr. Spear). — 155 cases. * Special incidences of primary invasion in part of the town getting a supply from a particular section of the public water service.' 1889. Bochester (Mr. Spear). — Public water-supply from wells in the chalk. ' In very many cases at Strood, and in a few in Eochester, I found water-closets supplied direct from the mains, i.e. without the intervention of any cistern or tank. The danger of in-suction of air, and even of solid matter, into the water-pipes from closet-pans, during temporary discontinuance of water- pressure, is well known to attend this objectionable arrange- ment.' 1889. Houghton-le- Spring (see p. 141). 1890-91. Tees Valley (Dv. Barry).— 1,463 cases due to public water-supplies taken from the Tees, which was more than ordi- narily polluted after a flood. The water-supplies were owned by the Darlington Corporation and the Middlesbrough Water Board. ' The river is found to be at all times subject to conditions of the gravest fouling, by reason of the fact that human excreta and other filth are knowingly and deliberately conveyed to it.' 1891. Rotherham, Bawmarsh, and Masborough (Dr. Theodore Thomson). — 211 cases. Caused by the pollution of the High Level Water- Supply of the Eotherham Corporation. Pollution caused by the washings of manure inclusive of human excrement into the streams contributing to the public supply. 1891-2. King's Lynn (Dr. Bruce Low). — 226 cases, mainly in February and March 1892, due to fouling of public water-supply by the direct inflow of manurial filth, inclusive of human excreta and typhoid excreta after a sudden thaw and flood. 1890-93. Newark (Dr. Bruce Low).—' Out of a total of 297 APPENDIX OF EPIDEMICS 187 cases of enteric fever, 78-5 per cent, occurred among that half of the population which habitually consumed water from the public service.' This water consisted in part of raw unfiltered water from the Trent. 1892-93. Chester -le- Street (Dr. Maclean Wilson).— 58 cases, mainly occurring in the area of the Consett Water Company, which obtained its water from the Stanley Burn. The burn was more or less fouled with excrement, but three miles above intake was a cottage, draining into the burn, which, in October 1892, contained four cases of enteric. The Consett water, before distribution, was subjected to sand filtration, but it is pointed out that the sand was obtained from the banks of the polluted Eiver Wear. 1893. Atherstone WarwicTc (Dr. Wheaton). — Outbreak of enteric due to the introduction into the town water mains of polluted water (particulars not given). 1893. Worthing (Dr. Theodore Thomson). — 1,411 cases in Worthing, West Worthing, and West Tarring. The epidemic in Worthing caused by leakage of a sewer into a heading run from the bottom of a deep chalk well. The epidemic in West Tarring and West Worthing presumably due to infection of the water mains by the entrance of filth firom the surface through ball hydrants. Speaking of the Worthing epidemic. Sir E. Thome Thome says, ' Chemistry had all along failed to detect in the water any definite impurity, and it was only in the later stages of the epidemic that the results of bacterioscopic examinations went to finrnish conclusive evidence, not only of its being fouled by faecal matter, but of its contamination by the specific material of enteric fever.' Both waterworks and sewers the property of the Worthing Corporation. 1880. Newport, Isle of Wight (Dr. Ballard).— 'Water-supply from water- works good and abundant ' {vide 1894). 1894. Newport, Isle of Wight, with ParWiurst Barracks Prison (Dr. Theodore Thomson). — 516 cases (population over 10,000). 4*2 per cent, of those drinking ' Newport water ' were attacked ; 1*7 per cent, of those di'inking from private wells. The water was from chalk wells imperfectly lined, polluted by an adjacent pond, and probably by more distant leaking cesspools. i88 ENTERIC FEVER of which there were many. Water found to contain Bacillus coli. 1895. Baunds, NortJiants (Dr. Bruce Low). — 129 cases, mainly traceable to two public wells which had been distinctly infected by the rinsings and washings of utensils and linen and stools of enteric patients. SANITATION OF CAMPS 189 CHAPTER XIX TRE SANITATION OF CAMPS^FLIES AND THE SCIENCE OF SCAVENGING' In the recent debate ^ at the Clinical Society of London on Dr. H. H. Tooth's paper ^ on enteric fever in South Africa it was established : (1) that the number of flies in our camps was prodigious ; and (2) that these flies were largely a result of the military occupation. There seems also to have been a very general consensus of opinion (3) that flies may convey infection. It becomes therefore of great importance to consider the genesis of flies ; and I trust that one who has no claims to be considered a dipterologist may be pardoned for recalling a few common facts. Flies multiply at a prodigious rate. Given a tempe- rature sufficiently high to hatch the eggs, their numbers are only limited by the amount of food available for them. Linnaeus is credited with the saying that three meat-flies, by reason of their rapid multiplication, would consume a dead horse quicker than would a lion, and the fact that certain diptera having some outward re- semblance to the honey-bee lay their eggs in the dead carcasses of animals probably led Samson and Virgil to ' Eeprinted from the Lancet, May 18, 1901. 2 Ibid. March 16, p. 786, and 30, 1901, p. 932. 3 Ibid. March 16, 1901, p. 769. I90 SANITATION OF CAMPS make erroneous statements with regard to the genesis of honey and the manufacture of bees. The breeding of ' gentles ' for ground-bait is an industry the practisers of which could probably give much information as to the nicety of choice exercised by flies in selecting material for feeding and egg-laying. According to Packard the house-fly makes selection of horse-dung by preference for ovipositing, and as each female lays about 120 eggs and the cycle of changes from egg to fly is completed in less than three weeks it seems probable that a female fly might have some 25,000,000 descendants in the course of a hot summer. Other varieties of flies multiply, I believe, still more rapidly. As flies multiply upon, and in, organic refuse of every kind it is obvious that the sooner such refuse is placed where it cannot serve for the feeding and hatch- ing of flies the more likely is the plague of flies to be lessened. The most commonly available method for the bestowal of organic refuse is burial. The egg-laying of flies in dead carcasses commences at the very instant of death, or even before death in the case of enfeebled animals. This fact has been insisted upon by Megnin in * La Faune des Cadavres,' and appears to be true of human beings dying from fever. It is obvious, there- fore, that there must be no delay in the burial of organic refuse, and that the burial of animals and excreta is quite as important as the burial of human beings. After a great battle it may not be possible to follow this advice, but nevertheless there can be no harm in insisting that the instant burial of all organic refuse must be the aim of those who are called upon to guard the public health, whether military or civil. It is impossible to lay down any line of action which shall be the best under all circumstances, and those SALISBURY PLAIN 191 who, like myself, have not been through the South African campaign are incompetent to deal with the special circumstances of that campaign. Nevertheless, I am of opinion that much that I have witnessed on Salisbury Plain in connection with camp-scavenging is bad and is not calculated to teach the soldier the right principles of dealing with organic refuse, which is always his most dangerous enemy. The science of scavenging requires to be taught. If the duty of sca- venging be left to the ignorant and be controlled by persons who think that necessary details are beneath their notice, then annoyance and disease are the only results possible. If the scavengings of a camp are to be satisfactorily dealt with the question of their ultimate disposal must be ever present in the mind of the scavenger. The materials collected have to be burnt, to be buried, or to be otherwise dealt with. The mere dumping of refuse in mixed heaps ought certainly to be abandoned, and the contents of the latrines ought to undergo immediate superj&cial burial at the nearest available spot in order to avoid cartage and spilling. In many cases it should be possible to bury the excreta in the immediate vicinity of the spot where they are dropped. We hear of excreta being buried in trenches ten feet deep, but such a course must mean that they are left exposed to give off odours and to breed flies for many hours before they are under ground and covered up. I have consulted a gravedigger on this question and asked him, * If you were ordered to dig a grave ten feet deep what breadth and length would be necessary, and what time would you require ? ' His reply was that (in chalk) the grave would have to be six and a half feet long and three and a half feet wide, and that he would rgquire a day and a half to 192 SANITATION OF CAMPS complete the work. It is certain that thirty-six or forty- eight hours' delay in the disposal of faeces is most undesirable. I have always advocated the burial of faeces in shallow furrows rather than in deep trenches, and, in this country at least, where alone I have had experience, I am convinced that this is the only reason- able course to pursue. If properly done all o£fence to eyes or nose is thus ended and the faeces cease to attract either flies or rats. The faeces can be covered continuously as soon as they are dropped, and there is no need of having malodorous open trenches partially filled which are waiting to be completely filled before being covered up. This burial of faeces must be done methodically and carefully and with every attention to detail. The pro- ceedings must be precisely those of a gardener who is intent upon raising crops. The fact that in war the crops may never be harvested is quite beside the mark and affords no excuse for slovenly procedures which are a danger to health. Nitrification in the soil is the aim equally of the sanitarian and the agriculturist. If a plot of ground fifty yards long and fifty yards wide — slightly more than half an acre — be allotted for the disposal of faeces this should be marked off into, say, sixteen strips, each about eight feet wide and fifty yards long, with a narrow path of about eighteen inches between each strip to allow for watering and cultiva- tion. The line of the furrows must be accurately marked by a cord and reel in the ordinary way, and the digger must move continuously backwards in order to avoid trampling on the freshly dug ground. The making of the furrows should commence at the point furthest from the latrines and it should gradually come nearer to them. The earth removed from the first furrow TRENCHES 193 should be wheeled down near the latrines, where it will be ultimately wanted to cover the last furrow which is dug. The capacity of the furrow or little trench will depend upon the size of the spade. I find that, working in ordinary garden soil with a spade having a blade nine inches long and seven inches wide (the furrow being consequently nine inches deep and seven inches wide), eight stable-bucketfuls of soil each holding two and a half gallons, or about twenty-two pounds weight of earth, were removed. This amounts to two and a half bushels of soil, weighing 176 pounds, as the measure of the capacity of a trenchlet eight feet long. This trench must be filled with excreta, and great care must be taken that nothing except faeces and paper and the accompanying urine is placed in it. If broken crockery or old tins are accidentally mixed with the excreta they must be removed. The trench being filled with faeces, mark out a digging line at a distance equal to the width of the spade (seven inches) behind the edge of the first trench and then cover the faeces in the first trench by the earth removed in making the second. Owing to the draining away of urine and moisture and their great compressibility it will be found that the excreta undergo a considerable diminution of bulk when tipped into the trench. When the earth of the second trench has been removed and shovelled on to the top of the first trench it will be found that there is a raising of the general level of the ground, and the second trench will be found to have a cross section which is rather triangular than rectangular, owing to the oblique direc- tion of its front wall, which is composed of a sloping bank of friable earth. The surface of the ground must be left crumbly, smooth, and perfectly neat, like a well- prepared garden bed. No particle of faeces or paper o 194 SANITATION OF CAMPS must be left uncovered. There will be no offence to eye or nose, no putrefaction is possible, and the faeces are beyond the reach of dipterous insects, and if there has been no delay in the collection and burial of the faeces they cannot have been used for oviposition to any great extent, so that the soil will not become infested with * grubs.' How many men will provide the quantity of faeces which can be placed in a trench eight feet long from which 176 pounds weight of earth have been removed ? The answer to this question is governed by bulk rather than by weight. If faeces and earth were equal in bulk for equal weights and if we allow a quarter of a pound of fasces for each man — for the urine soaks away and qua bulk may be neglected — then the answer would be 176 X 4 = 704. If the faeces are weight for weight four times as bulky as the earth, the answer is 176. In any case it seems safe to say that a trench eight feet long, nine inches deep, and seven inches wide will suffice to take the faeces of 100 men. This estimate entirely accords with my experience gained in my garden at Andover, where the faecal accumulations of twenty cottages have been disposed of daily in the manner indicated for eighteen years, and where it takes at least five years to cover an acre of ground in this way. Those who have not had experience of this method of dealing with faeces are apt to have exaggerated views as to the amount of land required. If a trench eight feet long and seven inches wide is sufficient for the disposal of the daily quota of excreta from 100 men, then ten such trenches occupying an area of eight feet by seventy inches — say six feet— is enough for 1,000 men, and one strip of ground fifty yards long and eight feet wide would serve for a regiment of 1,000 men for twenty-five VEGETATION 195 days, and the sixteen strips would serve for 400 days — let us say half an acre per annum per 1,000 men. The actual area necessary will depend to some extent upon the nature of the soil and the care and skill of the scavenger, but in no case can the area required be regarded as a bar to the process— certainly not on the veldt or on Salisbury Plain. It need not be insisted on that a scavenger must be incessantly at work. The excreta should be taken up as soon as dropped and be placed in a covered pail, and the pail when full should be emptied into the furrow and covered up. In this way effluvia are stopped and ovipositing by diptera is rendered impossible. Further, this method of disposing of faeces necessitates no increase of the impedimenta of an army ; no lime or chemicals are needed, and no apparatus beyond a spade and a set of garden tools. The ground beneath which the faeces are deposited should when the work is done have the appearance of a well-prepared garden bed and it will need little atten- tion until it is covered with herbage of some kind. The only question remaining to be decided is as to what that herbage should be. There can be no camp without water-supply, and in every camp one of the sanitary problems is the disposal of waste water. Some of this waste water should be used in time of drought for laying dust and encouraging fertility in that small area of ground beneath the well- tilled surface of which the faeces are safely bestowed. Then, the higher the temperature the quicker will the ground bring forth green leaves to freshen the air. Whether the crop be grass, cabbage, cereals, onions, mustard and cress, lettuces, spinach, or what not must depend upon cir- cumstances. I think the seeds sown in such ground should always be those of culinary vegetables, which o 2 196 SANITATION OF CAMPS may prove a real blessing if the camp be long occupied. With a little care in a hot climate one may have a green covering of grass or mustard and cress in a week, which at least will give off oxygen to the air even if it do not serve as an antiscorbutic diet for man and beast — a diet which may just supply that something which is lacking in tinned and salted pro- visions. In a temporary camp these methods of excrement disposal are the best on the grounds of immediate hygiene. In places like Salisbury Plain, which are to be used as camping-grounds year after year, latrine gardens are essential, and, if properly managed, should furnish a good many acceptable extras for the canteens. Last year (1900) at Perham, on Salisbury Plain, there was a field of many acres occupied by the scavenging contractor and placed a few hundred yards from the camping-ground. On this were piled heaps of camp refuse, old tins, meat bones, broken victuals, packing materials, and faeces which had been * dumped ' with a view to burning when dry enough. In their recent state these heaps (in which flies were swarming) could be smelt for a quarter of a mile down wind, and when they began to burn the offensive smoke drifted still further and not seldom over the camps themselves. This haphazard method of * dumping ' refuse in pesti- ferous heaps is not economical, not even from the point of view of the area of ground required, and would be rendered unnecessary by a little care in collection and the judicious use of the spade by men who knew how to turn these despised materials to profitable account. Horsedung in the same way should be neatly stacked in heaps like hotbeds, protected at the sides and covered with earth. In this way the flies would be prevented KITCHEN REFUSE 197 from feeding and egg-laying on the dung, large quanti- ties of saladings might be produced, and when the camp was moved this well-rotted material should be applied to the camping-ground with a view to the renovation of the turf. On Salisbury Plain the growth of summer is trodden under foot and there is no systematic reno- vation in the winter. On turf downs the actual camp- ing-ground should be changed every year and the ground * top dressed ' as soon as the camp breaks up in the autumn. Without careful management and good husbandry these downs will soon be trampled and scuffled into a dusty wilderness. In the same way all the kitchen refuse should (after utilisation to a maxi- mum extent in the stock-pot, &c.) be neatly stacked, protected at the sides, and covered with earth. All organic refuse should be completely protected by soil from the attacks of diptera, and its fertilising properties should be utilised forthwith. It is sometimes said that we ought to be ready to forgive the house-flies for the annoyance which they cause to us because of their great services as sca- vengers ; but I am rather inclined to take the view that the presence of flies is a reproach to us for not putting organic refuse to its proper use, and that the fly is a robber which has been bred in material which we have deliberately allowed to lie above ground instead of covering it with soil. The scrupulous sweeping up of crumbs and food particles immediately after meals and the instant removal of the remains of food to fly- proof larders need not be insisted upon. I believe that a great advance in domestic hygiene will have been made when the custom is more general of removing dung every day from our stables, piggeries, cattle-sheds, and poultry-runs, and stacking it carefully so as to 198 SANITATION OF CAMPS prevent the access of diptera, or burying it immediately beneath the surface of well-tilled soil with a view to the production of crops. We pity the horse * turned out ' in a paddock when we see it tormented with * flies.' Few of us pause to think that if the horsedung had been collected daily and put to more profitable use instead of being allowed to lie about and generate a plague of flies the animal might have been happier and the dung might have been more valuable for fer- tilising purposes. When flies breed in dung-heaps the larvae eat the dung and leave the straw. If each fly needs one grain only of sustenance then the 25,000,000 which I have stated as the possible season's progeny of a female house-fly will be capable of robbing a farmer of 25,000,000 grains of fertilising material, which at 7,000 grains to the pound works out at 3,571 pounds, or considerably more than one and a half tons. It is bad economy to have your scavenging done by flies and sad to see your potential wealth make to itself wings and fly away. In my garden at Andover where human excreta have undergone daily superficial burial for about eighteen years there is no excess of flies, and I have come to the conclusion that an essential part of garden management is the daily collection of all garden offal, such as dead leaves, fallen and rotten fruit, &c., and either superficially burying or stacking it so that it shall not serve as a breeding-ground for insects which often prey upon the plums and peaches in the autumn. In the management of refuse I am no advocate for the use of chemical disinfectants. These are expensive, generally evil- smelling, often poisonous, and lead to an increase of material to be transported. The soil is quite capable, with proper management, of turning all organic refuse into * soil ' — a fact which the experiments of Sir NEATNESS 199 Seymour Haden and myself have abundantly proved. Our experiments have also shown that from the point of view of the innocuous transformation of organic refuse into * soil ' deep burial is a mistake. This is true alike of dead animals and of excreta. We are happily hearing less of the pollution of the earth and of the growth of microbes and toxins in the soil, and even from the laboratories of bacteriologists we are learning that the soil is our best friend. The use of quicklime in the treatment of excreta is, I believe, quite unnecessary. My experiments in burying small animals tend to show that the quicklime preserves the body and mischievously prevents the beneficent action of the soil. In the manage- ment of refuse, there must be no slovenly * dumping.' What is wanted is proper sorting at the time of collec- tion, great attention to detail, absolute neatness, and an appreciation of the ends to be attained. In recommending the immediate collection of all organic refuse and its instant covering with earth, I am making no new recommendation. Moses had had experience of a * plague of flies ' in Africa and was no novice in the matter of camp-management. He found it necessary to be most explicit in his directions for the treatment of excreta. These directions are given in Deuteronomy xxiii. 12-14, and I find that in the Eevised Version of the English Bible there is an interesting change in the passage. The old version runs thus : * Thou shalt have a place also without the camp, whither thou shalt go forth abroad : ' And thou shalt have a paddle upon thy weapon ; and it shall be, when thou wilt ease thyself [sittest down] abroad, thou shalt dig therewith, and shalt turn back and cover that which cometh from thee : * For the Lord thy God walketh in the midst of thy 200 SANITATION OF CAMPS camp, to deliver thee, and to give up thine enemies before thee ; therefore shall thy camp be holy : that he see no unclean thing in thee [nakedness of anything], and turn away from thee.' The new version says (verse 13) : * Thou shalt have a paddle among thy weapons,' and as a variant for paddle gives * shovel ' in the margin. The passage, therefore, means that a shovel for burying excreta immediately is a necessary implement in every camp. AN EXPERIMENT IN SANITATION 201 CHAPTEK XX AB EXPERIMENT IN SANITATION— COLLECTION OF BAIN-WATEB— DISPOSAL OF SLOP-WATEB' This cottage is represented {see fig. 6) not because of any architectural beauty, but because it presents points of interest. It forms the lodge of Gallagher's Copse, which is a mile from Andover Junction, just outside the borough boundary. The borough having recently adopted the Model By-laws of the Local Government Board, it became necessary to trek over the border in order to escape from possible hindrances and prohibitions — an important matter, because the owner is, in the matter of house-building, an experimentalist. The soil is chalk. The foundations were laid out by the aid of a compass, in order to ensure that one angle of the cottage should point due north. This arrangement ensures that there is a possibility of some sunshine upon every wall of the house at every season of the year. The accommodation consists (see fig. 7) of a living-room (l), three bed- rooms (b, b, b), scullery and wash-house (s), glazed verandah (v, v), earth closet (c), wood-house (w), and rain-water tank (t). * In the house it will be noticed that there is a door front and back, so that the passage can be swept by a thorough draught ; that no room communicates directly > Eeprinted from Country Life of July 6, 1901. 202 AN EXPERIMENT IN SANITATION with any other room ; and that every room has a fire- place, which, from the point of view of ventilation, is most important. No fireplace is placed against an out- side wall. The chimneys do not get chilled, and * draw ' admirably. This cottage contains what ought to be the minimum accommodation, viz. a living-room, and a bedroom each for parents, boys, and girls. The scullery and wash- house is so placed that, although it can be reached under cover, the smell of cooking and the steam of washing need not invade the dwelling-house. The earth closet is well removed from the rooms, but, nevertheless, can be reached under cover, via verandah and wash-house. The walls are built of * mud,' with rough-cast on the outside. Mud {i.e. chalk puddled up with a certain proportion of straw), flints, and timber are the only building materials found in the district. Most of the clay-pits in the immediate vicinity have been long worked out, and there is no stone. Mud is a non-conductor of heat, and is consequently a very warm material. It is said in the district that frozen water-pipes are very uncommon in mud houses. It is very lasting, provided it be kept dry. Mud walling should be begun in March, and should not be carried on after the beginning of September. It is not advisable to hurry your operations. Foundations are necessary for mud walls, and these should be of flint, concrete, brick, or stone. The mud is 15 inches thick, and with rough-cast on the outside and a lining of match-boarding the thickness of the walls is about 17 inches, and the fireplaces being all in the centre and every side exposed to the sun, it is needless to say that the cottage has proved a very snug winter residence. The floors are of concrete, finished in granite cement, and the skirtings are of the same material. PLAN OF COTTAGE 203 1 J 1 ^ , I °1 pq PR a^ S3 R J \ 204 AN EXPERIMENT IN SANITATION Mud walls are inexpensive. The price paid for the walls of the above cottage was 5s. per perch, i,e, a piece of wall 1 foot high, 15 inches thick, and 16^ feet long. The Model By-laws of the Local Government Board say that the walls of a dwelling-house must be of hard and incombustible material bonded together by good mortar or cement. Now as mud is not hard, contains straw, and is not bonded with anything, it is doubtfully by-legal in districts which have adopted these Model By-laws. In the late fire at Andover it was found that while the thatched roofs blazed, the old mud walls of the cottages withstood the fury of the flames. When the tendency of by-laws is to boycott a local building material and to extinguish a local industry, the 'pros and cons ought to be very carefully considered. An interesting feature of this cottage is the rain- water tank. Although I have a deep well close at hand which supplies an abundance of pure water, I was anxious to ascertain how far rain-water falling on the roof was capable of being utilised for household purposes, notwithstanding that in some districts of England cottages which are dependent upon rain-water only are not permitted. With this end in view, I was careful to provide a very plain, simple roof, without recesses for the lodgment of dirt or nests, and it was this which led me to use slates as a roofing material in preference to the more picturesque tiles which grow moss. My rain- water tank is constructed on the principle of the Venetian cistern. In a city which reached the highest pinnacles of commercial and artistic supremacy on ' rain-water,' one is tolerably sure to get valuable ideas for the collec- tion and storage of that commodity. The Venetian cistern is of large capacity, and is so arranged that all water drawn from the central well has previously passed RAIN-WATER TANK 205 through a sand j<er. The tank is circular in form, having an internal diameter of 7 feet and a depth of 10 feet. It is divided down the centre by a diaphragm, which is perforated at the bottom by three agricultural drain pipes. Each half of the tank contains 3 feet of filtering material consisting of (from above, down) 1 foot of coarse gravel, 1 foot of fine gravel, and 1 foot of sand. The rain-water which falls from the roof passes through two strainers contained in an ornamental vase, and then, before being pumped, passes down through 1 foot of coarse gravel, 1 foot of fine gravel, and 1 foot of sand, and up through a similar filter, before it can be drawn from the pump. The tank is constructed entirely of cement concrete, and the pump has a copper suction pipe. It was important to avoid the use of lead, iron, or galvanised iron for the storage of rain-water intended for dietetic purposes. It will be noticed that all the water has to be raised by a pump, so that none of it can accidentally run to waste. The drips from the pump are conducted back into the unfiltered half, and should a boy play with the pump, he will merely ensure a double filtration for the water, and will not be able to waste any of it. I believe that half the water which we are supposed to * use ' is merely wasted by carelessness and bad taps. It will be noted that the water tank has been brought to the front of the house, and that an ornamental vase has been used for conducting the water from the roof. Anything amiss with the water tank will be noticed at once. This seems better than a dirty water-butt in an obscure corner. Those who have more money and taste will, I hope, soon outdo me in this direction. I commend the rain-water tank to the attention of architects. It may be well to dwell for a moment on the powers of this roof as a rain collector. The area of the roof is 2o6 AN EXPERIMENT IN SANITATION (approximately) 1,100 square feet, and if the annual rainfall fluctuate between 24 inches and 30 inches, then the amount of rain falling upon the roof will vary from 2,200 cubic feet to 2,750 cubic feet. If we take a cubic foot as the equivalent of 6| gallons, then we may say that the amount of rain annually falling on the roof will fluctuate between 13,750 gallons and 17,187 gallons. If we put the average water-supply of the roof at 15,000 gallons a year, or rather more than forty gallons a day, we shall not be far wrong. Water experts say that in towns we want a supply of forty gallons per head per diem. The dweller in the clean country is content with much less than this, and I feel convinced that ten gallons a day is an extravagant estimate for the daily supply of a perfectly clean peasant who does clothes-washing at home, but has not the power of wasting water. The storage capacity of the tank is about 1,600 gallons, or forty gallons a day for a drought of six weeks. The water is excellent, odourless and colourless, and altogether very unlike ordinary rain-water. The water of this cistern was analysed both chemi- cally and bacterioscopically for the Eoyal Commission on Sewage Disposal on November 14, 1901, and with the following results : Parts per 100,000 by weight. Ammoniacal nitrogen 0*064 Albuminoid „ 0-020 Nitrite 0-033 Nitrate 0-086 Oxygen absorbed from permanganate r at once . 0-23 at 80° F. 1 after 4 hours 0-48 After incubation at 80° F. for 6 days { ^l^^f^ * ^'^f L after 4 hours 0-79 Combined chlorine 0-16 Dissolved oxygen (parts per 1,000 by volume) . 2-8 WATER ANALYSIS 207 * Sample clear but yellow, no sediment, peculiar faint smell rather like soot.' The above is a typical analysis of rain-water. To the eye and palate it is the best sample of rain-water I have ever seen, and it has been used for all domestic purposes. It should be said that the yellow colour is very slight. Personally I cannot detect any smell, but there is a faint taste of terra-cotta. Dr. Houston found 25 bacteria per c.c. on gelatine at 20° C, and 7 per c.c. on agar at 37° C. The tests for Bacillus coli and Bacillus enteritidis sporogenes gave negative results. These analyses, and those given on pp. 129-130 in connection with my shallow garden well, are full of in- struction and show how chemistry and bacteriology are needed to check each other, and how both need to be checked by a knowledge of source and circumstances. The disposal of slop-water is always an important consideration in cottage management. Usually this means slop-water plus roof-water, but in this cottage the roof water has been provided for. The amount of slops, allowance being made for evaporation in cooking, and washing and drinking, must always be considerably less than the water consumed. Economy in the use of water lessens the slop difficulty. In this instance the slops are strained and filtered, and allowed to flow away in a * filtration gutter,' to be presently described. The arrangements are on the south side of the. cottage, well exposed to the sun, so as to favour evaporation. The sink is just beneath the window of the scullery, and the waste-pipe, without trap of any kind, passes through the wall, and terminates in a free end about 18 inches from the wall and 2 feet 6 inches above the 2o8 AN EXPERIMENT IN SANITATION level of the ground. The waste-pipe empties itself into a strainer and filter, which are placed about 15 inches from the cottage wall, so as to avoid the risk of splash or back soakings or accumulations of * dirt ' and insects between the wall and the filter. The strainer is placed on the top of the filter, and the filter discharges its water on to a filtration gutter. This filter is shown in fig. 6 at the extreme right, and is marked with a cross. A longitudinal section of the arrangement is shown in fig. 8. The strainer consists of a basket with a wisp of straw in it (b). This arrests all but the finest particles, and is the best fat-trap I know — the only one, in fact, which does its work efficiently and without offence. The straw may be changed as often as necessary— every day, once a week, once a month, according to the amount of accumulations, which will largely depend upon the thriftiness and knowledge of the cook. The contents of the strainer may be given to the chickens, put on the manure heap, or burnt. A new handful of straw is then put in and the strainer replaced. The changing of the straw has the advantage of giving a new direction to the water. Any old basket of suitable size which will hold the straw answers the purpose of a strainer. After months of use it will get greasy and rotten, and may then be burnt and be replaced by a new one. From the strainer the slops flow into the filter, which is simply a galvanised iron vessel, with an outlet at the bottom and filled with broken clinker varying in size from peas at the bottom to walnuts at the top. This filter effects a further purification of the slops, and acts partly mechanically and partly by virtue of the growth of bacteria, on the surface of the broken clinker. The filter shown has been specially constructed, and is duplicated (see fig. 9), and the waste- 2IO AN EXPERIMENT IN SANITATION pipe of the sink is provided with a reversible nozzle so that either half of the filter can be used. For a cottage, however, this is not necessary, and an old galvanised iron bucket with a hole in the bottom will be found to answer every purpose. The filtration gutter consists of strong cast-iron guttering, perforated with conical holes, having the small ends upwards so that they cannot get jammed {see fig. 10). This guttering, which is 9 inches wide and in lengths of Fig. 9. — Duplicated Tank Filtek. 6 feet, is laid upon loose porous rubble or gravel placed in a trench. A trench 18 inches wide and 18 inches deep was first dug from the filter due south, care being taken that the bottom of the trench should slope away from the cottage, in order that water should not flow back towards the foundations of the building. The lengths of guttering are then laid on a level with the top of the trench, the level being maintained by means of bricks on edge, built FILTRATION GUTTER 211 up without mortar in little columns of four from the bottom of the trench, each column, except the first and last, serving to support the ends df adjacent lengths of -h ^So tier coo t% p 2 212 AN EXPERIMENT IN SANITATION guttering. It being ascertained that the level of the guttering is true, with the slightest possible slope down- ward from the filter, the trench is finally filled with loose rubble of any kind — builders' rubbish, burnt clay, lumps of chalk, gravel, clinker, coke, whatever may be most readily obtained. This arrangement is shown in longitudinal section (fig. 8) and in cross section (fig. 11). Care should be taken that the packing be accurately done at the junctions of the lengths of guttering, in order to give support and firmness to the brick supports. When finished, the filtration gutter looks as though it had been simply laid upon the ground, there being, of course, no indication of the rubble-filled trench beneath it. The iron guttering is sufficiently strong to permit a wheelbarrow or cart to pass over it, and there is no objection to taking the gutter across a path. The sides of the trench should be planted ; or the trench may be dug in a shrubbery or plantation. At the cottage in Gallagher's Copse the trench is taken across the garden, and the sides are planted with raspberries and black currants. The arrangement shown has been in use since September 1900. The straw in the basket has been changed about once a fortnight. The filter has never been changed ; we have never seen the slops run further than the end of the first length of guttering, and when the slops are not running the gutter and its neighbour- hood looks perfectly dry. There is absolutely no smell, no offence to eye or nose. The length of gutter provided is 24 feet (four lengths), but the water has never been seen to travel more than 6 feet. Next, as to expense. The guttering has been made for me by Messrs. Tasker, of the Waterloo Iron Works, Andover, and costs Is. 6cZ. per foot run, and the special FILTRATION GUTTER 213 duplicated slop filter was supplied by the same firm at a cost of 275. 6cZ. The total cost, therefore, of draining this cottage was as under : £ s. d. Labour for digging trench, &c. . .026 Basket 9 Filter 17 6 Four lengths of filtration gutter (24 feet in all) 1 16 Forty-eight old bricks, clinkers, &c., say 10 £3 7 9 But if an old basket and an old galvanised pail be em- ployed, and if two lengths of guttering be used instead of four, then the above bill will be reduced by 2L 6s. 3 0-133 , 0-090 5 2-769 > MEAT 241 This, I believe, should, correctly speaking, be made of the loin muscles of a deer. Biltong made from the ox appears to be equally valuable. With a piece of biltong attached to the saddle, and a knife to cut it, the commissariat department is at once simple and effective. I have met English officers who were loud in praise of biltong as a war ration. In hot dry countries sun-dried uncooked meat is much used by those who spend long hours in the saddle. In a moist climate like England the preservation of dried meats is not to be done without great care. It may be well to direct attention to the fact that certain beasts which feed but seldom, such as snakes, will not eat dead food, but only consume animals which they kill themselves. It is interesting also to observe how domestic carnivora, such as cats and dogs, when burdened with the cares of a family, will often prowl about in search of living prey. When I see my cat incessantly stalking sparrows and making excursions for mice to an inordinate extent, I know that she has a litter of kittens, and I have also observed the same propensity in a brooding bitch. These facts have induced me to carry out some experiments, or rather to ask my friend and former pupil. Dr. Thiele, to carry out some experiments for me, on the relative digestibility of meat under the three conditions in which we know it, viz. : — {a) Immediately after death, before rigor sets in ; (h) during rigor ; and (c) after rigor, when the meat has become tender again. The result of these experiments so far has been to show that m the usual mixture of HCl and pepsin in one and a half hours the ante-rigor meat proves 242 SOME DIETETIC PROBLEMS 25 per cent, more digestible than meat which has entered into rigor. The post-rigor meat is not more digestible than the meat in rigor. The ease with which the muscle fibre undergoes peptonisation before rigor seems to furnish a justification for the conduct of carnivora which hunt their prej. Man very seldom consumes meat before the advent of rigor, never, probably, except when eating oysters. An officer just returned from Africa, who takes a most intelligent interest in these important dietetic questions, told me that he was present on an occasion when some deer got surrounded by a regiment of our men, and were shot down, skinned, and eaten then and there before the onset of rigor. He said they were very good eating, and were much enjoyed as a change from tough draught- ox and ' bully beef.' ^ * In My Mission to Abyssinia, by Gerald Portal, I find the following footnote (p. 188) : " Mansfield Parkyns {Life in Abyssinia, ch. xxvii. vol. i.) gives the following description of ' brundo ' eating. The slaughtering of animals in Abyssinia is attended with a regular ceremony, as in Mohammedan countries. The animal is thrown down with its head to the east, and the knife passed across its throat, while the words ' In the name of the Father, Son, and Holy Ghost ' are pronounced by the butcher. Almost before the death struggles are over persons are ready to flay the carcass, and pieces of the raw meat are cut off and served up before this operation is completed ; in fact, as each part presents itself it is cut off and eaten while yet warm and quivering. In this state it is considered, and justly so, to be very superior in taste to what it is when cold. Eaw meat, if kept a little time, gets tough ; whereas if eaten fresh and warm it is far tenderer than the most tender joint that has been hung a week in England. The taste is, perhaps from imagination, rather disagreeable at first, but far otherwise when one gets accustomed to it." Portal says, "But although we saw nothing of it, Bruce Mansfield Parkyns, Mr. Dufton, and Mr. Kassam all speak of the fondness of the Abyssinians for what they call brundo, i.e. a piece of raw meat cut from the carcass at the very moment when the animal is killed, and eaten probably with the inevitable red-pepper sauce before it has had time to grow cold." RIGOR MORTIS 243 The flesh of the coursed hare is said to be much appreciated by epicures, and the reason given is that rigor has passed off before the animal is eaten. On the other hand, I am told that hunted stag is * horrid to eat,' because *the fat gets all mixed up with the meat in some way.' The contrast between the hunted hare and the hunted stag is, if corroborated, interesting, and seems worthy of attention. I have no personal experience in the matter. The hare is an animal which carries no fat. The chemist can tell us very little as to the difference between muscles in a condition of ante-rigor, rigor, and post-rigor, and yet we find that their solu- bility in digestive fluids differs considerably. We practically never eat meat except in a condition of rigor or post-rigor, when it is relatively indigestible. When a joint of fresh meat is ' hung ' in a pure place, it ripens and gets tender and delicious before putridity sets in. We have no certain knowledge as to the cause of this * ripen- ing,' and one naturally asks, * Is it microbial ? Has the joint of meat served as a cultivating medium for a vegetable growth of which the products are pleasing to the palate?' The ripening of meat does not, if one may judge by the palate, take place in the ice-chest, nor is it possible when it comes out. Some of us are, I think, too ready to judge of the nutritive qualities of food by looking at the chemical analysis. We forget that it is not that which we put into our mouths which nourishes us, but that which we digest and absorb. Digestion depends upon the condition of the diges- tive organs, and these are stimulated to activity by the sensory nerves of the mouth, tongue, palate, nose, and eye. Our appreciations of different kinds of food vary with the individual. In this, as in all other matters, B 2 244 SOME DIETETIC PROBLEMS no two of us are alike. As digestion depends upon the degree to which the flow of secretion from the alimentary tract is stimulated by our sensory nerves, we may fairly conclude that the food which is eaten with appetite and liking is more useful than that which we swallow as a duty, but with loathing, loathing so great that sometimes the stomach instantly rejects its contents. We cannot, happily, get away from that inscrutable craving called appetite — a craving which surely guides the sane man to a selection of food which is suitable for him, and further prompts him to that change of diet which appears to be essential for our well-being. Lind (' A Treatise on the Scurvy,' page 78) says : " Our appetites, if they are not depraved, are upon this and many other occasions the most faithful monitors, and point out the quality of such food as is suited to our digestive organs, and to the state and condition of the body. For where there is a disposition to the scurvy from a long continuance in the moist sea-air, concurring with a glutinous and too solid diet, Nature points out the remedy. In such a situation the ignorant sailor and the learned physician will equally long with the most craving anxiety for green vegetables and the fresh fruits of the earth, from which only relief can be had. Such people, in the height of the disease, not only employ their thoughts all day long in satisfying this importunate demand of Nature, but are apt to have their deluded fancies tantalised in sleep with the agreeable ideas of feasting upon them at {sic) land." Lind, in addition to lemons, fresh vegetables, oranges, pickles, sauerkraut, &c., advocates the use of fresh fermented bread and fermented drinks, such as cider, beer, spruce beer, and wine (such as Malaga SCURVY 245 and home-made wines). Spirits he considers bad for the scurvy, and when used they must have some lemon juice or a slice of lemon added. One of the best remedies is to give lemon with Malaga. Sugar and molasses, added to wine to start fermentation afresh, are advocated. With the growth of our cities, it becomes increasingly difficult to supply their populations with really fresh food. In London we seldom eat fish in really fine condition. The refrigerator enables us to get it free from putrefactive changes, but few Londoners have ever eaten fish in that crisp, curdy condition which it is in when fresh caught. In the present year I have twice visited Newcastle, and have been much struck by the excellence of the fish, due, as I was informed, to the fact that the fishing smacks unload in what is almost the centre of the town. The fish are not only fresh, but new-caught. There is the same kind of difference between fish which have been for days in a refrigerator and new-caught fish that there is between new-laid eggs and * shop ' eggs. The difference between fresh vegetables and those which have been a day or so on a greengrocer's stall is admitted by most of us. Few persons, however, who have not a garden of their own know the flavour of really new-gathered vegetables. Asparagus, peas, beans, and even cabbages which are taken direct from the garden to the pot have a flavour which can and ought to be appreciated. While on the subject of new-gathered food, allusion may be made to the great and deserved popularity of those vegetables which we habitually eat raw, such as ripe fruits, lettuce, endive and other salads, watercress, celery, and, among the poor especially, onions and garlic. How much some of these vegetables lose by cooking 246 SOME DIETETIC PROBLEMS is best seen in the onion, which after cooking is but a shadow of its former self. We must include butter and cheese among the foods which are habitually taken raw, and of whose highly nutritive qualities one can have no doubt. It is obvious that modern cheap substitutes for butter and cheese belong to an entirely different class. I have thus far offered you a good deal of evidence that many foods are more valuable raw than cooked, and more valuable new than old. The nutritive value of a food is proportioned to its digestibility and its power to stimulate appetite and digestive secretions. Apart from such considerations mere chemical analysis is worthless, and I must confess that personally I am in no way converted to the belief that meat which has been refrigerated is at all the equal of new meat which has been hung. Kefrigerator meat is often sold without warning ; and I am rather repelled by joints which are deficient in fat ; in which the cellular tissue shrinks upon the bones, like the jacket of a growing schoolboy on his arms ; in which the first cut some- times lets out a spirt of watery fluid ; in which the fibres gape, and the meat is tasteless, stringy, and flabby, and very often not done in the centre. Such a joint is to a really fresh joint what a * shop egg ' is to one which is new-laid. I am quite ready to admit that refrigerated meat is better than putrid meat; I am aware that there are those who state that it is letter than fresh meat. Nevertheless, I am of opinion that every carcass of meat should bear upon it the date of slaughtering. A week or two since I walked through a village street near London on a Saturday night. The grocers' shops were piled from floor to ceiling THE REFRIGERATOR 247 with tinned provisions ; most of the butchers' shops were hung with joints shiny with moisture or absolutely dripping, showing that they were fresh from the re- frigerator ; and the vendors of fried fish were busy in putting flabby blue sodden -looking stuff into boiling oil, and making a fume which drifted for a quarter of a mile down wind. It is needless to say that a refrigerator is a famous invention for vendors, who are thereby enabled to keep food for a good market, and are never compelled to sell hurriedly at * an alarming sacrifice.' The question whether this old food has the same value as fresh food is one which it is diiBficult to answer, but in the present state of our ignorance there ought to be no risk of our mistaking the one for the other. In the same way * tasteless antiseptics,' such as boric acid, ought not to be added to food unless the fact be clearly stated. It is surely as dangerous to keep a baby too exclusively on pickled milk as it is to keep a sailor too exclusively on pickled pork. We are as yet quite ignorant of the vera causa of the scurvy, which seems to make its appearance when per- sons are deprived oi fresh food. No chemical theory as yet put forward has afforded an adequate explanation. With fresh vegetables, and to a less extent with fresh recently killed meat, scurvy may be warded off, but apparently it is not to be warded off by tinned pro- visions, nor even by lime-juice which has been kept too long.^ ' In the account of the siege of Lucknow, in Recollections of my Life, Sir Joseph Fayrer mentions the intolerable stench from the unburied carcasses of horses, and the insufferable nuisance of flies, and'on page 191 he says : ' One of our greatest wants is that of vegetable food, and the men risk their lives daily to gather the leaves of a wild cruciferous plant growing amongst the ruins ; this is much prized as a green vegetable. Scurvy is prevailing, and the want of this article of diet is severely felt.' 248 SOME DIETETIC PROBLEMS Lind's advocacy of fermented foods, such as beer and bread, is interesting, and that leads me to say that to speak of beer as an * alcoholic ' food, and to gauge its value or the reverse by its percentage of contained alcohol, is a mistake. Beer is the fresh product of a cultivation of a species of saccharomyces in an infusion of malt, just as bread is the production of an allied fungus growing in dough. Alcohol and starch, 'per se, have no antiscorbutic power, but beer and bread, which result from fresh vegetable growths, are both of them credited with the power of keeping off scurvy. In the same way butter and cheese are both of them the products of microbic growth upon certain milk pro- ducts. Cheese is at its best when it is thoroughly ' ripe,' but it must be regarded as fresh food to the end, because it is the ever-growing microbe and its products which really constitute the attractive features of cheese. We have given conventional names to certain pro- ducts without reference to chemistry. Butter is a dairy product which takes some days to make. Attempts have been made to hurry the process by rapidly separating the cream by means of machinery. * Separated ' cream will furnish a very edible grease of uniform quality, but it has never fallen to my lot to eat a really fine sample of butter (judged by flavour) which has been made with * separated ' cream. Nature refuses to be hurried, and it remains to be seen whether the various * ripeners ' {i.e. pure cultivations of microbes) will bestow the true flavour upon * sepa- rated' butter. Margarine has no resemblance on the palate to fresh butter, and is not in any sense a fresh food. To my thinking it is inferior in flavour to good dripping. BUTTER AND CHEESE 249 What is true of butter is true of cheese, and imita- tions of cheese hurriedly made with the aid of fat and chemicals ought to be marked. The ripening of food such as hams, bacon, wine, and even spirits is probably a biological process. Attempts have been made to make * temperance ' drinks without having recourse to fermentation, by arti- ficially * charging ' mixtures of syrup and flavourings with carbonic acid. It is very interesting to see how singularly the attempt has failed, and how in the sum- mer the demand is everywhere for ' stone-bottle ginger beer ' {i.e. fermented) in preference to the imitation article. I lately tasted an imitation ginger beer which was a thin liquor, perfectly brilliant, very sweet, and which made one sneeze. At a guess I thought it was a mixture of water, saccharin, and formic aldehyde charged with carbonic acid. It is singular, but I think true, that liquids which effervesce as the result of fermentation, and those which are * charged ' with carbonic acid, taste quite differently, and, moreover, the effervescence of fermentation is far- more persistent. The practice of * charging ' the cheap effervescent wines and bottled beers is one which ought to be watched. In the same way aerated bread and fer- mented bread cannot be mistaken for each other. From my point of view the former is not * bread ' in the true conventional sense. Baking powders produce an aeration of farinaceous food very different from fermentation, and not acceptable to all of us. The chemist is showing very great ingenuity in imitating Nature, and in furnishing * synthetic products,' which are often made from manufacturers' * waste.' We have a right to demand that these imitation foods 250 SOME DIETETIC PROBLEMS should be clearly labelled. We should then soon arrive at their true market value ; and we must not allow old food, whether refrigerated or pickled, to be sold for new food, and the mixing of chemical products with natural products should be absolutely forbidden unless it be fairly stated on the label. INDEX Abtssinians and meat, 242 Adams, Mr. P., 61 Agriculture, 87, 232 Agriculturists, healthiness of, 94, 170 Airy, Dr., 185 Algerian sheep and anthrax, 19 Analyses of well-water, 129 ; of rain-water, 206 Anaemia, ixodic, of Jamaica, 43 Andover experiment, 126, 168 — garden, 90, 123 — shallow well, 127 — water-supply, 149 Andrewes, Dr., 69 Angell, Lewis, 161 Ankylostoma duodenale, 45, 72, 73 Anthrax, 10 ; cutaneous, 19 ; pul- monary, 20 — and farms, 15 Antiseptics and stools, 166, 174, 198 Appetite, 244 Arrows, poisoned, 6 Arum, the Kew tropical, 75 Ascot enteric fever outbreak, 173 Ash-closets, 180 Atherstone enteric fever outbreak, 187 Bacilluria, enteric, 47 Bacillus anthracis, 10 — coli communis, 47, 80, 153, 163 — enteritides sporogenes, 25, 163 — pyocyaneus, 163 — typhosus, 47, 163, 169 Bacterial treatment of sewage, 162 Baillet, 13 Ballard, Dr., 24, 169, 173, 184, 185, 187, 216 Bangor enteric fever outbreak, 185 Barlow, Sir Thomas, 234 Barming reservoir, 59 Barry, Dr., 185, 186 Battersby, Dr., 41 Beef, 240 ; hung, 240 Beer, 248 Bell, Dr., of Bradford, 17, 19 Bentley, Charles, 73 Beri-beri, 45 Beverley enteric fever outbreak, 140, 185 Bicester enteric fever outbreak, 181 Biltong, 240 ; Professor Halli- burton on, 240 Birth-rate, diminished, 134 Blackburn enteric fever outbreak, 185 Blandford, 42 Blaxall, Dr., 144, 147, 184 Boarley water system, 67 Bodmin enteric fever outbreak, 185 Boers and biltong, 240 Boobbyer, Dr., 74 Bouley, 13 Bovine tuberculosis, 228 Bowden, 41 Bruce, 29 Buchanan, Sir George, 146, 171, 183 Buckingham enteric fever out- break, 186 Building, 201 252 INDEX Burial of faeces, 192 Burrows, 82 Butter, 248 Caius, Dr., 237 Caius College enteric fever out- break, 146 Cameron, Sir Charles, 50 Cameron, Dr. Macmartin, 78 Camps, sanitation of, 189 Cancer, 45 Carnivora and living prey, 241 Carrington Moss, 116, 117 Carver, Dr. J. E., 47 Castellote, Dr., 41 Caterham enteric fever outbreak, 139 Cemeteries, 57, 228 Cesspools, 161 Chamberland, Dr., 9 Charbon, 9 Charging with carbonic acid, 249 Chat moss, 116 Chauveau, Dr., 19 Cheadle, Dr., 234 Cheese, 248 Chester-le- Street enteric fever out- break, 187 Chichester enteric fever epidemic, 63 Childs, Dr., 50 Chinese, 83, 89 Cholera, 28, 161, 175 Cisterns, 150 Cities, 170 Cleanliness of Dutch, 110 ; of Gro- ningen, 107; of West-end of Lon- don, 125 Closet-pails, weight of, 108, 109 Clowes, Dr., 162 Colin, Dr., 13 Copeman, Dr., 24, 37 Corfield, Professor, 56 Corn laws and typhus, 159 Cottage, building a, 203 Cows, 238 ; and tuberculosis, 223 Crookes, Sir William, 99 Crosse, 40 Cutting off the water, 152 Daibies and enteric fever, 217 Darwin, 80 Davaine, 10, 13 ^ Davidson, Professor Andrew, 26, 27 Davy, J. S., 58 Death-rate in Groningen and Friesland, 109 ; in Holland, 105 ; of tabes mesenterica, 224 Dempster, 88 Dental caries, 234 Dewsbury district enteric fever out- break, 184 Diarrhoea, 21 ; mortality of, 22, 23, 161 Dietetic problems, 231 Digestion, 243 Diphtheria, 34 Dirty habits, 180, 182 Disinfection of linen, 155 ; of stools, 156 Dubois, Abb6, on Hindu manners, 71 Dung, 89, 96, 103, 133 Durham, Dr., 42, 60 Dutch, the, 104, 110 Dutch cleanliness, 110 Dysentery, 26 Eaeth, 1 Earth, the, as a filter, 78 Earth and anthrax, 13, 18 Earth-closet, 213 Earthworms, 12, 80, 81 Edington, Dr., 44 Elliott, Eobert, 103 Enfield enteric fever outbreak, 184 Enteric fever, 46, 85, 135 ; death rates, 177 ; in Holland, 106, 109 110 ; and milk, 173 ; and over crowding, 177 — — outbreaks : Ascot, 173 Ather stone, Warwick, 187 ; Ban gor, 185 ; Beverley, 140, 185 Bicester, 181 ; Blackburn, 185 Bodmin, 185 ; Buckingham, 186 Caius College, 146 ; Caterham 139; Chester-le -Street, 187 Dewsbury, 184 ; Enfield, 184 Faldingworth, 185 ; Guildford 139, 183 ; Haverfordwest, 184 High Wycombe, 171 ; Hitchin 140, 185; Houghton-le- Spring, 141 ; Islington, 216 ; Kidder INDEX 253 minster, 185 ; King's Lynn, 186 ; Lewes, 184 ; Llanelly, 184 ; Long- ton, Staffs, 186 ; Maidstone, 58, 80; Margate, 140, 185; Mary- lebone, 173 ; Masborough, 186 ; Middlesbrough, 178 ; Mountain Ash, 145; Newark, 186; Newlyn East, 185 ; Newport, Isle of Wight, 140, 187 ; Okehampton, 184 ; Parkhurst Barracks Prison, 187 ; Red Hill, 139 ; Eaunds, Northants, 188 ; Eawmarsh, 186 ; Rochester, 186 ; Rotherham, 186 ; Sandown, 184 ; Sheerness, 185 : Tees Valley, 186 ; Tideswell, 184 ; Totnes, 185 ; Warwick, 183 ; West Cowes, 184 ; Worthing, 140, 148, 187 ; Ventnor, 184 — stools and water, 157 Ewell, 62 Excreta, disposal of human, 90 (see also Groningen) Experiments, agricultural, of Sir John Bennett Lawes and Sir Henry Gilbert, 96, 97, 98 Exports from Holland, 112, 113 F.ECAL matter, application of, to land (see Andover, Carrington Moss, Groningen, Manchester) , how to deal with : Andover garden, 126 ; Groningen method, 108 ; Manchester (see Carrington Moss) Falding worth enteric fever out- break, 185 Farleigh springs, 59 Farms and anthrax, 15 Farmyard manure, 96 Farr, Dr. William, 161 Fauna of death, 190 Fayrer, Sir Joseph, 39, 247 Feeding of infants, 226, 236, 237 Fermented foods and drinks, 244 Fermes a charbon, 10 Fertility, maintenance of, of soil, 96 Filter, duplicated tank, 210 Filtration gutter, 210, 211, 212 Fish, 245 Flies, 77, 189, 247 Food and antiseptics, 239, 250 Food and chemical analysis, 243 Food-supply, 91, 99, 230 Foulerton, Mr., 60 Frieberger and Frohner, 6, 15, 44 Frohner (see Friedberger) Fungi and dung, 5 Gaertner's bacillus, 47 Gainsborough and enteric fever, 175 Gallagher's Copse, 201 Gases, 75 Gelatinous foods and bacteria, 169 Gepp, Mr. A., 90 Gibson, Mr. Maitland, 48 Gilbert, Sir Henry, 96, 101 Glasgow enteric fever death-rate, 142 Graves and anthrax, 11, 13, 17 Gresswell, Dr., 185 Groningen, 107 ; collection of feecal matter in, 107 Ground-itch, 73 Guerin, Alphonse, 13 Guildford enteric fever epidemic, 139, 183 Haden, Sir Seymour, 198 Heematozoa of malaria, 38 ; of tsetse-fly disease, 42 Hamburg beef, 240 Hare, the flesh of coursed, 243 Hart, Mr. Ernest, 28 Harvest, influence of, on soil, 81 Haverfordwest enteric fever out- break, 184 Hayes, Captain, 7, 44 High Wycombe enteric fever out- break, 171 Hindu manners, 71 Hitchin enteric fever outbreak, 140, 185 Holland, mortality statistics of, 105, 106 — sanitation in, 104 Holt, Chief Justice, 161 Holt Town works, 124 Hong-Kong plague, 33 Hop gardens, 81 254 INDEX Horse disease, or African horse- sickness, 44 Horses in St. Domingo and teta- nus, 26 Horse-dung and diarrhoea, 26 Houghton-le- Spring enteric fever outbreak, 141 House cisterns, 50 Houston, Dr., 3, 162, 207 Humification, 166 Humus, 1 Hung beef, 240 Hydatids, 45 Hyde, Dr. Samuel, 90 Immunity, 69 — of Algerian sheep to anthrax, 19 Imports from Holland, 112 Infant mortality, 134 Insects and wells, 127 Insuction by leaking water-pipes, 143 ; when direct connection with main, 145 Intermission of water-supply and enteric fever, 143 Isleworth cottage, 174 Islington milk enteric fever epi- demic, 216 Ixodes bovis, 43 Jameson, Director-General, 73 Jenner, Sir William, 159 Jones, Dr., of Chichester, 53 Joubert, 12 Kanthack, 28, 42 Kidderminster enteric fever out- break, 185 King's Lynn enteric fever outbreak, 186 Kitchen refuse, 197 — sinks, 150, 210 Kitasato, Professor, 5 Klein, Professor, 25, 26 Koch, Professor Eobert, 10, 11, 175 Koch's vibrio, 28 Lamb, Charles, 231 Laveran, 39 Lawes, Sir John Bennett, 96, 101, 102, 103 Le Dantec, 6 Leeu warden, 107, 109, 113 Lewes enteric fever outbreak, 184 Liebig, 100 Lind on scurvy, 244, 248 Linen, disinfection of, 155 Lingard, 42 Linnaeus, 189 Lister, Lord, 87, 229 Llanelly enteric fever outbreak, 184 Local Government Board, 143 Loesener, 56 Longton, Staffs, enteric fever epi- demic, 186 Louping ill, 43 Low, Dr. Bruce, 175, 178, 186, 188 Lowson, 33 Maclean, 39, 73 Maidstone barracks and prison, 67 Maidstone enteric fever epidemic, 58, 80, 148, 228 Mai de montagnes, 10 Malaria, 38 Malignant pustule, 19 Malta fever, 29 Manchester cleansing, 116, 123 Manson, Dr. Patrick, 40 Marchesi, 8 Margarine, 248 Margate enteric fever outbreak, 140, 185 Martin, Dr. Sidney, 46, 47, 50, 88, 169 Marylebone milk enteric fever epi- demic, 173 Masborough enteric fever outbreak, 186 McConnell, Mr., 117 Meat, 240 ; relative digestibility of, 241 ; Thiele's, Dr., experiments, 241 ; value of raw, 240, 242 Meek, 43 M6gnin, 190 Microbes, 3 Micrococcus melitensis, 29 Micro-organism of diphtheria, 34 Middens, 179 INDEX 255 Middlesbrough and enteric fever, 178 Milk, 216, 235 ; and tabes mesen- terica, 220 ; and tuberculosis, 219 ; and water supplies, 152 Milroy lectures, 1 Model by-laws, 181, 201, 204 Montagues dangerenses, 13 Moorland waters, 142 Mortality tables, 92, 93, 226 Moses, 199 Mountain Ash enteric fever out- break, 145 Munich and enteric fever, 51 Murchison, Dr., 177, 181 Murray, Mr. George, 5 Mushrooms, common, 4 Newark enteric fever epidemic, 186 Newlyn East, Cornwall, enteric fever outbreak, 185 Newport, Isle of Wight, enteric fever outbreak, 140, 187 Newsholme, Dr. Arthur, 34 Nitrification, 85 Odours, 75 (Edema mycosis, 44 Okehampton enteric fever epi- demic, 184 Old-age pensions, 95 Organisms, pathogenic, 3 Osier, Dr., 39, 47 Overcrowding and enteric fever, 177 Packard, 190 Page, Dr. Davis, 141, 185 Pails, closet, 108, 109 Parkhurst barracks prison enteric fever outbreak, 187 Parsons, Dr., 184, 185, 186 Pasteur, 9, 10, 11, 12, 14, 18, 78 Pathogenic bacteria in interred corpses, viability of, 56 Pathogenic organisms, 3 Paving, impermeable, 170 Payne, Dr. J. F., 30 Pepys, 237 Pettenkofer, 28, 50 Phthisis in milk trades, 224 Pictet and Yung, 21 Plague, 30, 76 Plant roots, as tillers of soil, 103 Plumbers, registration of, 155 Polluted soil, 169 Pollution of water, 161 ; of wells, 174 Portal, Mr. Gerald, 242 Post-mortem room sinks, 150 Power, Mr. W. H., 185 Poynton and Paine, Drs., 35 Practical considerations, 78 Privies, 160 Public authorities and water-sup- plies, 154 Babbits, 82, 84 Eadcliffe, Mr. N., 173 Rainfall and Maidstone enteric fever epidemic, 64 Rain-water tank, 204 Rats, 82, 84 Rats and plague, 32 Raunds, Northants, enteric fever outbreak, 188 Rawmarsh enteric fever outbreak, 186 Rayer, 10 Redhill enteric fever outbreak, 139 Rees, 40 Refrigerated meat, 246 Refuse in Groningen, 107; on Salisbury Plain, 196 Registration of plumbers, 155 Rickets, 234 Rigor mortis, 242 Rivers, 142 ; pollution of, 161 ; law against pollution of, 161 Robertson, Dr. John, 48, 49, 54, 89 Rochester enteric fever outbreak, 186 Rothampstead experiments, 96, 97, 98, 101, 102, 103 Rotherham enteric fever outbreak, 186 Ross, 39 Rotiget, 6 Botiget du pore, 57 256 INDEX Salisbury Plain, 191 Sandown enteric fever outbreak, 184 Sanitary methods of our ancestors, 160 Sanitation, of camps, 189 ; an experiment in, 201 ; in Holland, 104 Saprophytes, 3 ; classification of, 4 ; oxygen and, 4 Scavenging, of camps, 191 ; in Groningen, 107, 114; of Man- chester, 118 Schmidt-Muhlheim, 17 Scurfield of Sunderland, 50 Scurvy, 229, 244, 247 Sewage, bacterial treatment of, 162 Sewage farms, 171 Sewer gas, 161 Sewer pipes, leaking, 143, 162 Sewer pipes and water-pipes, 143, 144 Sewers and storm-water, 149 Sheerness enteric fever outbreak, 185 Sherborne enteric fever outbreak, 147 Simon, Sir John, 183, 184 Slaughtering of animals in Abys- sinia, 242 Slop-water, 160, 161, 207 Smallpox and tramps, 45 Smith, Dr. Greig, 43 Snow, Dr., of Buffalo, 24 Soil, 1 Spear, Mr. John, 145, 185, 186 Spencer, Dr. Herbert, 236 Springs, 84, 142 Stag, flesh of hunted, 243 Stanley, Sir H. M., 6 Stewart, Professor Hunter, 79 Stings of insects, 41 Stinks, 75 Stockman, Professor Stewart, 75 Stools, disinfection of, 156 Stools, enteric, and water, 157 Stools and tillage, 165 Storm overflows, 149 Strainer for slop-water, 207, 208 Street refuse, 8 Street sweeping, 108 Streptococci, 163 Stuart, Mr. Verryn, 106 Surra, 42 Survival of the unfittest, 170 Swine erysipelas, 57 Swine fever, 45 Synthetic products, 249 Tabes mesenterica, 220 Takaki, Dr., 33 Tank, rain-water, 204 Tatham, Dr., 93, 224 Tees Valley enteric fever outbreak, 186 Temperance drinks, 249 Tetanus, 5 ; bacillus, 5 ; and market gardeners, 6 ; pastures, 7 Tew, 60 Texas fever of cattle, 43 Thames and sewage, 159 Thiele, Dr., 241 Thomson, Dr. T., 58, 181, 186, 187 Thorne, Sir Bichard, 46, 55, 139, 169, 172, 184, 219 Threadworms, 45 Thresh, Dr., 150 Thyroid gland, 239 Tick-birds, black, of Jamaica, 43, 44 Tick fever, Australian, 43 Ticks, 43 Tideswell enteric fever outbreak, 184 Tillage, 165, 195 Tinned provisions, 247 Tomaselli, 29 Tomkins of Leicester, 24 Tooth, Dr. H. H., 189 Totnes enteric fever outbreak, 185 Tramps and enteric fever, 85 ; and small-pox, 45 Trees, dead, 82 Trenches, 193 Trypanosoma, 42 Tsetse fly disease, 42 Tubercle, 74 Tuberculosis, 219 Tuberculous birds, 75 Tutsham-in-Field, 59, 60, 61 Tutsham-in-Orchard, 62 Typhoid and typhus, 159 INDEX 257 Typhus, 69, 70 ; and corn laws, 159 ; and typhoid, 159 University College Hospital and disinfection of linen, 155 Upland water, pollution of, 142 Urine and humus, 167 VAILIiARD, Dr., 6 Vegetables, 245 Venetian cistern, 204 Ventnor enteric fever outbreak, 184 Verminous, the, person, 45 Vienna plague cases, 31, 32 Villar, Mr. Sidney, 7 Villemin, 13 Vincent, Dr., 6 Warington, 3 Warwick enteric fever outbreak, 183 Washbourn, Dr., 60 Waste of manure, 100 ; of water, 155 Water, boiled, 83 Water-closets, 105, 107, 161, 169 Water companies, 154 ; and watei* examination, 152 Watercress beds, 158 Water-pipes, burst, 144 ; and sewer- pipes, 143, 144 Water-supplies, pollution of public, 136, 137 ; and milk, 152 ; and public authorities, 154 Water-supply, 151 ; and dairies, 218 Wells, 154, 174 ; pollution of, 139, 140, 141, 158 — shallow, 78, 84, 127 ; and in- sects, 127 — village, 79 Well water, analyses of, 129 West Cowes enteric fever outbreak, 184 Wheaton, Dr., 171, 286 Willcocks, Dr. G. 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