TEXT-BOOK OF HYGIENE A COMPREHENSIVE TREATISE Principles and Practice of Preventive Medicine FROM AN AMERICAN STAND-POINT. QKORQE H. ROHK, M.D., PROFESSOR OF THERAPEUTICS, HYGIENE, AND MENTAL DISEASES IN THE COLLEGE OF PHYSICIANS AND SURGEONS, BALTIMORE; SUPERINTENDENT OF THE MARYLAND HOSPITAL FOR THE INSANE; MEMBER or THE AMERICAN PUBLIC HEALTH ASSOCIATION; FOREIGN ASSOCIATE OF THE FRANCAISE D'HYGIENB, KTC. THIIP5.D THOROUGHLY REVISED AND LARGELY REWRITTEN, WITH MANY ILLUSTRATIONS AND VALUABLE TABLES. PHILADELPHIA : THE F. A. DAVIS COMPANY, PUBLISHERS. LONDON : F. J. REBMAK 1895. COPYRIGHT, 1891, BY F. A. DAVIS. COPYRIGHT, 1894, BY THE F. A. DAVIS COMPANY. [Registered at Stationers' Hall, London, Eng.j Philadelphia, Pa., U. S. A. : The Medical Bulletin Printing-House, 1916 Cherry Street. TO HENRY INGERSOLL BOWDITCH, A.M., M.D., IN THE FIELD OF (iii) PREFACE TO THE FIRST EDITION. THE aim of the author in writing this book has been to place in the hands of the American student, practitioner, and sanitary officer, a trustworthy guide to the principles and practice of preventive medicine. He has endeavored to gather within its covers the essen- tial facts upon which the art of preserving health is based, and to present these to the reader in clear and easily understood language. The author cannot flatter himself that much in the volume is new. He hopes nothing in it is untrue. (v) PREFACE TO THE THIRD EDITION. IN this edition every chapter has been subjected to a careful revision, and the advances in sanitary science and practice have been incorporated. Recent legislation in the United States and Canada has almost revolutionized quarantine practice. Surgeon-General Walter Wyman, and Dr. H. D. Geddings, of the United States Marine-Hospital Service, have, at the request of the author, entirely rewritten the chapter upon Quarantine, and it will be found to represent fully the modern principles and practice of maritime sanitation. Medical Director Albert L. Gihon, United States Navy, has again thoroughly revised the chapter on Marine Hygiene. With the view of making the book still more useful to teachers, students, and sanitary officers than heretofore, an ana- lytical set of questions has been appended to each chapter, and a separate section has been added on methods of examination of air, water, and food. For these additions the author is indebted to Professor Seneca Egbert, of Philadelphia. Dr. Egbert has also carefully revised the chapter on Vital Statistics. The author desires to thank all who have assisted him in the work, and especially the sanitarians throughout the country who have been helpful in the way of criticism and suggestion. He hopes that the new edition will merit, as well as receive, the approval of all students of Preventive Medicine. BALTIMORE, MD., October, 1894. (Vii) CONTENTS. CHAPTER I. PAGE ....... 1 CHAPTER II. WATER, . . . . 49 CHAPTER III. FOOD, ... . . ^ ,. 87 CHAPTER IV. SOIL, . . J3H"' - ' - . . 131 CHAPTER V. REMOVAL OF SEWAGE, . . . . . . . . . 147 CHAPTER VI. CONSTRUCTION OF HABITATIONS, 165 CHAPTER VII. CONSTRUCTION OF HOSPITALS, 195 CHAPTER VIII. SCHOOL HYGIENE, 207 CHAPTER IX. INDUSTRIAL HYGIENE, 223 CHAPTER X. MILITARY AND CAMP HYGIENE, ....... 249 CHAPTER XI. MARINE HYGIENE, 261 CHAPTER XII. PRISON HYGIENE, 279 (ix) X CONTENTS. CHAPTER XIII. PAGE EXERCISE ANIT TRAINING, 285 CHAPTER XIV. BATHS AND BATHING, 293 CHAPTER XV. CLOTHING, . . . 301 CHAPTER XVI. DISPOSAL OF THE DEAD, 307 CHAPTER XVII. THE GERM THEORY OF DISEASE, 313 CHAPTER XVIII. CONTAGION AND INFECTION, 319 CHAPTER XIX. HISTORY OF EPIDEMIC DISEASES, 325 CHAPTER XX. ANTISEPTICS, DISINFECTANTS, AND DEODORANTS, .... 387 CHAPTER XXL VITAL STATISTICS, 401 CHAPTER XXII. THE EXAMINATION OF AIR, WATER, AND FOOD, .... 413 CHAPTER XXIII. QUARANTINE, 441 INDEX, 547 TEXT-BOOK OF HYGIENE. CHAPTER L AIR. EXACT investigation into the influence of the atmosphere upon health is yet in its infancy. Enough has been learned, however, to show that changes in the composition of the air, in its density, its temperature, its humidity, its rate and direction of motion, and possibly its electrical or magnetic conditions, influence in various ways the health of the individual. It is only very recently that any scientific attempts have been made to trace the bearing of atmospheric changes upon health. The observations already recorded indicate that a thorough study of meteorological phenomena in connection with the origin and progress of certain diseases is a promising field of labor ibr the educated sanitarian. The meteorological observations which have been gathered by the United States Signal Service during the past twenty-three years, together with elaborate studies made by the meteorologists and climatologists of other countries, already form such a large and tolerably complete and well- arranged body of facts, that reasonably accurate deductions can even now be made. Heretofore, in studying the sanitary rela- tions of the atmosphere, both in this country and abroad, the attention of observers has been riveted almost exclusively upon the changes in its composition occurring within certain limited areas. It is, perhaps, equally important to study this universally diffused and necessary condition of vital activity in its broader and more general relations. It will be shown, in the course of the present work, that the meteorological features of countries, CD 2 TEXT-BOOK OF HYGIENE. or of seasons, or even the daily atmospheric changes, exercise an important influence upon life and health. In order to fully appreciate these relations it will be necessary to first give a brief summary of the facts and laws of meteorology. THE COMPOSITION AND PHYSICAL CONDITIONS OF THE ATMOSPHERE. Atmospheric air is a mixture of four-fifths of nitrogen and one-fifth of oxygen; more accurately, 79.00 of the former to 20.96 of the latter. In addition, there is constantly present a modicum of carbon dioxide, usually a little over .03 per cent. (3 to 4 parts in 10,000), traces of ammonia and nitric acid, and a variable proportion of vapor of water. These proportions are maintained, with but very little change, at different heights. At first thought, it would seem that carbon dioxide, being much heavier than the other con- stituents of air, would accumulate in the lower regions of the atmosphere, and there cause an excess of this poisonous con- stituent, but in obedience to the law of diffusion the interming- ling of the component gases is perfect, and the proportion of carbon dioxide in the atmosphere is quite as great on mountain- tops as in the deepest valleys. The proportion of nitrogen in atmospheric air is generally uniform, while that of oxygen varies, depending to a great ex- tent upon the. amount of carbon dioxide present. Hence, an increase in the amount of the latter constituent is usually ac- companied by a diminution of oxygen, inasmuch as the formation of carbon dioxide can only take place at the expense of oxygen. The reciprocal activities of animal and vegetable life are beauti- fully illustrated by these relations between the oxygen and carbon dioxide in the air. In the processes of combustion and oxidation, oxygen is withdrawn from the atmosphere, and com- bines with carbon, forming carbon dioxide. During vegetable growth, on the other hand, carbon dioxide is withdrawn from the air by the leaves of plants, and decomposed into its elements, carbon and oxygen. The carbon is used in building up the COMPOSITION AND PHYSICAL CONDITIONS OF ATMOSPHERE. 3 plant, while the liberated oxygen is restored to the atmosphere. The animal consumes oxygen, and gives out carbon dioxide; the plant resolves this compound into its constituent elements, and gives back the oxygen to the air again. Some recent experiments of Jolly have shown that on days of northerly winds the proportion of oxygen is higher than the average, while under the influence of the south wind the propor- tion of oxygen is deficient. The extremes in a series of 21 observations were 21.01 and 20.53 per cent. The difference, .48 per cent., is too small to have any appreciable influence upon health. The atmosphere extends upward from the surface of the earth to an indefinite distance. The limit has been variously placed at from 75 kilometres to 40,000 kilometres. For all sanitary purposes the former may be taken as the upward limit of the atmosphere. In obedience, to the law of gravity, this mass of air everywhere presses directly downward toward the earth's centre with a force equal to its weight. If a column of this air be balanced by a column or mass of any other matter the columns being of the same diameter we have a relative measure of the weight of the atmosphere. The instrument with which the weight or downward pressure of the air is measured is called a barometer. The atmosphere, at the sea-level, presses downward with a force equal to' the pressure of a column of mercury 760 millimetres high. Hence, the barometric pressure at sea-level is said to be 760 millimetres, or 30 inches. If the barometer be carried to the summit of a mountain 1000 metres above the level of the sea, or taken to the same altitude in a balloon, the mercury in the barometer- tube will fall about 90 millimetres. These 90 millimetres of the mercurial column represent the weight of 1000 metres of air now below the barometer, and consequently not measured or balanced by it. 1 Upon ascending from the sea-level, it is found also that the 1 The figures here given are not absolute, but merely approximate. The limits of this work do not allow a full discussion of the meteorological elements modifying the pressure of the atmosphere at sea-leveL 4 TEXT-BOOK OF HYGIENE. air, being less pressed upon by that which is still above it, becomes more rarefied and lighter; its tension, as it is termed, is less. Hence, for the second 1000 metres of ascent above the sea, the mercury will fall a less distance in the tube, the weight removed not being so great as in the first 1000 metres. The following table shows the diminution in atmospheric pressure for every 1000 metres above sea-level: TABLE I. Height. Barometric Pressure. Sea-level, 760.0 millimetres. 1,000 metres, 670.4 " 2,000 " 591.5 " 3,000 " 521.0 " 4,000 " 460.3 " 5,000 " 406.0 " 6,000 " 358.2 " 7,000 " . . . 316.0 " 8,000 " . . . . . . 278.8 " 9,000 " 245.9 " 10,000 " 216.9 " 11,000 " 191.1 " 12,000 " 168.8 " 15,000 " 115.9 " 20,000 " 61.9 :; Variations in temperature and humidity of the air influence the tension of the atmosphere in a marked degree, and affect the height of the barometric column. In fact, most of the changes of atmospheric pressure at the surface of the earth are directly due to changes in temperature and humidity. Increase of temperature diminishes the density of the air. Hence, when the temperature rises the pressure decreases. The proportion of moisture (aqueous vapor), if increased, likewise causes a diminution in pressure. It is found, for ex- ample, that when the amount of aqueous vapor in the air increases the barometer falls. This is due to the fact that the specific gravity of aqueous vapor is less than that of dry air, being in the proportion of .623 to 1.000. Hence, as aqueous COMPOSITION AND PHYSICAL CONDITIONS OF ATMOSPHERE. 5 vapor is diffused through air, the latter becomes lighter, or, in other words, the barometric pressure diminishes. The warmth of the air is primarily derived from the sun. On a clear day about one-fourth of the heat of the sun's rays is given off directly to the air during the passage of the heat- rays to the earth. Of the remaining three-fourths, part is re- flected from the earth, while the larger portion is first absorbed by the earth, and then given off by radiation and convection to the superincumbent air. The air is always warmer near the earth's surface on a clear, sun-shiny day; for, as soon as the earth gets warmer than the air immediately above it, the excess of heat is given off to the latter by convection and radiation. On ascending from the surface of the earth the temperature decreases, and on the summit of a high mountain the air is always colder than at its base. Professor Tyndall has shown that dry air absorbs less heat than air which is charged with vapor. For this reason the sun's rays strike the earth with much greater intensity on a very dry than on a moist day, while on the latter a larger proportion of the heat-rays is intercepted before they reach the earth. Recent experiments seem to show, however, that the differ- ence in diathermancy between dry and humid air is not so great as supposed by Tyndall. The depth of the air-stratum, through which the sun's rays pass, is of greater influence than the humidity. Air, at different temperatures, is capable of absorbing different amounts of aqueous vapor. Thus, air at a temperature of 4 will require a much smaller amount of vapor to produce saturation than air at a temperature of 30. For this reason air which appears " damp " at the former temperature, both to the bodily sensations and to appropriate instruments, would be considered as "dry" at the latter temperature, although the actual amount of vapor present, or absolute humidity, is the TEXT-BOOK OF HYGIENE. same in both cases. 1 In meteorological observations for sanitary purposes, the relative humidity is the condition deserving especially careful study. It must be borne in mind that the mere statement of the percentage of relative humidity, without taking into account the temperature of the air, is of little significance. A like remark is justified with regard to statements of absolute humidity, when used to illustrate the apparent effects of atmospheric moisture upon life and health. The following table shows the absolute humidity corre- sponding to the same relative humidity at different tempera- tures. It also includes the total possible absolute humidity and the difference between the actual and possible humidity (deficiency of saturation) at the temperatures given : TABLE II. Tempera- ture C. Relative Humidity (per cent.). Absolute Humidity (grammes per cubic metre). Greatest Possible Absolute Humidity. Deficiency of Saturation. 20 60 0.638 1.064 0.426 10 60 1.380 2.300 0.920 60 2.924 4.874 1.950 +10 20 60 60 5.623 10.298 9.372 17.164 3.749 6.866 30 60 18.083 30.139 12.056 In forests the relative humidity is usually higher than over unwooded districts, although the absolute humidity may be the same, or, perhaps, even less. The evaporation is usually much greater in the open air than in forests. In closed apartments the evaporation may be greater or less than in the open air, de- pending upon the local conditions present. 1 By "absolute humidity" is meant the total amount of vapor present in a certain mass of air. By the term "relative humidity " meteorologists designate the proportion of vapor present at certain temperatures, compared with full saturation of the air with vapor, which is reckoned 100. Thus, air which is saturated, or whose relative humidity is 100 at 4, would have a relative humidity of only 24, if the temperature were raised to 27, because in the latter case the capacity of the air for aqueous vapor is increased. Relative humidity is always designated in percentages ; absolute humidity in grammes per cubic metre or grains per cubic foot. COMPOSITION AND PHYSICAL CONDITIONS OF ATMOSPHERE. 7 The motion of the air wind is caused by differences in pressure ; the latter being due to differences in temperature and humidity. A mass of air traversing a large body of water absorbs vapor, unless already saturated, and becomes moist ; if it pass over a wide tract of dry land it loses moisture and becomes dry. Therefore in the eastern portion of the American continent, an easterly or southerly wind, which comes from over large bodies of water, and which is usually warm, and thus capable of hold- ing a large quantity of water in a state of vapor, is always moist. On the other hand, a northerly or westerly wind, com- ing over a large extent of dry land, and from a colder region, is nearly always a dry wind. On the Pacific coast these condi- tions are reversed ; there a westerly wind is a moist wind, while an easterly wind is dry. The dreaded easterly wind of England is likewise a dry wind. It is probable that the direction and rate of motion of air-currents have considerable influence upon the origin or intensification of certain diseases. The electrical and magnetic conditions of the atmosphere have been as yet studied to little advantage. It is only known that atmospheric electricity is, in most cases, positive, and that its intensity increases with condensation of vapor. There seems to be no doubt that the varying states of atmospheric electricity are closely connected with evaporation and condensation. There is reason to believe that a fuller knowledge on these topics will yield most important results to the student of hygiene. Ozone and antozone, or hydrogen peroxide, are usually present in the atmosphere in varying proportions. Careful and extended observations have failed to show any connection be- tween the presence of these agents in the atmosphere and modi- fications of health. It is probable that the sanitary importance of ozone and of hydrogen peroxide have been much overrated. It is not known that either of these substances has any other function in the atmosphere than that of an oxidizing agent. The sanitarian should be a practical meteorologist. In addition to a knowledge of the principles of the science, he 8 TEXT-BOOK OF HYGIENE. should possess the skill to make accurate observations of me- teorological conditions, and estimate their significance. But the acquisition of an elaborate collection of instruments, and their regular observation, is too expensive and time-consuming. A German physicist, Lambrecht, has de- vised an instrument which combines in itself nearly all the requirements of a trustworthy meteorological instrument (Fig. 1). This instrument is called a polymeter, and shows, on easily-readable scales, the temperature, relative humid- ity, dew-point, absolute humidity in grammes per cubic metre, and vapor tension. INFLUENCE OF CHANGES OF ATMOSPHERIC PRESSURE ON HEALTH. The effects of a considerable dimi- nution of pressure are familiar to every one in the " mountain sickness " which attacks most persons on ascending high mountains. M. Bert has shown experi- mentally that similar effects can be produced in an air-tight chamber by diminishing the pressure. 1 The symp- toms produced under a pressure equiva- lent to an altitude of from 4000 metres to 5000 metres were a feeling of heavi- ness, nausea, ocular fatigue, rapidity of pulse, convulsive trembling on slight exertion, and a sensation of languor and general indifference to the surroundings of the individual. M. Lortet, who has left on record his experiences in the higher Alps, says that the symptoms noticed on ascending to 1 Popular Science Monthly, v, p. 379. FIG. 1. IjAMBRECHT'S POL.YMETER. INFLUENCE OF CHANGES OF ATMOSPHERIC PRESSURE. 9 high altitudes are: Labored respiration, increased rapidity of pulse, depression of temperature (as much as 4 to 7 C.). The normal temperature was restored, however, after a brief rest. 1 Still more severe symptoms have been noticed on ascending high mountains in South America and Asia. Aeronauts have lost consciousness, and in several instances life, on rapidly ascending to great altitudes. 2 According to the observations of the brothers Schlagintweit, distinguished explorers of the highlands of Asia, the effects of diminished pressure upon the human organism are : " Headache, difficulty of respiration, and affec- tions of the lungs, the latter even proceeding so far as to occasion blood-spitting, want of appetite, and even nausea, muscular weakness, and a general depression and lowness of spirits. All these symptoms, however, disappear in a healthy man almost simultaneously with his return to lower regions." A singular observation was made by these travelers on the effect of motion of the air upon the symptoms described. They say: " The effects here mentioned were not sensibly increased by cold, but the wind had a most decided influence for the worse upon the feelings When occupied with observa- tions, we took very little, if any, bodily exercise, sometimes for thirty-six hours ; it would frequently occur nevertheless, even in heights not reaching 17,000 feet (about 5150 metres), that an afternoon or evening wind would make us all so sick as to take away every inclination for food. No dinner was cooked; the next morning, when the wind had subsided, the appetite was better. " The effects of diminished pressure are considerably aggra- vated by fatigue. It is surprising to what degree it is possible for exhaustion to supervene ; even the act of speaking is felt to be a labor, and one gets as careless of comfort as of danger. Many a time our people those who ought to have served us as guides would throw themselves down upon the snow, declaring 1 Realencyclopaedie d. ges. Heilk., v., p. 529. 2 MM. Sivelan:! frocr-Spindli, two aeronauts, lost their lives in this manner during an ascent from Paris, in April. 1875. 10 TEXT-BOOK OF HYGIENE. they would rather die upon the spot than proceed a step farther." 1 These symptoms disappear when persons are exposed to these conditions for a prolonged time. Thus, in the Andes there are places 4000 metres above sea-level which are per- manently inhabited ; and in the Himalayas there are villages at a height of over 5000 metres constantly occupied. In this country, Pike's Peak, 4350 metres above the sea, has been occupied since 1873 by observers of the signal service. The men seem to become acclimated, as it were, and suffer little or no inconvenience from the diminished pressure after a time. The minor disturbances of healthy function produced by diminished pressure (within the limits of 4000 metres altitude, or 460 millimetres barometric pressure) are an increase in the pulse and respiration rate. This is probably due to the struggle of the organism to take up the required quantity of oxygen which is reduced in proportion by the rarefaction of the air. For example, the proportion of oxygen at a pressure of 460 millimetres would be equivalent to 12.6 per cent, at sea-level, instead of the normal 20.9 per cent. Paul Bert has shown by personal experiments in the pneumatic chamber that the increase in pulse and respiration rate is not due to the merely mechanical diminution of pressure, but to the deficiency of oxygen. Hence the physiological effects of high altitudes upon circulation and respiration are not purely physical, due to diminished pressure, but vital, and depend upon the change in the chemical composition of the atmosphere. The simple dimhmtion of oxygen without reduction of pressure will produce similar though not identical effects upon the organism. Above the height of 4000 metres above sea-level (below 460 millimetres pressure) the profounder disturbances of func- tion characterized as " mountain sickness " come on. Different 1 Results of a Scientific Mission to India and High Asia. By Hermann, Adolpbe, and Robert De Schlagintweit, vol. ii, pp. 484, 485. INFLUENCE OF CHANGES OF ATMOSPHERIC PRESSURE. 11 individuals react in different degree to the morbific influences of greatly diminished atmospheric pressure (and coincident reduc- tion of oxygen). Thus Glaisher reached an elevation of 11,000 metres (191.1 millimetres pressure) and returned to the earth alive, while Croce-Spinelli and Sivel perished at the considerably lower elevation of 8000 metres, equivalent to a pressure of 260 millimetres (7.2 per cent, of oxygen). The sanitarian is most concerned about the effects of press- ure of the atmosphere from 760 millimetres down to 460 milli- metres (or up to an altitude of 4000 metres above sea-level). The climatotherapy of various diseases requires that the effects of variations of pressure between these limits should be carefully studied. The observations of Mermod and Jourdanet 1 have illustrated the common physiological effects of these circum- scribed changes, while the experiences of therapeutists have established the fact very clearly that many cases of phthisis improve markedly in a rarefied atmosphere. Other observers have also shown that the effects of diminished pressure are not always beneficial, and Dr. Loomis has warned against the send- ing of patients with heart disease to high altitudes. Whether the lethal effects that have been recorded in such cases are due to the increased activity of the heart and heightened blood- pressure from deficient oxygen, or as suggested by Dr. F. Don- aldson, Jr., to dilatation of the heart- Avails from diminution of external pressure, is as yet unsettled. 2 It is probable that the diurnal or accidental 3 oscillations of barometric pressure at sea-level have no appreciable influence upon the organism. The statement is occasionally met that patients subjected to grave surgical operations oftener do badly during low atmospheric pressure, and some surgeons never 1 Jonrdanet states that while the French and Belgian soldiers in Mexico had an accel- erated pulse, the natives had a normal pulse. In Mermod's observations the average frequency of the pulse at St. Croix (1106 metres above sea-level) was nearly four beats greater than at Strass- burgh (142 metres). The condition of the natives at the high settlements of the Andes and Hima- layas has not yet been investigated with exactitude. * American Climatologkvil Association, Ib87. 3 Meaning the oscillation produced by storm waves. 12 TEXT-BOOK OF HYGIENE. operate when the barometer is low or falling if they can avoid it. An inquiry undertaken by the writer in 1876, in which the excellent records of the Massachusetts General Hospital and the observations of the Boston station of the United States Signal Service for five years were used as the basis of comparison, resulted negatively. The deaths following operations done on days when the barometer was high or rising were exactly equal in number to those following operations when the barometer was low or falling. Unfortunately, the investigation was never pursued to the extent of including other meteorological elements, such as humidity, cloudiness, precipitation, etc. The numerous studies of the relations of variations of pressure to the progress of infectious diseases have also failed to yield any fruits of value. Whether the nerve-pains so frequently complained of, especially by elderly patients, during the progress of areas of low barometer, are due to the diminished pressure, or to the influence of some other meteorological factor, such as humidity or electrical con- dition, cannot yet be decided. Increased atmospheric pressure, as noticed in caissons, tun- nels, and mines, produces increase in frequency and depth of respiration, diminution in the number of beats and volume of the pulse, pallor of the skin, increase of perspiration (although Smith states that this is only apparent and due to lack of evapo- ration from the surface), increased appetite, and more abundant excretion from the kidneys. Among the distinctly pathological effects of increased at- mospheric pressure are rupture of the drum of the ear, pain in the frontal and maxillary sinuses, neuralgic pains, nausea, some- times vomiting and local paralyses. Dr. A. H. Smith 1 defines this collection of symptoms as " The Caisson Disease," and gives the following summary of its characteristic features : " A disease depending upon increased atmospheric pressure, but always developed after the pressure is removed. It is char- 1 The Physiological, Pathological, and Therapeutical Effects of Compressed Air. p 47. Detroit, 1886. INFLUENCE OP CHANGES OF ATMOSPHERIC PRESSURE. 13 acterized by extreme pain in one or more of the extremities, and sometimes in the trunk, and which may or may not be associated with epigastric pain and vomiting. In some cases the pain is accompanied by paralysis more or less complete, which may be general or local, but is most frequently confined to the lower half of the body. Cerebral symptoms, such as headache and vertigo, are sometimes present. The above symptoms are con- nected, at least in the fatal cases, with congestion of the brain and spinal cord, often resulting in serous or sanguineous effu- sion, and with congestion of most of the abdominal viscera." INFLUENCE OF CHANGES OF TEMPERATURE ON HEALTH. Many of the derangements of health ascribed to high tem- perature are to a considerable degree due to other factors, promi- nent among which are high humidity, intemperance, overwork, and overcrowding. There can be little doubt, however, that the importance of the high temperature itself can hardly be over- rated. It has been generally accepted heretofore that a high temperature, together with a high relative humidity, is most likely to be followed by sun-stroke. A careful comparison in a series of deaths from sun-stroke in the city of Cincinnati in the summer of 1881 shows, however, conclusively that a very high mean temperature with a low relative humidity is more liable to be followed by sun-stroke than the high temperature when ac- companied by a high humidity. The same series of observa- tions also shows that the number of deaths was greater on clear days than on cloudy or partly cloudy days. 1 A corroboration of this result is found in the fact that sun-strokes very rarely occur on shipboard, at sea, where the relative humidity is always high. The direct influence of the sun's rays upon the skin pro- duces at times an erythcmatous affection which may run into a 1 The Run-stroke Epidemic of Cincinnati, O., during the Summer of 1881. A. J. Miles, Public Health, vol. vii, pp. 293-304. 14 TEXT-BOOK OF HYGIENE. dermatitis if the insolation is prolonged. Artificial heat may produce similar effects. Diarrhceal diseases, both of adults and children, are much more frequent during hot than cold weather (and in hot than in cold climates), but it is probable that other factors aid in the production of these diseases besides the high temperature. Certain epidemic diseases are likewise more frequent in, or exclusively confined to, hot climates. These are cholera, yellow fever, and epidemic dysentery. Elephantiasis, malarial fevers, and certain skin diseases seem also to have some connection with a constantly high external temperature. The intimate relation between cause and effect is not clearly understood, although the belief is current that the origin and spread of such diseases depend upon the development of various parasitic organisms. Regarding the morbific effects of continued high tempera- tures, it is probable that an appropriate mode of life, proper diet, and suitable clothing would avert many of the bad conse- quences. Nevertheless, the fact remains that certain tropical or hot-weather diseases must be considered as primarily dependent upon high temperature, although the pathological effects may be due to an intermediate factor. It is not improbable that micro- organisms will be found to explain yellow fever, cholera infan- tum, malarial fever, and tropical dysentery. Cholera has already been shown to depend upon a pathogenic organism. In this case the high temperature is one of the associate, but none the less indispensable, factors in the production of the disease. Extreme low temperature, as observed in the arctic regions, seems to produce a progressive deterioration of the blood (anaemia), in consequence of which most natives of temperate regions who are compelled to remain in the far north longer than two winters succumb to various luemic diseases, scurvy br- ing the most prominent. It is not improbable, however, that the dietary furnished is responsible for a large share of the evil effects ascribed to cold. The absence of sunlight for a consider- able part of the winter season may also have much to do with INFLUENCE OF CHANGES OF TEMPERATURE ON HEALTH. 15 the bad influences for which the low temperature is held responsible. Among the acute effects of great cold, frost-bite is the most frequent as well as the most serious. Loss of portions of the nose, or ears, or even of entire members are not infrequent results of frost-bite. In the arctic regions one of the most annoying affections which the traveler has to contend against is snow-blindness, a severe ophthalmia produced by the glare of the snow. Neutral tinted glass goggles should be worn as a preventive. 1 Ur. Henry B. Baker 2 has placed upon record a large mass of observations which appear to indicate that most of the acute diseases of the respiratory organs are caused by a low tempera- ture in conjunction with a low absolute humidity. Dr. Baker furnishes numerous diagrams, which seem to demonstrate that the curves for influenza, tonsillitis, croup, bronchitis, and pneu- monia are in general outlines all practically the same, and that they follow the curve for atmospheric temperature with surpris- ing closeness, rising after the temperature falls and falling after the temperature rises. He claims that this sameness indicates that the controlling cause is one and the same for all of these diseases, and that, directly or indirectly, the atmospheric tem- perature is that cause. They are diseases of the air-passages, and may be supposed to be influenced or controlled by the at- mosphere which passes through them. Although the curves are all similar, yet their differences still further support his view, because the order of succession of the several diseases is such as would be expected if caused in the manner which he sup- poses. Thus croup and influenza precede in time bronchitis and pneumonia ; the curve for bronchitis shows that disease to respond quicker than does pneumonia to the rise and fall of the 1 See Payer's Narrative of the Austrian Arctic Voyage of 1872-74, pp. 250-3 and 317, for an account of the effects of cold on the organism, and on the best prophylactic measures to be adopted. The Report of the Surgeon-General of the U. S. Navy for 1880 also contains (pp. 350-8) a valuable memorandum by Ex-Surgeon-General Philip S. Wales, on Arctic Hygiene. 8 Trans. Ninth International Med. Congress, vol. v. 16 TEXT-BOOK OF HYGIENE. temperature. He suggests that the explanation of the causa- tion of these diseases has not been grasped before because one of the principal facts has not been apprehended, namely, the fact that cold air is always dry air ; on the contrary, it has been generally stated that when these diseases occur the air is cold and damp. He explains that while the cold air is damp rela- tively it is always dry absolutely, and he thinks that its bad effects on the air-passages are mainly through its drying effects, which can best be appreciated by reflecting that each cubic foot of air inhaled at the temperature of zero, F. [ 17.8 C.], can contain only J grain of vapor [1.33 grammes per cubic metre], while when exhaled it is nearly saturated at a temperature of about 98 F. [36.5 C.], and therefore contains about 18J grains of vapor [about 43 grammes per cubic metre], about 18 grains of which have been abstracted from the air-passages. Thus cold air falling upon susceptible surfaces tends to produce an abnormal dryness which may be followed by irritation and suppuration. He claims that coryza is sometimes so caused. Under some conditions the nasal surfaces are not susceptible to drying, the fluids being supplied in increased quantity to meet the increased demand made by the inhalation of cold air. In that' case an unusual evaporation of the fluid leaves behind an unusual quantity of non-volatile salts of the blood, such as sodium chloride, and an unusual irritation results ; he thinks influenza is the name commonly given to this condition. The effects which the inhalation of cold air has on the bronchial surfaces depend greatly upon how the upper air-passages have responded to the increased demand for fluids ; because, if they do not supply the moisture it must be supplied by the bronchial surfaces, in which case bronchitis results. Finally, if the de- mands for moisture made by cold air are not met until the air- cells are reached pneumonia is produced. These claims are partly supported and partly opposed by an elaborate paper by Dr. J. W. Moore. 1 According to the 1 The Seasonal Prevalence of Pneumonic Fever, Trans. Ninth Internat. Congress, vol. v. INFLUENCE OF CHANGES OF TEMPERATURE ON HEALTH. 17 statistics furnished by this writer, bronchitis and pneumonia show a remarkable contrast as to seasonal prevalence. The sta- tistics of London and Dublin agree very closely upon this point. Bronchitis falls to a very low ebb in the third or summer quarter of the year (July to September, inclusive), when only 12 per cent, of the deaths annually caused by this disease take place in Dublin and only 11 per cent, in London. In the last or fourth quarter (October to December, inclusive) the percentage of deaths from bronchitis rises to 27 in Dublin and 30 in London. The maximal mortality occurs in the first quarter (January to March, inclusive), when it is 38 per cent, in both London and Dublin. In the second or spring quarter (April to June, inclu- sive) the bronchitic deaths decline to 23 per cent, hi Dublin and 21 per cent, in London. The mortality from pneumonic fever is differently distrib- uted throughout the year. In the summer quarter more than 14 per cent, of the annual deaths referable to the disease are recorded in Dublin and more than 15 per cent, in London. In the first quarter the figures are London, 31 per cent.; Dublin, 31 per cent. In the second quarter they are London, 26 per cent. ; Dublin, 30 per cent. In the fourth quarter they are London, 27 per cent. ; Dublin, 24 per cent. It therefore appears that the prevalence and fatality of pneu- monic fever from season to season do not correspond with the seasonal prevalence and fatality of bronchitis. The latter dis- ease increases and kills in direct relation to the setting in of cold weather ; it subsides in prevalence and fatality with the advance of spring and the advent of summer. Pneumonic fever, on the other hand, increases less quickly in winter and remains more prevalent in spring than bronchitis ; its maximal incidence coin- cides with the dry, harsh winds and hot sunshine of spring, when the diurnal range of temperature also is extreme. Dr. Moore believes that acute bronchitis is produced directly by the influence of low temperature, while pneumonia requires an additional cause, which he supposes to be a specific micro- organism. 2 18 TEXT-BOOK OF HYGIENE. HUMIDITY OF THE ATMOSPHERE AS CONNECTED WITH CHANGES IN HEALTH. The propagation of certain acute infectious diseases is be- lieved to be due to a high relative humidity. There can be no longer any doubt that a very humid soil and air, especially if connected with a variable temperature, are almost constant factors in the production of pulmonary phthisis. Recent experi- ence in this country and abroad has shown that the high plateaus and mountains, far inland, where the soil is dry and the relative humidity of the air low, are the best resorts for consumptives. Of the effects of excessively dry air on health little definite is known. It seems probable, however, that catarrhal affections of the respiratory mucous membrane are more frequent in a dry than in a humid climate. 1 THE SANITARY RELATIONS OF AIR-CURRENTS. Primarily, winds or air-currents may be considered as favor- able to health. By the agitation of the air ventilation is secured, foul air removed from insanitary places, and diluted by ad- mixture of purer air. But air-currents may also be regarded as either directly or indirectly unfavorably influencing health. Vertical currents rising from the ground may carry morbific germs or viruses and give rise to disease. Horizontal currents or winds proper may also be the direct or indirect cause of de- rangements of health. Full credit is given by the public to cold winds and draughts in producing catarrhs and rheumatic pains. The progression of certain infectious diseases, especially malaria, is believed with good reason to stand in a definite relation with the direction of the wind. Certain local winds are known to have a deleterious effect upon living beings, especially when the latter are in bad health. Among these winds is the mistral, a cold, dry, parching north- 1 See ante. SANITARY RELATIONS OF AIR-CURRENTS. 19 west wind which blows along the Gulf of Lyons. It brings on rheumatism and muscular pains, and is said to excite pleurisy and pneumonia and to act unfavorably upon consumptives. The bora is a colol, dry wind coming down from the Alps and continuing across the Adriatic. The Texan northers are well known in the southwestern part of the United States. They are extremely dry, and are often accompanied by a sudden fall of temperature. Changes of 28 C. (50 F.) within twelve hours are not infrequent in Western and Central Texas. Both man and beast suffer in- tensely from the cold, parching character of the wind. The sirocco of Northern Africa, Sicily, and Southern Italy has a wo rid- wide notoriety for its depressing effect upon human energy. The Jiarmattan is equally noted on the west coast of Africa. It is hot and dry, while in Southern Europe the sirocco is hot and moist. The simoon is a hot, scorching wind of India, and is said to be deadly in its effects upon vegetation and extremely dele- terious to men and animals who are encountered by it. In Australia and South Africa hot winds are said to occur which completely destroy vegetable life in their track, and are often unwholesome in their effects upon animal life. The evil reputation of the Alpine fohn is very well known, and neither native nor traveler is anxious to encounter it. It is warm and dry. With reference to the influence of electrical conditions of the atmosphere upon health, no observations have been made which justify definite conclusions. 1 Mr. Alexander Buchan and Dr. Arthur Mitchell have analyzed the influence of the weather and season upon the 1 Dr. S. Weir Mitchell has shown, from the record of the case of Captain Catlin, U. S. A. (American Journal Med. Sci., April, 1877, and N. Y.Med. Jour., August 25 and September 1, 1883), that attacks of neuralgia in this case, at all events accompanied the progress of storms across the continent. Also, that the periods of maximum pain occurred with a high but falling barom- eter and increasing absolute humidity. There seems also to be some relation in this case between the maximum pain and the maximum magnetic force as shown by the declinometer. Dr. Mitchell's papers are among the most valuable positive contributions to hygienic meteorology, and deserve careful study. 20 TEXT-BOOK OF HYGIENE. causation of disease, or, rather, upon the mortality from various diseases. 1 Taking the records of the city of New York from 1871 to 1877, it appears that the maximum number of deaths from small-pox occurred in May, the minimum in September. From measles there were two annual maxima and minima, the greater in July and September and the smaller in February and April. From scarlet fever the maximum was in April, the mini- mum in September. From typhoid fever the maximum was from August to November, the minimum almost equally distrib- uted throughout the rest of the year ; from diarrhoea, the maxi- mum in July and August, the minimum from December to March ; from diphtheria, the maximum in December, the mini- mum in August ; 2 from whooping-cough, maximum in Septem- ber and February, minimum in November and June ; for croup the curves agree pretty closely with the diphtheria curves ; from phthisis, the maximum in March, minimum in June. The following charts, reproduced by permission of the Massachusetts State Board of Health from the report of that body for 1888, show an almost identical movement of the mortality from different diseases throughout the year. They exhibit the reported mortality for 1888 and also for the six years from 1883 to 1888. From suicide, curiously, the greater number of deaths occurs in May, the smallest in February. This is contrary to the usual supposition that gloomy weather predisposes to suicide. The six summer months from April to September show a much larger number of self-murders than the remaining half-year. In eleven years, ending 1880, there were 1521 cases of self-destruction in New York. Of these 341 occurred during January, February, and March; 417 during April, May, and June; 412 during July, August, and September; and 351 during the last three months of the year. In Philadelphia, the results of examination 1 Journal Scottish Meteorological Society, 1875-78. (Abstract in Richardson's Prevent- ive Medicine, p. 533 et seq. Philadelphia, 1884.) a See paper on the Relation of Weather to Mortality from Diphtheria in Baltimore, by Richard Henry Thomas, in Trans. Med. and Chir. Faculty of Maryland, 1883. INFLUENCE OF SEASON UPON MORTALITY. 21 o> ~n oo m o> Q3 g 2 < > m PO w S I * *s " 2 3 <- <~ s ,- *zr K s r K O S X ^ 5 n ? s ^ o< o m s D ; R b ^ m e o in Liiini P r i o o z c^ G H O z 22 TEXT-BOOK OF HYGIENE. < INFLUENCE OF SEASON UPON MORTALITY. 23 ems TEXT-BOOK OF HYGIENE. INFLUENCE OF SEASON UPON MORTALITY. 25 I Ill il Hill ^L I DC DC ru z o O 26 TEXT-BOOK OF HYGIENE. of the statistics of suicide for ten years are almost exactly similar. Out of 636 cases of suicide, 78 occurred in May, 71 in August, 57 in December, 54 each in October, July, and April, 52 in June, 49 in November, 44 each in December and Feb- ruary, 43 in March, and 36 in January. 1 Dr. Lee is led to be- lieve that " a low barometric pressure, accompanied by a high thermometric registry, with sudden fluctuations from a low to a high temperature, together with much moisture and prevailing southwest winds, might somewhat account for the frequency of self-murder in the spring and summer months." THE SANITARY RELATIONS OF CHANGES IN COMPOSITION AND OF IMPURITIES IN THE AIR. The average proportion 9f carbon dioxide in the atmosphere is from 3 to 4 parts in 10,000. Pettenkofer 2 places the maxi- mum limit of carbon dioxide allowable in the air of dwellings at 7 parts in 10,000. It is probable that this limit is very fre- quently exceeded without serious consequences to health, if the air is not at the same time polluted by organic impurities, the products of respiration. Prof. William Ripley Nichols found the air in a school-room in Boston to contain eight times the normal proportion of carbon dioxide, while Pettenkofer found, also in a school-room, after the same had been occupied two hours, eighteen times the normal proportion, or 72 parts in 10,()00. 3 While such an excess of this poisonous gas must unquestionably have an unfavorable influence upon health, it is probable that the most serious effects are due to the coincident diminution of oxygen and the pollution of the air by the prod- ucts of respiration which necessarily take place during respira- tion. Carbon dioxide alone may be present in the air to a much greater extent than above mentioned without causing any appre- ciable inconvenience. In the air of soda-water manufactories 1 Suicide in the City and County of Philadelphia during a Decade, 1872 to 1881, inclusive, by John G. Lee, Trans. Am. Med. Asso., vol. xxxiii, p. 425. 8 Quoted in Buck's Hygiene and Public Health, vol. i, p. 615. 3 See table in Buck's Hygiene and Public Health, vol. i, p. 612. SANITARY RELATIONS OF IMPURITIES IN THE AIR. 27 there is frequently as large a proportion as 2 per cent, of this gas present without producing any ill effects upon those breathing such an atmosphere. The amount of carbon dioxide in the atmosphere is greatest at night. It is also greater very near the ground than at a dis- tance of several feet above it. As carbon dioxide is absorbed by the leaves of plants during the day-time, but given off at night, the difference may partly be thus accounted for. Accord- ing to Fodor, 1 the source of a large proportion of the carbon dioxide in the air is the decomposition going on in the soil. This accounts for the larger percentage of carbon dioxide near the ground. This would also explain the variation of the pro- portion of carbon dioxide in the air under different meteoro- logical conditions. For example, it is found that during rainy weather the carbon dioxide in the air is diminished. This is accounted for partly by the absorption of the carbon dioxide by the saturated ground, while at the same time the porosity of the soil is diminished and the escape of the ground-air prevented. Mr. R. Angus Smith made a number of 'experiments upon himself to determine the effects of an atmosphere gradually becoming charged with the products of respiration and per- spiration. His experiments were conducted in a leaden cham- ber holding 5 cubic metres of air. This air was not changed during the experiment. After remaining for an hour in this chamber, an unpleasant odor of organic matter was perceptible on moving about. The air, when agitated, felt soft, owing, doubtless, to the excess of moisture contained in it. The air soon became very foul, and, although not producing any dis- comfort, the experimenter states that escape from it produced a feeling of extreme pleasure, like " that which one has when walking home on a fine evening after leaving a room which has been crowded." 1 Hygienische Untersuchungen ueber Luft, Boden and Wasser, Braunschweig. 1882, 2te Abth. Air and Rain, p. 138. 28 TEXT-BOOK OF HYGIENE. Hammond l confined a mouse in a large jar in which were suspended several large sponges saturated with baryta water, to remove the carbon dioxide as rapidly as formed. Fresh air was supplied as fast as required. The aqueous vapor exhaled was absorbed by calcium chloride. The mouse died in forty-five minutes, evidently from the effect of the organic matter in the air of the jar. The presence of this organic matter was demon- strated by passing the air through a solution of potassium per- manganate. The horrible story of the " black hole " of Calcutta is familiar to every one. Of 146 prisoners confined in a dark cell at night, 23 were found alive in the morning. Among the sur- vivors a fatal form of typhus fever broke out, which carried off nearly all of them. After the battle of Austeiiitz 300 prisoners were crowded in a prison ; 260 died in a short time from inhal- ing the poisoned air. Numerous other similar examples of the effects of polluted air are recorded. Usually the effects of foul air are not so sudden and strik- ing. In most instances, especially where the pollution has not reached a high degree, there simply results a general deficiency of nutrition, which manifests itself in anaemia, loss of vigor of body and mind, and a gradual diminution of resistance to disease. It seems to be beyond question that persons who are con- stantly compelled to inhale impure air, especially if combined with an improper position of the body or lack of sufficient or appropriate food, furnish a very large percentage of chronic pul- monary affections. Phthisical patients, in the overwhelming majority of cases, are drawn from the classes whose occupations keep them confined in close rooms. Want of exercise and of good food doubtless aid in the development of the lung disease. Formerly, when less attention was paid to the proper construc- tion and ventilation of barracks and prisons, the mortality from 1 A Treatise on Hygiene, with Special Reference to the Military Service, by William A. Hammond, M.D., Surgeon-General U. S. Army, p. 170. Philadelphia, 1863. SANITARY RELATIONS OF IMPURITIES IN THE AIR. 29 phthisis among soldiers and criminals was much greater than it is now. In animals kept closely confined the same disease claims a large share in the mortality. Near the end of the last century over one-third of the in- fants born in the old Dublin Lying-in Hospital died of epidemic diseases. After the adoption of an improved system of ventila- tion the mortality fell to about one-tenth of what it had pre- viously been. To illustrate the effect of similar conditions upon the health of domestic animals, the following instance is cited : Upward of thirty years ago a severe epidemic of influenza in horses appeared in Boston. At the instigation of Dr. H. I. Bowditch, every stable in the city was inspected, and classified as " excellent," " imperfect," or " wholly unfit," in respect to warmth, dryness, light, ventilation, and cleanliness. It was found that in the first class fewer horses were attacked and the disease was milder, while in the third class every horse was attacked and the more severe and fatal cases occurred. Carbon monoxide is a very dangerous impurity often present in the air of living-rooms. Being an ingredient of illuminating gas, as well as the so-called coal-gas, which so frequently escapes from stoves and furnaces, its dangerous char- acter becomes apparent. Many persons die every year in this country from the inhalation of illuminating gas. People un- acquainted with the mechanism of the gas-fixtures frequently blow out the light instead of cutting off the supply of gas by turning the stop-cock. It is also a prevailing custom to keep the light burning " low " during the night. Any considerable variation of pressure in the pipes, or sudden draught, may put out the light and permit the gas to escape into the room, with fatal effect. Leaks in pipes or fixtures may have the same results. Coal-, coke-, or charcoal- fires may produce serious or fatal poisoning if the gas, which contains a large proportion of car- bon monoxide, is permitted to escape into the room. 1 In > See paper by Dr. John Graham in Transactions of Philadelphia College of Physician* for 1885. 30 TEXT-BOOK OF HYGIENE. certain parts of Europe, notably in France, the inhalation of the fumes of a charcoal fire is a favorite method of committing suicide. The gas which sometimes escapes from the stove when coal is burning has the following composition : Carbon dioxide, 6.75 per cent. Carbon monoxide, 1.34 " Oxygen, 13.19 " Nitrogen, 79.72 " Sulphuretted and carburetted hydrogen are not infrequently present in the air, especially about cess-pools and in mines and certain manufacturing establishments. Sulphuretted hydrogen is generally considered to be a violent poison, but there is no evidence that it is so unless oxygen is excluded. Carburetted hydrogen is the so-called "fire-damp" of mines, which is so often the cause of fatal explosions. Its in- halation does not seem to be especially noxious. It will be more fully referred to in a succeeding chapter. Variations in the proportion of ammonia present in the air are frequent. Its presence is an indication of organic decom- position in the vicinity, but nothing is known of the influence of the gas itself upon health, in the proportion in which it is ever found in the atmosphere. SEWER-AIR. Sewer-air, or sewer-gas, as it is often improperly called, is a variable mixture of a number of gases, vapors, atmospheric air, and solid particles, and is derived from the decomposition of the animal and vegetable contents of sewers. A number of analyses by different chemists have shown that the composition of sewer-air is extremely variable. The most important com- ponents, in addition to the constituents of atmospheric air, are : Carbon dioxide, ammonia, sulphuretted hydrogen, and a number of volatile organic compounds, which give to sewage its peculiar odor, but which are present in such small quantity as to prevent SfcWER-AIR. 31 accurate determination by chemical means. Sewer-air may also contain particulate bodies, bacteria, and other microscopic or- ganisms, which are supposed by many to be the active causes of infectious diseases. Some recent researches by Carnelly and Haldane have shown that sewer-air usually contains a less number of micro-organisms than the external air of cities. The proportion of carbon dioxide found was also much less than was expected. When the contents of sewers remain in these re- ceptacles or conduits long enough to undergo decomposition, sewer-air is always present. It is believed by some physicians and sanitarians that sewer-air is the direct cause of such diseases as typhoid fever, scarlet fever, diphtheria, and cholera, while others hold the view that the sewer-air is merely a favorable breeding-place for the germs of these diseases, and that it thus merely acts as a medium in which the infective agent grows, re- produces itself, and is conveyed from place to place. There is no absolutely trustworthy evidence in favor of either of these doctrines. It is hardly open to question, however, that the continual breathing of air polluted by emanations from sewers often pro- duces more or less serious derangements of health. Diarrhoea and other intestinal affections, mild cases of continued fever, and even cases of undoubted typhoid fever have been so frequently noted in connection with defective sewerage, and the escape of sewer-air into inhabited rooms, that doubt upon this point is hardly justifiable. With regard to typhoid fever, however, it is probable that the sewage in these cases contained the particular virus (bacillus ?) which, it is now generally believed, causes this disease. The effluvia from cemeteries, knackeries, and other places where the bodies of animals are undergoing decomposition, are popularly regarded as deleterious in their effects upon health. The evidence in favor of this view is, however, very indefinite. Professor Tyndall has shown l that even the apparently 1 Essays on Floating Matter of the Air. New York, 1882. 32 TEXT-BOOK OF HYGIENE. clearest air is, when in motion, constantly filled with innumerable particles of dust, which are believed by many to give rise to various forms of disease. The presence of these particles can be easily demonstrated by means of the electric light. Every one has observed these minute particles in a bright ray of sun- light. Under ordinary conditions these particles of dust would, of course, give rise to no trouble, but, if intermingled with these dust-specks there were disease germs, whether these germs be considered as living organisms, or as particles of dead tissue from the body, then manifestly the inhalation of such "dust" would be dangerous. 1 The quantity of dust found in the air of cities is much greater than in the country. Tissandier found that in Paris the percentage of dust was eight to twelve times greater than in the open country. One-fourth to nearly one-half of this atmos- pheric dust is organic, either animal or vegetable. Very recent observations have shown that in Paris the air contains nine or ten times as many bacteria in a given volume as the air at the observatory of Montsouris, just without the city. The relative proportions of organic and inorganic particles vary as 25 to 75 in Paris, 45 to 55 in Dublin, and 25 to 75 in the open country. The organic particles are either particles of dead or- ganic matter, or minute organisms. The proportion of the latter varies in different seasons, being least in winter and spring, and greatest in summer and autumn. These organisms are not necessarily pathogenetic, but the conditions which favor the proliferation of non-pathogenic bacteria are likely to promote the development of disease-producing ones likewise. Among the pathogenic micro-organisms found in the at- mosphere are spores of achorion Schoenleinii, the so-called ma- laria bacillus of Klebs and Tommasi-Crudeli, and Fehleisen's erysipelas germ. It is probable, also, that the bacilli of tuber- culosis, cholera, and typhoid fever, and other organisms, at times 1 See Chapter IX, on Industrial Hygiene, for effects of inhalation of dust in various industries. SEWER-AIR. 33 undergo multiplication in the air, and that the latter may be the medium of communication of these diseases. But it must be admitted that our knowledge upon this point is at present rather vague and unsatisfactory. As regards the diseases that may be produced by the in- halation of pathogenic organisms there can be no doubt that diphtheria, glanders, measles, scarlet fever, whooping-cough, in- fectious pneumonia, and, above all, pulmonary tuberculosis, are so caused. It is likewise probable that yellow fever, epidemic influenza, cholera, and typhoid fever may be produced in this manner. TESTS FOR IMPURITIES IN THE AIR. The sense of smell will indicate the presence of sulphu- retted hydrogen, or of volatile organic matter. Chemical tests and the microscope will, however, be necessary to determine the presence of carbon dioxide, carbon monoxide, or suspended particulate matter in the air. In order to detect the presence of carbon dioxide, advantage is taken of the affinity of this compound for certain alkalies with which it forms insoluble compounds. If a stream of carbon dioxide gas is passed through lime- or baryta- water, an insoluble carbonate of lime or baryta is instantly formed, and produces a milky precipitate in the water. If, instead of passing a stream of gas through the liquid, the latter be agitated with air con- taining carbon dioxide, a similar precipitate is produced. The most exact method of determining the amount of carbon dioxide in the air is that known as Pettenkofer's, 1 but it is somewhat complicated. A readier method has been devised by Mr. Angus Smith, and is termed the minimetric test. 2 A series of six wide- mouthed bottles, having a capacity respectively of 450, 350, 300, 250, 200, and 150 cubic centimetres, 3 is fitted with clean, tightly- 1 Lehrbuch der Hygiene, Nowak, p. 149. Op. cit., p. 152. 3 The equivalents in English measures are 14 ounces. 11 ounces, 9^ ounces, 8 ounces, & ounces, and 4% ounces. 3 34 TEXT-BOOK OF HYGIENE. fitting corks. The bottles are made perfectly clean and dry, and 15 cubic centimetres (3 drachms) of clear, fresh lime- or baryta- water put into the smallest, the cork replaced, and the bottle well shaken. If the water becomes turbid there is at least .16 per cent. (16 parts per 10,000) of carbon dioxide in the air treated. If only the water in the largest bottle becomes cloudy, the proportion of carbon dioxide is probably less than 5 parts in 10,000. For the intermediate series of bottles the amounts of carbon dioxide necessary to produce cloudiness are, respectively: For 200 cubic centi- metres of air, 12 parts in 10,000; for 250 cubic centimetres, 10 parts; for 300 cubic centimetres, 8 parts; and for 350 cubic centimetres, 7 parts per 10,000. If, therefore, a cloudiness is produced with any of the bottles except the largest, the amount of carbon dioxide present exceeds the standard allowable in pure air. The test should be frequently made, in order to acquire familiarity with its use. The same quantity of the test-liquid is, of course, used in each bottle. A simple and easily-managed instrument, called an " air-tester," has been devised by Professor Wolpert, a distinguished German meteorologist. It is described as follows by Dr. S. W. Abbott, who first called attention to its merits in this country 1 : The little instrument consists of a simple rubber bulb (A) of a capacity of 28 cubic centimetres, a glass outlet-tube (B) with a constriction near its extremity (E). A glass test-tube, 12 centimetres in length (C) and 2 millimetres in diameter, has a horizontal mark near the bottom, indicating the point to which it must be filled with perfectly clear lime-water, to contain 3 cubic centimetres. The bottom of the tube is whitened and has a black mark stamped upon it (D). A small, wooden stand, a brush or swab, a vial of vinegar for cleaning the tube, and a bottle of clear lime-water complete the outfit. 1 Boston Mecl. and Surg. Journal. FIG. 2. AIR-TESTER. TESTS FOR IMPURITIES IN THE AIR. 35 In order to use the instrument, the lime-water (saturated solution) should be poured into the test-tube till it reaches the horizontal mark. Press down the bulb with the thumb, so as to expel the air within it as completely as possible, and allow it to fill with the air of the apartment, insert the small tube into the lime-water nearly to the bottom, and again expel the air with moderate rapidity, so that the bubbles may rise nearly to the top of the tube, but do not overflow, taking care to continue the pressure of the thumb till the small tube is removed from the lime-water. Repeat this process until the mark upon the bottom of the test-tube is obscured by the opacity produced by the reaction of the carbonic acid upon the lime-water, the observer looking downward through the lime-water from the top of the test-tube. With very foul air it is necessary to examine the mark after filling and discharging the bulb a few times only; with good air, it must be filled twenty-five times and upward. The bulb represented in the cut is made a little larger than the required capacity, since a small amount of residual air usually remains in the bulb and cannot be expelled without great care. After each observation, the test-tube must be washed out and wiped dry. If a white incrustation forms upon the tube, it may be easily removed with a little vinegar, after which the tube should be thoroughly washed with pure water and dried. If the mark becomes obscured after filling the bulb ten or fifteen times only, the air of an apartment is unfit for continuous respiration. In a sick-chamber the air should be so pure that the tur- bidity of the lime-water will not render the mark invisible until thirty or forty fillings are made. The instrument should be used by daylight, over a white ground, as a sheet of writing-paper, and care should be taken not to vitiate the result by the observer's own breath. The following approximate table is taken from the article 36 TEXT-BOOK OF HYGIENE. by Professor Wolpert, the first column representing the number of fillings of the bulb, and the second column the parts per 10,000 of carbon dioxide in a given sample of air: Number of Fillings. Carbon Dioxide per 10,000. Number of Fillings. Carbon Dioxide per 10,000. Number of Fillings. Carbon Dioxide per 10,000. 1 200. 21 9.5 41 4.9 2 100. 22 9.1 42 4.8 3 67. 23 8.7 43 4.6 4 50. 24 8.3 44 4.5 5 40. 25 8. 45 4.4 6 33. 26 7.7 46 4.3 7 29. 27 7.4 47 4.2 8 25. 28 7.1 48 4.1 9 22. 29 6.9 49 4.1 10 20. 30 6.6 50 4. 11 18. 31 6.4 51 3.9 12 16. 32 6.3 52 3.9 13 15. 33 6.1 53 3.8 14 14. 34 5.9 54 3.7 15 13. 35 5.7 55 3.7 16 12.5 36 5.5 56 3.6 17 12. 37 5.4 57 3.5 18 11. 38 5.3 58 3.5 19 10.5 39 5.1 59 3.4 20 70. 40 5. 60 3.3 Carbon monoxide is detected by its reaction with palladium chloride, which gives a black color when brought in contact with the gas. If a strip of linen or blotting-paper be moistened with a solution of the palladium chloride (1 to 500) and sus- pended in air containing carbon monoxide, the black color will be developed. The suspected air may also be passed through a solution of sodio-chloride of palladium, when the liquid will turn black if carbon monoxide be present. The percentage of organic impurity in the air of an occu- pied room (products of respiration, etc.) is difficult to ascertain directly. Pettenkofer has found, however, that the proportion of carbon dioxide present is indirectly a measure of the organic impurity from respiration. As the determination of the carbon TESTS FOR IMPURITIES IN THE AIR. 37 dioxide is easy by the minimetric method of Angus Smith, or the ready method of Wolpert, the extent to which the air is polluted by respiratory impurities is readily ascertained. 1 The presence of organic and other suspended impurities can be best demonstrated with a microscope. An objective, mag- nifying upward of 400 linear diameters, and experience in the use of the instrument will be needed to obtain correct results. By moistening a . glass slide with glycerin and exposing it in the suspected air, a sufficient quantity of the suspended matters may be collected in the course of twenty-four hours to permit some conclusions to be drawn from a microscopic examination. 2 A common method of determining the presence or absence of a large quantity of carbon dioxide, for example, at the bottom of a well or privy-vault is to lower a lighted candle to the bottom. If the light is extinguished, the air is considered irre- spirable ; but, if it continue burning brightly, the air is believed to be sufficiently pure to sustain life. Sulphuretted hydrogen and sulphide of ammonium are sometimes found in privy- vaults, and, although they will not extinguish a light, they speedily prove fatal if inhaled in a concentrated form, and to the exclu- sion of a sufficiency of oxygen. 3 Cases have frequently occurred where serious or fatal results ensued from the presence of a dan- gerous gas, which was thought to be excluded by the burning candle. 1 Recent observations in this country (see Annual Reports of the Surgeon-General of the Navy for 1879. pp. 45 and 46, and the same for 1880, pp. 31 to 34) seem to throw some doubt upon the entire reliability of this method of determining the amount of organic matter in the air examined. Trof. Ira Remsen (Report National Board of Health, 1879, p. 77, and 1880, p. 308 et seq.) has shown the insufficiency of the chemical methods at present in use, and points out the difficulties of making trustworthy and satisfactory determinations of organic matter in the air. The great technical difficulties of the various analytical processes render it unwise to burden these pages with a description of them. Only expert chemists are qualified to make a thorough air analysis, and the author does not feel competent to offer advice to them. Dr. Cornelius B. Pox's book on " Sanitary Examinations of Water, Air, and Food," and Fliigge's "Lehrbuch der Hygienischen Untersuchungsmethoden" contain detailed descriptions of the best methods employed. a Dr. G. M. Sternberg, U. 8. A. (Report National Board of Health, 1880), gives an ac count of his investigations into the suspended matters of the air. The question is also con- sidered in a practical manner by Surgeons Kidder and Streets, TJ. S. N., in Reports of the Surgeon-General of the Navy for 1880 and 1881. See also Bacteria, Sternberg and Magnin, 2d ed., p. 197. See a case reported in Philadelphia Medical Times, October 21, 1882. 38 TEXT-BOOK OF HYGIENE. It is advisable in all cases to exhaust the stagnant air in old wells and privy-vaults before permitting any one to descend. Perhaps the feadiest method of exhausting the vitiated air in such places would be to lower heated stones, masses of hot iron or pails of hot water, to near the bottom, which produce a rare- faction of the air and cause it to ascend. Its place will then be occupied by purer air from without. The rarefaction produced by the explosion of gun-powder has also been made use of with success ; but this has some objections, because the combustion of powder itself produces gases which are noxious if breathed in large quantity. An animal, such as a cat or dog, should be first lowered into the suspected well for fifteen or twenty min- utes, in order to determine whether the air at the bottom is capable of sustaining life, before permitting the workmen to descend. Similar precautions should be used in old, long- unused mines to prevent fatal effects from the so-called " choke- damp," which is largely composed of carbon dioxide. PRINCIPLES OF VENTILATION. During ordinary respiration an adult human being adds 900 grammes = 455,500 cubic centimetres (14 cubic feet) of carbon dioxide to, and abstracts 744 grammes = 516,500 cubic centimetres (16 cubic feet) of oxygen from, the atmosphere in twenty-four hours. Hence, if the individual were confined in an apartment where the inclosed air could not be intermingled by diffusion with the atmosphere without, the proportion of carbon dioxide would soon become so great that the processes of life could not be sustained, and the individual would die. This result would be reached even sooner than the point here mentioned, for the organic matter exhaled from the lungs and the surface of the body would increase the poisonous condition of the air even more than the carbon dioxide given off. It is easily seen, therefore, how important the study of the principles and practice of ventilation becomes in hygiene. In this chapter only the principles underlying this subject can be definitely PRINCIPLES OF VENTILATION. 39 stated. Practical details will be more fully given in the chapters devoted to dwellings, schools, hospitals, etc. It is generally accepted among sanitarians that the presence of .07 per cent. (7 parts in 10,000) of carbon dioxide in the air indicates the greatest amount of organic impurity (from respira- tion or combustion) consistent with the preservation of health. As each individual gives off from his lungs, in the process of respiration, 316 cubic centimetres of carbon dioxide per minute, the diffusion in the air surrounding him must be sufficiently rapid to keep the air to be breathed at the standard of .07 per cent, above mentioned. Adopting this as the standard of maximum impurity allow- able, 90 cubic metres of fresh air per hour will be needed for each individual to keep him supplied with pure air. This is for a person in a state of health ; in cases of disease a more rapid change of air will be necessary to keep that surrounding the patient in a state of purity. Ventilation is defined by Worcester as " the replacement of noxious or impure air in an apartment, mine, or inclosed space by pure, fresh air from without." By Dr. Parkes the term is restricted to " the removal or dilution, by a supply of pure air, of the pulmonary and cutaneous exhalations of men and the products of combustion of lights in ordinary dwellings, to which must be added, in hospitals, the additional effluvia which proceed from the persons and discharges of the sick. All other causes of impurity of air ought to be excluded by cleanli- ness, proper removal of solid and liquid excreta, and attention to the conditions surrounding dwellings." A proper system of ventilation must take into consideration the cubic space of the apartment or building to be ventilated, the number of persons ordinarily inhabiting this space, whether constantly or only temporarily occupied, and certain other col- lateral elements, such as the character of the building to be ventilated, its exposure, necessity for artificial heating, etc. 1 Manual of Practical Hygiene, 6th ed., New York, vol. i, p. 157. 40 TEXT-BOOK OF HYGIENE. The amount of cubic space that must be allowed to each individual is determined by the rapidity with which fresh air must be supplied in order to keep that surrounding the indi- vidual at the standard of less than .07 per cent, of carbon dioxide. For example, in a space of 3 cubic metres, the air must be changed thirty times in an hour, in order to prevent the carbon dioxide exceeding the above proportion ; that is to say, to allow 90 cubic metres of air to pass through that space in the time mentioned. This would create an uncomfortable, if not injurious, draught. If the space contained 30 cubic metres, the air would need renewal only three times an hour. A space of 15 cubic metres could be kept supplied with pure air without perceptible movement if all the mechanical arrangements for changing the air were perfect ; but such per- fection is rarely attainable, and hence there would be either draughts or insufficient ventilation in such a small " initial air- space," as it is termed. The initial air-space should, therefore, be not less than 30, or, better, 40 cubic metres. The air of this space could be changed sufficiently often to keep it at its standard of purity without creating unnecessary draught. For sick per- sons this should be doubled. In hospitals, therefore, the cubic air-space allowed to each bed should not be less than 60 to 80 cubic metres. As stated, the purposes for which the building or apartment to be ventilated are employed require differences in the cubic space and in the volume of fresh air supplied. Morin gives the following table : TABLE III. Fresh Air Required per Hour per Head. Hospital wards for ordinary cases, . 60-70 cubic metres. Hospital wards for surgical and obstet- rical cases, 100 " " Hospital wards for contagious diseases, 150 " " Prisons, 50 " " PRINCIPLES OF VENTILATION. 41 Workshops | ordinar y occupations, . 60 cubic metres. (unhealthy, "' . 100 " " Barracks, jduring the day, . . 30 ( " " night, . . 40-50 " " Theatres, 40-50 " " Assembly rooms for long receptions, . 60 " " " " " brief u . 30 " " Primary schools, 12-15 " " Higher " 25-30 " " Stables, 180-200 " " These figures are not excessive from a sanitary stand-point, although few buildings meet the requirements here set down. The source of the air supplied must, o*f course, be capable of yielding pure air. It should not be drawn from damp cellars or basements, or from the immediate vicinity of sewers or drains. Air taken from such places is little better for respiration than that which it replaces in the apartments to be ventilated. Ventilation may be accomplished either with or without artificial aids. In buildings or rooms, used as habitations, natural ventilation (with, perhaps, the simplest mechanical aids) is made use of almost entirely. In large buildings, such as churches, theatres, schools, or in ships and mines, one of the artificial systems must be adopted if efficient ventilation is desired. Natural ventilation takes place by diffusion, by perflation, and in consequence of inequality of atmospheric pressure. By diffusion is meant the slow and equable entrance of air from without and exit from within a room through the walls or ill- made joints without the influence of wind-currents. In an occupied room this is, however, insufficient to keep the air pure, because many of the organic impurities of respired air are mole- cular, and, therefore, incapable of making their way out of the rooms through the walls. Perflation means, literally, " blowing through," and, if the direction and force of air-currents could be regulated, this would, with simple mechanical arrangements, be an efficient means of 42 TEXT-BOOK OF HYGIENE. ventilation. However, the uncertainty of the force and direc- tion of the wind makes this method of ventilation untrustworthy, except in warm weather. Unequal pressure between the air in a room and that without is, within certain limits, an efficient means of ventila- tion, and is usually relied upon in ordinary apartments. When the air in a room is heated above the temperature of the external air, either by a fire, lights, or by the presence of a number of persons in the room, it expands, and part of it finds its way out through numerous crevices and bad joints found in all buildings. The air which remains, being less dense than the external air, the latter enters the room by various openings, until the equality of pressure is re-established. But as the heating of the enclosed air continues, the process is momentarily repeated and becomes continuous. Although the impurities of respired air (carbon dioxide, organic matter) are heavier than the air itself at the same temperature, it is a familiar fact that the most impure air in an occupied room is always found near the ceiling, the impurities being carried upward with the heated air, and that the pure air from without, being colder, fills the lower part of the room. If the cold, outside air were to be admitted at the bottom of the room, and means allowed for the escape of the hot air at the top, the conditions of the old health-maxim, to " keep the feet warm and the head cool," would be reversed, This would be no less uncomfortable than unwholesome. In all plans for natural ventilation, therefore, provision must be made to secure a gradual diffusion of the cold, outside air from above, or to have it warmed before it enters the room. With a large chimney as an aspirating shaft, 1 with flues at the top and bottom of the room, and openings in the walls of the room near the ceiling to admit fresh air, sufficient ventilation can be usually secured in cold weather, in a room not overcrowded. 1 Of course there is really no such thing as a real aspiration, or "sucking out" of the air through the chimney or so-called "aspirating shaft." The upward movement of the air in the shaft is due to its displacement by the colder or denser air entering the room. PRINCIPLES OF VENTILATION. 43 When a room is heated by a furnace, the fresh air is warmed before it is introduced, and the foul air escapes either through a ventilating shaft, a ventilator in the window or wall, or through the numerous fissures and other orifices which defective car- pentering always leaves for the benefit of the health of the occupants. The following rules for the arrangement of a system of natural ventilation are modified and condensed from Parkes 1 : The apertures of entrance and of exit for the air should be placed far enough apart to permit thorough diffusion of the fresh air. When the air is brought into a room through slits or tubes in the walls near the ceiling, the current should always be deflected upward by an inclined plane, in order to prevent a mass of cold air from descending over the shoulders of the occupants and chilling them. The air must be taken from a pure source. The inlet-tubes should be short, and so made as to be easily cleansed, otherwise dirt lodges and the air becomes impure. Inlets should be numerous and small, to allow a proper distribution of the entering air. Externally, the inlets should be partially protected from the wind to prevent strong draughts ; they should also be pro- vided with valves to regulate the supply of air. If the air cannot be warmed, the inlets must be near the ceiling ; if it can be heated, it may enter near the floor. The air may be warmed by passing it through boxes con- taining hot water or steam coils, by passing it through chambers around grates or stoves, or heating it in a furnace. In towns or manufacturing districts the air should be filtered before allowing it to enter the room. Thin flannel or muslin spread over the openings answers very well as filtering material. Outlets should be placed at the highest point of the room 1 Manual of Practical Hygiene, 6th ed., New York, vol. i, p. 177. 44 TEXT-BOOK OF HYGIENE. and should be protected from the weather. An opening into the chimney near the ceiling will answer well in many cases. In one-story buildings, ridge-ventilators make the best out- lets. The entrance of snow and rain must be prevented by suitable arrangements. A small space or slit between the horizontal bars of the upper and lower window-sash will admit sufficient air in a proper direction in small rooms, even when the window is shut. In all rooms, howsoever ventilated, doors and windows should be often opened to permit a thorough flushing of the interior with fresh air. For large buildings, hospitals, schools, theatres, ships, and mines two systems of artificial ventilation are in use. One operates by extracting the foul air by means of fans, the other by forcing in fresh air, allowing the impure air to find its way out as best it may. Rotating cowls on the tops of chimneys may be used to increase the aspirating power of the air ; in this way the natural force of the wind may be utilized for ventilation of rooms or buildings of moderate size. Further details upon the practical application of these prin- ciples will be given in succeeding chapters of this work. [In addition to the works mentioned in the text the follow- ing may be referred to as more fully treating of the subjects considered in this chapter : Flammarion : The Atmosphere. The Articles on Atmosphere and Climate in the Encyclopaedia Britannica, 9th edition. Reports of the Chief Signal Officer of the Army. A paper on Climate and Diseases, by Dr. Cleveland Abbe, in Report of National Board of Health for 1880. Die Canalgase, by Dr. F. Renk, Mnnchen, 1884. Morin : On Warming and Ventilating Occupied Buildings ; translated in Smithsonian Report for 1873 and 1874. Y. Pettenkofer und Ziemssen's Handbuch der Hy- giene, I Theil, 2 Abtheilung. Die Luft, by Dr. F. Renk. A. Woeikof:- Die Klimate der Erde, 1887. B. W. James: American Resorts, 1889. A. W. Greely : American Weather, 1888. Jules Rochard : Questions d'Hygiene Sociale ; L'Acelimatement dans les Colonies Fran9aises, 1891. Kenwood : The Hygienic Laboratory, Part III, 1893.] QUESTIONS TO CHAPTER I. AIR. What is the composition of the atmospheric air ? Is the mixture a chemical or mechanical one ? What constituent is the most constant in proportion, and what ones most variable? What are the causes and limits of variation in the composition of the air ? Has this variation any effect upon health ? How is the general uniformity of composition maintained? What is the relation of the oxygen and carbon dioxide to plant and animal life and to one another ? What is the depth of the atmosphere ? What is its weight, and how is this measured ? How may you determine the altitude of any place above the sea-level ? What effect has temperature on barometric pressure ? What effect has moisture, and why? Whence does the air derive its warmth? Where is the atmosphere warmest ? What is the relation between the temperature and humidity of the air ? What is meant by " absolute " and " relative " humidity ? How is each always designated ? What is meant by " saturation "? What causes motion in air or wind? What conditions of the atmos- phere probably have relation to, or influence upon, disease ? Why should a sanitarian be a practical meteorologist? What are the physiological effects of diminution of atmospheric pressure ? What may aggravate these effects ? To what are they due ? Can the human body become accustomed to them? What name is given to this pli3 T siological disturbance ? What diseases will probably improve in a rarefied atmosphere, and what ones will not ? What are the effects of increased atmospheric pressure upon the organism ? Is there any danger of fatal results ? Have the diurnal variations of pressure any effect upon the body in health or in disease? What effect has high temperature upon health ? What diseases are more frequent in hot weather and in hot climates ? What peculiar affection seems to be caused or favored by long- continued exposure to cold? What are some of the acute effects of (45) 46 QUESTIONS TO CHAPTER I. cold? What effect has the relative humidity in the production of these diseases? Indicate and explain a possible relationship of causation between coryza or influenza, bronchitis and pneumonia. Is this altogether substantiated by statistics ? Is low temperature the only cause of pneu- monia ? What part has the relative humidity in the production of certain diseases ? What is the general rule as to the effect of winds or air-currents upon health ? Name some apparent exceptions to this rule. Has the season an} r thing to do with the morbidity and mortality from different diseases ? Give examples. What is the average proportion of carbon dioxide in the atmos- phere ? What should be the maximum limit permissible in dwellings ? Is this limit often exceeded ? When exceeded, to what are the evil effects upon health probably due? How much carbon dioxide alone may be present in the atmosphere without producing any apparent ill effects ? When and where in the out-door atmosphere is the proportion of carbon dioxide greatest ? In what way may this be explained ? What are the products of respiration and perspiration, and which of these is most harmful to health ? What evidence have we to that effect? Have we any evidence that the respiratory carbon dioxide alone is harmful to health ? Where there is a moderate degree of re- spiratory pollution, what are some of the symptoms usually produced thereby ? In the production of what especial disease has impure air a decidedly causative influence? Which is the more dangerous to health, carbon monoxide or carbon dioxide? Of what gases is the former an ingredient? How does it produce its harmful effects? Have sulphuretted and carbnretted hydrogen any effect upon health? If so, in what proportions must they be in the atmosphere ? Has ammo- nia, in the proportion in which it is usually found in the atmosphere, any bad effect upon health ? What is sewer-air' or sewer-gas, and what are some of its constit- uents ? In what way may it be the cause of infectious disease ? Will the continued breathing of air polluted with sewer-gas affect health, and, if so, what symptoms may be caused thereby ? What must be necessarily present in the sewer-gas for it to be a cause of typhoid fever? Is there any positive evidence that the emanations from cemeteries, bone-yards, etc., are harmful to health ? QUESTIONS TO CHAPTER I. 47 What diseases may be produced by the inhalation of pathogenic micro-organisms carried by the air ? What tests have we for the various impurities in the air ? What reagents may be used to determine the presence and amount of carbon dioxide in the atmosphere ? Describe briefly the Angus Smith minimet- ric test and Wolpert's air-tester. What precautions must be observed with the latter? Wherein may each be improved? (See chapter oil " Examination of Air, Water, and Food," page 413.) What reagent is used to detect carbon monoxide ? Can the amount of respiratory organic matter in air be readily determined directly ? What discovery did Pettenkofer and de Chaumont make regarding the relation between the respiratory organic matter and carbon dioxide in the air? How may the presence of quantities of carbon dioxide sufficient to endanger life be determined in wells or cess-pools, and how may such quantities of this gas be removed ? What other gases dangerous to life might be present in cess-pools and yet not be indicated by the above test ? Ventilation. How much oxygen does an adult human being at rest ordinarity take from the air, and how much carbon dioxide does he add to it in twenty -four hours ? What percentage of carbon dioxide in the air indicates the greatest amount of organic impurity from respiration, etc., consistent with health? How much fresh air per hour is, therefore, needed by each individual to maintain this state of purity ? Will sick persons need more fresh air than the well ? Why ? What is meant by ventilation? What should be excluded from the term? What matters must a proper system of ventilation consider? What governs the amount of cubic space that can be allotted to each individual ? What should be the minimum air-space for the well, and what for the sick? What should be the floor-space for each person, and why ? From what kind of a source must the air for a ventilation supply be taken ? What is the difference between natural and artificial ventilation ? What are the forces acting to produce natural ventilation ? What is meant by diffusion ? Why is it insufficient for ventilating an occupied room? What is meant by perflation? Why cannot it be used alone for ventilation? Upon what does the inequality of atmospheric pressure depend ? Why is it the most valuable of the forces of natural ventilation ? In what part of an occupied room is the most impure air found, and why ? What precautions must be observed in all plans for natural ventila- 48 QUESTIONS TO CHAPTER I. tion ? What makes the air from a room pass up a chimney ? When a room is heated by a hot-air furnace, how does the foul or used air escape? What rules may be laid down for the arrangement of a system of natural ventilation ? Where should the fresh-air inlets of a room be located ? How may the air be warmed before bringing it into the room ? How should the inlet-tubes be arranged ? Where should the outlets of a room be located ? What systems of artificial ventilation may be employed for large buildings or rooms ? By what appliances may we make use of winds for ventilating purposes ? CHAPTER II. WATER. PHYSIOLOGISTS teach that nearly two-thirds of the tissue of the animal body consists of water. Inasmuch as this water is constantly being lost by evaporation from the skin, exhalation by the lungs, and excretion through various organs, it is evident that the loss must be constantly supplied if the functions of life shall be properly performed. It appears probable that certain diseases are at times spread through the agency of insufficient or impure drinking-water. It is, therefore, a matter of very great importance to have a defi- nite notion of what constitutes a pure and sufficient supply of water, and how best to secure it, to be able to detect its condi- tions of purity and impurity, and to know how to maintain the former and avoid the latter. It will be necessary to consider in detail, therefore, the quantity of water required by each indi- vidual for the maintenance of health, the sources whence water is obtained, how it should be collected and stored to the best advantage, the impurities likely to be contained in it, and the methods of keeping it pure, or of purifying it when it has become polluted or vitiated in any manner. THE QUANTITY OF WATER REQUIRED BY HUMAN BEINGS. Dr. Parkes, after a number of experiments, concluded that a man of the English middle class, "who may be taken as a fair type of a cleanly man belonging to a fairly cleanly house- hold," uses about twelve gallons of water per day. This covers all the water needed, including a daily sponge bath. Dr. DeChaumont estimates 1 that 16 gallons should be the daily 1 Parkes' Hygiene, 6th ed., New York, vol. i, p. 5. (49) 50 TEXT-BOOK OF HYGIENE. allowance. By order of the British War Department, 15 gal- lons of water are allowed to each soldier daily. In very many instances this quantity cannot be furnished, but in such cases there necessarily results some deficiency in cleanliness. It is probable that among the poorer classes, especially where a large supply of water is not convenient, the quantity used is not over one-fourth of the above estimate. In estimating the daily supply of water needed in a com- munity, large or small, other circumstances must be taken into consideration in addition to the demands of the individual. For example, in towns or cities allowances must be made for animals, manufacturing purposes, probable waste, fires, sewerage, etc. In cities an allowance of 50 gallons daily per head would not be excessive. In most American cities the supply is much greater. 1 The present daily supply in Baltimore, which is de- rived from an excellent source, is estimated at 60 gallons per head, which could be increased to three times that quantity if necessary. A serious problem, affecting, however, the engineer rather than the sanitarian, is the prevention of waste of water in places where the supply is limited. It is estimated that in Chicago one-half of the water pumped is wasted through negligence and imperfections in the supply apparatus, while in St. Louis the annual cost to the city of the water that is wasted is placed at $400,000. It has been proposed to check this wanton waste by measuring the quantity of water used by each household by means of a meter, as the supply of gas is now measured, and this has been carried into effect in places. There are, however, serious objections to this method. One of the objections is that the very class of persons whom it is desired to induce to use a plentiful supply of water would, from motives of economy, use less than is necessary for cleanliness and health. A system of vigilant inspection of the water service in houses would probably serve to reduce this unnecessary waste to a considerable extent. 1 Buck's Hygiene and Public Health, voL i, p. 214. SOURCES OF DRINKING-WATER. 51 SOURCES OF DRINKING-WATER. All water, from whatever direct source obtained, comes originally, by precipitation, from the atmosphere. In many places the rain- or snow- water is the only source of supply. This is usually collected as it falls upon the roofs of buildings and conveyed by gutters and pipes to cisterns, where it is stored until needed. In Venice, the rain falling upon the streets and court- yards is also collected in cisterns after filtering through sand. The cisterns used for the storage of water in New Orleans and other Southern cities in the United States, where the tempera- ture rarely falls below the freezing-point, are generally con- structed of wood and placed above-ground. Farther north, where it is necessary to protect them against the action of frost, they are placed under-ground. These under-ground cisterns are usually built of brick. The water from cisterns above-ground becomes very much heated in summer, and necessitates the use of large quantities of ice to make it palatable. The water from the under-ground cisterns is pleasantly cool in summer, and is also guarded against freezing in winter, There are, however, very serious objections to storing drinking-water in under-ground cisterns. These reservoirs are usually placed within a few feet of privies and cess-pools, and, as neither the retaining walls of the cisterns nor those of the privies are water-tight, it often happens that the drinking-water becomes strongly impregnated with the soluble portions of the excrement, or the products of its decomposition, which have drained into the cistern. Per- sonal observations in Memphis in 1879, as well as the careful chemical analyses made afterward by Dr. Chas. Smart, U. S. A., 1 have convinced the author that the objections to all under- ground cisterns built of brick, stone, or cement are insuperable from a sanitary point of view. Dr. Smart found over one-half of the under-ground cisterns examined by him in Memphis and 1 Report National Hoard of Health, 1880, pp. 437-441. 52 TEXT-BOOK OF HYGIENE. other cities and towns to be leaky and presenting evidence of organic pollution. The water from 31 out of 80 cisterns ana- lyzed showed decided contamination by sewage. It would seem advisable to prohibit all under-ground cisterns for the storage of drinking-water unless they are constructed of iron, which should be protected against oxidation by a thorough coating of coal- tar. Where any other system of collection and storage is avail- able, however, the under-ground cistern should be unreservedly condemned. Rain-water collected in the country, away from manufac- turing districts, is usually quite pure and wholesome. Its taste is, however, flat and insipid, owing to absence of carbon dioxide and mineral constituents. In cities rain-water frequently con- tains such a large amount of organic matter and other impurities, which have been washed out of the air by the rain, that it may be unfit for drinking. On account of its softness, rain-water is very desirable for washing and other domestic purposes. If the statement made in the last chapter, concerning the presence of organisms in the atmosphere, is remembered, it will be evident on a moment's thought that such organisms, when contained in rain-water, may be the source of disease. The putrefaction which so readily takes place in rain-water upon standing a few days is caused by certain of the organisms carried down out of the lower strata of the air by the descending rain or snow. Precipitation is an exceedingly untrustworthy source of water, and should never be depended upon when other sources of supply are available. Water famines are frequent wherever people are compelled to rely upon such an uncertain source of supply as rain or snow. Rivers and smaller streams probably supply the larger number of cities and towns in this country with drinking-water. When care is taken to prevent the pollution of the stream above the point whence the water is taken, this is usually of fair quality for domestic purposes. When the river can be tapped near its source, or before a large number of manufacturing SOURCES OF DRINKING-WATER. 53 establishments can empty their waste products into its current, or before it receives the sewage of a considerable number of inhabitants living on its banks, the water can generally be re- garded as safe. It is very difficult, however, except in the less settled portions of the country, to find these favorable conditions present. Among the minor objections to the use of river- water for domestic purposes are the liability of most ' streams to become turbid in times of freshet, and the discoloration of the water from dissolved coloring-matters if the stream flows through a marshy or peaty region. These objections are, however, not serious, as nitration will readily remove the suspended matters. The coloring-matter is probably harmless. The organic matter contained in the water of some streams, even when pollution by sewage and manufacturing refuse is absolutely excluded, may, however, be the cause of disease. Dr. Smart has shown 1 that the water from streams in Nebraska, Wyoming, and Utah con- tained organic matter varying in amount from .16 to .28 parts per million. 2 He thinks the so-called "mountain fever" of the Rocky Mountain region is a malarial fever caused by the large amount of organic matter in the drinking-water. Dr. G. M. Kober, U. S. A., states that he has frequently drunk water from mountain streams which had a perceptible taste of cattle-manure, and suggests that as the origin of the ammonia found by Dr. Smart in the water of mountain streams. Dr. Kober also regards the "mountain fever" as a typhoid fever with malarial complications. 3 The most serious objection to the use of river-water for domestic purposes is the employment of streams as carriers of refuse from manufacturing establishments, or of the sewage of cities and towns. In Great Britain and some parts of the con- tinent of Europe, owing to the density of population and the 1 American Journal Med. Sciences, January, 1878, p. 28 et seq. * The source of this organic matter seems to be the melted snow which makes up a large portion of the streams. 3 Report of California State Board of Health for 1886, pp. 48 and 177. 54 TEXT-BOOK OF HYGIENE. variety and extent of manufacturing industries, many of the streams are in an extremely filthy condition. In this country, too, especially in the more thickly settled manufacturing districts of New England, the pollution of rivers has increased to a degree to seriously jeopardize the health of the people who are compelled to draw their water-supply from such streams. Several years since a commission was appointed by the State Board of Health of Massachusetts to inquire into the extent of the pollu- tion of the streams in that State, and to devise means for pre- venting such pollution. The commission extended its inquiries and observations over several years, reporting the result to the State authorities at intervals. 1 It was found that the water of the Blackstone River, at Blackstone, where it crosses the State line and enters Rhode Island, contained over 10 per cent, of sewage and refuse waters. 2 Other streams in Massachusetts show similar pollution. That the presence of such excessive con- tamination renders the water unsuitable for domestic pur- poses must appear evident. It is probable, however, that the most dangerous of the polluting matters are the excreta of human beings, especially those of patients suffering from certain specific diseases, such as typhoid fever or cholera. Only a few years ago it was a generally-accepted theory that running-water, though polluted by sewage, "purifies itself" after flowing a distance of twelve miles, and the comforting and reassuring doctrine is still held by many. Recent observations point to the conclusion, however, that the self-purification of rivers is not entirely to be relied upon. A certain proportion of the sewage, it is true, undergoes oxidation in the presence of light and air and minute organisms, 3 and so becomes changed into other, possibly innocuous compounds. But at present it is not known what proportion or what kind of organic matter does undergo this change. Another portion of the impurities is deposited upon the bottom and sides of the stream, having 1 Reports State Hoard of Health of Massachusetts for 1873, 1874, 1876, 1877, 1878, 1879, 1880. 1 Report State Hoard of Health of Massachusetts, 1876, p. 145. 1 Desinfection, in Eulenburg's Realencyclopaedie d. ges. Heilkunde, vol. iv, p. 68. SOURCES OF DRINKING-WATER. 55 been only held in suspension, and not dissolved in the water. A portion probably forms chemical combinations with other sus- pended or dissolved matters, and is changed into compounds which may be volatile and pass off into the air, or form insoluble precipitates. The remainder is rendered less perceptible or imperceptible to chemical means by dilution. Every stream has sources of inflowing water feeders which increase its volume, and thus dilute any foreign admixture. In view of these facts, the theory of the self-purification of streams, as formerly held, can no longer be regarded as true. But it is unquestionably true that running-water does regain its purity if the inflow of sewage and other refuse is not excessive. It cannot be stated with confidence, however, when a stream, once polluted, becomes fit to use again. Moreover, as it is not possible, by any practicable chemical treatment or filtration on a large scale, to make a polluted water absolutely wholesome, it is safer not to use as a source of domestic supply a stream which is known to have been seriously contaminated by sewage matters or other impurities. The water from fresh- water lakes and ponds is generally to be preferred to river-water for domestic use. It is less liable to become turbid from time to time, and, except in the case of small ponds, inflow of sewage is not likely to cause fouling of the water to any serious extent. When the supply can be drawn from large lakes, as is done in Chicago and other cities on the great lakes of the United States, no purer or better source can be desired. In these cases the point whence the water is taken should be far enough from shore to avoid possibility of sewage contamination. When the water-supply is taken from small ponds, all sewage and waste products from houses and factories must be rigidly excluded ; otherwise, diseases attribu- table to the polluted water are likely to arise among those using the same. The water in small lakes and storage reservoirs sometimes 56 TEXT-BOOK OP HYGIENE. becomes offensive in taste and odor. The water-supplies of several of the large Eastern cities have within the past seven or eight years at times had a peculiar odor and taste somewhat resembling cucumbers. After considerable study, Prof. Ira Remsen, of Baltimore, found the cause of this odor and taste in a minute fresh- water sponge, the Spongilla fluviatilis. A still more offensive odor, tersely described as the " pig-pen odor," is given to the water by the decay of certain species of nostoc and other algae. It is not known that either these vegetable or animal organisms, if present, render the water prejudicial to health. Ponds are often used as sources of ice-supply. It was formerly supposed that in the process of freezing, solid matters in the water were not included in the block of ice when con- gelation occurred. Recent observations have shown the falsity of this assumption. In 1875, an outbreak of acute intestinal disease at Rye Beach, New Hampshire, led to an inquiry by Dr. A. H. Nichols, which disclosed the fact that the ice used contained a large percentage of organic matter. 1 The use of ice from a different source was followed by an almost immediate disappearance of the disease. Upon further investigation it was discovered that the impure ice had been gathered from a small, stagnant pond into which a small brook carried large quantities of saw-dust from several saw-mills. The water of the pond was loaded with organic matter, and in summer the gases of decay arising from it were very offensive. Chemical exam- ination showed that the ice from this pond contained nearly 6 parts of organic matter in 100,000, while in pure ice the organic matter amounted to only .3 part in 100,000. A similar inves- tigation into the character of the ice furnished to the residents of Newport, R. I., was made under the auspices of the Sanitary Protection Association of that city. The ice, which was cut from ponds in the immediate neighborhood of the city, was found to contain an excessive proportion of organic matter. 1 Report Massachusetts State Board of Health, 1876, p. 467. SOURCES OF DRINKING-WATER. 57 Large quantities of sewage and other impurities were discharged into these ponds. 1 A series of experiments recently made by Dr. C. P. Pengra, of Michigan, shows 2 that the purification of the water by freezing is in no sense absolute. In experimenting with bacteria, infusoria, and other organisms, he found that from 9 to 11 per cent, re- mained in the ice and retained their vitality, so that when thawed they rapidly multiplied, and there was no apparent loss of numbers. In the ordinary process of freezing the upper portion is the purest, but if snow or rain fall upon the ice and freeze this upper layer will be found much more impure than the lower. Rational conclusions from these experiments are, that ice should not be gathered from an impure source, and that an early harvest of the ice should be encouraged. In a very recent research, Prudden has shown that typhoid bacilli contained in water are not entirely destroyed by freezing, even after remaining in this condition for 103 days. Springs and wells supply the water for most persons not aggregated in large communities, as cities and towns. Even in the latter no inconsiderable quantity of the water used for drinking and domestic purposes is derived from wells. Spring- water usually comes from a source at a considerable depth below the surface; that is to say, the water has percolated through thick strata of soil before re-appearing at the surface. In its passage through the soil it has lost most of its organic matter, and perhaps taken up mineral and gaseous constituents in larger quantities. It may be so strongly impregnated with the latter as to vitiate it for ordinary use and to render it valuable as a medicine. Ordinarily, however, spring-water is clear, cool, and sparkling, with a refreshing taste and uniform temperature, and is in all respects an agreeable and wholesome beverage. The character of well-water, on the contrary, is often justly open to grave suspicion. Being derived from those strata of the 1 The Dangers of Impure Ice, in The Sanitarian, May, 1882. 2 Private communication to the author. The memoir of Dr. Pengra has been published in the Report of the Michigan State Board of Health for 1884. 58 TEXT-BOOK OF HYGIENE. soil which are most likely to be contaminated by the products of animal and vegetable decomposition, the wholesomeness of the water is inversely proportional to the degree of saturation of the soil with the products of decay. It has been found by experiment that, when organic matter largely diluted witli water is allowed to percolate through soil, it undergoes a gradual decomposition in the presence of certain minute organisms, nitrates and nitrites being formed at the expense of the ammonia and other organic combinations. If, however, the soil is saturated with organic matter in excess, and in a state of concentration, putrefaction takes place, and the conversion of the organic matter into nitrates and nitrites is retarded. Hence, the drain- age of diluted sewage through a stratum of porous soil, not already saturated with putrefying matters, has no especially bad significance, even if the liquid should reach a well used as a source of drinking-water. It is probable that by the time the liquid portion of the sewage reached the well it would have arrived at that point when it could truthfully be termed pure water. At the same time it must be remembered that the puri- fying power of the soil cannot be relied upon if the supply of sewage or other animal or vegetable impurity is too abundant. Distillation is sometimes resorted to for the purpose of pro- curing drinking-water, especially at sea. Vessels now generally carry a still for this purpose. The principal objection to dis- tilled water is its insipidity, due to the absence of carbon dioxide and mineral constituents, which give to good drinking-water its savor. Distilled water may be aerated by passing it in fine streams through holes in the bottom of a cask, elevated so as to allow the water to pass through a considerable stratum of air. Lead is sometimes taken up from the distilling apparatus, and may cause lead poisoning in those using the water. Drinking-water is sometimes procured by melting snow or ice. It is not probable that water derived from these sources is unwholesome, although there is strong popular prejudice against it. Ice and snow may, however, contain large amounts of SOURCES OF DRINKING-WATER. 59 impurities, as already referred to, 1 and be for this reason unfit for use. The following qualities are desirable in water for drinking and domestic purposes : 1. The water should be colorless, transparent, sufficiently aerated, of uniform temperature throughout the year, and with- out odor or decided taste. 2. The mineral constituents (magnesium and lime salts) should not be present in greater proportion than 4 or 6 parts per 100,000. More than this gives to water that quality known as " hardness." 3. There should be but little organic matter present, and no living or dead animal or vegetable organisms. 4. The water should be entirely free from ammonia and nitrous acid, and should contain but very small quantities of nitrates, chlorides, and sulphates. 5. It should contain less than one milligramme of lead per litre. A larger proportion is likely to be followed by lead poisoning. IMPURITIES IN WATER. The transparency and the color of water are affected by the presence of suspended or dissolved mineral or organic mat- ters. If, after standing for a time, the water deposits a sedi- ment, this is dependent upon insoluble matters. If the sediment turns black when heated in a porcelain capsule over an alcohol or gas flame it contains organic matter. If the sediment or residue effervesces upon the addition of hydrochloric acid the presence of carbonates is indicated. Water may be colored by metallic salts or by vegetable matter. It may also contain large quantities of mineral or organic matter, or even living organ- isms, without perceptibly diminishing its transparency. For example, the ova of tape-worms may exist in water in consider- able numbers, and yet remain perfectly invisible except under the microscope. 1 See pages 52 and 53. 60 TEXT-BOOK OF HYGIENE. The presence of sulphur compounds, or of various vege- table and animal organisms (sponges, algae, etc. 1 ), may give to water an unpleasant odor and taste. In the oil regions of this country most of the drinking-water is contaminated with petro- leum, which is very disagreeable to one unaccustomed to it. It is not probable that the small quantities of the oil imbibed with the water have any deleterious influence upon the organism. Many works on hygiene fix a limit to the amount of solid matter allowable in drinking-water. The International Con- gress of Hygiene, at Brussels, fixed the limit at 50 parts in 100,000. It is impossible, however, to say of any particular specimen of water that its content of solid matter, whether or- ganic or mineral, will be prejudicial to health without trial. At the same time it is prudent to reject all waters containing a con- siderable proportion of solid organic matter, as determined by the degree of blackening on heating the sediment or residue after evaporation. The hardness of water is due to the presence of earthy car- bonates, or sulphates, or both. If the hardness is due to car- bonates it is dissipated by heat, as in boiling the water ; the carbon dioxide is driven off, and the base (calcium or magnesium oxide) is precipitated upon the bottom and sides of the vessel. This is termed the "removable hardness." The hardness due to the presence of earthy sulphates is not removed upon heating the water, and is termed the "permanent hardness." The hard- ness depending upon both the carbonates and sulphates is called the " total hardness." The proportion of the above-mentioned earthy salts present in a given specimen of water is determined by what is called the soap test. This test depends upon the property which lime and magnesia salts possess of decomposing soap (oleate and stearate of soda). The quantity of a solution of soap of a definite com- position decomposed by a quantity of hard water indicates the amount of the salts present. In this country and England this 1 See page 52. IMPURITIES IN WATER. 61 is generally expressed in degrees of Clark's scale, which are equivalent to grains of carbonate of lime per imperial gallon. Thus, if the chemist says that a certain sample of water has a total hardness of 16 degrees he means that the earthy salts in the sample decompose the same quantity of soap that would he de- composed by 16 grains of carbonate of lime per imperial gallon. In Germany each degree of the scale used expresses the soap decomposed by 1 part of calcium oxide per 100,000. In the scale used in France each degree corresponds to 1 part of car- bonate of lime in 100,000. So much of the hardness of water as is due to carbonates can be dissipated by boiling, which drives off the free carbon dioxide and allows the insoluble oxides to be deposited as an incrustation upon the bottom and sides of the vessel. The standard soap solution for testing the hardness of water is made as follows : Dissolve 10 grammes of Castile soap in a litre of weak (35 per cent.) alcohol. One cubic centimetre of this solution precipitates 1 milligramme of carbonate of lime. The test is made as follows : To a definitely-measured quantity of water (say 100 cubic centimetres) in a graduated burette a quantity of the soap solution is added and the mixture shaken up; so long as there are dissolved lime or magnesium salts in the water the soap is decomposed and no lather is formed. Soap solution is now added gradually and the shaking repeated until there is evidence of saponification by the formation of a more or less permanent lather or froth. The quantity of soap solution used is noted, and the test is repeated. The mean of the quan- tity of soap solution in cubic centimetres used in the two ex- periments will represent approximately the proportion of salts in grains of carbonate of lime per gallon present, or, as it is gen- erally expressed, in "degrees of hardness." The scale on the following page shows the quantity of soap solution required to decompose the proportion of calcium oxide per 100,000. x 1 Uffelmann, Handbuch der Hygiene, p. 94. 62 TEXT-BOOK OF HYGIENE. TABLE IY. 1 part CaO per 100,000 water requires 5.4 c.cm. standard soap solution. 2 parts " " " " " 9.4 " " " " o tl II II II tl a jg 2 " a " " 4 u it u u u a 17 Q u a a a 5 u u u u u u 20 8 " " " " g u u u u u u 24 4 " " " u g g U (( U U U U 26.2 " " " " 70" " " " 28 " " " " IT 5 u u u " u u 29 8 " " " " O Q U U tl U U U ;; | (; U U it 85" " " " " " 33 3 ' " " u Q Q U U It II U U 35 Q U U U II g 5 a u u u a u gg 7 " " " " ] (I Q u u u a u u 38.4 " " " " 1 5 u u u a u u j(, | u u n it, H Q U It U It U It ^J_g tl tl tt U H 5 u u u u u it 4.3^4. it tt u it 12 o " " " " " " 45 " " " " If there are more than 12 parts of lime in 100,000 the water is diluted with an equal proportion of distilled water and the resultant multiplied by two. Mr. Wynter Blyth has proposed to take the total residue as representing approximately the total hardness of the water, but Dr. Fox points out that there may be a large excess of in- organic solids present in water that is quite soft and originally pure. Hard water is objectionable for domestic use, as it is waste- ful of soap. In cooking certain vegetables, such as peas and beans, the hulls are not thoroughly softened. In making infu- sions of tea and coffee, larger quantities of these materials are needed than where soft water is used. DISEASES DUE TO IMPURE DRINKING-WATER. Hard water is popularly believed to be the cause of calcu- lous diseases, and of goitre and cretinism, but no reliable obser- vations are on record showing that the belief is founded upon DISEASES DUE TO IMPURE DRINKING-WATER. 63 fact. At the same time it is undoubtedly true that calcareous waters produce gastric and intestinal derangements in those unaccustomed to their use. Large amounts of suspended mineral matter are frequently present in river- water, and may give rise to derangements of the digestive organs. If there is carbonate of lime present, the water can be easily clarified by the addition of a small quantity of alum. Sulphate of lime and a bulky precipitate of hydrate of alumina are formed, which carry the suspended matters to the bottom. About 10 centigrammes of crystallized alum are sufficient to clarify a litre of water. This amount of alum is too small to affect the taste of the water perceptibly. This method is frequently used to clarify and render fit for use the water of the Mississippi River, which is usually very muddy. Dr. Parkes quotes the following striking instance of the prac- tical value of clarifying muddy water by means of alum. 1 In 1868 the right wing of the Ninety-second Regiment of High- landers, going up the river Indus, suffered from diarrhoea from the use of the water, which was very muddy. The left wing of the same regiment used water from the same source, but pre- cipitated the suspended matters with alum and had no diarrhoea. The right wing then adopted the same plan with like success. Although the opinion is widespread that water containing much mineral matter, either in- solution or in suspension, is deleterious to health, there is very little evidence absolutely trustworthy upon this point. The presence of large quantities of organic matter in water, whether these matters be of animal or vegetable origin, must always be looked upon with suspicion. The . observation was made by Hippocrates twenty-three centuries ago, that persons using the water from marshes, i.e., water containing vegetable matter, suffer from enlarged spleens. Many physicians, both of ancient and modern times, seem to have held this opinion, but the first positive observation in medical literature is the now 1 Manual of Practical Hygiene, 6th ed., New York, vol i, p. 341. 64 TEXT-BOOK OF HYGIENE. classical one of the ship Argo, reported by Boudin. 1 In 1834 the transport Argo, in company with two other vessels, carried 800 soldiers from Bona, in Algiers, to Marseilles. The troops were all in good health when they left Algiers. All three of the vessels arrived in Marseilles on the same day. In two of them there were 680 men, not one of whom was sick. Out of the remaining 120 men who were on the third vessel, the Argo, 13 died during the passage, and 98 of the 107 survivors suffered from paludal fevers of all forms. None of the crew of the Argo were sick, however. The two vessels exempt from sick- ness, and the crew of the Argo, had been supplied with pure water, while the soldiers on the latter vessel had been furnished with water from a marsh. This water was said to have a dis- agreeable odor and taste. The testimony of a large number of East India physicians is also quoted by Parkes in support of the view that malarial fevers are often caused by impure drink- ing-water. The observations of Dr. Charles Smart, upon the production of "mountain fever" of the Western territories, have already been referred to. The author ventures to state it as his opinion, however, that the instances in which malarial fevers are due to impure drinking-water are very rare. The causation of typhoid fever and cholera by impure drinking-water will be presently referred to. Recently the opinion has been expressed by some that yellow fever and diph- theria are also spread by polluted drinking-water, but no strong evidence has yet been adduced in its support. There can be very little doubt that diarrhoea and dysentery are frequently caused by water which has been contaminated with decaying organic matter. The evidence in favor of this amounts practically to demonstration. It must not be forgotten that the ova of certain animal parasites, such as distoma hematobium, filaria sanguinis hominis, and medinensis, anchylostoma duodenale, and possibly of round- 1 Quoted in Parkes, op. '<., p. 48 ; Nowak, Lehrbuch der Hygiene, p. 51 ; and in numerous other publications on Hygiene. DISEASES DUE TO IMPURE DRINKING-WATER. 65 and tape- worms, for example, are taken into the system along with the drinking-water. Organic detritus of various kinds, sewage, decomposing animal and vegetable matter, refuse from manufacturing estab- lishments, may be a source of pollution of water and render it unfit for drinking or other domestic purposes. It is, however, not certain that water thus rendered unclean is prejudicial to health; in^fact, Dr. Emmerich, of Munich, has recently put his, skepticism on this point to a practical test. For two weeks he drank daily from half a litre to a litre of very filthy water; in fact, nothing less than sewage. The water was both chemically and physically exceedingly impure. Several of the experi- menter's patients partook of the same water without any ill effect. He even claims that a gastric catarrh, from which he was suffering when the experiment was begun, was improved during its course. 1 . The results of Emmerich's experiments, and of other well- known observations, seem almost conclusive that the products of animal and vegetable decomposition, taken into the body with the drinking-water, cannot be looked upon as certainly harmful. Should, however, water containing such impurities, or even water apparently pure, contain the germs of one of the specific diseases, cholera, typhoid fever, or, perhaps, yellow, malarial, or scarlet fevers, or diphtheria, it is probable that such diseases would be communicated to the consumer of the water. Many instances are on record where outbreaks of typhoid fever have been clearly attributable to pollution of the drinking- water by the germ of the disease from a previous case. One of the most remarkable of these outbreaks is that re- corded by Dr. Thorne. 2 About the end of January, 1879, typhoid fever began suddenly in the adjoining towns of Cater- ham and Red Hill. Within six weeks 352 cases occurred. All 1 Wolffhuejrel : Wasserversorgung, in Pettenkofer u. Ziemssen's Handbuch der Hygiene, I Abth., II Hlfte, p. 97. - Rcp ( >''t of the medical officer totlie Local (iovernment Hoard for 1879. Quoted in Fa- don Hygienisuhe Untersuchungen, etc., II Abtli., p. 261. 66 TEXT-BOOK OF HYGIENE. other sources of the disease were excluded except the drinking- water, to pollution of which it was traced with almost absolute certainty. Caterham contained 558 houses and Red Hill 1700. Of the former 419 and of the latter 924 drew their drinking- water from a common supply, having its source in a well several hundred feet deep. The insane asylum, with 2000 inmates, and the military barracks in Caterham used water from a private .well. There was no typhoid fever among the last two commu- nities. During January one of the workmen engaged in some excavation near the public well was taken ill with diarrhoea and fever, probably typhoid, but was still able to continue his work. His dejections were often voided where they were cer- tain to become mingled with the water of the common supply. This man's diarrhoea began on January 5th and continued until the 20th of the month, during which time he remained at work. On the latter date he was compelled to quit work and take to his bed. Exactly two weeks from the beginning of the man's sickness, on January 19th, the first case of typhoid occurred in Caterham, and then rapidly increased. The first case occurred, therefore, just fourteen days the incubative period of typhoid after the presumed infection of the drinking-water by the de- jections of the sick laborer, who had come from Croydon, where typhoid fever was at the time prevalent. Within two weeks from the appearance of the first case the epidemic had reached its height, and then rapidly declined, disappearing almost entirely hi a month after the outbreak. It was shown by Dr. Thome that nearly all the houses in which the disease appeared were sup- plied with water from the source above mentioned, while other houses in the immediate vicinity of the infected ones remained free from the disease. In 1874 there was an outbreak of typhoid fever in the town of Over Darwen, in which nearly 10 per cent, of the in- habitants were attacked. Here the source of the disease was also traced to an infected water-supply. Dr. Buchanan has shown that an outbreak among the stu- DISEASES DUE TO IMPURE DRINKING-WATER. 67 dents of the University of Cambridge was likewise attributable to an infected water-supply. In this country the reports of the Boards of Health of the various States teem with accounts of localized outbreaks of typhoid fever, referred to infected or polluted drinking-water. In most instances the evidence furnished by the observers is not conclusive. In many, however, especially of those found in the Massachusetts and Michigan reports, the fact of the communi- cation of the disease in this manner seems unquestionable. One of these is as follows : Out of 40 families, all using water from a certain well, there occurred 23 cases of typhoid fever. Out of 47 families, living in the same neighborhood, but using water from different sources, only 2 had typhoid fever. 1 Dr. C. F. Folsom has published a very suggestive account of a house epidemic, 2 where 9 persons in a single house, who all drank water from a well which was proven to be infected from a privy, were attacked by this disease. In 1885 an epidemic of typhoid fever began in Plymouth, a mining town of 8000 or 9000 inhabitants, situated in the Wyoming coal region of Pennsylvania, and on the right bank of the Susquehanna River. The epidemic began in April, and lasted until the ensuing September. There were 1104 persons attacked by the disease, of which number 114, or 10.3 per cent., died. The careful inspection made into the history of this epidemic revealed the fact that the public water-supply had unquestionably become polluted by the faecal discharges of typhoid-fever patients, and the entire course of the disease, in this instance, is in complete accord with the view that the origin and spread of the epidemic were due to the pollution of the drinking-water with the typhoid-fever poison. In addition, Chantemesse and Vidal have demonstrated the presence of the bacillus of Eberth, which is now generally rec- ognized as the cause of typhoid fever, in drinking-water from 1 Transactions Mich. Med. Society, p. 401, 1883. Boston Med. and Surg. Journal, vol. cii, pp. 227, 261. 68 TEXT-BOOK OF HYGIENE. a well near Paris, to which a small outbreak of typhoid had been traced. This demonstration has also been furnished bv Prof. V. C. Vaughan, in connection with an outbreak of the same disease in the State of Michigan. The numerous cases of typhoid fever which have been attributed to the use of infected milk may be included in this category. It is probable that the milk became infected either through polluted water used for the purpose of cleansing the milk-vessels or in diluting the milk. Mr. Ernest Hart has re- corded 1 50 epidemics of typhoid fever, 15 of scarlet fever, and 7 of diphtheria, the cause of which he has attributed to infected milk. It is probable that typhoid fever is, in the majority of cases, spread through the medium of polluted drinking-water, and, in many of the instances on record, the relations between cause and effect impure water and typhoid fever have been so clearly made out as to no longer permit any doubt upon the question. As it is with typhoid fever, so also with cholera. In a later chapter the origin and propagation of typhoid fever and cholera will be discussed more fully. At the present time only the rela- tions of the drinking-water to the spread of these diseases can be considered. In the instance to be presently noted the con- nection between the infected water, on one hand, and the out- break of cholera, on the other, is so clearly shown as to be almost equivalent to a mathematical demonstration. The facts in the case were brought to light after a patient inquiry by a commission, whose report drawn up by Mr. John Marshall has made the occurrence classical. In 1854 the people of a well-to- do and otherwise healthy district in the eastern part of London suffered severely from cholera. Upon inquiry the fact was elicited that a child had died of cholera at No. 40 Broad Street, and that its excreta had been emptied into a cess-pool situated only three feet from the well of a public pump in that street, from which most of the neighboring people took their drinking- 1 Transactions Seventh Int. Med. Congress, vol. iv, p. 391, 1881. DISEASES DUE TO IMPURE DRINKING-WATER. 69 water. It was further discovered that the bricks of the cess- pool wall were loose and permitted its contents to drain into the pump-well. (It should be noted that the communication between the cess-pool and well was direct ; that there was im- mediate drainage, not percolation through the soil.) In one day 140 to 150 people were attacked, and it was found that nearly all the persons who had the malady during the first few days of the outbreak drank the water from the pump. When the pump was closed to public use by the authorities the epi- demic subsided. The most singular case connected with this outbreak was the following : In West End, Hampstead, several miles away from Broad Street, there occurred a fatal case of cholera in a woman 59 years old. This woman formerly lived in Broad Street, but had not been there for many months. A cart, however, went daily from Broad Street to West End, carrying, among other things, a large bottle of water from the pump referred to. The old lady preferred this water to all others, and secured a daily supply in the manner stated. A niece, who was on a visit to the old lady, drank of the same water. She returned to her home, in a high and healthy part of Islington, was likewise attacked by cholera and died. There were, at this time, no other cases of cholera at West End, nor in the neighborhood of these last two persons attacked. Most of the English medical officers in India hold strongly to the view that cholera is spread by polluted drinking-water, and the evidence in its favor is very strong. Quite recently (in 1885) Dr. Robert Koch discovered the cholera spirillum in a water-tank in Calcutta, used as a source of domestic supply, and in this way furnished another link in the chain of evidence connecting the spirillum, the drinking- water, and the outbreak of the disease. The evidence in favor of the influence of impure drinking- water on the causation of other diseases than those mentioned is not sufficient to justify any conclusions at present. The source of a water-supply may be pure, yet pollution 70 TEXT-BOOK OF HYGIENE. may occur before the water is used by the persons to whom it is distributed. Supply-pipes may become defective, and the water become contaminated with sewage or other deleterious substances. It is a current belief that no impurity can gain access to hydrant-pipes between the reservoir, or source of supply, and the point of discharge of the water. Nevertheless, such contamination may occur very readily. The author and his colleague, Dr. J. W. Chambers, of Baltimore, proved this conclusively a few years ago by establishing an undoubted con- nection between a house-epidemic of typhoid fever and a defect in the hydrant supplying the family with water. 1 The hydrant was one of the class known as Clark's patent non-freezing hydrant. The mechanism of these hydrants is as follows : At the lower end of the vertical discharge-pipe is a glazed earthen- ware plunger, which works through a ring of rubber packing into a vacuum chamber. At the bottom of the vacuum chamber is a valve regulating the entrance of the water from the con- ducting-pipe. When the water is shut off this valve is kept closed by a spiral spring. When the crank of the hydrant is turned forward that is, when the water is "turned on" the plunger is forced to the bottom of the vacuum chamber, presses on the spring, opens the valve, and allows the water to dis- charge. When the crank is turned back the plunger is raised, releases the spiral spring, which forces the valve into its bed, and shuts off the water. The partial vacuum produced by the raising of the plunger draws the water, which is in the vertical discharge-pipe, into the vacuum chamber, which is so far below the surface as to be unaffected by frost. In course of time, and with use, the rubber packing gets worn and permits gradual leakage into the vacuum chamber of the dirty stagnant water by which this part of the hydrant is always surrounded. Out- breaks of typhoid fever having a similar origin, 2 in which the 1 On Preventable Pollution of Hydrant- Water and its Relation to the Spread of Ty- phoid Fever. Maryland Meil. Journal, vol. vii, p. 271. * Local Causes of Insanitation in Baltimore, by John Morris, M.D. Report Md. State Board of Health, 1878. DISEASES DUE TO IMPURE DRINKING-WATER. 71 connection between cause and effect was clearly shown, have been reported by other physicians of the same city. Aside from the practical question of the causation of disease by polluted water, a more abstract and aesthetic idea is involved in consciously taking any impurity into the system. The in- stincts of man, as well as of most animals, revolt at it. These inborn instincts, which constitute the sanitary conscience, as Soyka says, demand purity of food and water, as they insist on cleanliness of the body, of clothing, and of the dwelling. STORAGE AND PURIFICATION OF WATER. Wherever a large supply of water is needed, unless drawn direct from a well or spring, or pumped directly from its source, arrangements for storage are necessary. Cisterns and large reservoirs are made use of for this purpose. River-water, espe- cially, requires a period of rest in a storage reservoir in order to allow deposition of the large amount of suspended matter in it. Prolonged storage also gives opportunity for the conversion of possibly deleterious organic compounds into simple and perhaps harmless combinations. Usually, in an elaborate system of water- works, a series of reservoirs is built, in which the water is stored successively, so that before its final distribution through the street-mains it has become quite clear and pure. Filtration on a large scale is also used in connection with storage reservoirs in order to secure greater purity of the water. In the distribution of water, care should be taken that nothing deleterious is taken up by the water in its passage through the pipes. Lead poisoning is not infrequent from drinking-water that has passed through a long reach of lead pipe, or which has been standing in a vessel lined with lead. Tanks and storage cisterns should therefore not be lined with lead, and the use of lead pipe in the supply service should be avoided as much as possible. Fortunately, most natural waters possess a considerable propor- tion of carbon dioxide, which forms with the lead an almost insoluble carbonate of lead. This carbonate of lead is deposited 72 TEXT-BOOK OF HYGIENE. on the inside of the pipes, and protects both the pipes against erosive action from other constituents of the water, and also prevents the contamination of the water by the lead. An -excess of carbon dioxide in the water renders this deposit soluble, and may cause serious poisoning. Any water which is shown by analysis to contain over 1 milligramme of lead per 100,000 is dangerous, and should be rejected. Owing to the possibility of defilement of the water from improper construction of hydrants, all outdoor hydrants should be discouraged as much as possible, and should be replaced by a simple tap-cock indoors. The pipes should also be laid deep enough under-ground, or otherwise protected against freezing in winter. A number of methods, all more or less efficient, have been introduced to purify water when it needs purification before being fit for use. These methods either comprise filtration or seek to purify the water without the aid of this process. One of the methods of purification without filtration consists in exposing the water to the air in small streams. This was pro- posed by Lind more than a century ago, and has since been frequently revived. The water is passed through a sieve, or a perforated tin or wooden plate, so as to cause it to fall for a distance through the air in finely-divided currents. By this process sulphuretted hydrogen, offensive organic vapors, and possibly dissolved organic matters are removed. This process has been used in Russia on a large scale. By boiling and agitation, carbonate of lime, sulphuretted hydrogen, and organic matter are removed or rendered innocuous. Vegetable germs are usually destroyed, although Tyndall has shown that some bacterial germs withstand a temperature higher than that of boiling water. Pathogenic germs are, however, all destroyed by boiling water acting upon them for ten minutes, as shown by Dr. G. M. Sternberg. 1 As has already been mentioned, 2 alum is one of the readiest 1 Report of Committee on Disinfectants, 1888. * See page 59. STORAGE AND PURIFICATION OF WATER. 73 and most efficient means of removing suspended matters from water. Permanganate of potassium is sometimes used to purify water containing considerable organic matter. The perman- ganate rapidly oxidizes the organic matter, and is believed to render it harmless. There is no certainty, however, that the germs of specific diseases are destroyed by the action of this salt, in the proportion in which it could be used for the purposes of water purification. A yellow tint is given to the water by the permanganate, which is due to finely-divided peroxide of manganese. This does no harm, but is unpleasant. Water unfitted for use by organic matter is sometimes rendered usable by infusing certain vegetable astringents in it. Thus, it is said that in certain parts of China, where the water contains large quantities of organic matter, the inhabitants drink water only in the form of tea. The tannin of the tea-leaves precipitates the suspended matters and renders the water fit for use. Mixing the water with red wine, which is astringent, has the same effect. 1 Filtration is an efficient means of removing suspended matters. Charcoal, sand, gravel, and spongy iron are used as filtering material. A most economical filter is one made of fine, clean sand, above which layers of gravel of a gradually-increasing size are placed. The coarser particles of suspended matter are arrested before the sand, which removes most of the coloring and organic matters, is reached. Filters easily become fouled by the matters arrested in the interstices of the filtering material, and hence require frequent renewal or cleansing. A cheap and efficient filter is made by placing a sheet of druggists' filtering-paper in a glass funnel and filtering the water through it. A now and clean sheet of paper should be used every day. M. Chamberland has invented a filter which is said to be 1 Champouillon, quoted in Mod. and Surg. Hist, of the War, part ii med. vol., p. 613. 74 TEXT-BOOK OF HYGIENE. absolutely germ-proof, but this power is not permanent, as after a week micro-organisms pass through the filtering material. The same is true of all other niters hitherto invented. TESTS FOR IMPURITIES IN WATER. Accurate and reliable quantitative analyses of water can only be made by chemists of experience. Every intelligent person should, however, know how to determine the presence or absence of suspected impurities. The following methods are simple, and easily carried out: The color, transparency, and odor of water are determined by the unaided senses. As a standard for comparison in making the color test, pure, distilled water may be used. Two tubes of clear, white glass, 61 centimetres long, are filled with distilled water and with the specimen to be tested, and placed side by side upon a sheet of white paper. The tops of the tubes are covered with little squares of clear glass. The color is noted by com- paring the tints of the water in the two tubes. The same procedure may be used to determine the transparency of the water. While the color and turbidity show impurities, these are not necessarily prejudicial to health; on the other hand, the clearest and most sparkling water may contain so much poisonous matter as to be positively dangerous. The odor of the water is best ascertained by heating a small quantity in a narrow-necked flask to 40 to 45 C. (104 to 113 F.), and then taking a few strong whiffs at the flask. The odor may or may not indicate the presence of deleterious substances. The chemical examination of a water for sanitary purposes, short of a complete analysis, comprises the determination of the presence or absence of suspected impurities; in other words, it may be termed a qualitative analysis. In some cases an approxi- mate quantitative examination may also be made with little more trouble and skill. TESTS FOR IMPURITIES IN WATER. 75 The examination may be divided into the following pro- cedures : 1. The determination of the total residue. * 2. The determination of the presence of (a) Organic matter. (6) Chlorides. (c) Nitrogen compounds. (d) Mineral poisons. Determination of Total Solids. Examination of the public water-supply of eight large cities in the United States shows that the total solid residue varies from 6 to 16 parts in 100,000. The total solids of a good drinking-water should not exceed 25 to 30 parts per 100,000, although a larger quantity may be present without being harmful. The method of determining the total solids is to evaporate a definite quantity say, 70 cubic centimetres of the water in a previously-weighed platinum dish to dryness over a water-bath. The dish is then wiped dry and weighed again. The difference in weight between the empty dish and the latter with the dry residue represents the proportion of the latter in grains per gallon. To convert this figure into parts per 100,000 the number of grains per gallon is divided by .7. For example, if the number of grains of solid residue in the specimen examined is 22.4, then 22.4 -f- .7 = 32 parts per 100,000. Determination of Organic Matter. This is the most difficult test to apply in the sanitary examination of water. While it is comparatively easy to determine the presence of organic matter, its quantity and nature are exceedingly complex problems to solve. The presence of organic impurity in water may be detected by the permanganate-of-potash test, the nitrate-of-silver test, and the incineration test. Neither of these processes is compe- tent 'to differentiate noxious from inoffensive organic matter. The permanganate test, modified by Dr. DeChaumont, is the 76 TEXT-BOOK OF HYGIENE. one usually adopted. The process is as follows: To 250 cubic centimetres of the water to be examined add 5 cubic centimetres of dilute sulphuric acid (10 per cent.) in a clear, white glass flask. Then add permanganate of potassium solution (395 milligrammes to 1 litre of distilled water) until the water has taken a pink tinge. Heat the water to 140 F. (60 C.), adding permanganate solution if the color disappears. When the tem- perature above mentioned is reached remove the flask from the burner, and add permanganate drop by drop until a faint .pink color is obtained, which remains permanent for ten minutes. Read off the number of cubic centimetres of the permanganate solution used as required for total oxidizable matter. As the solution of permanganate yields in presence of an acid 0.1 of a milligramme of oxygen for each cubic centimetre, it is evident that the number of cubic centimetres of solution decomposed has furnished an equal number of tenths of a milligramme of oxygen which has entered into other combinations. But, inasmuch as all the oxidizable matter in the water may not be organic, the inorganic oxidizable matter (nitrous acid) must be separated. This is done by first boiling the water with sulphuric acid, as above (250 cubic centimetres -f- 5 cubic centimetres), for twenty minutes, to remove the nitrous acid. Then allow the acidulated water to cool down to 60 degrees and add the permanganate until a pink color is obtained for ten minutes. The amount of permanganate solution used gives the number of milligrammes of oxygen required for oxidizable organic matter. Determination of Chlorides. Chlorine, or its compounds, when present in drinking-water, represent generally sewage pollution. It is true that chlorine may be in excess in water, and the latter, nevertheless, be entirely free from sewage or urine, but this occurs only where there is a natural deposit of chlorine compounds in the soil from which the supply is drawn. If communication with the sea or salt-deposits is excluded, the chlorine may be assumed to be due to the inflow of sewage. TESTS FOR IMPURITIES IN WATER. 77 Especially is this the case if the test for organic matter has given positive results. The proportion of chlorine may be estimated thus: Place 70 cubic centimetres of the water into an evapo- rating dish, and add a small fragment of neutral chromate of potash. Then, by means of a pipette .graduated to tenths of a cubic centimetre, standard solution of nitrate of silver 1 should be allowed to drop into the water until the red color produced remains permanent. The number of cubic centimetres of the silver solution required to produce the permanent red tint is equivalent to the number of grains of chlorine per gallon, which, if divided by .7, gives the parts per 100,000. Another method of determining the presence of chlorine or chlorides is as follows: Acidulate about 16 cubic centimetres of the water to be tested with pure nitric acid, and add a few drops of a solution of nitrate of silver (1.5 grammes to 32 cubic cen- timetres of distilled water). A white precipitate, gradually changing to gray, is produced if chlorides are present. The degree of cloudiness produced will indicate approximately the amount of chlorides: "1.5 parts of chlorine per 100,000 give a haze; 5.7 parts per 100,000 give a marked turbidity; 14 parts per 100,000, considerable precipitate." If the chlorine is found by this test to exceed 1.5 parts per 100,000, the source of the contamination should be searched for. If drainage from a cess- pool is suspected, a quantity of salt water may be thrown into it, and the water again tested after an interval of four hours to see whether the chlorine has increased. Determination of Nitrites and Nitrates. The presence of these nitrogen compounds in drinking-water should excite sus- picion of sewage contamination. They are the resultants of oxidation of nitrogenous organic matter, and, although water containing them is not necessarily dangerous, their presence should render a thorough examination of the source of supply imperative. 1 Standard Solution of Nitrate of Silver. Dissolve 4.79 grammes of crystallized nitrate of silver in 1 litre of distilled water. One cubic centimetre of this solution precipitates 1 milli- gramme of chlorine. 78 TEXT-BOOK OF HYGIENE. The readiest method of detecting nitrates and nitrites in water is by the pyrogallol test. This may be performed as fol- lows : Put 2 cubic centimetres of pure sulphuric acid in a small test-tube and add 1 cubic centimetre of the water to be tested. To this mixture is added 1 drop of a solution of pyrogallol (65 centigrammes to 30 cubic centimetres) in distilled water, acidulated with 2 drops of sulphuric acid. The water becomes colored a dark amethyst or wine brown if the salts are present. The depth of color indicates approximately the amount of the impurity. The following test for nitric acid or nitrates may also be used : A small quantity of the water is evaporated to dryness, and a few drops of a solution of carbolic acid in 4 parts of con- centrated sulphuric acid and 2 parts of distilled water added to the residue. If nitric acid is present, a brownish-red color results, which turns green and then yellow upon the addition of ammonia. Nitrous acid or nitrites will give a reaction with iodide of potassium and starch ; 350 to 600 cubic centimetres of water in a flask are acidulated with a few drops of dilute sulphuric acid, and a little solution of iodide of potassium added. About 2 grammes of freshly-prepared starch are added and the mixture shaken. If nitrous acid is present, the iodide is decomposed, setting free the iodine, which combines with the starch, causing a blue color. The test is a very delicate one. Ammonia. The presence of this is determined by Nessler's reagent, 1 as follows: 100 cubic centimetres of the water to be examined is treated with 0.5 cubic centimetre of caustic soda solution and 1 cubic centimetre of carbonate of soda solution to precipitate the earthy salts. After the precipitate has sub- sided, 1 cubic centimetre of Nessler's reagent is added. If ammonia is present the water takes a yellowish tint. 1 Nessler's Reagent. Dissolve by heating and stirring 35 grammes of potassium iodide and 13 grammes of mercuric chloride in 800 cubic centimetres of distilled water. Add gradually a cold aqueous saturated solution of mercuric chloride until the red color produced just begins to be permanent ; 160 grammes of solid caustic potash are then added to the mixture which is to be diluted with distilled water until it exactly measures one litre. TESTS FOR IMPURITIES IN WATER. 79 Determination of Mineral Poisons. Of these the most important are lead, copper, zinc, and arsenic. The presence of any of these in even the smallest quantity is dangerous, and, if constant, the water so contaminated should not be used for drinking purposes. In order to detect lead 250 cubic centimetres of the water is first treated with hydrochloric acid, and then sulphuretted hydrogen (in aqueous solution) is added. If a brownish or black precipitate results, either lead or copper may be present. On filtering the water, dissolving the residue in hot, diluted nitric acid, and adding a solution of potassium bichromate, a yellow precipitate, soluble in caustic potash, is thrown down if lead is present. If the precipitate produced by sulphuretted hydrogen is dissolved, as above, and ammonia added, a blue color is produced in the presence of copper. To detect zinc the sulphuretted hydrogen precipitate is treated with caustic soda, again filtered, and sulphuretted hydrogen added to the filtering liquid. A white precipitate indicates the presence of zinc. Arsenic is detected by Marsh's test. Mr. A. J. Cooper has prepared the following table showing the accuracy of certain tests employed for the determination of poisonous metals in drinking-water : TABLE Y. Metal. Reagent. Depth of Liquid, 3% Inches. Depth of Liquid, 14J^ Inches (cylinder inclosed in opaque tube). 1 part of metal detected in 1 part of metal detected in Copper K 4 Cy 6 Fe 4,000,000 of water. 11,750,000 of water. Copper NH 4 HO 1,000.000 1,950,000 ' Copper H.8 4,150,000 15,660,000 ' Zinc . NH 4 HS 2,500,000 Arsenic H 2 S 3,600,000 7,520,000 ' Lead . K 2 CrO 4 4,000,000 5,875,000 ' Lead . H 2 S 100,000,000 196,000,000 In making the tests a tall glass is used, and the formation of the precipitate observed by looking down perpendicularly through the column of liquid of 3f inches (95 millimetres) and 14J inches (368 millimetres) respectively. TEXT-BOOK OF HYGIENE. SIGNIFICATION OF THE VARIOUS IMPURITIES INDICATED BY THE FOREGOING TESTS. The following summary gives, briefly, the inferences that may be drawn from the result of the foregoing tests 1 : " If chlorine be present in considerable quantity it either comes from strata containing chloride of sodium or calcium, from impregnation of sea- water, or from admixture of liquid excreta of men and animals. In the first case the water is often alkaline from sodium carbonate ; there is an absence, or nearly so, of oxidized organic matters, as indicated by nitric and nitrous acids and ammonia, and of organic matter; there is often much sulphuric acid. If it be from calcium chloride there is a large precipitate with ammonium oxalate after boiling. If the chlorine be from impregnation with sea-water, it is often in very large quantity ; there is much magnesia, and little evidence of oxidized products from organic matters. If from sewage the chlorine is marked, and there is coincident evidence of nitric and nitrous acids and ammonia, and if the contamination be recent of oxidizable organic matters. "Ammonia is almost always present in very small quan- tity, but if it be in large enough amount to be detected without distillation it is suspicious. If nitrates, etc., be also present, it is likely to be from animal substances, excreta, etc. Nitrates and nitrites indicate previously-existing organic matters, prob- ably animal, but nitrates may also arise from vegetable matter, although this is probably less usual. If nitrites largely exist it is generally supposed that the contamination is recent ; the co- incidence of easily-oxidized organic matters, of ammonia, and of chlorine in some quantity, would be in favor of an animal origin. If a water gives the test of nitric acid, but not of nitrous acid, and very little ammonia, either potassium, sodium, or calcium nitrate is present, derived from soil impregnated with animal substances at some anterior date. If nitrites are 1 Parkes' Hygiene, vol. i, p. 79. SIGNIFICATION OF VARIOUS IMPURITIES. 81 present at first, and after a few days disappear, this arises from continued oxidation into nitrates ; if nitrates disappear it seems probable this is caused by the action of bacteria or other, low forms of life. Sometimes in such a case nitrites may be formed from the nitrates. Lime in large quantity indicates calcium car- bonate if boiling removes the lime, sulphate or chloride or ni- trate if boiling has little effect. Testing for calcium carbonate is important in connection with purification with alum. Sul- phuric acid in large quantity, with little lime, indicate sulphate of sodium, and usually much chloride and carbonate of sodium are also present, and on evaporation the water is alkaline. Large evidence of nitric acid, with little evidence of organic matter, indicates old contamination ; if the organic matter be large, and especially if there be nitrous acid as well as nitric present, the impregnation is recent." THE BIOLOGICAL OR BACTERIOLOGICAL EXAMINATION OF DRINKING- WATER. Since the development of the methods of cultivation of micro-organisms by Koch and his pupils, and their employment for the study of water pollution by Meade Bolton, Wolff hiigel and Riedel, Percy Frankland, Prudden, and others, and the un- satisfactory results of chemical analysis, some sanitarians have expressed the conviction that the biological method is the only exact one for determining water pollution from a sanitary point of view. While this may be conceded, it is also true that very few health officers are competent to give an expert opinion upon the nature of the organisms which may be found in the water examined. It requires but little technical skill to make cultiva- tions of bacteria from samples of water, but only an expert bacteriologist may safely pronounce upon the nature of the organisms constituting the various colonies which develop upon the nutritive gelatin. Just as the mere presence of organic matter as determined by the chemist is not indicative of a dan- gerous quality in the water unless the kind of organic matter 82 TEXT-BOOK OF HYGIENE. and its derivation be also specified, so likewise the presence of bacteria alone is of small significance ; the danger consists not in bacteria, but in certain kinds of bacteria. The differential diagnosis is possible only to the trained bacteriologist. While, as stated, a positive decision as to the sanitary value of a water may often be impossible, there are certain chemical and microscopical features which stamp a water as good or bad. Dr. DeChaumont gives an approximate valuation which may often serve as a useful guide. 1 He classifies water under the four heads of Pure and Wholesome Water, Usable Water, Suspicious Water, and Im- pure Water. The characters of these waters are arranged in a series of tables, the essential details of which are given in Table VI. TABLE VI. CHEMICAL PUKE WATER. USABLE WATER. SUSPICIOUS WATER. IMPURE WATER. CONSTITUENTS. I. Parts in 100,000. II. Parts in 100,000. m. Parts in 100,000. IV. Parts in 100,000. Chlorine in solution . Under 1.4000 Under 4.2857 4-7 Above 7.142S Solids " total . " 7.1428 " 42.8571 43-71 71.4285 " " volatile " 1.4000 " 4.2857 4-7 7.1428 Ammonia, free or sa- line " 0.0020 " 0.0050 0.0050-0.0100 0.0100 Ammonia, albuminoid " 0.0050 " 0.0100 0.0100-0.0125 0.0125 Nitric acid in nitrates " 0.0323 " 0.5000 0.5-1.0 1 0000 " " nitrites Nil. Nil. 0.0500 0.0500 Nitrogen in nitrates . " 0.0140 " 0.1129 0.1243-0.2373 2415 Total nitrogen . . . " 0.0230 " 0.1252 0.1255-0.2465 0.2(501 Oxygen absorbed by permanganate and acid within half an hour at 140 F. . . " 0.0250 " 0.1000 0.1000-0.1500 " 0.1500 Total hardness . . . " 8.5 " 17.3 Above 17.0 " 28.5 Permanent hardness . " 3.0 " 5.7 " 5.7 " 8.7 Phosphoric acid in phosphates . . . Traces. Traces. Heavy traces. Heavy traces. Sulphuric acid in sul- phates Under 3.000 Above 3.000 Above 4.2857 Heavy metals . . . Nil. Traces. Traces. ( Any except | iron. Hydrogen sulphide . " Nil. Nil. Present. Alkaline sulphides 1 Parkes' Hygiene, vol. i, pp. 103-106. EXAMINATION OF DRINKING-WATER. 83 PHYSICAL CHARACTERS. No. I. Colorless, or bluish tint ; trans- parent, sparkling, and well aerated ; no sediment visible to naked eye ; no smell ; taste palatable. No. II. Colorless, or slightly greenish tint ; transparent, sparkling, and well aerated ; no suspended matter, or else easily separated by coarse filtration or subsidence ; no smell ; taste palatable. No. III. Yellow, or strong, green color ; turbid ; suspended matter con- siderable ; no smell, but any marked taste. No. IV. Color, yellow or brown ; tur- bid, and not easily purified by coarse filtration ; large amount of suspended matter ; any marked smell or taste. MICROSCOPICAL CHARACTERS. No. I. Mineral matter ; vegetable forms with endochrome; large animal forms ; no organic debris. No. II. Same as No. I. No. III. Vegetable and animal forms more or less pale and colorless ; organic debris ; fibres of clothing, or other evi- dences of house-refuse. No. IV. Bacteria of any kind ; fungi ; numerous vegetable and animal forms of low types ; epithelia, or other animal structures ; evidences of sewage ; ova of parasites, etc. [The following works are recommended to those desiring fuller information upon the subjects embraced in the foregoing chapter : Water Supply, by Wm. Ripley Nichols, N. Y., 1884. A Guide to the Microscopic Examination of Drinking- Water, by J. D. MacDonald, R.N.F.R.S. Sanitary Examinations of Water, Air, and Food, by Fox. Report of the Committee on Water Pollution, Public Health, vol. xiv. Zeitschr. f. Hygiene, vol. i, by Bolton. Prudden in N. Y. Medical Record, 1887. Arb. aus d. Reichsgesundheitsamte, I, Wolffhiigel and Riedel. Kenwood : The Hygienic Laboratory, Part I.] QUESTIONS TO CHAPTER II. WATER. For what purposes do people need water? Why should the supply be pure? What is the quantity needed by each person daily, and what quantity should be supplied per head in towns and cities for all purposes ? How may waste of water be prevented ? What is the objection to the use of water-meters ? What is the original source of all fresh water? How is rain-water usually collected and stored? What are the objections to underground cisterns? What is the only material of which underground cisterns should be made ? What impurities may rain-water contain ? Why is it so valuable for domestic purposes? What is the great objection to the use of rain- water ? From what source do most cities and towns derive their water- supply ? What precautions must be observed regarding such a source ? What are some of the minor objections to the use of river-water? What peculiar diseases ma3 T be due to such water? What is the most serious objection to the use of river-water for domestic purposes? How does a running stream purify itself? Can this self-purification be relied upon? Can it be stated definitely when a stream once polluted becomes fit for use again ? Is it safe to use water from a stream known to have been contaminated by sewage ? What is usually the quality of water from fresh-water lakes and ponds ? What large city uses lake-water entirely ? What precautions must be observed regarding such .a source of supply? To what is the offensive taste and odor of water from small lakes or storage-reservoirs often due ? Does water purify itself absolutely in freezing ? What matters may be found in ice ? Are all pathogenic micro-organisms destroyed by freezing ? What part of ice is the purest ? What class of persons usually derive their drinking-water from springs and wells ? What is the relative purity of spring- and of well- water ? Why ? AYhat changes take place in diluted organic matter in percolating through the soil? To what are these changes due? What mav retard or check these changes ? Is water containing nitrites and (84) QUESTIONS TO CHAPTER II. 85 nitrates necessarily dangerous ? Of what are nitrites and nitrates an indication ? What is the principal objection to the use of distilled water as a beverage, and how may this objection be overcome? What metallic poison may be taken up from the distilling apparatus ? Name some of the qualities that are desirable in water for drinking or domestic purposes. When is a water said to be hard ? What may affect the color and transparency of water ? Of what may the sediment in water be composed ? What impurities may there be in perfectly colorless and transparent water ? How may the presence of sulphur compounds be detected ? What is the usual amount of solid matter permissible in water. What class of solid constituents especially should cause a water to be rejected ? To what is the hardness of water due? What is the distinction between " removable " or u temporary " and " permanent " hardness, and what is meant by " total " hardness ? How is the degree of hard- ness determined, and upon what does the test depend ? Describe the test. What is meant by Clark's scale ? Why is hard water objection- able for domestic use ? What diseases and derangements of health may be due to hard water? Is the evidence absolute regarding all of these? What troubles may large amounts of suspended mineral matter cause? How may such water be clarified ? What mineral in the water is essential to the process ? What may be the effect of large quantities of organic matter in the water? What infectious diseases may be due to impure drinking-water? What other organisms harmful to health, other than bacteria, may be found in drinking-water? Name some notable places where epidemics have been undoubtedly caused by impure drinking-water. How may a milk-supply be infected by impure water? How might a water be pol- luted in distribution, even though the source be pure? What is the advantage of a prolonged storage of river-water? What waters should not be stored in lead-lined cisterns or conveyed in leaden pipes ? What is the greatest amount of lead permissible in water ? In what ways may water be purified on a large scale ? How may the hardness of water be partially removed ? What methods may be used in the household for the purification of water ? How may the water be softened ? How may disease germs and other organisms in water be destroyed ? How may organic matter be removed ? What are some good filtering materials ? What are some of 86 QUESTIONS TO CHAPTER II. the essential requisites of a good house-filter ? What is necessary that every house-filter may be safe for use ? Are any filters absolutely germ- proof? How are the color, transparency, and odor of water determined, and what is the standard of comparison ? Is a turbid or colored water necessarily harmful, and may a perfectly -clear water be dangerous to use ? How are the total solids of a water determined quantitatively ? Describe the permanganate-of-potash test for the determination of the organic matter in water. What does an excess of chlorine or chlorides in water generally indicate, and why ? How may these be determined quantitatively ? If sewage contamination of a water be suspected, how may the suspicion be confirmed ? Why should the presence of nitrites or nitrates in water excite the suspicion of sewage contamination ? Give a test for each. By what reagent is the presence of ammonia determined ? How may the presence of lead, copper, zinc, or arsenic be detected? How may we know whether an excess of chlorides is due to sewage contamination or not? What is the probable source of ammonia if in excess and in company with nitrates, etc. ? Which is supposed to in- dicate the most recent contamination, nitrites or nitrates ? May nitrates arise from vegetable matters rather than animal ? What does the pres- ence of nitrates without nitrites or ammonia indicate ? What lime-salt is most readily removed by boiling ? What relation has the organic matter to the nitric acid ? Why is it not easy to make a biological or bacteriological examination of water? Into what four classes may water be divided ? Name some of the characteristics of these different classes. CHAPTER III. FOOD. IN order to preserve health and vigor it is necessary for animal beings to consume at intervals a sufficient quantity of substances known as foods. Alimentary substances, .or foods, may, therefore, be briefly defined as materials which, taken into the body and assimilated, sustain the processes of life, promote growth, or prevent destruction of the organized constituents of the body. QUANTITY AND CHARACTER OF FOOD NECESSARY. It has long been known, as the result of the empirical observation of feeding large bodies of people, that the various proximate principles composing the tissues must be combined in certain definite proportions in the food in order to preserve the normal degree of health and vigor of the body. Within a comparatively recent period physiologists have made experi- ments upon animals and human beings which have led to the same conclusions, and have enabled these proportions to. be fixed with more or less exactness. Considering man as an omnivorous animal, it may be laid down as an invariable rule that the following four alimentary principles are necessary to his existence. 1 Neither of these principles can be dispensed with for a prolonged period without illness or death resulting. 1. Water. This must be supplied in sufficient quantity to permit the interchange of tissue to be carried on in the body. 2. /Salts. Inorganic compounds of various kinds are 1 Physiologic, Landois, 2te Aufl., p. 448. .(87) 88 TEXT-BOOK OF HYGIENE. necessary to the preservation and proper construction of the tissues. They are all found in sufficient quantities in the various alimentary substances consumed by man and the lower animals. A deficiency of inorganic constituents in the food is followed by disease. 3. Proteids. Organic nitrogenous material, either animal or vegetable, is a necessary constituent of the food of man. Continued existence is impossible without a sufficient supply of nitrogenous substances. 4. Fats or Carbohydrates. The organic non-nitrogenous or carbonaceous principles of food are also necessary to the continuance of health. They are supplied either by fats or by carbohydrates (sugar, starch, etc.), which may, within certain limits, be used as substitutes for each other. Voit has shown that 17 parts by weight, of starch, is equivalent as carbonaceous or oxidizable food to 10 parts of fat. The physiology of nutrition has been very carefully studied by a large number of experimental physiologists, who have arrived at conclusions differing widely from those generally accepted twenty-five years ago. The division of foods into plastic and respiratory foods, or, in a general way, into proteids or muscle-builders, and fats and carbohydrates, or oxidizing foods, is now no longer recognized in science. It has been established that proteid tissues are not alone the result of proteid food, and that the accumulation of fat in the body is not altogether due to the excessive consumption of fats and carbohydrates. It has been further shown, contrary to the general belief, that the nitrogenous or proteid tissues are not used up during hard labor any faster than when at perfect rest, but that, on the contrary, increased muscular exertion is attended by increased consump- tion of stored-up fat. These facts have led to a modification of the standard dietaries formerly employed. At present the standards of the quantity of food principles required to maintain equality between bodily income and expenditure are those calculated by Professor QUANTITY AND CHARACTER OF FOOD NECESSARY. 89 Voit, after many experiments upon human beings and the lower animals. These standards are as follow : TABLE VII. ADULT MALE OP AVERAGE WEIGHT. At Rest. Moderate Labor. Severe Labor. Proteids .... Fats 110 grammes 50 " 118 grammes 50 " 145 grammes 100 " Carbohydrates . . 450 " 500 " 500 " As the average weight of women is less than that of men, a reduction of from 15 to 20 per cent, in the various food prin- ciples may be made for the female ration. The relative proportion of nitrogenous to non-nitrogenous principles in this ration is about 1 to 5. Tn the older diet standards, e.g.^ Moleschott's, the proportion of nitrogenous to non-nitrogenous principles is much larger, being, for a man at moderate labor, proteids, 130 grammes; fats, 84 grammes; and carbohydrates, 404 grammes, or about 1 to 3.75. While from ignorance, or motives of economy, many men sustain life and preserve health at hard labor on rations varying considerably from the standard above given, it is probable that, all things being considered, the most perfect physiological ration would also be the most economical. Thus, Professor Vaughan proposes a daily ration consisting of bread, cod-fish, lard, potatoes, bacon, beans, milk, sugar, and tea in such proportions as to fur- nish 123 grammes proteids, 70 grammes fats, and 550 grammes carbo-hydrates. The total cost or money value of this ration at present prices is about thirteen cents. In actual food value it is not inferior to the daily fare of the habitue of Delmonico's. The above standard diet-tables give the relative proportions of food principles in terms of their proximate chemical composi- tion. In practice it is very necessary to choose such food ma- terials as will represent approximately the proximate principles 90 TEXT-BOOK OF HYGIENE. required. The following tables give the approximate value in proteids, fats, carbohydrates, and salts of a number of articles used as food: TABLE VIII. ANIMAL FOODS. ARTICLES. Water (per cent.). Proteids * (per cent.). Fats (per cent.). Non-nitrogenous Matters (per cent.). Ash (percent.). Proportion of Nitrogenous to Non-nitrogenous Matters. Moderately fat beef .... 72.25 21.39 5.19 1.17 1: 0.4 Ox-heart (fat animal) .... Fat veal 70.08 72.31 21.51 18.88 7.47 7.41 0.16 007 0.78 1 33 1: 0.6 1: 0.7 Moderately fat mutton . . . Lean pork 75.99 72 57 18.11 19 91 5.77 6 81 1 ^^ I. oo 1 10 1: 0.6 1- 06 Salt ham 62.58 22.32 8 68 6.42 1: 0.7 74 16 23.34 1 13 19 1 18 1: 01 Venison 75 76 19.77 1 92 1 42 1.13 1: 02 Horse-flesh 7427 21.71 2 55 46 1 01 1: 0.2 Liver-sausage . . ... 48 70 15 93 26 33 6 38 2 66 1: 3.3 Beef-extract 21 70 60 79 17 51 Chicken (lean) 76.22 19.72 1.42 127 1.37 1: 0.2 Pigeon 75.10 22.14 1 00 076 1.00 1: 0.1 Wild duck 70 82 22 65 3 11 2 33 1 09 1- 03 Haddock . . ... 80.92 17 09 035 1 64 1: 00 80 71 10.11 7 11 207 1: 00 75 49 22.23 047 1.71 1- 00 Mackerel 68.27 23.42 6.76 1.85 1: 0.5 Conger-eel 79.91 13.57 5.02 039 1.11 1: 0.7 Salmon 76 38 13 10 4 57 4 67 1 28 1- 10 Carp 76.97 20.61 1.09 1.33 1: 01 Pike . 77.45 20.11 69 092 083 1: 0.1 Sole 86.14 11.94 25 045 1 22 1: 0.1 89.69 4.95 37 2 62 2 37 1: 0.7 Caviar Beef-liver 45.05 72.02 31.90 19.59 14.14 5 60 1 10 8.91 1 69 1: 0.8 1: 0.5 Calf's brains 74.14 (8 albumen) 13 14 1 70.00 27.00 035 11 65 1 Fat of pork (salt) 9 15 9 72 75 75 5 38 1- 13 6 Hen's esrff . ... 73.67 12.55 12.11 055 1.12 1: 1.7 White of egg 85.75 12.67 0.25 0.59 1: 0.1 Yelk of egg 50.82 16.24 31.75 0.13 1.09 1: 3.4 Cow's milk 87.41 3.31 3.66 4.92 0.70 1: 3.4 Human milk 87.09 2.48 3 90 6.04 0.49 1: 5.2 Cream 66.41 3.70 25.72 3.54 0.63 1: 13.1 Rich cheese 35.75 27.16 30.43 2.53 4.13 1: 2.1 Lean cheese 48.02 32.65 8.41 6.80 4.12 1: 0.7 Butter 14.14 0.86 83.11 0.70 1.19 1: 169.9 Whey 93.31 0.82 0.24 4.98 0.65 1: 6.6 Kuinys 87.88 2.83 0.94 7.08 1.07 1: 3.1 Condensed milk. . . . 30.34 16.07 12.10 38 88 2 2 61 1: 37 Containing 16 per cent, nitrogen. a Containing 22.26 per cent, cane-sugar. QUANTITY AND CHARACTER OF FOOD NECESSARY. 91 TABLE IX. VEGETABLE FOODS. ARTICLES. Water (per cent.). Proteids (percent.). Fats (per cent.). Sugar (per cent.). Other Non-nitro- genous Mat- ters (per cent.). Woody Fibre (per cent.). Ash (per cent.). Proportion of Nitrogenous to N o n - n itroge- nous Matters. Wheat 13 56 1242 1 70 1 44 66 45 2 66 1 77 1 57 Spelt. 1209 11.02 2.77 6644 5 47 2 21 1 65 Rye 15 26 11.43 1.71 096 66 86 2 01 1 77 1 62 Barley 13.78 11.16 2.12 65 51 480 2 63 1 62 Oats . 12 92 11.73 604 222 53 21 1083 3 05 1 56 1388 10.05 476 4.59 62 19 2 84 1 69 1 75 Hulled rice 1323 7 81 069 76 40 78 1 09 1 99 Millet 11.26 11.29 3.56 1.18 66 15 4.25 2 31 1 65 Buckwheat 11 36 10 58 2 79 55 84 16 52 2 91 1 57 Beans 14.84 23.66 1.63 49 25 7.47 3.15 1 22 1431 22.63 1.72 53 25 5.45 2 65 1 25 12 51 24.81 1.85 5478 3.58 247 1 28 Wheat-flour 1486 8 91 1 11 2.32 71 86 0.33 61 1 85 Rye-flour 14.42 10.97 1.95 3.88 65.86 1.62 1.48 1 6.7 Barley-flour 15 06 11 75 1 71 3.10 67 80 11 047 1 63 Buckwheat-flour .... 14.27 1046 928 15 50 1.89 6.11 1.06 2.25 71.40 61.42 0.89 2.24 1.21 2.02 1 8.2 1 4.8 Cornmea^ 1400 11 10 8 10 65 10 1 70 1 67 Starch 14.84 1.46 83.31 0.39 1 57.1 Macaroni . . .... 13.07 9.02 0.28 76.79 0.84 1 8.6 Fine wheat-bread. . . . Fresh rye-bread .... English biscuit 38.51 4402 7.45 6.82 6.02 7.18 0.77 0.48 9.28 2.37 2.54 17.02 49.97 45.33 58.08 0.38 0.30 0.16 1.18 1.31 0.83 1 7.9 1 8.1 1 12.7 75.77 1.79 0.16 20.56 0.75 0.57 1 11.6 Beet (red) 87.88 1.07 0.11 6.55 2.43 1.02 0.94 1 8.6 Sugar-beet .... 83.91 2.08 0.11 9.31 2.41 1.14 1.04 1 5.7 9051 1.40 4.68 2.14 1.27 1 5.8 Carrot (large) 8705 1.04 0.21 6.74 2.66" 1.40 0.90 1 9.4 88.32 1.04 0.21 1.60 7.17 0.95 0.71 1 8.8 Turnip 91.24 0.96 0.16 4.08 1.90 0.91 0.75 1 6.5 Radish 86.92 2.92 0.11 1.53 6.90 1.55 1.07 1 4.5 Horseradish. 76.72 2.73 0.35 15.89 2.78 1.53 1 6.0 85.01 2.95 0.22 0.40 8.45 1.76 1.21 1 3.1 Onion 70 18 2.68 0.10 5.78 19.91 0.81 0.54 1 9.6 87.62 2.83 0.29 0.44 6.09 1.49 1.24 1 2.5 Garlic 64.66 6.76 0.06 26.31 0.77 1.44 1 3.9 95.60 1.02 0.09 0.95 1.33 0.62 0.39 1 2.4 95.21 1.06 0.61 0.27 1.15 1.07 0.63 1 2.4 Pumpkin 90.01 0.71 0.05 1.36 5.87 1.36 0.64 1 10.2 92.87 1.25 0.33 2.53 1.55 0.84 0.63 1 3.6 93.32 1.98 0.28 0.40 2.34 1.14 0.54 1 1.6 80.49 5.75 0.50 10.86 1.60 0.80 1 2.0 Snap beans 86.10 4.67 0.30 6.60 1.69 0.64 1 1.5 Cauliflower 90.39 2.53 0.38 1.27 3.74 0.87 0.82 1 2.2 Winter cabbage 80.03 3.99 0.90 1.21 10.42 1.88 1.57 1 3.3 Savoy cabbage .... 87.09 3.31 0.71 1.29 4.73 1.23 1.64 1 2.2 Red cabbage .... 85.63 4.83 0.46 6.22 1.57 1.29 1 1.5 Spinach 90.26 3.15 0.54 0.08 3.26 0.77 1.94 1 1.3 Lettuce . .... 94.33 1.41 0.31 2.19 0.73 1.03 1 1.9 TEXT-BOOK OF HYGIENE. TABLE IX. (continued). VEGETABLE FOODS. ARTICLES. "Water (per cent.). Proteids (per cent.). Fats (per cent.). Sugar (per cent.). Other Non-nitro- genous Mat- ters (per cent.). Woody Fibre (per cent.). Ash (per cent.). Proportion of Nitrogenous to N o n - n itroge- nous Matters. Mushrooms (fresh) . . . " (dried) . . . Truffle 91.11 17.54 7280 2.57 23.84 891 0.13 1.21 062 1.05 9.59 3.71 34.56 754 0.67 6.21 7 92 0.76 7.05 2 21 1: 1.9 1 : 1.9 1-10 Apples 1 83.58 0.39 7.73 5 17 1.98 0.31 1 : 35 2 83 03 0.36 826 3.54 430 0.31 1 :33 3 8486 040 3.56 4.68 4 34 0.66 1 : 24 3 8003 0.65 448 7.17 6.06 0.69 1 19 3 81.22 049 469 6.35 5.27 0.82 1 :249 Cherries 80.26 0.62 10.24 1 17 6.07 0.73 1 :19 9 78 17 059 14 36 1 96 360 053 1-290 87.66 1.07 0.45 6.28 0.48 2.32 0.81 1:78 86 21 0.53 3.95 1.54 5.90 049 1 :13 Blackberries 8641 051 4.44 1 76 5 21 048 1 : 145 84.71 0.36 9.19 2 31 0.91 0.66 1 :37 1 Whortleberries 78.36 0.78 5.02 0.87 1229 1.02 1:97 85.74 0.47 7.03 1.40 352 0.42 1 :21 Currants . 84.77 0.51 6.38 090 457 0.72* 1 : 18 5 Dried apples 32.42 1.06 41 61 14.68 5 59 1.96 1 :55 6 pears 29.41 2.07 0.35 29.13 29.67 686 1.67 1 :29.1 prunes cherries 29.83 49.88 255 2.07 0.53 030 42.65 31.22 18.85 14.29 1.43 0.61 2 1.39 1.63 1 :25.5 1 :22 2 32.02 2.42 0.59 54.56 7.48 1.72 1.21 1 :260 fics . 32.21 5.06 45.28 2.96 1:89 Sweet almonds .'.... 5.39 24.18 5368 7.23 6.56 2.96 1:42 Walnut 4.68 16 37 62.86 7.89 6.17 2 03 1:72 Hazel-nut ; . Chestnuts (fresh) . .* . Peanut. t 3.77 51.48 G.50 15.62 548 28.20 66.47 1.37 46.40 9.03 38.34 15.70 3.28 1.61 1.83 1.72 3.20 1 : 8.0 1 : 7.5 1 : 2.3 In addition to maintaining a proper proportion between the various alimentary principles, it is necessary to vary the articles of food themselves, otherwise they are liable to prove nauseating. The necessity of variety in the food, in order to preserve the appetite, is familiar to every one. By keeping the proportions of the above table in view it will be seen at once that if a man wished to live on beef alone he would be obliged to eat about 2 kilogrammes per day in order to get a sufficient amount of non-nitrogenous food. Of 1 Those green fruits all contain in addition from .2 to 2.1 per cent, of free acid. ' Without stones. QUANTITY AND CHARACTER OF FOOD NECESSARY. 93 potatoes, in order to get enough nitrogenous food, he would have to eat daily 8 kilogrammes. No human stomach could prove equal to the task of digesting this excess of material. On the other hand, it is to be noted how perfect the combination of the /various principles is in human milk. In cows' milk, which is nearest in composition to human milk, the non-nitrogenous principles are deficient. Hence, the important practical point that when ordering milk diet for a patient a small portion of carbonaceous food (bread, rice, or sugar) must be added if the standard of health shall be reached or maintained. Climate has probably very little influence upon the amount of food required by the individual. The actual quantity of food consumed varies little between various races or in different parts of the earth. It is true, however, that a larger proportion of fat is required in cold climates. That fatty articles of food readily undergo oxidation and furnish a large amount of animal heat is proven both by observation and experiment. The albuminoid proximate principles of the food, proteids, are represented by the nitrogenous constituents of organic tissues. These are the vitellin and albumin of eggs, albumin, fibrin, globulin, myosin, syntonin, and other nitrogenized prin- ciples of flesh and blood ; the casein of milk, the gluten, fibrin, and legumin of cereal and leguminous seeds and plants, gelatin, and chondrin. Fat constitutes an integral component of animal tissue, and is found in abundance as a constituent of nerve-tissue, marrow, and subcutaneous connective tissue. In food it is represented especially in the fatty tissue of meat, the yelk of eggs, butter, etc. The carbohydrates are represented especially by various products of the vegetable world, as sugar, starch, dextrin, etc. Water and the various other inorganic proximate princi- ples, chief among which are compounds of calcium, sodium, and potassium, are usually found in sufficient proportion in the other alimentary substances. 94 TEXT-BOOK OF HYGIENE. The food should be taken in appropriate quantities and properly prepared. A larger quantity than necessary may over- tax the digestive organs and thus yield less than the required amount of nutritive material to the body. Physical exertion increases the consumption of fatty prin- ciples. Hence, as in the cases of the athlete or prize-fighter in training, larger quantities of these principles are required to keep the nutrition of the body at the standard of health. During mental work, however, less carbohydrate material is consumed than during physical labor. The greater consumption of carbohydrates during muscular exercise is shown by the following table, which gives the amounts of carbon dioxide and nitrogen excreted by a man at rest and during labor : TABLE X. CO, Excreted. Nitrogen Excreted. At rest 912 grammes 36.3 grammes. At work 1284 " 36.3 " In youth the processes of combustion (production of carbon dioxide) go on with greater rapidity than after adult life is reached. For this reason young persons rarely get fat, the fat- producing food being burnt up in the body by the greater meta- bolic activity of the young cell. Hence, fats and carbohydrates should form a larger relative proportion in the diet of the young than in that of grown persons. Low external temperature causes a greater and more rapid consumption of fat than high external temperature. During febrile conditions, however, the destruction of stored-up fat in the body the wasting away is one of the most notable phenomena ; hence the importance of supplying fat and fat-producing food in chronic febrile diseases. "Der Mensch ist was er isat" said Ludwig Feuerbach. 1 1 Gottheit, Freiheit und Unsterblichkeit von Standpunkt der Anthropologie, p. 5. CLASSIFICATION OF FOODS. 95 The pungency of the epigram is somewhat lost in the transla- tion, which is, literally, "Man is what he eats" The intimate relations of mental, moral, and physical conditions of health to the quality and quantity of food deserve the earnest attention of the educated physician and sanitarian. CLASSIFICATION OF FOODS. Foods and victuals are generally divided into foods proper and so-called >accessory aliment. The classification is not exact, however, as the latter, which are commonly regarded as articles of luxury, may under certain circumstances become necessities, and hence should not be considered as forming a separate class. Foods are either of animal or vegetable origin. Those de- rived from animal sources are milk, the flesh of animals, birds, reptiles, and fish, and the eggs of the three last named. The foods derived from the vegetable kingdom comprise the seeds of various plants (cereals, legumes), roots, herbs, ripe fruits, the fleshy envelopes of various seeds (which may prop- erly be classed with the fruits), and various fungi. There are also in common use a number of beverages, e.gr., water, alcoholic liquors, alkaloidal infusions (tea, coffee, cocoa), etc. In addition, a number of substances or compounds are in common use as condiments. Their function is either to render victuals more palatable, or to promote digestion and assimilation. Vinegar, mustard, and common salt are familiar examples. FOODS OF ANIMAL ORIGIN. Milk. Human milk is, so far as known, the one perfect food for man found in nature. It contains, in proper proportion, representatives of all the different classes of proximate principles necessary to nutrition. One hundred parts contain about 2.5 parts of proteids (casein and albumin) ; 3.9 parts of fat (butter) ; 6.0 parts of sugar, and .5 of salts. The reaction of human milk is slightly alkaline ; that of fresh cows' milk is neutral. 96 TEXT-BOOK OF HYGIENE. In human milk there are 12.9 parts of solid matter to 87.1 of water, while in cows' milk the proportions are: Proteids, 4.0 per cent. ; fats, 3.4 per cent ; sugar, 3.8 per cent. ; salts, 0.6 per cent., or 11.8 total solids and 88.2 water. 1 Of the solids in milk, cows' milk contains more proteids, while human milk is richer in fats and sugar. Hence, in using cows' milk as a substitute for human milk the proteids are di- luted by the addition of water, and the non-nitrogenous com- ponents increased by adding sugar and, under some circum- stances, fat (cream). Goats' and asses' milk are sometimes used as substitutes for human milk, but they do not approach much nearer in com- position to the latter than does cows' milk. On standing, the fatty constituent of milk, the cream, sepa- rates, and on account of its less specific gravity rises to the surface, where it forms a layer of varying thickness. After standing a longer interval the milk undergoes certain physical and chemical changes. Lactic acid is formed at the expense of part of the sugar of milk (a sort of fermentation taking place), and, acting upon the casein, produces coagulation. This is the so-called "bonny-clabber." When the fermentation continues, especially under a slightly elevated temperature, the solid portion becomes condensed (curd), and a sweetish-acid, amber-colored liquid, the whey, separates. The curd, after further fermentation, under appropriate treatment, becomes converted into cheese. Whey is sometimes used alone or mixed with wine as an article of diet for the sick. Butter is made from the cream by prolonged agitation in a churn. The fat-globules adhere to each other and form a soft, unctuous mass, of a yellowish color, solid at ordinary tem- peratures. After the butter is all removed in this way the balance of the cream remains in the churn as buttermilk. This is an article of considerable nutritive value, although its excess 1 Average of a number of analyses. FOODS OF ANIMAL ORIGIN. 97 of acid renders it unsuitable as an article of diet in man) cases. The specific gravity of fresh milk should not be below 1030. It should, however, be borne in mind that the richest milk is not always that which has the highest specific gravity. In fact, a sample of rich milk, containing a large proportion of cream, may show, when tested with the lactometer, a lower specific gravity than a specimen of much poorer milk. Hence, the lactometer, although a useful instrument in guarding against excessive dilution of the milk with water, is not a very trust- worthy guide in determining the quality of the milk. Objections are often urged against the use of so-called " skim-milk," i.e., milk from which the cream has been removed. In some cities in this country the police, or representatives of the sanitary authorities, seize and confiscate all skim-milk found in possession of dealers. There appears to be no rational basis' for the opinion held by many that skim-milk is not a proper and useful article of food. Before the lactic-acid fermentation has taken place it differs from fresh milk merely in the fatty and other matters removed in the cream. It contains nearly all of the proteids, sugar, and salts of whole milk, and may be used as an article of food with great advantage and entire safety. In certain diseased states it is of exceptional value as an article of diet. The sole objection of any weight to skim-milk is that it may be at times sold fraudulently as fresh milk. This is, how- ever, a question of little sanitary interest, but one principally of commercial ethics. Milk is frequently adulterated by the addition of water. More deleterious substances are rarely found. An excess of water gives the milk a bluish tinge and reduces its specific gravity. The addition of water may become especially dangerous by introducing the virus of some of the acute infectious diseases. Thus, the localized epidemics of typhoid and scarlet fevers have, in quite a number of instances, been traced to mixing the milk with water containing the poison of these diseases. It should, 98 TEXT-BOOK OF HYGIENE. however, be stated that milk which contains the virus of typhoid fever has not necessarily been adulterated by the addition of water. The poison may have been introduced with the water used in washing the can, and adhered to the sides of the latter. In filling the can with milk a good culture medium is supplied in which the typhoid bacillus flourishes. It has long been a mooted question whether acute or chronic infectious diseases of the milk-giving animal may be communi- cated to persons using the milk of such animals. While there is little positive knowledge upon the subject, it would seem prudent to avoid the use of milk from diseased animals, if pos- sible, or to destroy any organic virus the milk may contain by previously boiling the milk. After thorough boiling little fear need be entertained of communicating either acute or chronic infectious diseases through this medium. Demme and Uffel- mann have reported cases which seem to demonstrate the pos- sibility of tuberculous infection through the medium of the milk. Professor Bang, of Copenhagen, has recently made a series of experiments and observations which has led him to the con- clusion that the milk of tuberculous cows and tuberculous women, in which there are no lesions in the mammary gland, only exceptionally contains the contagium. Professor Bang at the same time, however, points out that the milk from tubercu- lous udders is extremely dangerous, and that the tubercle bacilli are to be found not only in the milk itself, but in the cream, buttermilk, and butter made from it; and that such milk is sometimes infective by ingestion, even after exposure to 65 C. of heat, and by injection into the peritoneal cavity after exposure to 80 C. The infectiousness of the milk of cows suffering from splenic fever (milzbrand, anthrax) has been proven by Bollinger and Feser. Anthrax bacilli have been found in such milk by Chambrelent and Moussons. The agency of milk in the spread of scarlet fever is well recognized, but the manner in which the contagium gained FOODS OF ANIMAL ORIGIN. 99 access to the milk was not well understood. Recently, however, an incident happened in England which seems to prove a close connection between this widespread and fatal disease and a dis- order in the milk cattle. The evidence in support of this view is as follows : Mr. W. H. Power, of the English Local Government Board, was detailed to investigate certain outbreaks of scarlet fever which seemed to have especial relation to the milk-supply from a particular dairy-farm. Upon inspection this dairy was found to be in excellent sanitary condition as regards cleanliness, water-supply, sewerage, etc., and for a time considerable difficulty was experienced in locating the cause of the outbreaks. Im- probable as it may at first sight appear, it seems to have been incontestably established that the epidemics of scarlatina were due to the use of milk obtained from cows attacked by a peculiar disease manifested by a vesicular eruption followed by ulceration of the udder. The chain of circumstances connecting the dis- ease in the cows with the outbreaks of scarlet fever in certain districts in London, supplied with milk from the diseased cows, was so strongly forged by the able investigator, into whose hands the work had been committed by the authorities, that hardly a doubt can exist that the one disease owed. its origin to the other. The pathological evidence furnished by Dr. Klein lends strong support to the view that the Hendon cow disease and scarlet fever are intimately related to each other. A bacterial organism was found in the material from the ulcerated udders of the sick cows, which presents similar characters to a micro- coccus found by the same observer in the blood of scarlet-fever patients. These results require more extended investigations before they can be unreservedly accepted. The milk of cows fed upon the refuse of breweries and dis- tilleries " swill-milk " is believed by many physicians to be unwholesome. If so, it is, probably, only by reason of the un- favorable hygienic conditions under which the animals are kept. If the stables are clean, dry, and well ventilated, and the ani- mals receive plenty of fresh air and exercise, swill-fed cows 100 TEXT-BOOK OF HYGIENE. should produce as nutritious milk as when they are fed upon different food. Much of the present agitation against "swill- milk" is more prompted by political demagogism than by scientific knowledge. The milk of animals suffering from certain diseases is often dangerous to health. In some of the Western and Southern United States, cows are not infrequently attacked by an acute febrile disease called " the trembles," from one of the prominent symptoms. The milk of cows suffering from this disease pro- duces severe gastro-iritestinal disorder, collapse, fever, etc., in the consumer. This disease, called "milk-sickness," is fatal in a pretty large proportion of cases. It is said that the flesh of animals with "the trembles" will, if eaten, produce similar dan- gerous effects. A late writer (Dr. Beach, of Ohio) estimates that 25 per cent, of the Western pioneers and their families died of this disease. For the ready determination of the quality of milk, instru- ments known as lactoscopes, lactometers, and creamometers are used. The lactoscope indicates the opacity of the milk, upon which the proportion of cream depends. One convenient mod- ification of the lactoscope is the little instrument termed the pioscope. This consists of a disk about 6| centimetres in diam- eter, with a slight depression in the centre. A little milk is placed in the depression and covered with a glass disk, clear in the centre and opaque around the border, which is divided into six divisions of different shades, varying from white to dark gray. The quality of the milk is marked upon the division whose color corresponds with that of the milk in the centre. A better, but still not very accurate, indicator of the quality of the milk is the creamometer. This consists of a cylindrical glass vessel with the upper half divided up into hundredths. The glass is filled up to the zero mark with milk, and allowed to stand until all the cream has separated. The thickness of this layer is then read off on the scale. In Chevallier's instru- FOODS OP ANIMAL ORIGIN. 101 ment, 10 per cent, of cream is the minimum proportion that should be furnished by the milk. The specific gravity, which is a fair guide to the quality of the milk, with the reservations above mentioned, is measured by means of the lactometer or lactodensimeter. The specific gravity of good cows' milk should not be less than 1029. In order to prevent the rapid fermentation of milk various methods of preservation have been adopted. The addition of alkalies, or antiseptics, retards the lactic-acid fermentation, while the abstraction of a portion of the water and addition of sugar (condensed milk) preserves it for an indefinite time. The mere addition of water restores it to nearly its original condition. Tyrotoxicon in Milk. This substance, first found in poison- ous cheese, and later in milk, ice- cream, custards, etc., is believed by Professor Vaughan to be the cause of true cholera infantum, and many of the clinical phe- nomena of this disease lend strong support to such a* view. The conditions under which the poison is developed have not yet been sufficiently studied to enable correct conclusions to be drawn. Butter. Butter is of especial value as food on account of the large amount of easily digestible fat which it contains. It is almost always used as accessory to other articles of food, to ren- der them more palatable. When pure and fresh, it is one of the most delicious of creature comforts. It soon undergoes the butyric-acid fermentation, however, becoming " rancid," as it is termed, when it is unfit for food. The great demand for butter and its consequent high price FIG. 3. CHEVALLIKR'S CREAMOMETER. 102 TEXT-BOOK OF HYGIENE. have led to its extensive sophistication. Butter is now very largely substituted by an artificial product termed oleo-margarine, or butterine. This artificial butter is made from beef-suet by the following process : Fresh beef-fat is melted at as low a temperature as possible, never higher than 52 to 53 C. [126 to 128 F.]. All membrane and tissue are then removed, and the resulting clear fat is put into presses, where the stearine is extracted. The liquid fat, free from tissue, and with nearly all its stearine removed, is known as "oleo-margarine oil." The next step in the process is " churning." The oil is allowed to run into churns containing milk and a small quantity of coloring material (annatto), where, by means of rapidly-revolving pad- dles, it is churned for about an hour. When this part of the process is complete, the substance is drawn off from the bottom of the churn into cracked ice. When cool it is taken from the ice, mixed with a proper quantity of salt, and is then worked like butter and put into firkins for the market. It is also molded into attractive prints in imitation of dairy-butter. 1 When the materials from which oleo-margarine is made are sweet and clean, and when the process of manufacture is prop- erly conducted, the resulting product is an entirely harmless article, and probably differs very little in nutritive value from butter itself. Cheese. The value of cheese as a food depends upon the large amount of proteids and fat which it contains. The rich varieties of cheese, such as Fromage de Brie and Roquefort, con- tain on an average 35 per cent, of fat and 27 per cent, of proteid compounds. Parmesan contains only about 18 per cent, of fat and nearly 40 per cent, of proteids, while Edam and Cheshire cheese, which may be considered as standing about midway between the above, contain 30 per cent, of fat and nearly 28 per cent, of proteids. From these figures it appears that cheese is one of the most nutritious aliments obtainable, but it cannot 1 Dr. W. K. Newton, Fifth Annual Report of the State Board of Health of New Jersey, 1881, p. 107. FOODS OF ANIMAL ORIGIN. 103 be eaten in large quantities at a time, as it is exceedingly liable to cause disturbances of the digestive organs. The constipating property of cheese is well known to the public. The relative value of different kinds of cheese in alimentary principles is given in the following table: TABLE XL KIND OF CHEESE. Proteids (per cent.). Fats (per cent.). Sugar (per cent.). Salts (percent.). Cheshire 27.68 27.46 5.89 5.01 Edam 24.07 30.26 4.48 4.91 29.48 26.71 2.27 4 62 27.69 33.44 3.15 5.35 Neufchatel 17.44 40.80 5.21 2.05 Parmesan 41.19 19.52 1.18 6.31 Cheese is not often adulterated. The only articles used with success in its sophistication are lard and oleo-margarine, which are incorporated with the casein during the process of manufacture. It sometimes undergoes chemical changes which render it intensely poisonous when eaten. Prof. V. C. Vaughan, of the University of Michigan, has ascertained that the substance causing the poisonous symptoms is a chemical compound termed by him tyrotoxicon. This same poison has also been found by Professor Vaughan and other chemists in ice-cream and fresh milk, which produced poisonous symptoms when consumed. The poison is supposed to be a ptomaine produced by the agency of a micro-organism, which has, however, not yet been isolated. Meat. The flesh of mammals, reptiles, birds, fish, and invertebrate animals is used as food by man. Falck 1 has classi- fied the varieties of animals which furnish food to the inhabitants of Europe. There are 47 varieties of the mammalian class, 105 of birds, 7 of amphibia, 110 of fish, and 58 of invertebrates. 1 Das Fleisch, Gemeinversteendliches Handbuch der Wissenschaf tlichen und Praktischen Fleisclikunde. 104 TEXT-BOOK OF HYGIENE. Meat is the most important source of proteids in the food. In the more commonly used varieties of meat the proteids and fats constitute from 25 to 50 per cent, of the entire bulk, the proportion depending largely upon the age of the animal and its bodily condition. The following table shows the influence of these two factors upon the relative proportions of the fats and proteids contained in the meat: TABLE XII. 1 Proteids (percent.). Fats (per cent.). Moderately fat beef 21.39 5.19 Lean beef 20.54 1.78 Veal 10.88 7.41 Verv T fat mutton 14.80 36.39 / Fat pork 14.54 37.34 Lean pork 19.91 6.81 Hare 23.34 1.13 Lean chicken 19.72 1.42 The flesh of animals, which is neutral in reaction immedi- ately after death, soon becomes acid in consequence of the formation of lactic acid. The acid, acting upon the sarcolemma and the muscular fibre, renders it softer and more easily per- meable by fluids when cooking, and more susceptible to the action of the gastric juice when the meat is taken into the stomach. Certain kinds of meat mutton and venison, for example are often kept so long before being eaten that a considerable degree of putrefaction has taken place when they are brought upon the table. The wisdom of this practice is questionable from a hygienic point of view. Meat is sometimes eaten raw, but it is usually first cooked. The methods of cooking in general use are boiling, frying, roasting, broiling, and baking. By either of these methods of 'Abridged from Loebisch ; article "Fleisch" in Realencyclopjedie d. ges. Heilkunde, vol. v, p. 340. Fuller details will be found in Table VIII. FOODS OF ANIMAL ORIGIN. 105 cooking, when properly carried out, the nutritious properties of the meat are preserved, and it is rendered digestible. The culinary art deserves the closest attention of students of hygiene. A number of soluble preparations of meat (beef-extract, beef-essence, beef-juice) are found in the market, and highly recommended as containing all the nutritious qualities of the meat from which they are prepared. These, and similar products of domestic preparation (broths and teas), contain in reality very little nutritive material, but are of use almost solely as stimulants to the appetite and digestion. They have a place in the dietary of the sick, but their nutritive value is small. On the other hand, a number of partly or wholly predi- gested (peptonized or pancreatized) preparations of meat are offered for sale, many of which have a high nutritive value. They cannot, however, be used as articles of diet except for a short time, or as a temporary succedaneum for meat in diseases attended with weakness or derangement of the digestive organs. Meat may be unfit for food from various causes. Thus the flesh of animals dying from certain diseases splenic fever, pleuro- pneumonia, tuberculosis in its advanced stages, cow- or sheep- pox should not be used as food when it can be avoided. Cases are on record proving the poisonous character of meat from animals which suffered, at the time of death, from some of the above-mentioned diseases. The most important condition to be borne in mind is that certain parasites (trichina spiralis, echinococcus, cysticercus), which frequently infest the flesh of animals, especially hogs, not infrequently give rise to serious or even fatal diseases in persons consuming such meat. Any meat containing these parasites, or suspected of containing them, should therefore not be used as food unless precautions be first taken to destroy the life of the parasite. Of the parasites mentioned the trichina spiralis is the most important in this connection, as it frequently occurs in the flesh of hogs, rats, dogs, cats, and other carnivorous animals. Rats are said to be infested with the parasite more frequently than 106 TEXT-BOOK OF HYGIENE. any other animals. The trichinae are found in two forms, one, the mature form, inhabiting the intestinal canal. The immature form, or muscle trichinae, are found in striped muscle, coiled into spirals and encysted in a fibrous capsule. They gain access to their host in the following manner: Flesh containing living trichinae is taken into the stomach, where the muscular tissue and the fibrous envelope are dissolved, and the inclosed worms set free. These mature in the intestinal canal, where sexual reproduction takes place, and the young embryos pass through the intestinal walls and other tissues until they become imbedded in striated muscle. Localized epidemics of trichinosis have been reported in this country and Europe, and in nearly every instance the source of the disease has been traced to the inges- tion of uncooked pork. Meat known to be trichinous should not be used unless in times of great scarcity. It may, however, be rendered innocuous by thorough cooking. . A temperature of 60 to 70 (140 to 160 F.) destroys the life of the parasite and renders the meat safe. On account of the frequent occur- rence of trichinae in pork, this meat should never be eaten unless thoroughly cooked. It has been ascertained that salted and smoked pork is not free from danger, as the parasites are not killed in the process of curing the meat. Hence, ham and sausage should not be eaten raw, as the danger from these articles is almost equally as great as from fresh pork. Cysticercus cellulosa^ the transition form of one variety of tape-worm, and which is the parasite in measly pork, may also gain entrance to the human body, and, failing to undergo devel- opment, cause very serious lesions of various organs and tissues. The frequency of tape-worm is evidence that pork is often thus diseased. The use of partially decayed meat or fish has often been the cause of serious or fatal illness. Sometimes the illness par- takes of the character of septic infection. In these cases it is probable that the morbid process is due to the action of the organisms of putrefaction. In other cases the symptoms are FOODS OF ANIMAL ORIGIN. 107 widely different. These cases have been the source of much perplexity to physicians and toxicologists until very recently. Within the past six years, however, Selmi, Husemann, Brouardel, Casali, and others have drawn attention to certain intensely poisonous chemical compounds found in decomposing flesh, and which have been named by Selmi ptomaines. While there is still much uncertainty concerning the nature of these compounds, it seems pretty well established that when flesh undergoes de- composition, in the absence of oxygen, certain unstable chemical combinations are formed which act as violent poisons. Selmi, followed by most toxicologists, believes these compounds to be alkaloids, analogous to the vegetable alkaloids, such as morphine, atropine, etc. Casali, on the other hand, disagrees with this opinion, and believes the ptomaines to be amido compounds. Husemann regards Casali's hypothesis as plausible, inasmuch as the formation of amido compounds in animal and vegetable bodies during decomposition is well established. The form of poisoning due to the organisms of putrefaction is not infrequent. An extensive outbreak of this nature occurred at Andelfingen, in Switzerland, in 1839. A musical festival was held, at which there were over 700 present. Out of these 444 were suddenly attacked by violent gastro-enteric and nervous symptoms. Ten of the patients died. The illness was traced to roast veal, which had been kept in a warm place for two days after roasting, and which was probably in a state of partial decomposition. The class of cases which seem more probably due to the action of ptomaines or related poisons, have been frequently observed after eating sausages or canned meats. Sausage poi- soning is not rarely observed in Germany. It has been ascer- tained that the internal portions of the sausage are the most poisonous. It is supposed that the ptomaines, which are formed in the absence of oxygen, are the active agents in the pro- duction of the train of symptoms. Poisoning by canned meat seems to be due to a similar poison. 108 TEXT-BOOK OF HYGIENE. In July, 1885, an outbreak of disease, due to eating un- wholesome beef, was caused at Momence, Illinois. Chemical examination of specimens of the meat showed the presence of an alkaloidal body, which was believed to be a ptomaine, but its nature was not definitely determined. Fish, oysters, crabs, and lobsters frequently give rise to symptoms of poisoning. In most of these cases the poisoning is probably due to partial decomposition, but it is a well-known fact that oysters and crabs are unfit for food at certain seasons. Some persons, however, are subjects of a peculiar idiosyncrasy, in consequence of which shell-fish always produce certain un- pleasant symptoms, among which nettle-rash and a choleraic attack are most prominent. That form of fish-poisoning known among the Spaniards in the West Indies as siguatera is, however, very grave. The mortality is large, and in many cases death succeeds rapidly upon the attack. The symptoms are as follow: Sometimes suddenly, sometimes preceded by dizziness and indistinct vision, great prostration and paralysis occur. Often death follows the onset of the symptoms in two and three hours ; exceptionally in less than twenty minutes. In most cases consciousness is totally lost; in others it persists, with interruptions, until death. Sensa- tion and the powers of speech and deglutition fail. The jaw- muscles become paralyzed, the pulse is slowed, and the tem- perature diminished. There is sometimes vomiting, but no purging. The secretion of the kidneys is also checked. Dr. McSherry states 1 that he has seen all these symptoms produced by eating oysters, lobsters, and crabs unseasonably. In Russia a form of poisoning has often been observed which results from eating salted sturgeon. In the fresh state these fish are perfectly wholesome, but when salted and eaten raw they produce a very fatal illness. The mortality is said to reach 50 per cent, of those attacked. No cases traceable to this cause have been observed in this country. 1 Health and How to Promote it, p. 143. FOODS OF ANIMAL ORIGIN. 109 It has been shown, beyond question, that the flesh of beeves suffering, when killed, from splenic fever, will produce this disease in the human subject. In 1874 an extensive and violent outbreak of an acute disease, characterized by vomiting and purging, fever and dizzi- ness, occurred at Middelburg, in Holland. Three hundred and forty-nine persons were attacked, of whom 6 died. The out- break was traced to eating liver-sausage (Leberwurst), in which the characteristic bacillus of splenic fever was found on micro- scopic examination. In July, 1877, an outbreak of choleraic disease, from eating carbuncular meat, occurred in the town of Wurzen. In the latter epidemic the bacillus of splenic fever {Bacillus antJiracis) was found in the intestinal canal and in the blood of those attacked. In Detmold, in Germany, an outbreak of violent gastro- intestinal inflammation, accompanied by high fever, occurred. Among the 150 persons attacked 3 died. The disease was traced to eating the meat of a cow suffering, before death, from pleurisy (probably pleuro-pneumonia). In view of the somewhat extensive prevalence of this disease among cattle in this country at the present time, the record of this outbreak may suggest to sanitary authorities some measures for the prevention of similar epidemics on this side of the Atlantic. In July, 1880, 72 persons who had eaten of certain beef and ham-sandwiches in Welbeck, England, were attacked by choleraic diarrhoea; 4 of the cases died. Inflammation of the lungs and small intestines were the most prominent pathological conditions found post-mortem. The smaller blood-vessels of the kidneys were filled with finger-shaped bacilli, which, when cul- tivated and inoculated into guinea-pigs, rats, and white mice, produced similar pathological conditions. At Nottingham, England, in 1881, a number of persons were attacked by a similar train of symptoms after eating baked pork. One case terminated fatally out of the 15 attacked. It is uncertain whether the meat in these two instances was from diseased 110 TEXT-BOOK OF HYGIENE. animals or whether it had undergone partial decomposition. The former is the more probable supposition, although the organisms found were neither those of splenic fever nor swine plague, but resembled those of symptomatic anthrax (black leg or black quarter). Whether the flesh of tuberculous animals can communicate tuberculosis to the consumer is still an unsettled question. Foreign veterinarians and hygienists who have studied the question incline to the view that there is danger of such trans- mission. At the International Sanitary Congress of 1883, at Brussels, the subject was discussed, and M. Lydtin, the chief veterinary surgeon of the Grand Duchy of Baden, submitted the following propositions, which were adopted by the Congress : 1. That the flesh and viscera of tuberculous animals may be used as food, provided the disease is only commencing, the lesions extending but to a small part of the body, the lymphatic glands being still healthy; provided the tubercle centres have not undergone softening, and provided the carcass is well nour- ished and the flesh presents the characters of meat of the first quality. 2. That the flesh of animals showing very pronounced tuberculous infection should be saturated with petroleum, and afterward burned under the direction of the police. 3. That the milk from cows affected with pulmonary phthisis, or suspected of having it, should not be consumed by man or other animals, and the sale of it should be strictly prohibited. The congress for the study of tuberculosis, which met in Paris in 1888, adopted resolutions of a more decided character against the use of meat and milk from tuberculous animals. Certain animals can devour with impunity substances which are intensely poisonous to human beings. The flesh of the animals may be impregnated with these poisons, and cause serious and fatal illness in persons partaking of it. In this way may, perhaps, be explained the cases of poisoning sometimes following the eating of partridges and other birds. The prevention of disease from tainted meat is one of the FOODS OF ANIMAL ORIGIN. Ill most important problems of public hygiene. Food animals should be inspected by qualified inspectors before slaughtering, to exclude animals suffering from diseases that would vitiate the meat. When the meat is exposed for sale upon the dealer's stall it should be again inspected, and all found unfit for use as food confiscated and destroyed. Meat, in which the presence of trichina? or other parasites is suspected, should be examined microscopically. 1 Eggs. Although eggs contain a large amount of the pro- teid and fatty alimentary principles, 2 their value as food has probably been greatly overrated. The savory taste and ready digestibility of eggs has, however, rendered them a popular article of food. For obvious reasons, the eggs of the common barn-yard fowl are most frequently used, those of ducks and geese being far inferior in flavor to the first named, and being likewise less easily obtained. The method of cooking eggs is generally supposed to have considerable influence upon their digestibility. According to Dr. Beaumont's experiments made on Alexis St. Martin, raw eggs are digested in one and a half to two hours, fresh-roasted in two hours and fifteen minutes, soft-boiled or poached in three hours, and hard-boiled or fried in three and a half hours. These experiments are, however, of very little value as a basis for general conclusions. It is probable that a hard-boiled egg is quite as easily digested in the healthy stomach as a raw one, if care be taken to masticate it well and eat bread with it, so that it is introduced into the stomach in a finely-divided state. Eggs readily undergo putrefaction, when sulphuretted hydrogen is formed in them in large quantities. When this has taken place they are manifestly unfit to be used as food. 1 The prevention of the diseases of animals by National and State authorities is one of the most logical and thorough-going means of preventing disease from unwholesome meat. The American Public Health Association has for some years devoted considerable attention to the investigation of the diseases of animals and means for their prevention. The Department of the Interior of the National Government has likewise made the diseases of cattle and hogs a subject of study and published some valuable reports thereon. See analysis in Table VIII. 112 TEXT-BOOK OF HYGIENE. FOODS OF VEGETABLE ORIGIN. Bread. The various cereal grains, when ground into flour, are used in making bread. The flours of wheat, rye, barley, buckwheat, and Indian corn are almost exclusively used in bread- making. The bran or cortical portion of grain contains a larger percentage of proteid principles than the white internal portion ; hence, flours made from the whole grain (bran-flour, Graham flour) if finely ground are more nutritious than the white flours. The latter are, however, more digestible, and hence furnish a larger proportion of nutriment, because the principles contained in white flours are absorbed and assimilated to a greater degree. Good bread should be light, porous, and well baked. The lightness and porosity are due to carbon-dioxide gas imprisoned in cavities of the dough during the process of bread-making. By adding yeast to the dough a fermentation is caused in the latter, in consequence of which a portion of the starch is con- verted into sugar, and then into alcohol and carbon dioxide. During the process of mixing the dough the entire mass becomes permeated by the gas, which, on heating, expands and leaves the numerous large and small cavities throughout the loaf which indicate properly-made bread. Instead of yeast some persons use leaven, which is simply a portion of fermenting dough, saved from previous baking. A small quantity of this added to a mass of dough starts up the fermentation in a similar manner to that of yeast. The production of carbon dioxide by fermentation in the dough goes on at the expense of part of the starch. It has been proposed, therefore, to supply the carbon dioxide from without, thus saving the entire amount of the carbohydrates present in the flour. This is accomplished in two ways first, by the use df some alkaline carbonate or bicarbonate (bicarbonate of sodium, carbonate of ammonium), the carbon dioxide being set free on the application of heat ; or, secondly, by forcing the gas, previously prepared, into the dough by means of machinery. FOODS OF VEGETABLE ORIGIN. 113 Flour is not infrequently adulterated with chalk, gypsum, pipe-clay, and similar articles. These are easily detected by adding a mineral acid, which produces effervescence when it comes in contact with the alkaline carbonate used as adulterant. Potato- and bean- meals are also used as adulterants of the higher grades of flour. Bakers often mix alum with inferior grades of flour. This imparts a greater degree of whiteness to the bread, and, in addition, enables it to retain a large proportion of water, thereby increasing the weight of the loaf. Formerly diseased grain (ergotized rye) often caused out- breaks of disease when the flour made from the diseased grain was used in bread-making. At the present time such accidents rarely occur. In some parts of Italy it is said that an endemic disease pellagra is caused by the consumption of diseased Indian corn. The evidence in favor of this view is, however, not unquestioned. Potatoes and rice are often used with satisfaction as substi- tutes for bread. They both contain a large proportion of carbo- hydrates. Indian corn (hominy) and oatmeal are likewise wholesome and nutritious foods of this class. The leguminous seeds (beans, peas, lentils) furnish a food containing a large percentage of proteids. According to the analyses of Kcenig l the average composition of the most fre- quently used legumes in the dried condition is as follows : TABLE XIII. Beans. Peas. Lentils. ;Ground-nuts.* Water, per cent. . . . Solids, per cent. . . . 13.6 86.4 14.3 85.7 12.5 87.5 6.5 93.5 Proteids, per cent. . . Fats 23.1 2.3 53.6 3.9 3.5 22.6 1.7 53.2 5.5 2.7 24.8 1.9 54.7) 3.6) 2.5 28.2 46.4 15.7 3.2 Carbohydrates, per cent. Cellulose, per cent. . . Ash 1 Die Menschlicheu Nahruugs und (Jenussmittel, ii, p. 288. * The American pea-nut, the fruit or nut of Arachis hypogcea. 114 TEXT-BOOK OF HYGIENE. Beans, peas, and lentils are often added to other articles of food with advantage. In recent years an important article of food for armies has been made of various legumes ground into flour and mixed with fat, dried and powdered meat, salt, and spice. This constitutes the so-called " Erbswurst," or pea-sausage, which formed such an important part of the dietary of the German army in the Franco-German war of 1871. Bean- and pea- meals are also used sometimes as additions to other flours in bread- making. The dried leguminous fruits cannot be used as regular articles of diet, however, as they soon pall upon the taste, and produce indigestion, nausea, and other intestinal derangements. Green Vegetables. The plants usually classed together as " vegetables," the products of the market-garden or truck-farm, comprise cabbages, turnips, parsnips, onions, beets, carrots, tomatoes, lettuce, green peas and beans, and similar articles. They all contain a large proportion of water, a variable propor- tion of sugar, and a small percentage of proteid principles. Much of their palatability and digestibility depend upon the methods by which they are prepared for the table. All garden vegetables should be used soon after being gathered, as they rapidly undergo decomposition, and are liable to produce derangements of the digestive organs if used under these conditions. Fruits and nuts generally contain large quantities of sugar and fats. They form agreeable additions to other articles of diet, but are insufficient to sustain life. The use of fruits usually produces copious intestinal evacuations, and they are, therefore, especially to be recommended to persons of sedentary occupations, in whom torpidity of the bowels is so frequently present. Condiments. Various aromatic herbs and seeds are used as additions to other articles of food, to increase their sapidity and to promote a larger flow of saliva and gastric juice, and so assist digestion. Mustard, pepper, allspice, and vinegar are the principal condiments. Within certain limits they are not in- jurious, but the tendency in the use of all stimulants is to COOKING. 115 exceed a healthful limit. Condiments, as well as other stimu- lants, should be used in moderation. COOKING. Much more attention than is generally given should be paid by physicians to the culinary art. The manner in which food is cooked has no little influence upon its digestibility. There can be no question that the extreme prevalence of functional indi- gestion in this country is almost exclusively dependent upon bad cooking. The various methods of cooking are boiling, frying, roast- ing, broiling, and baking. By either of these methods food can be cooked so as to be palatable as well as digestible ; on the other hand, the choicest article can be utterly spoiled and rendered unfit to be taken into the human stomach. It depends, therefore, not so much upon the method of cooking, as upon the knowledge and art of the cook. Boiling. Meats of all kinds are rendered tender and di- gestible by boiling. In order to retain the flavor of meat, the water should be boiling when the meat is put into it. By the heat of the boiling water the albumen on the outside of the meat is coagulated and the juices and flavor retained within. After a few minutes the temperature of the water should be re- duced to 71 to 77 C. (160 to 170 R), and maintained at that height until the meat is tender. By this process a much more savory piece of beef, mutton, or fowl can be obtained than where the meat is put into cold water and thus gradually heated. The latter method is, however, the proper one to be followed when good soup or broth is desired. In boiling vegetables, as much care is necessary as in boil- ing meat or fish. Potatoes and rice should be steamed, rather than boiled. The difficulty of obtaining a good cup of coffee, especially in the northern portion of the United States, illustrates the pre- vailing ignorance upon one of the simplest points in the art of 116 TEXT-BOOK OF HYGIENE. cooking. Coffee should never be served in the form of a de- coction; that is to say, it should never be boiled. Properly made it is an infusion, like tea, which no one ever thinks of boiling. The difference between an infusion (especially if made by per- colation) and a decoction of coffee can only be appreciated by those who have enjoyed the one and endured the other. Frying. Frying, if properly done, is really nothing less nor more than boiling in oil or fluid fat of some kind. Olive- oil is preferable, but is not essential ; butter, beef-drippings, lard, or probably cotton-seed oil may be substituted for it without disadvantage. The principle of frying depends upon the fact that the temperature of oil can be raised to such a height as to produce instant coagulation of the surface of meat, fish, or other object immersed in it while hot ; this film of coagulated albu- men imprisons the juices and flavors of the meat or fish, and pre- vents the fat entering and soaking the fibres with grease. Small fish or birds, properly fried, are justly regarded as delicacies by connoisseurs, but the process of saturating these objects with fat while gradually heating them produces a dish that is anything rather than grateful to the palate, or conducive to good digestion. Roasting. The fame of " the roast beef of Old England " has passed into song, but, at the present day, beef and other meats are rarely roasted, either in this country or abroad. As Sir Henry Thompson well expresses it, 1 "the joint, which for- merly turned in a current of fresh air before a well-made fire, is now half stifled in a close atmosphere of its own vapors, very much to the destruction of the characteristic flavor of a roast." It is probable that the old method of roasting before an open fire produced not only the most savory, but likewise the most nu- tritious and digestible, meat. It is much to be regretted that the process has fallen so greatly into disuse. Broiling and Baking. These methods of cooking are modifications of the process of roasting. Meats or fish, care- fully broiled or baked, preserve their natural juices and flavors 1 Food and Feeding, p. 45. London, 1880. ALIMENTARY BEVERAGES. 117 to a great extent, and retain their digestibility and nutritious properties. Of all methods of cooking these are probably best known and most satisfactorily applied in this country. 1 ALIMENTARY BEVERAGES. The alimentary beverages may be divided into two classes, those depending for their effects upon the alcohol they contain, and those whose active principles reside in certain alkaloids. They are used chiefly as digestive and nervous stimulants. BEVERAGES CONTAINING ALCOHOL. The physiological action of alcohol has been pretty fully worked out by Binz and his pupils, and by other experimenters. From these researches, it appears that the first effect of taking alcohol, sufficiently diluted, into the stomach, is to increase the flow of the saliva and gastric juice. This effect is probably re- flex, and results from a stimulation of nerve terminations in the stomach. The alcohol is rapidly absorbed, and is carried in the blood, without undergoing chemical change, to the nervous centres, lungs, and tissues generally. In the brain the alcohol probably enters into combination with the nervous tissue, modifying the normal activity of the various centres, either increasing the activity, if the alcohol is in small quantity (stim- ulating effect), or diminishing it if in larger quantity (depressing effect), or entirely suspending the activity of the centres, if in sufficiently large quantity (paralyzing effect). Alcohol stimulates the vasodilator nerves, causing dilata- tion of the smaller vessels ; in consequence of this the blood is largely sent to the periphery of the body ; the blood-pressure diminishes, and heat-radiation is increased. At the same time a portion of the alcohol is used up in the lungs in the produc- tion of animal heat, thus economizing the expenditure of fats 1 Every one interested in the proper application of the principles of cookery should study the Lomb prize essay of the American Public Health Association, by Mary II in man Abel, upon "Practical. Sanitary, and Economic Cooking." This little book can be obtained of Dr. L A. Watson, Seeri-tary, Concord, N. H. ; price, 25 cents. See, also, an essay on "The Art of Cook- ing," by Edward Atkinson, L.L.D., in Popular Science Monthly, November, 1889. 118 TEXT-BOOK OF HYGIENE. and proteids, and acting as a true respiratory food. Alcohol does not contribute nutritive material to the body ; it only per- mits that which is stored up to be saved for other uses, by fur- nishing easily-oxidizable (combustible) material for carrying on the respiratory process, and supplying animal heat. During the use of alcohol the excretion of urea is dimin- ished. This shows that waste of tissue is retarded in the body. Regarding the statement of some authorities that alcohol does not undergo any change in the body, but is excreted unchanged, Binz asserts 1 that alcohol appears in the urine only when exceptionally large quantities have been taken, and then in very small proportion. It is not excreted by the lungs, the peculiar odor of the breath being due not to the alcohol, but to the volatile aromatic ether, which is oxidized with greater difficulty, and so escapes unchanged. While alcohol produces subjectively an agreeable sensation of warmth in the stomach and on the surface of the body, the bodily temperature is not raised. The subjective sensation is due to the dilatation of the blood-vessels and the sudden hyper- eemia of those parts. During fevers and other exhausting diseases, alcohol is invaluable to prevent waste of tissue and sustain the strength. It does not act merely as a stimulant to the circulation and nervous system, but, as above pointed out, saves the more stable compounds by furnishing a readily oxidizable respiratory food. When taken in small doses by healthy persons, alcohol diminishes the temperature by increasing heat-radiation. When large quantities are taken, the bodily temperature is reduced by diminishing heat production, as well as by increased radiation. This is shown in the condition known as dead-drunkenness, in which the temperature is sometimes depressed as much as 20 F. below the normal. Cases in which the temperature sank to 75, 78.8, and 83 F. have been reported, with recovery in all cases. 1 Bealencyclopaedie d. ges. Heilk., Bd. I, p. 183. BEVERAGES CONTAINING ALCOHOL. 119 The constant use of alcohol produces in all the organs an excess of connective tissue, followed by fatty degeneration and the condition known as cirrhosis. The organs most frequently affected are the stomach, liver, and kidneys. Serious pathological alterations also occur in the circulatory, respiratory, and nervous systems. Alcohol is not necessary to persons in good health. Prob- ably most persons, regardless of. their state of health, do better without it. Its habitual use in the form of strong liquors is to be unreservedly condemned. The lighter wines and malt liquors, if obtained pure, may be consumed in moderate quanti- ties without ill effects. Even in these forms, however, the use of alcohol should be discouraged or, perhaps, prohibited in the young. Neither in hot nor in cold climates is alcohol necessary to the preservation of health, and its moderate use even produces more injury than benefit. The Polar voyager and the East India merchant are alike better off without alcohol than with it. It has long been a prevalent belief that the use of alcohol enables persons to withstand fatigue better than where no alcohol is used. A large amount of concurrent testimony absolutely negatives this belief. 1 The predisposition to many diseases is greatly increased by the habitual use of alcohol. Sun-stroke, the acute infectious diseases, and many local organic affections attack, by preference, the intemperate. A recent collective investigation by the British Medical Association brought out the fact that croupous pneu- monia is vastly more fatal among the intemperate than among those who abstained from the use of alcoholic liquors. A further investigation by Baer has shown that the average expectation of life among users and dealers in alcoholic liquors is very much shortened. The following table gives a compara- tive view of the expectation of life in those who abstained from and those who used alcohol: 1 See Parkes' Hygiene, 6th ed., vol. i, pp. 315-327. 120 TEXT-BOOK OF HYGIENE. TABLE XIV. EXPECTATION OF LIFE. Age. Abstainers. Alcohol Users. At 25 32.08 years. 26.23 years. "35 25.92 " 20.01 " "45 19.92 " 15.19 " "55 14.45 " 11.16 " "65 9.62 " 8.04 " Table XV shows the influence of alcohol upon the mortality from various diseases : TABLE XV. General Male Popu- lation (per cent.). Alcohol Venders (per cent.). Brain disease 11.77 14.43 Tuberculosis 30.36 36.57 Pneumonia and pleuritis .... Heart disease 9.63 1.46 11.44 3.29 Kidnev disease . 1.40 2.11 */ Suicide 2.99 4.02 Cancer ... 2.49 3.70 Old age . 22.49 7.05 Alcohol as a beverage is consumed in the various forms of spirits, wines, and fermented liquors. The varieties of spirits most frequently used are brandy, whisky, rum, and gin. They are all procured by distillation. Brandy is distilled from fermented grape-juice, and has a characteristic aromatic flavor. When pure and mellowed with age it is the most grateful to the palate of all distilled spirits. Whisky is distilled from barley, rye, oats, corn, or potatoes. Each of these has a peculiar flavor, depending upon the par- ticular volatile ether formed during the distillation. Rye-, barley-, and corn- whiskies are almost exclusively used in this country. BEVERAGES CONTAINING ALCOHOL. 121 Rum is distilled from molasses, and is a favorite ingredient in hot punches. It is often used with milk, eggs, and sugar, in the preparation of eggnog, a highly-nutritious, stimulating drink, which is often prescribed with great benefit in acute and chronic wasting diseases. Gin is an ardent distilled spirit, flavored with oil of juniper. It has a widely-spread popular reputation as a cure for kidney diseases, but is probably oftener responsible for the production of these diseases than for their cure. All of the above-mentioned liquors contain from 40 to 60 per cent, of alcohol, and should always be diluted before being taken into the stomach, in order to prevent the local irritant effects of the alcohol upon the gastric mucous membrane. Wine is the product of the alcoholic fermentation of the saccharine constituents of fruits. Wine is usually derived from the grape, though other fruits may also furnish it. The stronger wines (sherry, port, madeira) contain from 16 to 25 per cent, of alcohol. The lighter wines (hock, red and white Bordeaux and Burgundy wines, champagnes) contain from 6 to 15 per cent, of alcohol. Some also contain considerable free carbonic acid (sparkling wines), of which the champagnes are types. The red and white Bordeaux and Rhine wines are probably the least objectionable of these beverages for habitual use. They contain sufficient alcohol to be lightly stimulant, have a pleasant acid flavor, and are least likely to produce the bad effects which usually follow in the wake of the habitual use of the stronger wines or ardent spirits. Preference should be given to the wines of domestic manu- facture, on account of the great probability of adulteration of the favorite brands of foreign wines. Many of 'the California, Vir- ginia, New York, and Ohio wines compare very favorably in flavor with those imported from abroad. The more reasonable cost of these domestic wines is also a point in their favor. Cider is the fermented juice of apples. It frequently pro- duces unpleasant gastric and intestinal disturbances when drunk, 122 TEXT-BOOK OF HYGIENE. on account of the large quantity of malic acid contained in it. Although it is usually ranked as a " temperance drink," it is quite capable of causing intoxication when consumed in large quantities. Beer is the fermented extract of barley, mixed with a decoction of hops and boiled. It should be prepared only of malt, hops, yeast, and water, and should contain from 3 to 4 per cent, of alcohol, 5 to 6 per cent, of extract of malt and hops, 2 to 4 per cent, of lactic and acetic acids, and from ^ to ^ per cent, of carbonic acid. This ideal is, how- ever, rarely attained in the article sold by the liquor dealer. Numerous adulterations are practiced on the unsuspecting con- sumer. The hops are frequently substituted by aloes, calamus, and ginger, or by the more deleterious picric acid or picrotoxin. The rich brown color, sweetness, body, and creamy foam are produced by caramel and glycerin. The more expensive barley- malt is substituted by starch and rice, or grape-sugar and molasses. Ale, porter, and brown-stout are merely varieties of beer some containing more sugar, others more extractive matter. Beer and its correlatives have considerable dietetic value, owing not merely to the alcohol they contain, but largely to the sugar and acids entering into their composition. When used to excess they often cause a considerable accumulation of fat. Kumys is the national beverage of the nomadic tribes of Tartary. It consists of the milk of mares which has undergone fermentation, partly lactic and partly alcoholic in character. Recently it has been introduced into Europe and also into this country, where it is made of cows' milk. It is a palatable, nutritious stimulant, and is often very useful as a dietetic article in disease. Kefyr is a product of the fermentation of milk which bears some resemblance to kumys. The following table (Table XVI) gives a comparative view of the composition of true kumys, the same prepared from cows' milk, and kefyr : ALKALOIDAL BEVERAGES. 123 TABLE XVI. True Kumys (percent.). Cows' Milk Kumys (percent.). Kefyr (per ce'nt.). Proteids . 2.20 2 35 3 12 Fats 2.12 2.0T 1 95 Su^ar 1.53 1.81 1 62 Lactic acid 0.90 40 83 Alcohol 1.72 1.90 2 10 C0 0.85 0.80 92 THE ALKALOIDAL BEVERAGES. The virtues of the alkaloidal beverages depend upon certain alkaloids which differ very little in their chemical composition or physiological effects, and upon certain volatile aromatic con- stituents of the various articles used. The principal articles employed in the preparation of these beverages are coffee, tea, chocolate, mate, and coca. It is estimated that 500,000,000 people drink coffee, 100,000,000 tea, 50,000,000 chocolate, 15,000,000 mate or Paraguay tea, and 10,000,000 coca. All of these are active nervous stimulants and retarders of tissue- waste. They are all liable to produce serious functional dis- turbances of the nervous, digestive, and circulatory systems if used to excess. Anaemia, digestive derangements, constipation, pale, sallow complexion, loss of appetite, disturbed sleep, nervous headaches and neuralgias are the most marked of these effects. On the other hand, when taken in moderate quantity, the alkaloidal beverages enable the consumer to withstand cold, fatigue, and hunger ; they promptly remove the sensation of hunger, and diffuse a glow of exhilaration throughout the body. Coffee. Coffee is the ripe fruit (seed) of the Cnffea Arabica, a native of Arabia and Eastern Africa, but now cultivated in other tropical regions of the world. The fruit consists of two flat-convex beans, the flat surfaces of which are apposed to each other. These are enclosed in a fibrous envelope which is some- times used as a cheap substitute for the coffee-bean. The beverage, coffee, is an infusion of the roasted and 124 TEXT-BOOK OF HYGIENE. ground bean in hot water. Its virtues depend upon the alkaloid, caffein, and an aromatic oil. The latter, being volatile, is driven off by long-continued heat. Hence boiled coffee lacks the grateful aroma of that which is made by simply infusing the ground bean in hot water. The great demand for coffee and its comparatively high price have caused it to be extensively adulterated and substituted by other natural and artificial products. Artificial coffee-beans have been made of clay, dough, or extract of chicory, colored to imitate the natural bean. The -fraud is easily detected by placing the beans in water, when the artificial product soon falls to pieces, while the natural beans undergo no change of shape or consistence. Ground coffee as found in the stores is usually adulterated. The materials used for sophistication are : The grounds of coffee previously used, the roasted root of chicory, acorns, rye or barley, carrots, sunflower-seeds, caramel, and a number of articles of similar value, generally harmless. Tea. The plants which furnish the tea-leaves are natives of China, Indo-China, and Japan. The tea-leaves contain a crystalline alkaloid, thein, identical in composition and proper- ties with caffein. The various sorts of tea found in the market (green and black teas, etc.) differ only in the relative proportion of tannin and thein contained in each. The aromatic principle also varies somewhat in the different sorts. Tea is adulterated to quite as great an extent as coffee, the leaves of various plants bearing more or less resemblance to tea- leaves being added to the latter. Much of the tea found in the market is colored artificially with Prussian blue and iron oxide. These additions are harmless, as they are not soluble in water. Cliocolate. Cocoa, from which chocolate is derived, is widely different in composition from tea and coffee. In addi- tion to its active principle, theobromin, which is identical with caffein and thein, it contains nearly 50 per cent, of fat, which renders it an article of high nutritive value. TOBACCO. 125 Mate, or Paraguay tea, guarana, and coca are used to a considerable extent in some parts of South America as substi- tutes for coffee and tea. Their composition is not well known, but their effects are believed to depend upon alkaloidal princi- ples similar to caffein and thein. TOBACCO. Closely connected with the subjects treated in this chapter are the effects of the constant use of tobacco upon the human system The depressing effects of tobacco, due principally to the nicotine upon the nervous and digestive systems, have long been recognized. Recently, however, it has been found that very serious symptoms are produced upon the sense of vision by the constant or excessive use of tobacco. A special form of amaurosis, termed tobacco amaurosis, has been frequently noticed since attention was first called to it by Mackenzie. [The following additional works are recommended to the student : Thos. K. Chambers, on Diet in Health and Disease. Edward Smith, on Foods. Forster, Ernahrung, in Pettenkofer u. Ziemssen's Handbuch der Hygiene. Munk und Uffelmann, Die Ernahrung des Gesunden und K ran ken Menschen. I. Barney Yeo, Food in Health and Disease. Kenwood, The Hygienic Laboratory, Part V.] QUESTIONS TO CHAPTER III. FOOD. What is a food ? What reasons have we for stating that the proxi- mate food principles must be combined in definite proportions to main- tain a normal degree of health? What are the alimentary principles necessary to man's existence ? Why do we need water ? What are the functions of the salts in our foods ? Is existence possible without a sufficient supply of nitrogenous food ? What is the relation of starch to fat as oxidizable food ? Are the proteid tissues of the body derived solely from the nitroge- nous foods? What are the sources of the body-fat? What tissues are mostly consumed during work? What is the relation between the proximate food principles, and what amount of each is necessary in the standard daily diet of a man at rest? At moderate labor? At hard work? About what is the relation of nitrogenous to non-nitrogenous food ? Of nitrogen to carbon ? Is a standard diet necessarily an expensive one? How may it be selected ? Why is a variety in the kind of food necessary ? Why may not a man live on nitrogenous foods, like meat, alone? Why not on non- nitrogenous food, like potatoes ? Has climate much influence upon the amount of food needed ? Has it upon the kind of food ? What kind of food is especially beneficial for a laboring man in cold weather? Where do we find the proteid prin- ciples of food ? Where the fatty ? Where the carbohydrates ? The salts ? Why should only a moderate amount of food be taken, and why should it be properly prepared? What are some of the factors that increase the consumption of carbonaceous foods ? Does increased physical labor increase the demand for nitrogenous foods? Which requires the most carbonaceous food, physical or mental labor? What maladies especially require fat-producing foods ? Has the food that a man eats anything to do with his moral character ? How may we classify food? Name some of animal origin. From the vegetable kingdom. What is the function of condiments? Of stimulants ? Why is milk so nearly a perfect food ? What is the average compo- sition of cows' milk? What is the difference between human milk and cows' milk ? What other substitutes are sometimes used for human milk? (126) QUESTIONS TO CHAPTER III. 127 What is cream? What changes take place in milk upon standing for some time? To what are these changes due? What is made from the curd? Has whey, or butter-milk, any food value? What should be the specific gravity of milk? How is it deter- mined? What may lower the specific gravity? What may raise it? Has " skim-milk " a food value ? What is the objection to its sale ? How is milk frequently adulterated? How may this be detected? Why is the addition of water dangerous? How else might the milk become infected ? May infectious diseases be transmitted from the cow to man through the milk? How may this danger of infection be avoided? What diseases are especially likely to be thus conveyed by the milk ? Give an account of the l> Hendon cow disease." May the milk of animals suffer- ing from certain febrile diseases be dangerous to health ? Is the milk of cows fed on distillery or brewery refuse necessarily unwholesome ? How may the quality of a milk be determined ? What is a lacto- scope? What is a creamometer ? What should be the minimum per- centage of cream ? How may the rapid fermentation of milk be pre- vented? What is tyrotoxicon, and to what is it due? What is butter ? What is its food value, and why ? What change does it undergo in becoming "rancid"? How is it often sophisticated? What is oleo-marg.irine or butterine? How is it made? Is it unwhole- some, and is there any objection to its use if sold under its proper name? Upon what does the value of cheese depend ? Is it nutritious ? Why cannot large quantities be eaten at a time ? Which are the richest kinds of cheese? Is cheese often adulter- ated ? How may cheese be made more digestible ? What dangerous change may it undergo, and to what is this due ? Why is meat such an important article of food? What is the per- centage of proteids and fats in the meats commonly used ? Upon what does the variation between these two principles depend ? Should meat be cooked and eaten immediately after death ? Should it be kept too long after death before being used ? Why should meat be always cooked ? What are the common methods of cooking ? Are beef-extracts really nutritious ? Are partially or wholly predigested preparations of meat nutritious? What is the objection to their continued use? What conditions may render meat unfit for food ? How may the various parasites in meat be destroyed? What animals are apt to be infested with trichinae ? In what two forms are the trichinae found in ani- mals ? How do they gain access to the muscles ? May salted or smoked 128 QUESTIONS TO CHAPTER III. meat contain living trichinae ? Of what parasite is the Cysticercus cellu- losa a transition form ? What may be the result of using partially-decomposed meat or fish? To what are the serious results due? How are the ptomaines produced? What is their probable chemical nature? What peculiar idiosyncrasy have some people regarding shell-fish ? What infectious diseases may be transmitted to human beings by the consumption of infected meat ? When and by whom should meat be inspected ? Why are eggs so highly valued for food ? In which form are eggs most digestible ? Why do eggs undergo putrefaction so readily ? What cereals are used in making bread ? What part of the grain contains the greater proportion of proteids? Is all the gluten- to be found in the bran? Which flours are most nutritious and which most digestible? What are some of the characteristics of good bread? To what is the porosity due, and how is it produced? How may the loss of starch by fermentation be avoided ? How is flour often adulterated ? Why is alum added to flour? What disease of grain may be harmful to the health of the users ? What is the chief constituent of potatoes and rice ? In what prin- ciple are the leguminous foods especially rich ? Wherein is the chief value of green vegetables? Why are fruits and nuts valuabe as articles of diet ? What rule should be observed regarding the use of condiments ? Why should physicians know considerable about cooking? What are the various methods of cooking? What is the effect of boiling upon meats? What points are to be observed in the boiling of meat? In the making of soups, etc. ? What valuable principle is lost if vege- tables are boiled too long? What is the secret in making good coffee? What is frying? Ho\v should it be done? How should meats be roasted ? Why are broiling and baking generally satisfactory processes? Into what two classes may alimentary beverages be divided ? For what are those of the second class used ? What is the pl^siological effect and action of alcohol upon the nerve-centres ? Upon the circulation ? Is it changed before absorption ? Does it nourish the body ? Does it supply heat ? Does it raise the body-temperature ? What effect has it on heat- production and heat-radiation? On tissue waste? How is it excreted? What effect have small amounts of alcohol upon digestion ? What patho- logical changes are brought about by the constant use of alcohol ? Is it necessary or beneficial to persons in good health? Why is it so valuable in fevers and wasting diseases? Does it enable persons to withstand fatigue ? To what diseases is the predisposition increased by the habitual use of alcohol? What effect has it upon the expectation of life and QUESTIONS TO CHAPTER III. 129 upon the mortality from various diseases ? If used habitually, what forms should be chosen ? What is the difference between spirits, wines, and malt liquors? What is brandy? From what is whisky made? How much alcohol do the various spirits contain, and what rule should be observed regarding their use ? What percentage of alcohol do the various wines contain ? Which are the least objectionable for habitual use ? What can be said regarding the domestic wines? To what disturbances may cider give rise, and why ? From what articles alone should beer be made ? How much alcohol should it contain ? With what substances is it often sophisticated ? Have beer, ale, etc., a dietetic value, and why ? What may be the result when beer is used to excess? What is kumyss and kefyr ? Why are they valuable in sickness ? How much alcohol does each contain? Upon what do the virtues of the alkaloidal beverage depend? What are the principal articles employed in their preparation ? What is the physiological action of all these substances ? What are some of the effects if they are used to excess? What is their effect when used in moderation ? May they be used as substitutes for alcohol ? What is coffee, and what alkaloid does it contain ? What else does it contain that gives value to the beverage? How is coffee adulterated, and how may fraud be detected ? What is tea, and what alkaloid does it contain ? How may it be adulterated ? Why is cocoa of greater food value than tea or coffee ? What is its active principle, and what is its relation to thein and caffeiu ? What is the difference between cocoa and chocolate ? What are the effects of tobacco upon the human system, and to what are they due ? CHAPTER IV. SOIL. HIPPOCRATES treated at length, in one of his works, of the sanitary influences of the soil. Others of the older writers, especially Herodotus and Galen, called attention to the same subject, and Vitruvius, the celebrated Roman architect, who flourished about the beginning of the Christian era, taught that a point of first importance in building a dwelling was to select a site upon a healthy soil. From this time until the beginning of the eighteenth cen- tury, very little of value is found in medical literature bearing upon this subject. In 1717, however, Lancisi published his great work on the causes of malarial fevers, in which he laid the foundation for the modern theory of malaria, and pointed out the relations existing between marshes and low-lying lands and those diseases by common consent called malarial. Other authors of the eighteenth and the early part of the nineteenth centuries refer to the connection between the soil and disease, but exact investigations have only been made within the last thirty years. When it is considered that the air that human beings breathe, and much of the water they drink, are influenced in their composition by the matters in the soil, the great importance of possessing a thorough knowledge of the physical and chemical conditions of the soil becomes evident to every one. PHYSICAL AND CHEMICAL CHARACTERS OF THE SOIL. In the hygienic, as in the geological sense, rock, sand, clay, and gravel are included in the consideration of soils. The soil, as it is presented to us at the surface of the earth, (131) 132 TEXT-BOOK OF HYGIENE. is the result of long ages of disintegration of the primitive rocks by the action of the elements, of the decomposition of organic remains, and, possibly, of accretions of cosmical dust. The principal factor, however, is the action of water-upon rock, in leveling the projections of the earth's surface produced by volcanic action. Soils vary considerably in physical and chemical constitu- tion. A soil may, for example, consist exclusively of sand, of clay, or of disintegrated calcareous matter. Other soils may consist of a mixture of two or more of these, together with vegetable matter undergoing slow oxidation. In forests, a layer of this slowly-decomposing vegetable matter of varying thick- ness is found, covering the earthy substratum. This organic layer is called humus, and when turned under by plough or spade, and mixed with the sand or clay base, it constitutes the ordinary agricultural soil. THE ATMOSPHERE OF THE SOIL, OR GROUND-AIR. The interstices of the soil are occupied by air or water, or by both together. The soil's atmosphere is continuous with, and resembles in physical and chemical properties, that which envelops the earth. Its proportion to the mass of the soil depends upon the degree of porosity of the soil, and upon the amount of moisture present. In a very porous soil, such as, for example, a coarse sand, gravelly loam, or coarse-grained sand- stone, the amount of air is much greater than in a clayey soil, granite, or marble. So, likewise, when the soil contains a large proportion of water, the air is to this extent excluded. The porosity of the various soils, as evidenced by the amount of air contained in them, is much greater than would, at first thought, be supposed. Thus it has been found that porous sandstone may contain as much as one-third of its bulk of air, while the proportion of air contained in sand, gravel, or loose soil may amount to from 30 to 50 per cent. The ground-air is simply the atmospheric air which has THE ATMOSPHERE OF THE SOIL, OR GROUND-AIR. 133 penetrated into the interstices of the soil and taken part in the various chemical decompositions going on there. In consequence of these chemical. changes the relative proportions of the oxygen and carbonic acid in the air are changed oxygen disappearing and giving place to carbon dioxide. It is well known that during the decay of vegetable matter in the air carbon dioxide is formed; one constituent of this compound, the carbon, being derived from the vegetable matter, while the oxygen is taken from the air. Hence, if this action takes place where their is not a very free circulation of air, as in the soil, the air there present soon loses its normal proportion of oxygen, which enters into combination with the carbon of the vegetable matter to form carbon dioxide. Thirty years ago, MM. Boussingault and Levy, two dis- tinguished French chemists, examined the air contained in ordinary agricultural soil, and found that the oxygen was diminished to about one-half of the proportion normally present in atmospheric air, while the carbon dioxide was enormously increased. The exact results obtained by Boussingault and Levy were as follow: In 100 volumes of ground-air there were 10.35 volumes of oxygen, 79.91 volumes of nitrogen, 9.74 volumes of carbon dioxide. In atmospheric air, on the other hand, there are in 100 volumes 20.9 volumes of oxygen, 79.1 volumes of nitrogen, 0.04 volume, or about --% of 1 per cent, of carbon dioxide. In spite of the striking results obtained by these two chemists, very little attention was paid to them by sanitarians, as very few seemed to have any clear notion of the relations exist- ing between the motions of the air above-ground and that under- ground. In 1871, however, Professor von Pettenkofer, of Munich, published the results of his own examinations into the constitu- tion and physical conditions of the ground-air, and the relations of the latter to the propagation of epidemic diseases. These re- searches, which created a wide-spread interest in the subject, 134 TEXT-BOOK OF HYGIENE. were extended by other observers in all parts of the world. These observers, prominent among whom were Professors Fleck, Fodor, and Soyka, in Germany ; Drs. Lewis and Cunningham, in India ; Prof. William Ripley Nichols, in Boston ; and Sur- geons J. H. Kidder and S. H. Griffith, of the U. S. Navy, in Washington, demonstrated that the increase of carbon dioxide in the ground-air is due to increased vegetable decomposition and to lessened permeability of the soil. A permeable, that is to say, a sandy or gravelly soil is likely to contain less carbon dioxide in its atmosphere than a dense, less permeable clay, although the amount of decomposition going on and the pro- duction of carbon dioxide in the former may considerably ex- ceed the latter. In the loose, sandy soil the circulation of the air is less obstructed, and the carbon dioxide may easily escape and be diffused in the superincumbent air, while the close-pored clay imprisons the carbon dioxide and prevents or retards its escape into the air above. The disappearance of oxygen from the ground-atmosphere is coincident with the production of an equivalent amount of carbon dioxide. It appears from this that in the soil an OX' idation of carbonaceous substances takes place, the product of which is found in the excess of carbon dioxide in the ground-air. Professor Nichols has found the proportion of carbon di- oxide in the air taken from a depth of 3 metres below the surface in the "made-land" of Boston to amount to 21.21 per thousand, the observation having been made in August. In December, at a depth of 2 metres, the proportion was 3.23 per thousand. Fodor, in Buda-Pesth, found the proportion of carbon dioxide to be 107.5 per thousand (over 10 per cent.), the air having been taken from a depth of 3 metres. The ground-air also teems with micro-organisms of various kinds, these being occasionally pathogenic. While in the great majority of instances the micro-organisms found are ordinary mold or fermentation fungi and bacteria of decay and putrefac- tion, disease-producing bacilli have also been observed in a THE ATMOSPHERE OF THE SOIL, OR GROUND-AIR. 135 number of instances. Among the latter are the bacillus of tetanus (Nicolaier), of anthrax (Frank), of malaria (Klebs and Tommasi-Crudeli), 1 of malignant cedema (Koch and Gaffky), and of typhoid fever (Tryde). It may not be inappropriate to refer here to the claim of Professor Domingos Freire, of Brazil, to the discovery of the germ of yellow fever in the soil of a burial ground near Rio Janeiro. The exhaustive investigations of Surgeon-General G. M. Stern berg, of the U. S. Army, under the direction of the government, have disposed effectually of the claims and pre- tensions of the Brazilian scientist, and established the fact that Freire's organism has no pathological significance whatever, at all events, that it has no relation to yellow fever. Cholera bacilli have not been found in the soil, but C. Frankel has shown experimentally that they can grow and multiply in the soil at various depths. At a depth of 1^ metres their development was constant and progressive throughout the year. When the soil is dry, these organisms may be carried hither and thither in the movements of the ground-air, and thus infect the air of contiguous localities, or be transported to a distance. Movements of the ground-atmosphere are principally due to differences of pressure and temperature in the air above- ground. Owing to such differences the air from the soil fre- quently permeates houses, entering from cellars or basements. In winter, when the air of houses is very much more heated (and consequently less dense) than the air out-of-doors, the difference of pressure thus caused draws the ground-air up through the house, while the cold, external atmosphere pene- trates the soil and occupies the place of the displaced ground- air. 2 A similar effect occurs in consequence of heavy rains. 1 While the pathogenic significance of Klebs' bacillus malarife is not generally accepted, it is thought proper, for the sake of completeness, to include it among the organisms sometimes found in the soil. * It is, of course, not strictly correct to say that the air is drawn up through the house by the diminution of pressure ; it being rather forced out of the soil by the colder and denser outside air ; but the phrase is sufficiently exact and will be readily understood. 136 TEXT-BOOK OF HYGIENE. The water fills up the interstices of the soil near the surface, and forces the ground-air out at points where the pores remain open. These places are the dry ground under buildings, where the air escapes and passes through floors and ceilings into the house above. Heavy rains may thus be the cause of pollution of the air in houses. The greater the porosity of the soil, the more likely is this to happen. This pollution of the house-air may be prevented by having impervious floors and walls to cellars and basements, or by interposing a layer of charcoal between the ground and the floor of the house. The latter does not prevent the passage of the ground-air, but the charcoal layer absorbs or arrests the noxious matters, filters the ground-air, as it were. In the spring and early summer the ground being colder than the air above it, and the ground-air consequently heavier and denser, the latter is not easily displaced. It is, perhaps, due to this fact that those infectious diseases which are proba- bly dependent upon the movements of the ground-air are less prevalent in the spring and early summer than in the latter part of the summer, autumn, and early winter. In the autumn the ground-air being warmer than the air above ground is easily displaced by the latter and forced out into the streets and houses to be inspired by men and animals. The same conditions may explain the greater likelihood of infection at night, which is proven for such diseases as malarial and yellow fevers. The colder outside air penetrates the interstices of the soil and forces out the impure ground-air. The researches of Fodor have demonstrated that the pro- portion of carbon dioxide in the ground-air may be taken as an approximative measure of the impurity of the soil whence the air is taken. The influence of the permeability of the soil, as before pointed out, must, however, not be overlooked in esti- mating the signification of the carbon dioxide. Fodor has shown that the proportion of carbon dioxide in the ground-air, and consequently the amount of organic decomposition, is THE ATMOSPHERE OP THE SOIL, OR GROUND- AIR. 137 greatest in July and least in March. That the carbon dioxide is derived from the decomposition of vegetable matter has been proven by Pettenkofer. This observer examined specimens of air brought from the Lybian desert, and found that the propor- tion of carbon dioxide in the ground-air was exactly the same as in the air collected above-ground. There being no vegetable growth in the desert there can, of course, be no vegetable decomposition going on in the soil. The excess of carbon dioxide in the ground-air is an indi- cation of the deficiency of oxygen, as has been shown. The air at a depth of 4 metres below the surface was found to contain only from 7 to 10 per cent, of oxygen one-half to one- third of the normal proportion. Many basements occupied by pe'ople as living-rooms extend from 1 to 3 metres under-ground, and hence are liable to be supplied with an atmosphere approach- ing in impurity that just mentioned. It requires no very vivid imagination to appreciate the dangers to health that lurk in such habitations. THE WATER OF THE SOIL, OR GROUND-WATER. At a variable depth below the surface of the ground, a stratum of earth or rock is found through which water passes with difficulty, if at all. Above this there is a stratum of water which moves from a higher to a lower level, and which varies in depth at different times according to the amount of precipita- tion (rain- or snow- fall), and according to the level of the nearest body of water toward which it flows. This stratum of water is termed the ground-water, and has within the last few years assumed considerable importance from its apparently close rela- tions to the spread of certain of the infectious diseases. The direction of horizontal flow of ground-water is always toward the drainage-area of the district. Thus, it is usually toward lakes, rivers, or the sea. Rains, or a rise in the river, cause a rise in the ground-water, while long-continued dry weather, or a low stage of the river which drains off the ground-water, 138 TEXT-BOOK OF HYGIENE. rnr.srs a fall in the latter. On the sea-coast the ground-water oscillations probably correspond with the tides. The writer is not aware of any observations made to determine this point, with the exception of a single instance mentioned by Dr. De Chaumont. In Munich, where the ground- water flows toward the river Isar, which divides the city, it has been found that the annual range or oscillation (the difference between the highest and lowest level during the year) is 3 metres, while the hori- zontal movement amounts to 5 metres per day, In Buda-Pesth the annual range was found by Fodor to be less than 1 metre, while in some portions of India it amounts to more than 12 metres. As it is from the ground-water that the greater portion of the supply of drinking-water in the country and in villages and small towns is drawn, it becomes at once manifest how important it is to prevent, as far as possible, pollution of this source. Cess-pools and manure-heaps and pits, of necessity, contaminate the soil and also ground-water for a distance below and around them, and such water is clearly unfit for drinking and other domestic purposes. Hence, the reason why wells should not be placed too near privies and manure-heaps or pits becomes apparent. Between the level of the ground-water, or that portion of the soil where its pores are entirely occupied by the water where, in other words, the ground is saturated and the surface, is a stratum of earth more or less moist ; that is to say, the interstices of the soil are partly filled with water and partly with air. It is in this stratum that the processes of organic decay or putrefaction are most rapidly going on, in consequence of which the pollution of the ground-air occurs. The oxidation of non- nitrogenous matter in the soil results in the formation of carbon dioxide. On the other hand, nitrogenized compounds are oxidized into nitric acid and nitrates. When, however, putre- faction occurs, nitrous acid, or nitrites and ammonia, are formed, the oxidation not proceeding far enough to result in nitric acid. Recent observations seem to show that these processes of THE WATER OF THE SOIL, OR GROUND- WATER. 139 decomposition are initiated and kept up by minute organisms termed bacteria, just as fermentation in liquids containing sugar can only take place in the presence of the yeast-plant. It has been found that when non-putrefactive decomposition goes on, there are always present multitudes of one variety of these minute organisms; while if putrefactive decomposition is going on, a number of other varieties of these organisms are present. Just as, when a fermenting liquid becomes putrid, the yeast-plant disappears and its place is taken by the ordinary bacteria of putre- faction, so in the soil, if the access of oxygen, which is necessary to the life of the bacteria of decay, is prevented, these organisms die* and are succeeded by the organisms of putrefaction. It has been found that in a soil saturated with water the bacteria of decay cannot live, while those of putrefaction may flourish, because these latter organisms can sustain life and develop in the absence of oxygen. Professor Fodor's researches indicate that the most prominent organism of non-putrefactive decomposition or decay is that which is termed by Cohn bacterium lineola; and that the bacterium termo is the principal organism of putrefaction. DISEASES SPREAD BY SOIL IMPURITIES. Given now an area of soil, say the ground upon which a house or city is built, with a moist stratum in which the pro- cesses of decay are active, and imagine a rise in the ground- water. The ground-air, charged with carbon dioxide and other products of decomposition, is forced out of the pores of the soil by the rising ground-water, and escapes into the external air, or through cellars and basements into houses, and may there produce disease. But the saturation of the soil with water pre- vents the further development of the bacteria of decay, and this is checked, or putrefaction may take place. If now the ground- water sinks to its former level or below, the processes of decay again become very active in the moist stratum, and large quan- tities of carbon dioxide and other inorganic compounds are produced. If the germs of infectious or contagious diseases 140 TEXT-BOOK OF HYGIENE. have been introduced into the soil, they also multiply and may escape with the movements of the ground-air into the external atmosphere, and there produce their infective action. This, it is held by Pettenkofer and his followers, is what actually occurs in cholera and typhoid fever. Professor DeChaumont has laid down the rule that a soil with a persistently low stage of ground- water, say 5 metres below the surface of the ground, is healthy ; a persistently high stage of ground- water, less than 1 J metres below the surface, is unhealthy ; while a fluctuating level of the ground-water, especially if the changes are sudden and violent, is very unhealthy. This would lead us to expect that places where this fluctuation is very great would show a large mortality from such diseases as are attributed to impurities in the soil. And this we find especially true in India. In certain localities in India, cholera, for example, is endemic ; that is to say, the disease is never entirely absent in such localities. Calcutta is one of these places. The rainy season begins about the first of May and continues until the end of October. During the next six months there is very little rain. It is fair to assume that the ground-water rises during the rainy season and checks decay and the multiplication of the germs of the disease in the soil, and that these processes become more active as the dry season advances and the ground-water level falls. If we note the death-rate from cholera in Calcuta it will be found that it bears a distinct relation to the movement of the ground-water. The deaths from cholera begin to increase from October and reach their height in April. Dr. Macpherson, who has written a very elaborate history of Asiatic cholera, shows this relation very clearly. For twenty-six years the average rain-fall was 157 cen- timetres. From May to October 1 42 centimetres fell, while the remaining 15 centimetres fell from November to April. The average number of deaths from cholera annually was 4013. Of these, 1238 died in the rainy season, while 2775, nearly three-fourths, died during the period of dry weather. In the cholera epidemics of 1866 and 1873 in Buda-Pesth, DISEASES SPREAD BY SOIL IMPURITIES. 141 the same relations existed between the ground- water and the cholera. As the level of the ground-water rose the cholera diminished, while the disease increased upon the sinking of the ground-water. Exactly the same behavior was exhibited by the disease in Munich in 1873. There seems good reason to believe that typhoid fever is propagated in consequence of movements of the ground-water, in the same way as above explained for cholera. This does not exclude the infection of drinking-water by the disease-germ, since much of the drinking-water used, as before stated, is drawn from the ground-water. Pettenkofer, Buhl, and Virchow have shown that the death-rate from typhoid fever has a distinct and definite relation to the ground- water oscillations. This has been incontestably proven for two cities, Munich and Berlin. When the level of the ground-water is above the average, typhoid fever decreases; when it is below the average, the number of cases becomes greater. Dr. H. B. Baker has demonstrated that the fluctuation of the ground-water level in the State of Michigan is similarly followed by a change in the morbility and mortality from typhoid fever. 1 Hence, it may be regarded as an established law that the rise and fall of the ground-water bears a definite relation to the morbility rate of typhoid fever. Nearly thirty years ago Dr. Henry I. Bowditch, of Boston, called attention to the frequent connection between cases of pulmonary consumption and dampness of the soil upon which the patients lived. After a very extended and laborious investi- gation Dr. Bowditch formulated these two propositions: " First. A residence in or near a damp soil, whether that dampness be inherent in the soil itself or caused by percolation from adjacent ponds, rivers, meadows, or springy soils, is one of the principal causes of consumption in Massachusetts, probably in New England, and possibly other portions of the globe. " Second. Consumption can be checked in its career, and 1 The Relation of the Depth of Water in Wells to the Causation of Typhoid Fever, Public Health, vol. x, p. 184-213. 142 TEXT-BOOK OF HYGIENE. possibly nay, probably prevented in some instances by atten- tion to this law." 1 Dr. Buchanan, of England, about the same time showed that the thorough drainage of certain English cities had mark- edly diminished the deaths from consumption in the drained cities. So far as the writer is aware, not a single fact has been established which militates against the law laid down by Dr. Bowditch, and so strongly supported by the statistical researches of Dr. Buchanan, yet hardly any notice has been taken of these results by physicians. Few know anything of them, and still fewer seem to have made practical use of such knowledge in advising patients. As corroborative of the views of Dr. Bow- ditch, the rarity of consumption in high and dry mountainous districts or plateaus may be cited. A recent study of the topographical distribution of con- sumption in the State of Pennsylvania, by Dr. William Pepper, apparently confirms Dr. Bowditch's conclusions in nearly every particular. It is now known that the direct cause of consump- tion is the bacillus tuberculosis, discovered by Dr. Robert Koch. The relation between soil-moisture and the increase of consump- tion will probably be found in the more favorable conditions of development of the tubercle bacillus furnished by a moist medium. DISEASES OF ANIMALS PROBABLY DUE TO SIMILAR CONDITIONS OF THE SOIL. The modern study of the sanitary relations of the soil is still in its infancy. Whatever definite knowledge has been gained relates merely to physical or chemical conditions of the soil and its atmosphere and moisture, or possibly the relations of these to the spread of certain diseases in human beings. But there is, perhaps, a wider application that may be made of such knowledge than has been heretofore suggested. The domestic animals which form such a large portion of the wealth of this > Consumption in New England and Elsewhere, 2d eel., p. 87. Boston, 1866. DISEASES OF ANIMALS DUE TO SIMILAR CONDITIONS OF SOIL. 143 country horses, cattle, sheep, and hogs are liable to infectious and contagious diseases, as well as are human beings, and many millions of dollars are lost annually by the ravages of such diseases. Now, from what is known of such diseases as splenic fever among cattle, and of the so-caUed swine plague, it does not appear improbable to the writer that the source of infection is a soil polluted by the poisonous germ of these diseases, just as it seems demonstrated that cholera and typhoid fever and possibly malarial fevers are so caused. The laborious investiga- tions of M. Pasteur in France have shown that the cause of splenic fever, when once introduced into a locality, will remain active for months, and even years, and it seems probable that a study of the soil in its relations to the diseases of domestic animals is a subject to which attention may profitably be given. It is well known that milch-cows frequently suffer from a disease identical in its nature with consumption in human beings. It is believed by many that the milk of such animals is not only unfit for food by reason of its poor quality, but that it may convey the disease to human beings when used as food. The observations of Bowditch and Buchanan, quoted above, show that consumption in man may be, and doubtless is, frequently caused by soil-wetness. It seems probable that the same cause should produce similar effects in the lower animals, and it is the writer's firm conviction that an examination into the circumstances under which cows become attacked by con- sumption would prove this probability a fact. DRAINAGE. In many soils drainage is necessary in order to secure a constant level of the ground-water at a sufficient depth below the surface. Drainage and sewerage must not be confounded with each other. Drainage contemplates only the removal of the ground-water, or the reduction of its level, while sewerage aims to remove the refuse from dwellings and manufactories, 144 TEXT-BOOK OF HYGIENE. including excrementitious matters, waste-water, and other products, and in some cases the storm-water. Sewers should never be used as drains, although for economy's sake sewer- and drainage- pipes may be laid in the same trench. Sewer-pipe must be perfectly air-tight and water- tight to prevent escape of its liquid or gaseous contents into the surrounding soil and rendering it impure. Drainage-pipe, on the other hand, should be porous and admit water freely from without. Escape of the contents of the drain-pipe into the surrounding soil will not produce any pollution of the latter. The best material for drains is porous earthenware pipe, or the ordinary agricultural drain-tile. Coarse gravel or broken stones may also be used, and prove efficient if the drains are properly constructed. Referring again to the aphorism of Professor DeChaumont, that a persistently low ground-water, say 5 metres down, or more, is healthy; that a persistently high ground-water, less than 1 1 metres from the surface is unhealthy ; and' that a fluctuating level, especially if the changes are sudden and violent, is very unhealthy, the necessity appears obvious that in the construction of drainage-works the drains should be placed at a sufficient depth to secure a level of the ground-water consistent with health. This depth should never be less than 3 metres, and, if possible, not less than 5 metres. Care must be taken that the outflow of the drain is unobstructed, in order that the soil may be kept properly dry at all times. In the absence of a proper mechanical system of drainage, the planting of certain trees may efficiently drain the soil. It has been found that the eucalyptus tree has produced drying of the soil when planted in sufficient numbers in marshy land. The roots absorb a prodigious quantity of water, which is then given off by evaporation from the leaves. Sunflower-plants have a similar effect upon wet soils. QUESTIONS TO CHAPTER IV. THE SOIL. Why is it necessary to possess a knowledge of the physical and chemical conditions of the soil ? What substances are included in the consideration of soils ? Of what is the surface soil composed ? How do soils vary in composition, physically and chemically ? What occupies the interstices of the soil ? Upon what does the proportion of air in the soil depend ? Is this proportion comparatively great or small? What relation has the soil-air to the atmospheric air, and what causes the difference in composition ? In what way does the soil-air differ from the atmospheric air ? Has the soil-air an}' definite composition ? What are the factors governing the variation in composi- tion ? What kind of a soil will be likely to contain most carbon dioxide and least oxygen ? What does this indicate ? What micro-organisms are always to be found in the soil-air? What pathogenic organisms may also make the soil and soil-air their habitat ? How may these be carried from place to place ? To what are movements of the ground-air due? How may this soil-air gain access to our houses, and what meas- ures should be taken to prevent its entrance? When is the danger greatest ? Why are certain infectious diseases less prevalent in spring and early summer than in autumn? Why is there greater danger of infection from these diseases at night than in the day -time? Is the carbon dioxide of the soil-air a measure of the impurity of the soil ? What causes the excess of carbon dioxide ? When is the proportion of carbon dioxide greatest? Why are living-apartments below the surface 01 the ground very apt to be unhealthy ? What is meant by the term "ground-water"? Where is it to be found? Has it a definite current? In what direction is the flow? Upon what does the level of the ground-water depend ? What class of the population derive their drinking-water largely from the ground- water ? What are some of the sources of contamination of the ground- water ? What are some of the deductions to be made accordingly ? In what part of the soil do the processes of organic decay and putre- faction occur most readily? What are the causes of these processes? What are some of their products? What is the distinction between non-putrefactive decomposition or deca}- and putrefaction ? 10 (145) 146 QUESTIONS TO CHAPTER IV. How m&y disease be spread by the rise and fall of the ground-water? What two infective diseases are especially apt to be transmitted in this way? Give instances that tend to prove this. Upon what other dis- ease has a damp soil a directly causative influence ? What diseases of animals are likely to be influenced in a similar manner? How deep below the surface should the soil-water persistently be that the soil may be healthy ? What effect upon health has a suddenly and markedly fluctuating soil-water ? Is a soil with its water persistently near the surface apt to be health}' ? What do we mean by drainage, and what is its object and function ? What is the difference between it and sewerage? How should drains be laid ? What is the best material for drains ? What precautions must be observed in the laying of drains? How may the surplus water be taken from the soil otherwise than by drains ? CHAPTER V. REMOVAL OF SEWAGE. IN all larger communities certain arrangements are neces- sary to secure a prompt and efficient removal of excreta and the refuse and used water of households and manufacturing establishments, the sweepings of streets, and rain-water. The total quantity of excrementitious products faeces and urine for each individual, including men, women, and children, has been estimated by Professor von Pettenkofer as 90 grammes of faecal and 1170 grammes of urinary discharge daily. This would give for a population of 1000 persons 34,000 kilogrammes of faeces and 428,000 litres of urine per year. If to this is added a minimum allowance of 159 litres of water per day to each individual, a complete sewerage system for a population of 1000 persons would require provision for the discharge of 160,000 litres of sewage passing through the sewers every day. In this estimate storm-water and such accessory feeders of the sewage are omitted. The organic matters contained in sewage, even if free from the specific germs of disease, give rise to noxious emanations, which, when inhaled, probably produce a gradual depravement of nutrition that renders the system an easier prey to disease. For this and other reasons it is important that such measures be adopted as will secure the removal of sewage matters from the immediate vicinage of houses as quickly as possible after they have been discharged. The impregnation of the soil with sewage produces a con- tamination of ground-air and ground-water, which may become a source of grave danger to health. By polluting the ground- water it eventually vitiates the well-water, which is nearly always derived from that source. (147) 148 TEXT-BOOK OF HYGIENE. The system of removal of excrementitious matters which any community will adopt depends to a considerable extent upon financial considerations. Although the sanitarian must insist upon the pre-eminent importance of the cause of public health, his suggestions will receive little attention from municipal or state legislatures unless they can be carried out without involv- ing the community too deeply in debt. For this reason it is a matter of great practical importance that the student of sani- tary science should make himself familiar with the relative cost as well as with the hygienic significance of the various methods of sewage removal in use. The different systems in use for the removal of sewage matters may be considered in detail under the following five heads: 1. The common privy, or privy- vault systems. 2. The Rochdale or pail system, and its modifications. 3. The earth- or ash- closet system. 4. The pneumatic system of Liernur. 5. The water-carriage systems. 1. The Privy and Privy-well Systems. While from a sanitary point of view privies of all kinds, whether wells or cess-pits, are to be unreservedly condemned, it is not likely that they will cease to be built for many years to come. It becomes necessary, therefore, to point out by what means the objections against them may be diminished, and their evil consequences in some measure averted. In the first place, a privy- vault should be perfectly water- tight in order to prevent pollution of the surrounding soil by transudation of the contained excremental matters. The walls should be of hard-burned brick laid in cement. The cavity should be small in order that the contents may be frequently re- moved, and not allowed to remain and putrefy for months or years. A water-tight hogshead sunk in the ground makes an economical privy-tank or receiver. A privy must not be dug in a cellar, or in too close proximity to the house-walls. Unless REMOVAL OF SEWAGE. 149 these last precautions are taken the offensive gases from the mass of decomposing faecal matter in the privy will constantly ascend into and permeate the air of the house. All privies should be ventilated by a pipe passing from just under the privy-seat to a height of about a metre above the roof of the house. A gas-flame, kept burning in the upper portion of this pipe, will increase its ventilating power by creating a strong and constant upward current. Deodorization of the contents of privies may be secured in a measure by means of sulphate of iron, phenyle, carbolic acid, or dry earth. The first named is probably the most economical, most easily applied, and very effective. A solution containing from | to 1 kilogramme of the salt in 4 litres of water is poured into the privy as often as necessary to prevent offensive odors. This solution may be conveniently prepared by suspending a basket or bag containing about 25 kilogrammes of the sulphate in a barrel of water. In this way a saturated solution will be maintained until the salt has been entirely dissolved. Phenyle is likewise a good deodorizer as well as an excellent disinfectant. The most rigid deodorization by chemicals will, however, be less effective than thorough ventilation, for it must be re- membered that the mere destruction of an offensive odor is not equivalent to removing all the deleterious properties that may be present. It is not at all certain that those elements of sew- age which are the most offensive to the sense of smell are most detrimental to health. Privies should be emptied of their contents at stated inter- vals. A strict supervision should be exercised over them by the municipal authorities in cities and towns to prevent overflowing of their contents. In many places the method of removing the contents of privies is the primitive one with shovel, or dipper and bucket. In most cities and large towns, however, the privy-vaults or tanks are now emptied by means of one of the so-called odorless excavat- ing machines, of which there are a number of different patents. 150 TEXT-BOOK OF HYGIENE. The process is rarely entirely odorless, however, as the careless- ness of the workmen frequently permits offensive gases to escape and pollute the air for a considerable distance. All the different forms of the apparatus act upon the pneumatic principle. One end of a large tube is carried into the cess-pool or vault to be emptied and the other attached to a pump, by means of which the material is pumped into a strong barrel-tank carried on wheels. At the top of the tank is a vent, over which is placed a small charcoal furnace to consume the foul gases escaping from the vent. In some cities and many of the smaller towns and villages in this country the primitive midden or pit system is still in use. A shallow pit is dug in the ground, over which is erected the privy. When the pit is full another is dug close by the side of it, and the earth from the new pit thrown upon the excrement in the old one. The privy is then moved over the new pit, and this is used until it too becomes full. The proceeding is re- peated as often as the pit becomes filled up with the excreta, until in the course of a few years all the available space in a yard has been honey-combed with the pits. Then the custom adopted in overcrowded cemeteries is followed, namely, the first pit is dug out again and the cycle is repeated. In other cities the privy-well system is largely in use. This is next to the midden or shallow pit just described the most pernicious system for the disposal of excreta that can be imagined. The wells are dug to such a depth as to reach the subterranean now of water, in which the soluble excremental matters are constantly carried off. Hence these receptacles rarely fill up or need cleaning. For this reason they are popular with property owners ; for, next to the primitive midden, they are the most economical of all the various methods adopted. The utter pemiciousness of the system is, however, plain, because the soil for a considerable distance around each of these wells becomes a mass of putrid filth, contaminating the ground-water which feeds the drinking- water supplies in the vicinity ; polluting also REMOVAL OF SEWAGE. 151 the ground-air, which eventually reaches the surface, or the in- terior of houses, when the pressure of the outside atmosphere diminishes or the ground-water level rises. It must, therefore, be evident that the best ventilating arrangements, or the most thorough and consistent disinfection, can have very little, if any, effect in removing the very grave objections to this baneful system. The privy-well system for the removal of excreta cannot be recommended for adoption by any sanitarian. 2. The Rochdale, or Pail-closet System. The Rochdale system of removal of excreta has won the support of many dis- tinguished sanitarians on account of its simplicity, its economy, and its compliance with most sanitary requirements. The ex- creta, both solid and liquid, are received into a water-tight pail, either of wood or metal, and removed once or oftener a week, a clean and disinfected pail being substituted for the one removed. In Rochdale, Manchester, and Glasgow in Great Britain, in Heidelberg in Germany, and in other cities abroad, where this system has been introduced, it has worked satisfac- torily. In this country a modification of the pail system, known as the Eagle Sanitary Closet, has been introduced by a firm in Charleston, S. C. The receptacle consists of an enameled-iron reservoir, with a neck just large enough to fit under the seat of the privy, and a quantity of disinfectant solution is put into the receptacle to prevent putrefaction of the excreta. The recep- tacles are replaced by clean ones every week. Mr. James T. Gardner, Director of the New York State Sanitary Survey, says, in a special report on methods of sewerage applicable in small towns and villages, concerning the pail system 1 : " Rochdale is a city of some 70,000, and Manchester of between 400,000 and 500,000 inhabitants. The higher class of houses are allowed to have water-closets, but four-fifths of the people are obliged to have ' pail-closets ' in their yards built 1 Second Annual Report of New York State Board of Health, pp. 322, 323. 152 TEXT-BOOK OF HYGIENE. according to plans of the Health Department. Their essential features are : A flag-stone floor, raised a few inches above the level of the yard ; a hinged seat, with a metal rim underneath for directing urine into the pail, which stands on the flag directly beneath the seat ; a hinged front and back to the seat, so that the pail or tub may be easily taken out and the place cleaned ; and a 6-inch ventilating pipe from under the seat to above the roof. In Rochdale they use a wooden pail or tub made of half of a disused paraffine cask, holding about 40 kilogrammes ; in Manchester the ' pail ' is of galvanized iron and holds 40 litres. Under the direction of the authorities, they are removed once a week in covered vans, which bring clean tubs to be put in the place of the full ones taken away. Each tub is covered with a close-fitting double lid before removal. The tubs are taken to a depot, where their contents are deodorized and prepared as manure by mixing with ashes and a small proportion of gypsum to fix the ammonia. Subsequently, street-sweepings and the refuse of slaughter-houses are added. At Manchester there is by the side of each closet a very simple ash-sifter, from which the ashes fall into the tub and help to deodorize its contents. " The manure at Rochdale sells for about four-fifths of the cost of the collection and preparation. " In 1873 the net cost to the town of removing and dispos- ing of the house dry refuse and excrement was only about $95 per annum per 1000 of population, less than 10*cents a person per annum. " The system has been in operation more than twelve years. " The tubs are removed in the day-time without offensive odor! " Where ashes are frequently thrown into the tubs at Man- chester, very little odor is to be perceived in the closets. " For the villages of the State, which can have no general water-supply, I would unhesitatingly advise the use of the ' pail ' or tub system as practiced in Manchester, England, as being, from a sanitary point of view, an immense improvement REMOVAL OF SEWAGE. 153 over the death-breeding privy-vaults in common use. The cheapness of the plan and the small ness of the original outlay of brains and money, in comparison with that needed to build a good sewer system, will make it possible to introduce a tub- privy system into most villages half a century before sewers would meet with any consideration. " At a small cost the existing privy- vaults can be cleaned and filled, and the privies altered into healthful tub-closets. The town authorities must then arrange for the removal of the tubs once a week, and for their thorough cleansing and disinfecting. Any isolated house, or group of houses, can use the tub system, taking care of it themselves. If the plan is adopted in villages it will doubtless spread into the country, and become the most powerful means of abolishing the fatal privy-vaults which are poisoning the farm-wells." 3. Earth- and Ash- Closets. The earth- and ash- closets are devices in use to a large extent in England, and to a less degree in this country, for the purpose of rendering human ex- creta inodorous by covering them immediately after they are voided with dry earth or ashes. The earth-closet is the inven- tion of the Rev. Henry Moule, of England, and consists of an ordinary commode or closet, the essential feature of which is a reservoir containing dried earth or ashes, a quantity of which, amounting to about twice the quantity of fasces voided, is thrown upon the evacuation either by hand or by means of an auto- matic apparatus called a "chucker." Just as in the ordinary water-closet, by raising a handle a supply of water is thrown into the hopper to wash down the faeces into the soil-pipe, so, in the usual form of the earth-closet, raising the handle projects a quantity of earth upon the evacuated faeces and urine. By this means the excreta are rendered entirely inodorous and dry. The contents of the closets may be collected into a heap in a dry place. In the course of a few months the organic constit- uents have become oxidized, and the earth may be used over again for a number of times. A well-known sanitarian states 154 TEXT-BOOK OF HYGIENE. that he has used sifted anthracite coal-ashes ten or twelve times over in the course of three years. During this time the material under no circumstances gave any indication that it was " any- thing but ashes, with a slight admixture of garden soil." 1 ' Dr. Buchanan, of England, comparing the advantages of the earth-closet with those of the water-closet, says: "It is cheaper in original cost ; it requires less repairs ; it is not in- jured by frost ; it is not damaged by improper substances being FIG. 4. PULL-UP HANDLE COMMODE, SHOWING THE DOOR OPEN FOR' REMOV- ING PAIL. THE FLAP OF THE SEAT AND EARTH-RESERVOIR ARE ALSO PAR- TIALLY RAISED TO SHOW THE CON- STRUCTION. FIG. 5. S HOAVING THE APPARATUS MOUNTED ON BEARERS AS WHEN FIXED. SEAT REMOVED, SHOWING ME- CHANICAL ARRANGEMENT. thrown down it ; and it very greatly reduces the quantity of water required by each household." 2 In cities and towns the removal of the excreta should be carried out by or under the immediate direction of the mu- nicipal sanitary authorities. If this is neglected, abuses are liable to creep in which will vitiate the performance of any system, however faultless, when properly managed. Many advocates of the pail, dry earth, or privy systems urge the advantage of the large quantity of valuable manure which 1 The Sanitary Drainage of Houses and Towns, Waring, p. 250. 2d ed., 1881. 2 Quoted in Waring, above cited, p. 264. REMOVAL OF SEWAGE. 155 can be realized by converting the excremental matters into pou- drette and other fertilizing compounds. Experience has shown, however, that the cost of preparing a satisfactory fertilizer from human excrement is much greater than can be realized from its sale. In all places in Great Britain and the continent of Europe where it has been tried the decision is against its practicability. The agricultural consideration should, however, be a secondary one, if the systems mentioned are economical and meet the sanitary requirements (which the privy system certainly does not). The adoption of one or other of them may be secured where more perfect but more complicated and expensive systems may be out of the question. 4. The Pneumatic System of Liernur. A system which seems to be useful in larger cities, especially where the topo- graphical conditions are such as to render necessary mechanical aid in overcoming obstacles to natural drainage, is the pneu- matic system devised by Captain Liemur, of Holland, and generally known as the Liernur system. It consists of a set of soil-pipes running from the water-closets to central district reservoirs, from which the air is exhausted at stated intervals. When a vacuum is created in the reservoir the contents of the water-closets and soil-pipes are driven forcibly into the reservoir by the pressure of air. The district reservoirs are connected by a separate system of pipes with a main depot, and the transfer of the faBcal matter from the former to the latter is also accom- plished with the aid of pneumatic pressure. The complete system of Liernur provides that at the main depot the faecal matter shall be treated with chemicals, evaporated, and con- verted into a dry fertilizer poudrette. It appears from the published reports that while the system has been partially adopted in three Dutch cities, in only one of them, Dortrecht, has the machinery for manufacturing poudrette been established. AVith reference to this Erismaim 1 says: "It seems never to have 1 Yon Pettenkofer und Ziemssen : Handbuch tier Hygiene. II Th., II Abth., 1 Hefte, p. 140. 156 TEXT-BOOK OF HYGIENE. been in regular working order, for the faecal masses are mixed with street-sweepings and ashes into a compost-mass, which causes no little discomfort in the neighborhood by the offensive odors. In Amsterdam the faecal matters, which frequently do not find a ready sale, are partly made into a compost with sweepings, partly used to fertilize meadows, or simply discharged into the water." As to the practical working of the system the opinions differ widely. While the majority of sanitarians, including Virchow, von Pettenkofer, and Mr. Rawlinson, object to it as not fulfilling the demands of hygiene, the system has also been criticized by engineers as not being in accordance with the well- known principles of their science. 1 Two other plans for the removal of faecal matter by pneu- matic pressure have been invented, namely, the Shone and the Berlier systems. Neither of these has been adopted to any considerable extent. Both seem to the author to fall far short even of the merits of the Liernur system. 5. The Water- Carriage System of Seiverage. Two sys- tems of removal of sewage by water-carriage are in use at the present time. They are technically known as the " combined " and the " separate " systems. In the former, which is the sys- tem upon which the most of the sewers in this country are constructed, all excreta, kitchen-slops, waste-water from baths and manufacturing establishments, as well as storm-water, are carried off in the same conduits. In the separate system, on the other hand, the removal of the storm-water is provided for, either by surface or under-ground drains, not connected with the sewers proper, in which only the discharge from water-closets and the refuse-water from houses and factories are conveyed. In the separate system the pipes are of such small calibre that a constant flow of their contents is maintained, preventing 1 Papers by Maj. C. H. Latrobe and Col. Geo. E. Waring, Jr., in Fifth Biennial Report Md. State Board of Health. See also, in favor of system, a paper by Dr. C. W. Chancellor, in same publication, and an elaborate description by the same author in Trans. Med. and Chir. Faculty of Md., 1883. REMOVAL OF SEWAGE. 157 deposition of suspended matters and diminishing decomposition and the formation of sewer-gas. In the combined system, on the other hand, the sewers must be made large enough to receive the maximum rain-fall of the district. This requires a calibre greatly in excess of the ordinary needs of the sewer, and furnishes favorable conditions for the formation of sewer-gas and the development of minute vegetable organisms. The ordinary flow in a sewer of large calibre is usually so sluggish as to promote the deposition of solid matters and the gradual obstruction of the sewer. It is the opinion of the most advanced sanitarians that the separate system fulfills the demands of a rational system of sewerage better than any other at present in use. The objec- tions to the combined system are so many and so great that it does not seem advisable for sanitary authorities to recommend the construction of sewers on this principle in the future. The separate system of sewerage, indorsed as it is by high engineering and sanitary authorities, and by a satisfactory, prac- tical test of twelve years in the city of Memphis and of nine years in the town of Keene, N. H., seems to the author to possess merits above any other plan for the removal of excreta and house-wastes. The following description is from a paper by Col. George E. Waring, Jr.: U A perfect system of sanitary sewerage would be something like the following: No sewer should be used of a smaller diameter than 6 inches (15 centi- metres) : a, because it will not be safe to adopt a smaller size than 4-inch (10 centimetres) for house-drains, and the sewer must be large enough to surely remove whatever may be de- livered by these; b, because a smaller pipe than 6-inch would be less readily ventilated than is desirable ; c, and because it is not necessary to adopt a smaller radius than 3 inches (5 centi- metres) to secure a cleansing of the channel by reasonably copious flushing. "No sewer should be more than 6 inches (15 centimetres) hi diameter, until it and its branches have accumulated a 158 TEXT-BOOK OF HYGIENE. sufficient flow at the hour of greatest use to fill this size half full, because the use of a larger size would be wasteful, and because when a sufficient ventilating capacity is secured, as it is in the use of a 6-inch pipe, the ventilation becomes less complete as the size increases, leaving a larger volume of contained air to be moved by the friction of the current, or by extraneous in- fluences, or to be acted upon by changes of temperature and of volume of flow within the sewer. "The size should be increased gradually, and only so rapidly as is made necessary by the filling of the sewer half full at the hour of greatest flow. " Every point of the sewer should, by the use of gaskets or otherwise, be protected against the least intrusion of cement, which, in spite of the greatest care, creates a roughness that is liable to accumulate obstructions. " The upper end of each branch sewer should be provided with a Field's flush-tank of sufficient capacity to secure the thorough daily cleansing of so much of the conduit as from its limited flow is liable to deposit solid matters by the way. " There should be sufficient man-holes, covered by open gratings, to admit air for ventilation. If the directions already given are adhered to, man-holes will not be necessary for cleans- ing. The use of the flush-tank will be a safeguard against deposit. With the system of ventilation about to be described, it will suffice to place the man-holes at intervals of not less than 1000 feet (305 metres). " For the complete ventilation of the sewers it should be made compulsory for every householder to make his connection without a trap, and to continue his soil-pipe above the roof of his house. That is, every house connection should furnish an uninter- rupted ventilation-channel 4 inches (10 centimetres) in diameter throughout its entire length. This is directly the reverse of the system of connection that should be adopted in the case of storm-water and street-wash sewers. These are foul, and the volume of their contained air is too great to be thoroughly ven- REMOVAL OF SEWAGE. 159 tilated by such appliances. Their atmosphere contains too much of the impure gases to make it prudent to discharge it through house-drains and soil-pipes. With the system of small pipes now described, the flushing would be so constant and complete and the amount of ventilation furnished, as compared to volume of air to be changed, would be so great, that what is popularly known as ' sewer-gas ' would never exist in any part of the public drains. Even the gases produced in the traps and pipes of the house itself would be amply rectified, diluted, and removed by the constant movement of air through the latter. "All house connections with the sewers should be through inlets entering in the direction of the flow, and these inlets should be funnel-shaped so that their flow may be delivered at the bottom of the sewer, and so that they may withdraw the air from its crown; that is, the vertical diameter of the inlet at its point of junction should be the same as the diameter of the sewer. " All changes of direction should be on gradual curves, and, as a matter of course, the fall from the head of each branch to the outlet should be continuous. Reduction of grade within this limit, if considerable, should always be gradual. "So far as circumstances will allow, the drains should be brought together, and they should finally discharge through one or a few main outlets. " The outlet, if water-locked, should have ample means for the admission of fresh air. If open, the mouth should be pro- tected against the direct action of the wind. " It will be seen that the system of sewerage here described is radically different from the usual practice. It is cleaner, is much more completely ventilated, and is more exactly suited to the work to be performed. It obviates the filthy accumulation of street-manure in catch-basins and sewers, and.it discharges all that is delivered to it at the point of ultimate outlet outside the town before decomposition can even begin. If the discharge is of domestic sewage only, its solid matter will be consumed by 160 TEXT-BOOK OF HYGIENE. fishes if it is delivered into a water-course, and its dissolved material will be taken up by aquatic vegetation. " The limited quantity . and the uniform volume of the sewage, together with the absence of dilution by rain-fall, will make its disposal by agricultural or chemical processes easy and reliable. "The cost of construction, as compared with that of the most restricted storm-water sewers, will be so small as to bring the improvement within the reach of the smaller communities. "In other words, while the system is the best for large cities, it is the only one that can be afforded in the case of small towns. " Circumstances are occasionally such as to require extensive engineering works for the removal of storm-water through very deep channels. Ordinarily, the removal of storm- water is a very simple matter, if we will accept the fact that it is best carried, so far as possible, by surface gutters, or, in certain cases, by special conduits, placed near the surface. " It is often necessary, in addition to the removal of house- waste, to provide for the drainage of the subsoil. This should not be effected by open joints in the sewers; because the same opening that admits soil-water may, in dry seasons and porous soils, permit the escape of sewage matters into the ground, which is always objectionable. " Soil- water drains may be laid in the same trench with the sewers, but preferably, unless they have an independent outlet, on a shelf at a higher level. When they discharge into the sewer they should always deliver into its upper part, or into a man-hole at a point above the flow-line of the sewage." 1 The establishment of a system of sewerage presupposes a constant and abundant supply of water to keep all closets clean and all house-drains and street-sewers well flushed. Where this cannot be obtained, sewers would be likely to prove greater evils than benefits. In such cases one of the methods of removal 1 The Sewering and Drainage of Cities, Waring, Public Health, vol. v, p. 35. REMOVAL OF SEWAGE. 161 of excreta before mentioned, either the pail- or earth- closet system, should be adopted. The final disposal of sewage is a problem that depends for its solution partly upon the agricultural needs of the country around the city to be sewered, partly upon the proximity of large bodies of water or running streams. When the city is situated upon or near large and swiftly-flowing streams, the sewage may be emptied directly into the stream without seriously impairing the purity of the latter, although the principle of thus disposing of sewage is wrong. Dilution, deposition, and oxida- tion will soon remove all appreciable traces of the sewage of even the largest cities. Where, on the other hand, the stream is inadequate in size to carry off the sewage, or where, as in the Seine and Thames, the current is sluggish, some other method of final disposal must be adopted. In many cities of Great Britain and the continent of Europe the disposal of the sewage by irrigation of cultivated land has been practiced for a number of years. The reports upon the working of the system are generally favorable, although some sanitarians express doubts of the efficiency of the system. In using sewage for the irrigation of land, two objects are secured : first, the fertilization of the land by the manurial constituents of the sewage, and, second, the purification of the liquid portion by filtration through the soil. The organic matters which have been held back by the soil undergo rapid oxidation in the presence of air and the bacteria of decay, and are converted into plant- food, or into harmless compounds. Sewage irrigation, as prac- ticed in Europe, must make provision for the disposal of a very large proportion of water in the sewage (street-wash, storm- water), which requires much larger areas of land than would be needed if only sewage material proper (water-closet and kitchen- waste) was to be thus disposed of. In this country a practical experiment has recently been. made at Pullman, Illinois, delivering only the sewage materials above mentioned upon the irrigation area. The success of the experiment is said to be satisfactory. 11 162 TEXT-BOOK OF HYGIENE. All land used for sewage irrigation should be drained with drain- tile at a depth of 3 to 6 feet (1 to 2 metres) below the surface, in order to promote a rapid carrying off of the watery portion of the sewage, purified by filtration through the soil. A sandy loam is the best soil for irrigation. Clay is not sufficiently permeable to air and water, while pure sand allows the sewage to pass through too readily, before the organic matters in it have been sufficiently oxidized. It has been shown that the roots of plants assist largely in the oxidation of organic matter. The entire process of collecting and finally disposing of sewage matters, from the moment they are received in the house- receptacles until discharged into the swiftly-flowing stream or on the sewage farm, should be void of offense to the senses of sight or smell. With a proper construction and management of sewerage works, on the hues indicated in this chapter, it is believed these results can be attained. During the past five or six years a number of experi- ments have been made in this country with various processes for the disposal of excreta and garbage by cremation. In a general way the principle may be pronounced a success, although its proper application in practice is still under discussion. [The following works give fuller details upon the matters treated in the two foregoing chapters: Erismann, Entfernung der Abfallstoffe. Hdbch. d. Hygiene, etc., II Tli., I Abth., 1 Hlfte. C. F. Folsoin, Seventh Report Mass. State Board of Health, 1876, p. 276. Soyka, Stadte-reinigung, in Realency- clopsedie d. ges. Heilk.,Bd. xiii, p. 14 et seq. Pettenkofer, The Sanitary Relations of the Soil, in Pop. Sci. Monthly, vol. xx, pp. 332, 468. Cor- tield and Parkes, The Treatment and Utilization of Sewage, 1887. Re- ports of the Committee on Destruction of Garbage and Refuse, Public Health, vols. xiv and xv. Soyka, Der Boden in Hdbch. d. Hygiene, I Thl., 2 Abth., 3 Heft. W. Santd Crimp, Sewage-Disposal Works. Waring, Modern Methods of Sewage Disposal.] QUESTIONS TO CHAPTER V. REMOVAL OF SEWAGE. Why must arrangements be made in all large communities for the removal of sewage ? To what do the organic constituents of sewage give rise, and what is the effect upon health of the continued inhalation of these products ? How else may the impregnation of the soil with sewage endanger health ? What, then, is the object of any system of sewage removal ? What will likely govern the choice and adoption of a sewage-removal system by an}- community ? What different systems are in use at the present time? Which of these is the worst and most unsanitary ? In case the privy system is to be considered, what conditions should be insisted upon ? How may a privy be ventilated ? Why should a privy not be located in a cellar nor too near the house? What substances may be used to deodorize the contents of privy-vaults, and how ? Are deodorizers always disinfect- ants, and is the danger necessarily removed when the odor is destroyed? How often should privy-vaults be emptied? How may this be done without offense to the senses ? What are the grave objections to the midden or shallow-pit system, and to digging the vault or cess-pool to the level of the ground-water ? What is meant by the Rochdale or pail-closet system ? What are some of its advantages ? What can be said of its efficacy for large com- munities and for the economy of administration ? What is an earth- closet, and upon what does its efficacy depend ? What are some of its advantages ? Describe the pneumatic system of Liernur. Has it apparently been satisfactory in its workings ? What other systems have employed the pneumatic principle, and with what success ? What do we mean by the water-carriage system of sewerage ? What two systems are embraced under this head ? What is the distinction between the two ? Which is in most common use ? What must be the size of the sewers in the combined system, and what are the consequent objections ? Why does the separate system seem the better ? Describe the latter in detail. What governs the size of the drains in the separate system ? How is this system kept clean and free from obstructions ? How is it to be ventilated ? How does it differ in this respect from the combined system ? What are some of the especial points to be observed (163) 164 QUESTIONS TO CHAPTER V. in the construction ? What may be said as to cost of construction and as to the ultimate disposal of the sewage ? Why should sewers not be empktyed to drain the subsoil? How may this be done? What does the establishment of a sewerage system presuppose? If plenty of water cannot be had, what system of sewage removal should be adopted ? In what way may we finally dispose of the sewage ? What are the objections to discharging it into running streams ? How will it be finally disposed of in such a stream? What is meant by the irrigation, the sub-irrigation, and the filtration methods ? What becomes of the organic matter of the sewage in each case? What of the sewage water ? What sort of soil is needed for the irrigation method? What can be said of the disposal of sewage and garbage by cremation ? CHAPTER VI. CONSTRUCTION OF HABITATIONS. THE importance of observing the principles of hygiene in the construction of habitations for human beings is not suffi- ciently appreciated by the public. Architects and builders them- selves have not kept pace with the sanitarian in the study of the conditions necessary to be observed in building a dwelling-house which shall answer the requirements of sanitary science. In an investigation conducted by Dr. Villerme 1 it was found that in France, from 1821 to 1827, of the inhabitants of arron- dissements containing 7 per cent, of badly-constructed dwellings, 1 person out of every 72 died ; of inhabitants of arrondissements containing 22 per cent, of badly-constructed dwellings, 1 out of 65 died ; while of the inhabitants of arrondissements containing 38 per cent, of badly-constructed dwellings, 1 out of every 45 died. Inseparable from the question of the defective construction of dwellings is that of overcrowding in cities, because the most crowded portions of a city are at the same time those in which the construction of dwellings is most defective from a hygienic stand-point. The following tables show the relations of the death-rate to density of population in various large cities of Europe, and also the relations between overcrowding in dwell- ings and the mortality from contagious diseases : TABLE XVII. RELATION OF DEATH-RATE TO DENSITY OF POPULATION. CITY. Mean Number of Inhab- itants to each House. Average Death-rate per 1000 Inhabitants. 8 24 32 25 35 28 52 41 55 47 1 Quoted in Realeucyclopaedia d. ges. Heilk, Bd. ii, 71. (165) 166 TEXT-BOOK OF HYGIENE. In Glasgow, the death-rate in apartments with 1.31 occu- pants is 21.7 per 1000, while in apartments with 2.05 occupants the rate is 28.6 per 1000. In Buda-Pesth, in 1872-73, it was found that out of every 100 deaths from all causes there were, from contagious diseases : 20 deaths in dwellings with 1 to 2 persons in each room. .)() .. - " " 3 5 << " " " qo 6 10 " " " 79 " " " " over 10 " " " " Dr. Jose A. de los Rios gives the following statistics, bear- ing upon the mortality of cholera, in relation to the number of persons occupying one room when attacked by it : Of 10,000 persons attacked by cholera, and living 1 person to the room, 68 died. Of 10,000 persons attacked by cholera, from 1 to 2 to the room, 131 died. Of 10,000 persons attacked by cholera, living 2 to 4 to the room, 219 died. Of 10,000 persons attacked by cholera, living 4 or more to the room, 327 died. These figures show very clearly the vital importance of the application of sanitary laws in the construction and occupation of dwellings. Another curious and suggestive point is presented by some statistical researches on the mortality of Berlin, in regard to the death-rate among persons living in different stories of houses. It was found, for example, that the mortality in fourth-story dwell- ings is higher than in the lower stories. Even basement dwell- ings furnish a lower death-rate. Still-births, especially, occur in a larger proportion among the occupants of the upper stories of houses. This may be explained by the unfavorable effects of frequent stair-climbing, especially in pregnant women. It is in the death-rate among young children that the effects of overcrowding and unsanitary construction of dwellings are especially manifest. The mortality returns from all the large CONSTRUCTION OF HABITATIONS. 167 cities of the world give mournful evidences of this every summer. The researches of Dr. H. I. Bowditch upon soil- wetness, to which reference has already been made in a previous chapter, show conclusively that persons living in houses situated upon or near land habitually or excessively wet, are especially prone to be attacked by pulmonary consumption. Dr. Buchanan 1 has corroborated the truth of Dr. Bowditch's observations by show- ing, from the records of a number of cities and towns of Great Britain, that, with the introduction of a good drainage system, bringing about a depression and uniformity of level of the ground-water, the mortality from consumption and other dis- eases very markedly diminished. The following table, showing the proportionate amount of this diminution, is abridged from the official reports 2 : TABLE XVIII. RESULTS OF SANITARY WORK. NAME OF PLACE. Population m 1861. Average Mortality per 1000 before Construction of .Works. Average Mortality per 1000 since Com- pletion of Works. Saving of Life (percent.). Reduc- tion of Typhoid Fever Rate (per cent. ) . Reduc- tion in Rate of Phthisis (percent.). Banbury 10,238 23.4 20.5 12* 48 41 Cardiff . 32,954 33.2 22.6 32 40 17 Croydon 30,229 23.7 18.6 22 63 17 Dover ' . 23,108 22.0 20.9 7 36 20 Ely . . 7,847 23.9 20.5 14 56 47 Leicester 68,056 26.4 25.2 *i 48 32 Macclesfield 27,475 29.8 23.7 20 48 31 Merthyr 52,778 33.2 26.2 18 60 11 Newport 24,756 31.8 21.6 32 36 32 Rugby . 7,818 19.1 18.6 2* 10 43 Salisbury 9,030 27.5 21.9 20 75 49 Warwick 10,570 22.7 21.0 7* 52 19 The following points must be taken into account in building a house in accordance with sanitary principles : i. SITE. The building-site should be protected against violent winds, although a free circulation of air all around the house 1 Ninth and Tenth Reports of the medical officer to the Privy Council. 1 Sanitary Engineering, Baldwin Latham, p. 2. Chicago, 1877. 168 TEXT-BOOK OF HYGIENE. must be secured. Close proximity to cemeteries, marshes, and injurious manufacturing establishments or industries must be avoided if possible. A requisite of the highest importance is the ability to command an abundant supply of pure water for drinking and other purposes. A neglect of this precaution will be sure to result to the serious inconvenience, if not detriment, of the occupants of the house. II. CHARACTER OF THE SOIL. The soil should be porous and free from decomposing ani- mal or vegetable remains, or excreta of man or animals. It should be freely permeable to air and water, and the highest level of the ground-water should never approach nearer than 3 metres to the surface. The fluctuations of the ground-water level should be limited. In this connection, attention is again called to the aphorism of Dr. DeChaumont. l It is impossible to say positively that any kind of soil is either healthy or unhealthy, merely from a knowledge of its geological characters. The accidental modifying conditions above referred to, viz., organic impurities, moisture, the level and fluctuations of the ground-water, are of much greater importance than mere geological formation. The late Dr. Parkes, however, regarded the geological structure and conforma- tion as of no little importance, and summarized the sanitary relations of soils, variously constituted, as follows 2 : "1. The Granitic, MetamorpJi fr. < i,i< / Trap Rock*. Sites on these formations are usually healthy ; the slope is^-reat, water runs off readily; the air is comparatively dry; vegetation is not excessive; marshes and malaria are comparatively infrequent; and few impurities pass into the drinking-water. "When these rocks have been weathered and disintegrated they are supposed to be unhealthy. Such soil is absorbent of water; and the disintegrated granite of Hong Kong is said to 1 Chapter iv, p. 130. ' Practical Hygiene, 6th ed., vol. i, p. 359. CHARACTER OF THE SOIL. 169 be rapidly permeated by a fungus; but evidence as to the effect of disintegrated granite or trap is really wanting. "In Brazil the syenite becomes coated with a dark sub- stance and looks like plumbago, and the Indians believe this gives rise to 'calentura,' or fevers. The dark granitoid, or metamorphic trap, or hornblendic rocks in Mysore, are also said to cause periodic fevers; and iron hornblende, especially, was affirmed by Dr. Heyne, of Madras, to be dangerous in this respect. But the observations of Bichter on similar rocks in Saxony, and the fact that stations on the lower spurs of the Himalayas on such rocks are quite healthy, negative Heyne's opinion. " 2. The Clay Slate. These rocks precisely resemble the granite and granitoid formations in their effect on health. They have usually much slope, are very impermeable, vegetation is scanty, and nothing is added to air or drinking-water. "They are consequently healthy. Water, however, is often scarce, and as to the granite districts, there are swollen brooks during rain, and dry water-courses at other times swelling rapidly after rains. " 3. The Limestone and Magnesian Limestone Roclcs. These so far resemble the former that there is a good deal of slope and rapid passing off of water. Marshes, however, are more common, and may exist at great heights. In that case, the marsh is probably fed with water from some of the large cavities which in the course of ages become hollowed out in the limestone rocks by the carbonic acid in the rain, and form reservoirs of water. "The drinking-water is hard, sparkling, and clear. Of the various kinds of limestone, the hard oolite is best and magnesian is worst; and it is desirable not to put stations on magnesian limestone if it can be avoided. "4. The Chalk. The chalk, when mixed with clay, and permeable, forms a very healthy soil. The air is pure, and the Water, though charged with calcium carbonate, is clear, 170 TEXT-BOOK OF HYGIENE. sparkling, and pleasant. Goitre is not nearly so common, nor apparently calculus, as in the limestone districts. "If the chalk be marly, it becomes impermeable, and is then often damp and cold. The lower parts of the chalk, which are underlaid by gault clay, and which also receive the drainage of the parts above, are often very malarious; and in America some of the most marshy districts are in the chalk. "5. The /Sandstones. The permeable sandstones are very healthy ; both soil and air are dry ; the drinking-water is, how- ever, sometimes impure. If the sand be mixed with much clay, or if clay underlies a shallow sand-rock, the site is sometimes damp. " The hard millstone-grit formations are very healthy, and their conditions resemble those of granite. " 6. Gravels of any depth are always healthy, except when they are much below the general surface, and water rises through them. Gravel hillocks are the healthiest of all sites, and the water, which often flows out in springs near the base, being held up by the underlying clay, is very pure. " 7. Sands. There are both healthy and unhealthy sands. The healthy are the pure sands, which contain no organic matter, and are of considerable depth. The air is pure, and so is often the drinking-water. Sometimes the drinking-water con- tains enough iron to become hard, and even chalybeate. The unhealthy sands are those which, like the subsoil of the Landes, in southwest France, are composed of silicious particles (and some iron) held together by a vegetable sediment. " In other cases sand is unhealthy from underlying clay or laterite near the surface, or from being so placed that water rises through its permeable soil from higher levels. Water may then be found within 3 or 4 feet of the surface ; and in this case the sand is unhealthy and often malarious. Impurities are retained in it and effluvia traverse it. "In a third class of cases the sands are unhealthy because they contain soluble mineral matter. Many sands (as, for ex- CHARACTER OF THE SOIL. 171 ample, in the Punjab) contain magnesium carbonate and lime- salts, as well as salts of the alkalies. The drinking-water may thus contain large quantities of sodium chloride, sodium carbon- ate, and even lime and magnesian salts and iron. Without examination of the water it is impossible to detect these points. "8. Clay, Dense Marls, and Alluvial Soils Generally. These are always regarded with suspicion. Water neither runs off nor runs through ; the air is moist ; marshes are common ; the composition of the water varies, but it is often impure with lime and soda salts. In alluvial soils there are often alterations of thin strata of sand, and sandy, impermeable clay. Much vegetable matter is often mixed with this, and air and water are both impure. "The deltas of great rivers present these alluvial characters in the highest degree, and should not be chosen for sites. If they must be taken, only the most thorough drainage can make them healthy. It is astonishing, however, what good can be effected by the drainage of even a small area, quite insufficient to affect the general atmosphere of the place ; this shows that it is the local dampness and the effluvia which are the most hurtful. "9. Cultivated Soils. Well-cultivated soils are often healthy ; nor at present has it been proved that the use of manure is hurtful. Irrigated lands, and especially rice-fields, which not only give a great surface for evaporation, but also send up organic matter into the air, are hurtful. In Northern Italy, where there is a very perfect system of irrigation, the rice- grounds are ordered to be kept 14 kilometres (8.7 miles) from the chief cities, 9 kilometres (5.6 miles) from the lesser cities and the forts, and 1 kilometre (1094 yards) from the smaller towns. In the rice countries of India [and America] this point should not be overlooked." Where a wet, impermeable, or impure soil must, of neces- sity, be chosen as a building-site, it should be thoroughly drained. The minimum depth at which drains are laid should 172 TEXT-BOOK OF HYGIENE. be not less than 1^ metres below the floor of the cellar or base- ment. Such a soil should be covered with a thick, impervious layer of asphaltum or similar cement under the house, in order to prevent the aspiration of the polluted ground-air into the building. It is a frequent custom in cities to fill in irregularities of the building-site with street-sweepings and garbage, which always contain large quantities of decomposing organic matters. This is a gross violation of the plainest principles of hygiene. It is almost equally reprehensible to use such decaying or putrefying organic material for the purpose of grading streets or sidewalks in cities and towns. 1 It should be the constant endeavor of all sanitary authorities to prevent pollution of the soil as much as possible in villages, towns, and cities. Where houses are built on the declivity of a hill, the upper wall should not be built directly against the ground, as it would tend to keep the wall damp. A vacant space should be loft between the wall and the ground to permit free access of air and light. In addition to, or in default of, drainage, the drying of soil can be promoted by rapidly-growing plants, which absorb water from the soil and give it out to the air. The sunflower and the eucalyptus tree are the most available for this purpose. III. THE MATERIAL OF WHICH THE HOUSE IS BUILT. The nature of the most appropriate building material de- pends upon so many collateral circumstances that definite rules cannot be laid down. As a general rule, moderately hard burned brick is the most serviceable and available material. It is easily permeable by the air, and so permits natural ventila- tion through the walls, unless this is prevented by other means. 1 During the very fatal epidemic of yellow fever in New Orleans, in 187S, it was ascer- tained that a contractor for street-work used the garbage and street-scrapings to grade the bed of the streets. Kven though in this case it may not have intensified the epidemic in these localities, the practice is so contrary to tin- simplest sanitary laws that it should nowhere be tolerated. The author is aware, however, that the " made-ground " of nearly every city in this country is composed largely of just such material. All sanitarians should protest against a continuance of this pernicious practice. MATERIAL OF WHICH THE HOUSE IS BUILT. 173 It does not absorb and hold water readily ; hence, damp walls are infrequent if brick is used. It is probably, of all building material, the most durable. On account of its porosity a brick wall is a poor conductor of heat. It therefore prevents the rapid cooling of a room in cold weather, and likewise retards the heating of the inside air from without in summer. Another very great advantage is its resistance to a very high degree of heat, brick being probably more nearly fire-proof than any other building material. In hot climates light wooden buildings are advantageous, because they cool oif very rapidly after the sun has disappeared. On account of the numerous joints and fissures in a frame building, natural ventilation goes on very readily and to a con- siderable extent. Next to brick, granite, marble, and sandstone are the most serviceable building materials. Very porous sandstone is, how- ever, not very durable in cold climates, as the stone absorbs large quantities of water, which, in .consequence of the expansion accompanying the act of freezing, produces a gradual but progressive disintegration. The application of paint to the walls, either within or with- out, almost completely checks the transpiration of air through the walls, thus limiting natural ventilation. Calcimining, on the other hand, offers very little obstruction to the passage of air. Wall-paper is about midway between paint and lime- coating in its obstructive effect on atmospheric transpiration. Newly-built houses should not be occupied until the walls have become dry. Moisture in the walls is probably a not infrequent source of ill health; it offers favorable conditions for the development of fungi (possibly of disease-germs), and, by filling up the pores of the material of which the walls are composed, prevents the free transpiration of air through them. Moisture of the walls is sometimes due to the ascent of the water from the soil by capillary attraction. This can be 174 TEXT-BOOK OF HYGIENE. prevented by interposing an impervious layer of slate in the foundation-wall. Where the moisture is due to the rain beating against the outside walls, and thus saturating them if composed of porous materials, a thorough external coating of impervious paint will prove a good remedy. IV. INTERIOR ARRANGEMENTS. A. Size of Rooms, and Ventilating and Heating Arrange- ments. The rooms in dwelling-houses should never be under 2! metres in height from floor to ceiling. In sleeping-rooms the initial air-space should never be less than 35 cubic metres for adults, and 25 cubic metres for children under 10 years of age. Provision must be made for changing this air sufficiently often to maintain it at its standard of purity; i.e., less than 7 parts of carbon dioxide per 10,000. The details for accomplish- ing this will vary with the architects' designs, the material of which the house is constructed, the climate, and the season. The principles laid down in the section on ventilation (Chapter I) should be adhered to. In cold weather the air should be warmed, either before its entrance into the room or afterward, by stove or fire-place. Galton's jacketed stove, or fire-place, seems to answer this purpose admirably. The details of the heating apparatus must be left to individual taste, or other circum- stances. It may be noted, however, in passing, that the pre- vailing method of heating houses by means of hot air is objec- tionable for various reasons ; partly, because the air is usually too dry to be comfortable to the respiratory organs ; partly, because organic matter is frequently present in large proportions, and gives the air an offensive odor when the degree of heat is high enough to scorch the organic matter. Both these objections are, however, removable ; the first, by keeping a vessel of water constantly in the furnace, so that the hot air can take up a sufficient proportion of vapor in passing through, and, the second, by having the furnace made large enough so that the tempera- INTERIOR ARRANGEMENTS. 175 ture need never be raised to a very high degree. Heating by hot water or steam is preferable to the hot-air furnace. Both of these methods are, however, more expensive. Where special ventilating arrangements are necessary, air- a, a, sash: 6, 6, window-jambs ; c, c, window- sill. This cut represents the view from within the Hury Ventilator, in operation. It is broken away at one end to show the sash raised above the outer holes to admit the air. FIG. 7. a, a, sash. This cut represents the view from without the Bury Ventilator, in operation. The sash is hrok'en away to show the ven- tilator behind, with the fresh air passing in. inlets may be inserted at appropriate points in the walls of the room, facing toward the air. A simple arrangement is that known as the Bury Ventilator, shown in Figs. 6 and 7. It consists of a wooden block interposed between the bottom of the lower 176 TEXT-BOOK OF HYGIENE. window-sash and the window-frame. The air passes into the room through the openings in the block, as shown in the illustration. The separation of the upper and lower sashes, when the ventilator t- **T \ i is in place, also adds to the efficiency of the ventilation, as the air passes in through the space so formed. A cheaper ventilator can be made by simply tacking a strip INTERIOR ARRANGEMENTS. 177 of canvas, binders' board, or manilla paper, 20 to 25 centimetres wide, across the lower portion of the window-frame, and then raising the sash 10 to 15 centimetres. The air will pass in under the lower and between the lower and upper sashes and pass upward toward the ceiling and then gradually diffuse itself through the room. In summer a counter-opening may be ob- tained for the escape of foul air by lowering the upper sash, while in winter a stove or fire-place will furnish a good exit. Fig. 8 shows the probable course of the air-currents in a room ventilated by means of a fresh-air inlet near the ceiling and an open fire-place. A is the inlet ; C the fire-place ; G the floor ; F t ceiling ; E E, flues. B. Internal Wall-Coating. A point of considerable im- portance in the outfitting of dwelling-houses is the material used for coating or decorating the inside of the walls. Green paint and green-colored wall-papers should be rejected. The reason for avoiding this color is the following : Bright-green pigments and dyes are largely composed of some compound of arsenic, which becomes detached from the wall or paper when dry. and, being inhaled, produces a train of symptoms which have been recognized as chronic arsenical poisoning. Many cases have been reported in which serious and even fatal poison- ing has been produced in this way. 1 It would be advisable, therefore, to discard all bright-green tints in paints and orna- mental paper-hangings. C. Lighting . Provision should be made in all dwelling- houses for an abundant supply of sunlight. Every room should have at least one window opening directly to the sun. It is not sufficient to give an ample window-space, which should be in the proportion of one to five or six of floor-space, but the im- mediate surroundings of the house must be taken into account. Thus, close proximity of other buildings, or of trees, may pre- vent sufficient light entering a room, although the window- 1 Arsenic in Certain Green Colors, F. W. Draper. Third Annual Report Mass. State Board of Health, 1872, pp. 18-57. 12 178 TEXT-BOOK OF HYGIENE. space may be in excess of that required under ordinary circumstances. Some form of artificial light will also be needed in all dwellings. Certain dangers are necessary accompaniments of all available methods of artificial illumination. The danger from fire is, of course, the most serious. This danger is prob- ably least where candles are used, and greatest where the more volatile oils (kerosene, gasolene) are employed. The use of candles results in pollution of the air by carbon dioxide and other products of combustion to a greater degree than when other illuminating agents are used ; they also give out a larger amount of heat in proportion to their power of illumination. Kerosene gives a good light when burned in a proper lamp, and is cheap, but the dangers from explosion and fire are consider- able. The danger from explosion can be greatly reduced by always keeping the lamp filled nearly to the top, and never fill- ing it near a light or fire. The danger of explosion is increased when the chimney of the lamp is broken, as then the tempera- ture of the metal collar, by which the burner is fastened to the lamp, is rapidly raised 1 and the oil vaporized. If, at the same time, the lamp is only partially filled with oil, the space above it is occupied by an explosive mixture of air and the vapor of the oil. If this is heated to a sufficient degree an explosion will take place. 2 The use of coal-gas is probably attended by less danger than the lighter oils, but by more than other means of illumina- tion. In addition to the dangers from fire and explosions, which are inevitable accompaniments of defects in the fixtures, the escaping gas is itself exceedingly poisonous from the large amount of carbon monoxide it contains. It is, in fact, a very frequent occurrence in large cities that persons are killed by the inhalation of gas which has escaped from the fixtures or was 1 H. B. Baker, in Report Mich. State Hoard of Health, 1876, p. 48. See an instructive paper by Prof. K. C. Kedzie, in Report Mich. State Board of Health for 1877, p. 71 et seq. INTERIOR ARRANGEMENTS. 179 allowed to escape from the burner through ignorance. That variety of illuminating gas known as "water-gas" is more dan- gerous to inhale than coal-gas owing to the larger proportion of carbon monoxide contained in it. The " natural gas " used as a fuel and illuminant in some places in the United States is espe- cially dangerous from the total absence of odor. The gas may escape in large quantity and fail to give notice of its presence except by an explosion, if ignited, or by producing asphyxia in those who incautiously venture into the air permeated by it. The electric light (Edison's incandescent system) is prob- ably open to less objection on the score of danger than any other of the illuminating systems mentioned. There is no trust- worthy evidence that the electric light has any unfavorable in- fluence on the vision, although Regnault supposed it would have a bad effect upon the ocular humors on account of the large proportion of the violet and ultra-violet rays it contained. In order to remove this objection Bouchardat advised the wearing of yellow glasses by those compelled to use this light for close work. The advantages of the incandescent light, besides the brilliant white light it gives, are that it is steady and does not produce any heat, nor does it pollute the air with carbon dioxide and other products of combustion. Professor von Pettenkofer has recently shown experimentally that the pollution of the air by the products of combustion is very much greater when gas is used than where the electric light is employed. The electric arc-lights are extremely dangerous on account of the high poten- tial maintained in the wires, and the difficulty of thoroughly insulating the latter. Many deaths have occurred from this source, and, unless a method is discovered and adopted by which the voltage of the arc-light current can be greatly dimin- ished without decreasing the efficiency of the light, this method ( of lighting must soon be given up in cities, owing to its danger, not only to those directly brought in contact with the conductors, but to others who may indirectly get in the way of the errant current. 180 TEXT-BOOK OF HYGIENE. In writing, sewing, reading, or other work requiring a con- stant use of accurate vision, the light, whether natural or artifi- cial, should fall upon the object from above and on the left side. Hence, windows and burners should be at least at the height of the shoulder and to the left of the person using the light. Increased ventilation facilities must be provided where arti- ficial light (except the electric light) is used to any extent. It has been calculated that for every lighted gas-burner 12 to 15 cubic metres of fresh air per hour must be furnished in addition to the amount ordinarily required in order to maintain the air of the room at the standard of purity. V. WATER-SUPPLY. The water-supply of a dwelling-house should be plentiful for all requirements, and its distribution should be so arranged that the supply for every room is easily accessible. Where prac- ticable, water-taps should be placed on every floor, both for convenience and for greater safety in case of fire. It is also a result of observation that personal habits of cleanliness increase in a direct ratio with the ease of obtaining the cleansing agent. The inmates of a house where water is obtainable with little exertion are much more likely to be cleanly in habits than where the water-supply is deficient or not readily procured. VI. HOUSE-DRAINAGE. Provision must be made for the rapid and thorough removal of waste-water and excrementitious substances from the house. This is most easily and completely accomplished by well-con- structed water-closets and sinks. Water-closets should, however, not be tolerated in any room occupied as a living- or bed- room. It would doubtless be very much more in accordance with sani- tary requirements to have all permanent water-fixtures, water- closets, and bathing arrangements placed in an annex to the dwelling proper. In this way the most serious danger from water-closets and all arrangements having a connection with a HOUSE-DRAINAGE. 181 cess-pool or common sewer permeation of the house by sewer- air could be avoided. Water-closets, however, presuppose an abundant supply of water. Unless this can be obtained and rendered available for flushing the closets, soil-pipe, and house-drain, the dry-earth or pail system should be adopted. Privies should not be coun- tenanced. Experience in several large cities of Europe has demonstrated 1 that the pail system can be adopted with advan- tage and satisfactorily managed even in large communities. As house-drainage may be considered the first and most . important link in a good sewerage system, a brief description will be here given of the details of the drainage arrangements of a dwelling-house. The rapid and complete removal of all fa3cal and urinary discharges, lavatory- and bath- wastes, and kitchen-slops must be provided for. For these purposes are needed, first, water-closets and urinals, wash-basins and bath- tubs, and kitchen- or slop- sinks ; second, a perpendicular pipe, with which the foregoing are connected, termed the soil-pipe; and, third, a horizontal pipe, or house-drain, connecting with the common cess-pool or sewer. A. Water- Closets There are five classes of water-closets in general use. They are the pan-, valve-, plunger-, hopper-, and washout- closets. Pan-closets are those found in most old houses containing water-closet fixtures. Just under the bowl of the closet is a shallow pan containing a little water, in which the dejections are received. On raising the handle of the closet, the pan is tilted and the water at the same time is turned on, which washes out the excrement and sends it into or through the trap between the closet and the soil-pipe. It will be readily understood that the space required for the movement of the pan the " container," as it is termed is rarely thoroughly cleansed by the passage of water through it. Feecal matter, paper, etc., gradually accumu- late in the corners of the container, and, as a consequence, pan- 1 See Chapter v, p. 139. 182 TEXT-BOOK OF HYGIENE. closets are always, after a brief period of use, foul. There are other defects in the construction of the pan-closet which render it untrustworthy, but the one especially pointed out the impos- sibility of keeping it clean is enough to absolutely condemn its use, from a sanitary point of view. It is decidedly the worst form of closet that can be used. Valve-closets are merely modifications of the pan-closet. The bottom of the bowl is closed by a flat valve, which is held in its place by a weight, By moving a lever the valve is tinned down, allowing the excreta to drop into the container. The only differences between the pan- and valve- closets are that in the latter a flat valve is substituted for the pan of the former, and that this allows the container to be made smaller. Otherwise, there are no advantages in the valve-closet. Considered from a sanitary stand-point, the valve-closet is no worse than the pan- clpset, and but very little, if any, better. The third variety, or plunger-closet, has several marked advantages over the two just described. The characteristic feature of the closets of this class is that the outlet, which is generally on one side of the bowl, is closed by a plunger. This bowl is always from one-third to one-half full of water, into which the excreta fall. On raising the plunger, the entire contents of the bowl are rapidly swept out of the apparatus into the soil- pipe, the bowl thoroughly washed out by a sudden discharge of water, and, on closing the outlet with the plunger, the bowl is again partly filled witli water. An overflow attachment prevents accumulation of too large a quantity of water in the bowl. This overflow, however, sometimes becomes very foul and objection- able. The Jennings, Demarest, and Hygeia are types of this class. The principal objection is that the plunger sometimes fails to properly close the outlet, allowing the water to drain out of the bowl, and thus destroying one of its principal advantages. The mechanism is also somewhat complicated and likely to get out of order. The hopper-closet consists of a deep earthenware or enameled HOUSE-DRAINAGE. 183 iron bowl, with a water-seal trap directly underneath. The excreta are received directly into the proximal end of the trap, and when the water is turned on the sides of the bowl are washed clean and everything in the bowl and trap swept directly into the soil-pipe. There is no complicated mechanism to get out of order, the trap is always in sight, and the entire appa- ratus can always be kept clean and inoffensive, as there are no hidden corners or angles for filth to lodge. This form of closet is, all things considered, one of the best for general use. FIG. 9. THE "DECECO" CLOSET. (New Fonn.) The " wash-out " closets are of various shapes, some having the trap in the bowl itself, others having a double water-trap. They are generally simple in construction, and not likely to get out of order. They do not present any decided advantages over the simple hopper, although at the present time they are more used than any other form of closet. Of the recent improvements in this form of closet may be mentioned the "A. G. M.," 1 shown 1 Manufactured by the Myers Sanitary Depot, New York. 184 TEXT-BOOK OF HYGIENE. A FIG. 10. THE "A. G. M." CLOSET. HOUSE-DRAINAGE. 185 in view with cistern in Fig. 10, and in section in Fig. 11, and the " Dececo," Fig. 9, invented by Col. George E. Waring. In the latter the automatic siphon principle, so ingeniously used by Rogers Field in the construction of the automatic flush-tank, is applied to the scouring of a water-closet. Practical experi- ence for six or seven years has demonstrated the great usefulness of this closet. If the delivery of water from the flushing-cistern is properly regulated, at first rapid to thoroughly wash out the FIG. 11. SECTIONAL VIEW OF "A. Q. M." CLOSET. closet and connections, and then slow to re-establish the proper depth of seal in the trap, the closet should be thoroughly satis- factory in its working. Water-closets should not be inclosed in wooden casings, as is almost universally done. Everything connected with the closet, soil- and drain- pipes, water-supply, and all joints and fix- tures should be exposed to view so that the defects can be imme- diately seen and easily corrected. By laying the floor and back of the closet in tiles or cement, such an arrangement can even 186 TEXT-BOOK OF HYGIENE. be made ornamental, as suggested by Waring, 1 who says that a closet " made of white earthenware, and standing as a white vase in a floor of white tiles, the back and side walls being similarly tiled, there being no mechanism of any kind under the seat, is not only most cleanly and attractive in appearance, but entirely open to inspection and ventilation. The seat for this closet is simply a well-finished hard-wood board, resting on cleats a little higher than the top of the vase, and hinged so that it may be conveniently turned up, exposing the closet for thorough cleansing, or for use as a urinal or slop-hopper." Where the arrangement here described is adopted, extra urinals are unnecessary and undesirable. Where they are used they should be constantly and freely flushed with water, other- wise they become very offensive. The floor of the urinal should be either of tiling, slate, or enameled iron. B. Water- Supply for Closets. The water-supply for flush- ing water-closets should not be taken directly from the common house-water supply, but each closet should have an independent cistern large enough to hold a sufficient quantity of water for a thorough flushing (20 to 30 litres) every time the closet is used. The objections to connecting the water-closet directly with the common house-supply are, that there is often too little head of water to properly flush the basin; and, secondly, if the water be drawn from a fixture in the lower part of the house, while the valve of a water-closet in an upper floor is open at the same time, the water will not flow in the latter (unless the supply- pipe is very large), but the foul air from the closet will enter the water-pipe, and may thus produce dangerous fouling of the drinking-water. Hence, separate cisterns for each water-closet should always be insisted upon. The arrangement of these cisterns is often difficult to com- o prehend. Fig. 12 shows the interior arrangement of one form. The ball-shaped float, . extra system of ventilation of traps, so generally insisted upon by plumbers and sanitary engineers, is unnecessary. If the soil-pipe is of the proper size and height, siphonage of traps will not be likely to occur. The waste-pipe connecting the fixture and the soil-pipe should be as short as possible; in other words, all water-closets, urinals, baths, and lavatories should be placed as near the soil-pipe as practicable, in order to have no long reaches of foul waste-pipe under floors or in rooms. Dr. E. S. McClellan has recently invented a trap which obviates many of the objections urged against all previous de- vices, and is intended to meet the defects of the S and other traps. It consists of a body containing a light, inverted cup, with its edges resting in an annular groove containing mercury, which forms an absolute seal against the escape of sewer-air. When HOUSE-DRAINAGE. 189 a slight diminution of pressure occurs on the sewer side of the cup, the greater external pressure lifts the cup out of the mercury and permits a free inflow of air until the wonted equilibrium is re-established, when the cup drops back into the mercury by gravity, and effectually closes the trap against any outflow. With this trap siphonage of the seal is impossible. Fig. 14 shows this trap with the cup down, and Fig. 15 with the cup raised, allowing inflow of air. For an ordinary wash-bowl or bath-waste (which should FIG. 14. SECTIONAL VIEW OF VENT, WITH UUP IN NORMAL POSITION. FIG. 15. SECTIONAL VIEW OF VENT. WITH CUP LIFTED OUT OF THE MERCUBY BY THE INFLOWING CURRENT OF AIR INDICATED BY THE ARROWS. always be trapped), the Connolly globe- trap, shown in Figs. 16 and 1 7, is an excellent fixture. It is impossible, under ordinary circumstances, to break the seal by siphonage. D. The Soil- Pipe. The vertical pipe connecting the water-closets and other fixtures with the house-drain is called the soil-pipe. It should be of iron, securely jointed, of an equal diameter (usually 10 centimetres) throughout, and extend from the house-drain to from 1| to 2 metres above the highest point of the house. The connections of all the waste-pipes from water-closets, baths, etc., should be at an acute angle, in order 190 TEXT-BOOK OF HYGIENE. that an inflow at or nearly at right angles may not produce an obstruction in the free passage of air up and down the soil-pipe. The diameter of the soil-pipe, at its free upper end, should not be narrowed; in fact, according to Col. Geo. E. Waring, the up-draught is rendered more decided if the upper extremity of the soil-pipe is widened. 1 The internal surface of the pipe should be smooth, and especial care should be taken to prevent projections inward at the joints; otherwise, paper and other FIG. 16. CONNOLLY GLOBE-TRAP. FIG. 17: GLOBE-TRAP ATTACHED TO BASIN. matters will adhere to the projections, and gradually obstruct the pipe. E. The House-Drain. The horizontal or slightly inclined pipe which connects the lower end of the soil-pipe with the sewer or cess-pool, the point of final discharge from the house, should be of the same diameter and material as the soil-pipe. The joints should be made with equal care, and the pipe should be exposed to view throughout while within the house-walls. Am. Architect, p. 124, Sept 15, 1883. HOUSE-DRAINAGE. 191 If sunk below the floor of the cellar it should be laid in a covered trench, so that it may be readily inspected. The junc- tion between the vertical and horizontal pipe should' not be at a right angle, but the angle should be rounded. The drain-pipe should not be trapped. This is contrary to the advice of sanitary authorities generally, but the author thinks it unadvisable to trap the drain-pipe. There should be no obstruction to the outflow of sewage from the house, and a trap in the drain-pipe is of no avail against the passage of sewer-air from the sewer or cess- pool into the soil-pipe, if the pressure of the air in the former is increased. Furthermore, if the passage of air backward and forward between the sewer and the external air at a sufficient height (above the roofs of houses, for example) is free and unobstructed, the sewers (or the cess-pool, as the case may be) will be better ventilated than if an obstruction to such free circulation, in the form of a trap, be placed in the drain-pipe. . Nearly all sanitary authorities direct that an opening for the admission of fresh air "fresh-air inlet" should be made in the drain-pipe, before its connection with the sewer or cess- pool. This is done with the view of having a constant current of fresh air entering near the base of the soil-pipe and passing upward through it. Theoretically the current ought always to pass in this direction. Practically, however, the current is found, at times, to pass the other way, and the foul air from the soil-pipe may be discharged into the air near the ground, where it would be much more likely to do harm than when discharged high up in the air beyond the possibility of being breathed. OFFICIAL SUPERVISION OF THE SANITARY ARRANGEMENTS OF DWELLINGS. In most cities and towns the municipal authorities have provided for an official inspection of buildings, to prevent neglect of precautions against fire and other manifest dangers to life. It is only very recently, however, that the authorities of some of the larger cities in this country have enacted laws to prevent 192 TEXT-BOOK OF HYGIENE. improper construction of house-drainage works. Although none of these laws or ordinances cover the subject completely, yet their proper enforcement must result in great advantage. Within the past few years, following the example of Edin- burgh, volunteer associations have been organized in various cities of this country', with the object of securing constant expert inspection and supervision of the drainage arrangements of dwellings and other necessary sanitary improvements. The good results accomplished by the Newport Sanitary Protection Society, the New Orleans Auxiliary Sanitary Associa- tion, and other similar bodies attest the usefulness of such organizations. [The following works are recommended to the student who desires a fuller knowledge on the subjects treated in this chapter : W. H. Corfield, Dwelling-Houses, Their Sanitary Construction and Arrangements, N. Y., 1880. Win. Paul Gerhard, House-Drainage and Sanitary Plumbing, Fourth Report State Board of Health of R. I., 1881. Eliot C. Clarke, Common Defects in House-Drains, Tenth Annual Report Mass. State Board of Health, 1879.] QUESTIONS TO CHAPTER VI. CONSTRUCTION OP HABITATIONS. Why should the principles of hygiene he observed in the construc- tion of dwellings ? What relation is there between badly-constructed and overcrowded dwellings in cities? Between overcrowded dwellings and the death-rate, either general or from contagious diseases ? What class of persons are especially atfected by overcrowding and unsanitary conditions of their dwellings ? What points should be taken into consideration in building a house? What things are to be sought and what avoided in selecting a site ? On what kind of soil should the house be built ? How far should the ground- water be below the surface, even at its highest? What must be known about a soil to determine whether it is sanitarily suitable for building purposes? What is the usual judgment concerning sites on granite, ti-ap, or metamorphic rocks ? What if they have been disintegrated ? What regarding those on the clay slate ? Limestone and magnesian limestone? Chalk? Sandstone? Gravel? Sands? Clays and alluvial soils? Cultivated lands? Which of the above is probably the best, on general principles, for the site for a dwelling ? Where a site is wet or the soil is impure, what must be done ? What is the minimum depth at which drains for the soil-water should be laid ? How else may the drying of the soil be promoted? How should a cellar or basement over an impure soil be paved? What precaution should be observed in building a house against a hill ? What are some of the materials of which the walls of a house may be built ? What are the advantages of good brick ? Why should very porous sandstone not be used for building purposes in cold climates? What is the effect of paint upon house-walls ? Has calcimining or white- washing the same effect? Has wall-paper? How soon should newly -built houses be occupied ? To what are moist walls sometimes due, and how may they be obviated ? What should be the minimum height of rooms in dwelling-houses? How much air-space should there always be in sleeping-rooms for adults and children ? What is the standard of purity of the air that should be maintained constantly ? What are the objections to heating by hot-air furnaces, and how may these objections be avoided ? How may a room be ventilated without expensive apparatus ? What colors should be avoided in wall-paper and paints for inside work, and whj- ? What should be the proportion of window-space to floor-space, and what other points' should be observed in the day-lighting of rooms ? What are the forms of artificial light used for household 13 (193) 194 QUESTIONS TO CHAPTER VI. illumination, and what are the dangers accompanying each ? What are some of the especial advantages of the incandescent electric light? From what direction should the light come for writing, reading, etc. ? Why must there be increased ventilation where artificial lights (except incandescent electric) are used ? How much fresh air per hour is needed to properly dilute the impurities produced by burning illuminating gas ? What points are to be observed regarding the water-supply of a dwelling ? Why should it be both abundant and convenient ? How are waste-waters and excrementitious matters most readily removed from a house ? Where would it be best to have all fixtures, etc., of a house-drainage system located, if possible? What do water- closets, etc., presuppose? If this cannot be had, what system should be adopted instead ? For what must a proper house-drainage system pro- vide ? What are the component parts of such a system ? Where should water-closets never be located ? What five classes of water-closets are there? Which of these are most objectionable, and why? Describe briefly the construction of a pan- and a valve- closet. In what way is a plunger-closet better than a pan- or valve- closet ? Wherein is it sanitarily imperfect? Why is the hopper-closet one of the best? What two kinds of hopper-closet are there? What can be said of the wash-out closets? What is the principle of siphon closets? Why should water-closets and other fixtures not be inclosed in wooden casings ? How may the surroundings of such closets and fixtures be further im- proved ? Why should the water-supply for closets not be taken directly from the house-supply? How much should the flushing cistern hold? What are traps ? Where should they be located ? How many should there be in any system of house-drainage ? What is the simplest form of trap ? What are its advantages ? Upon what does the value of a trap depend ? What is to be avoided in the selection of a trap ? What is meant by siphouage ? How can this be prevented ? To what part of the trap is the vent-pipe to be attached ? Where should the other end of the vent-pipe open ? How else may the seal of a trap be broken ? What is the principle of McClellan's anti-siphon trap? How long should the waste-pipe connecting the fixtures with the soil-pipes be ? What is the soil-pipe ? Of what dimensions should it be? Where should its upper extremity end? What other precautions should be observed in regard to the soil-pipe? What is the house-drain ? What care must be observed in the laying of it ? What can you say regarding a trap between the house-drain and sewer? If a trap is thus located, what else must there be between the trap and the house. :uid why? What can be said regarding the official supervision of sanitary arrangements in dwellings ? CHAPTER VII. CONSTRUCTION OF HOSPITALS. SITE. IF the choice of a site for the habitations of healthy per- sons is a matter of vital importance, as was pointed out in the last chapter, it needs no argument to impress upon the reader the actual necessity of choosing a site with wholesome surround- ings for a habitation for the sick. In selecting a site for a hos- pital, therefore, it is of prime importance to avoid a location where unsanitary influences prevail. While a hospital should always be easily accessible, it is not desirable that it should be in a noisy or crowded part of a city. Where a hospital is primarily designed for the reception of accident or " emergency " cases, it is, of course, necessary to have it near to where accidents are likely to occur. In a city this will probably be in the most crowded and noisy part. The direction of the prevailing winds from the city should be avoided in selecting a site for a hospital. Free admission of sunlight and air must be secured to all parts of the 'hospital. An elevated location is therefore desir- able, although exposure to violent winds must, if possible, be avoided. The soil upon which a hospital is built should be clean, easily drained, with a deep ground-water level, not liable to sudden oscillations. The neighborhood of a marshy or known malarious region should be avoided. THE BUILDINGS, The building area must be large enough to permit the construction of buildings in accordance with the modern recog- nized principles of hospital construction. Overcrowding is not (195) 196 TEXT-BOOK OF HYGIENE. permissible, either of the grounds by buildings or of the build- ings by patients. Having determined the number of patients for whom pro- vision is to be made and the character of the diseases to be treated, an estimate must be made of the area necessary for a hospital. Taking into account all the buildings needed, the area required will be for two or more storied buildings not less than 30 square metres per bed. If one-story buildings are to be erected more space will be required, and if infectious diseases are to be treated in the hospital the above space-allowance must be doubled or trebled. In the new Johns Hopkins Hos- pital, in Baltimore, the area occupied by the buildings is 56,000 square metres, and provision is to be made for 300 patients. This, covering, of course, the area occupied by the administra- tion building, nurses' home, kitchen, dispensary, operating and autopsy theatre, laundry, etc., gives an area of 187 square metres per bed. The actual allowance of floor space per bed is 11^ square metres ; for patients with infectious diseases the space- allowance is nearly treble, being 29 square metres. Within recent years the principles of hospital construction have undergone considerable modification. While formerly a large hospital consisted usually of one large, two or more storied building, in which all the various departments were comprised under one roof, the aim has recently been to scatter the wards as much as practicable consistent with reasonable ease of supervision and administration. Under the former plan, with large wards connected by common corridors and stairways, ease of administration was primarily secured; in the latter, the most important object of a hospital, " a place for the sick to get well in," is more nearly attained. While many hospitals are still being constructed on the old plan, of a single block of several stories in height, nearly all sanitary authorities are agreed that the plan of separate pavilions of one or, at most, two stories, in which the buildings are entirely disconnected, or connected only by means of an open corridor for convenience of THE HOSPITAL BUILDINGS. 197 administration, is best for the patients, and, leaving out of account the cost of the ground, is also the most economical. The recent development of the pavilion system of hospitals may be attributed largely to the success obtained in treating the sick and wounded in the simple barrack hospitals during the late war between the States. The army barrack hospital is the original type of the pavilion hospital of the present day. Each pavilion consists of one or two wards, containing from ten to thirty beds altogether. In each pavilion or ward is also a bath- and wash- room, water-closet, dining-room, scullery, attendants' room, and sometimes a day-room for patients able to be out of bed. The two-story pavilion is built on the same plan, and is generally adopted in cities, or where economy of space is desir- able for financial reasons, and where no infectious diseases are treated. Where practicable, one-story pavilions should always be adopted, as they are more easily heated, ventilated, and served than two-storied buildings. When a number of pavilions or wards are connected by a corridor with each other, and with a central or administration building and other service buildings, the aggregation constitutes a modem pavilion block-hospital. The Johns Hopkins Hos- pital, already referred to, is a model hospital of this class, and its plans should be studied in detail by all who are more par- ticularly interested in hospital construction. The general wards are in one- and two- story buildings, connected by a corridor with each other and with the administration and service buildings. In addition to two buildings containing private rooms and small wards for patients able to pay for the extra accommodations, there is a line of pavilions running from east to west. The corridor cuts all the pavilions near the north ends of the build- ings, separating the ward almost entirely from the service part of the building. This arrangement leaves the south, east, and west fronts of the wards entirely exposed to the sun's rays, a very important advantage. The kitchen and laundry are at 198 TEXT-BOOK OF HYGIENE. opposite angles of the grounds, while the autopsy building is placed in the extreme northeast corner of the grounds, as far from all the wards as practicable. The free space between the separate pavilions should be at FIG. 18. PLAN OF JOHNS HOPKINS HOSPITAL. A. Administration Building. B. Female Pav-Ward. C. Male Pav-Ward. D. Male Surgical Ward. E. Female Surgical Ward. F. Male Medical Ward. G. Female Medical Ward. H. Gynecological Ward. I. Isolating Ward. K. Kitchen. I,. Laundry. N. Nurses' Homo. O. Dispensary. R. Patho- logical Building. S. Stable. U. Amphitheatre. X. Apothecary's Building. Y. Bath-IIouse. least twice the height of the building. In the Johns Hopkins Hospital, the space is 18 metres between the one-story common wards, which are 11 metres in height from the surface of the ground to the ridge of the roof. VENTILATION AND HEATING. 199 VENTILATION AND HEATING. The cubic space (initial air-space) per bed in the wards should not be less than 1500 to 2000 cubic feet (42 to 56 cubic metres), and for surgical or lying-in cases and contagious dis- eases, 70 cubic metres should be allowed. The ventilating arrangements should secure an entire change of the air two to three times in an hour. In most sections of the United States, natural ventilation can be relied on to keep the air in hospital wards pure (assum- ing, of course, the proper construction of the buildings). The windows, doors, and walls are important factors in securing this ventilation. Hence, especial care is to be paid to their con- struction and arrangement. Many German, French, and English authorities on hospital building urge the importance of making the walls impervious by cement, glass, or paint. The peculiar odor known as " hos- pital odor," it is asserted, cannot be prevented in any hospital in which the floors, walls, and ceilings are' not absolutely imper- vious. The American practice is generally in favor of walls which permit transpiration of air. In the experience of the author the imperviousness of the walls is not necessary to secure freedom from hospital odor. It remains a question for serious consideration whether the diminution of natural ventilation would not counterbalance any good resulting from non-absorp- tive walls. The interior of the walls should be perfectly smooth and plain; no projections, cornices, or offsets of any kind are per- missible. The desirability of this restriction was clearly ex pressed over a hundred years ago by John Howard : " From a regard to the health of the patients, I wish to see plain, white walls in hospitals, and no article of ornamental furniture intro- duced." 1 Windows should run quite to the ceiling, and should not be arched, but finished square at the top. There should be one 1 An Account of the Principal Lazarettos of Europe, etc., p. 57. London, 1791. 200 TEXT-BOOK OF HYGIENE. window for every two beds. The window-sash should be double to retain heat, and the lights heavy, clear glass. Ventilation can be promoted by raising the outer sash from below and lowering the inner one from above. The insertion of a Sher- ringham ventilator at the top of the inner sash will aid in giving the incoming air-current an upward direction. Heating is best accomplished by introducing hot air from without, or by stoves or fire-places in the centre of the wards. Where hot air is introduced from without, it should be heated by passing it over steam- or hot- water coils, and not by passing it through a furnace, which may produce super-heating and excessive dryness of the air. In a series of experiments by Dr. Edward Cowles at the Boston City Hospital, 1 the air was heated to 32 by passing it over steam-coils. It was admitted to the wards by numerous inlets 30 centimetres square. The best velocity for ventilating and warming purposes was found to be 54 metres per minute. Exit openings were in the ceiling, and it was found best to make them large, as by this means the rapidity of exit currents is reduced. Where the warming of the ward must be accomplished by stoves or fire-places in the ward, the best plan, for square and octagon wards, is to have a large central chimney with arrange- ments on the four sides for fire-places or stoves. This chimney can also be used as a very efficient ventilating shaft throughout the year by a device put in practice by Mr. John R. Neirnsee, architect of the Johns Hopkins Hospital. 2 In oblong wards, two or more large stoves, placed at equal distances along the centre of the wards, will heat the wards effectually. Floors should be made of tiles, slate, or oak or yellow-pine lumber. If wood is used, it should be well seasoned, perfectly smooth, and all joints accurately made. The floor should be kept constantly waxed to render it impervious. to fluids. 1 Report of the Massachusetts State Board of Health for 1879. pp. 231-248. * Hospital Construction and Organization : Plans for Johns Hopkins Hospital, p. 335 et seq. New York, 1875. ' VENTILATION AND HEATING. 201 The space between the floor and ceiling below should be filled with some fire-proof non-conducting material, such as cement or hollow bricks, in order to isolate each floor or ward as much as possible from others, both to prevent transmission of noise and extension of fire. All corners and angles on the inside of the building should be rounded to facilitate the removal of dust. In cleaning up, care should be taken not to stir up the layers of dust too much by active sweeping or dusting. The floors, furniture, door- and window- casings should be wiped off with damp cloths. Soiled bedding, clothing, dressings, and bandages must be promptly removed from the ward. Mat- tresses and other bed-clothing should not be shaken in the ward. 1 Water-closets or (where the dry method of removal of ex- creta is in use) earth- or pail- closets should be placed where they can be easily reached by the patients, but the apartment in which they are placed must not open directly into the ward. The entrance to this apartment should be from the corridor or, better still, from the open air. The ventilation of water- closets should be . independent of and entirely distinct from that of the ward or other part of the hospital building. It is, of course, unnecessary to more than call attention to the vital importance of the prompt removal of all excreta, both solid and liquid, from the ward or hospital building. To at- tempt disinfection of excreta and allow them to remain in the ward after being voided is a pernicious practice, which should under no circumstances be permitted. All utensils for the re- ception of excreta, bed-pans, etc., should be immediately emptied and thoroughly cleansed. Urinals are not advisable ; the simple hopper-closet with hinged, hard-wood seat, as described in Chapter VI, is sufficient. A bath-room and lavatory should be attached to every ward. It should be placed in the service building, and be 'A Wornioh : Ueber Verdorbene Luft in Krankenraeumen. Volkmann's Samml. Klin. Vortr., No. 179, p. 24. 202 TEXT-BOOK OF HYGIENE. easily accessible to the patients. There should also be portable bath-tubs in order that baths may be given in the wards when necessary. Every large general hospital should also have a special apartment or building where baths of various kinds, such as medicated, vapor, Turkish, and Russian baths, could be given. In lying-in hospitals, special arrangements for giving vaginal and uterine douches must also be furnished. A daily water-supply of at least 450 litres per bed should be provided. The water should be easily accessible from the wards and various parts of the service building. All water-closets, soil- and waste- pipes must be properly trapped ; all joints must be properly made and all sewer con- nections made on the most improved plans. All work of this sort should be properly tested before being accepted, and frequently inspected afterward. No sewer or house-drain should be laid under a ward. A disinfecting chest for disinfecting soiled clothing, bed- ding, dressings, etc., should be placed in the basement of the ward, and connected with the latter by an iron chute, closing perfectly by an iron top. The best and most convenient disin- fectant is steam. This is also the best means to destroy vermin in clothing and bedding. It is questionable whether a nurse's room should be attached to a hospital ward. The nurse's place, when on duty, is in the ward itself, not in a room separate from it. Where there is a nurse's room, it should not be furnished with sleeping arrangements, for this is a strong temptation to neglect of duty on the part of the nurse. A nurse not on duty should not be permitted to remain about the ward. A ward-kitchen should be in the service building, where articles of food can be kept hot or cold when necessary, and where special dressings, cataplasms, hot water, etc., can be pre- pared. A small gas-stove only should be allowed in the ward- kitchen, as the regular meals of the patients are prepared in the ADMINISTRATION AND MANAGEMENT OF A GENERAL HOSPITAL. 203 central kitchen, which should be totally detached from the hospital. The ward-kitchen can be easily utilized as a nurse's room, and in a small hospital can also be used as a store-room for the patients' body- and bed- linen and clothing. The dining-room for patients able to be out of bed should be in the service building. A room with a good light and well ventilated and heated should be selected for this purpose. In the intervals between meals this room could be used as a day- room for such patients as should be out of bed, but who are not able to be in the open air. A dead-house, containing a dead-room, autopsy-room, and a room fitted up for rough microscopic and possibly photo- graphic work, is a necessity to every well-appointed general hospital. The dead-house should be entirely separate from the ward buildings. The kitchen should be separate from the other buildings, and in large hospitals should also be the central station for the heating arrangements, if hot water or steam are to be used. The laundry may be connected with it. The kitchen should be con- nected with the wards by means of a covered corridor to avoid exposure in carrying the food to the wards. The administration building should contain office-rooms for the superintendent and resident physician, pharmacy, library, reception-rooms for visitors, living-rooms for one or more assist- ants, and dwellings for the superintendent and resident physician. THE ADMINISTRATION AND MANAGEMENT OF A GENERAL HOSPITAL. The general management of a hospital should be under the direction of a superintendent, who, besides being a medical man, should be especially qualified by study and experience for the work. The superintendent of a large hospital should not be expected to perform any of the routine professional work in the wards, but he should be responsible for the service, both profes- sional and lay, in the hospital. He should be the financial officer, and in all other things concerning the hospital his 204 TEXT-BOOK OF HYGIENE. judgment should decide. He should have sufficient assistance to permit all necessary duties to be promptly performed. For this purpose he should have a secretary, or clerk, who should not be a medical man; otherwise the attention of the latter might be withdrawn from his clerical duties to the more inter- esting professional work in the hospital. The plan advocated by some authorities, to have two superintendents for large hos- pitals, one of whom shall be a medical man and direct only the professional work of the hospital, while the other shall have charge of the administrative functions, does not commend itself to the author. It involves a division of responsibility which will, in nearly all cases, eventually lead to differences of opinion likely to prove unfavorable to the best interests of the hospital. It is customary in this country to appoint as resident physi- cians and surgeons in hospitals, recent graduates, whose functions are usually limited to carrying out the directions of the visiting physicians and surgeons, and sometimes to act on their own responsibility in emergencies. This system has some advantages for the physicians, but is usually detrimental to the best interests of the patients. The resident medical officer in a large hospital should always be a thoroughly qualified, experienced physician, capable of deciding promptly when the occasion arises, and he should be responsible to the superintendent for the proper per- formance of his professional duties. Necessarily, a physician with the qualifications indicated, would demand a very much larger salary than is usually paid resident physicians, but it should be understood that no hospital in which the good of the patient is the first consideration can be conducted on a cheap basis. Visiting physicians and surgeons and all resident medical officers should be chosen with reference to their general and o special qualifications for the duties expected of them. It would seem to be a good plan to make the selections for subordinate positions, at least, by competitive examination. The sick in a hospital should be properly classified. Male ADMINISTRATION AND MANAGEMENT OF A GENERAL HOSPITAL. 205 and female patients should, of course, be treated in separate wards. A primary classification into medical, surgical, and obstetrical cases or wards is also indicated. Infectious dis- eases, such as typhoid fever, erysipelas, cholera, yellow fever, croupous pneumonia, etc., should not be treated in the same wards with rheumatism, Bright's disease, cardiac and nervous disorders, or simple digestive derangements. It is questionable, however, whether it is advisable to make a very elaborate classi- fication of the various diseases except in very large hospitals. An accurate record, made at the time of observation, and not written from memory afterward, should be kept of the his- tory and progress of every case. The record should show not merely the symptoms and diagnosis, but the medical and hy- gienic treatment. In most hospitals where such records are kept the entries are made either in a simple memorandum-book or in a more or less complicated case-record. A simple form of case-record has been devised by Surgeon-General Walter Wyman, of United States Marine-Hospital Service, which seems to possess advantages that render its general adoption desirable. In hospitals where cases of surgical diseases and injuries are received, a special apartment should be fitted up as an operating- room. Operations should not be performed in award in the presence of other patients. [The following works are recommended for additional study upon this subject: Hospital Construction and Organization ; New York, 1875 (espe- cinll}' the essays of Drs. Billings, Folsom, and Stephen Smith). Kran- kenanstalten, by L. Degen, in Y. Pettenkofer und Ziemssen's Hand- buch der Hygiene. Spital,by C. Bohm,in Realencyclopadie d. ges. Heil- kunde, Bd. XII. General Principles of Hospital Construction, by F. H. Brown, in Buck's Hygiene and Public Health, vol, i. Schumburg, Hygienische Grundsatze beirn Hospitalbau.] QUESTIONS TO CHAPTER VII. CONSTRUCTION OF HOSPITALS. What would govern you in selecting a site for a hospital ? What will go to determine the building area ? In calculating the area required for buildings, what relation has it to the number of beds in the hospital ? In the wards, what should be the actual minimum floor-space for each bed for non-infectious and for infectious diseases ? What is the differ- ence in the principles of modern hospital construction and of those for- merly in vogue ? What are some of the advantages of the modern plan ? What was the prototype of the present system? How many wards should each pavilion contain at the most ? How many beds in each ward? What conveniences should there be in each ward or pavilion? What is meant by a pavilion block-hospital ? What space should there be between the separate pavilions? What cubic space per bed should there be in the ordinary wards ? What cases need more, and how much ? How often should the air be entirely changed in the wards ? Should the walls be pervious or imper- vious to the passage of air ? How should the walls be finished ? How many windows should there be in each ward ? How high should they be ? What is the best way to heat a hospital ward ? How should hot air be warmed ? If a ward is to be warmed by fire-places or stoves, how should they be arranged ? Of what materials should the floors be made ? How should they be treated ? What should there be between ceilings and the floors above ? Why? How should the corners and angles of floors and ceilings be finished ? How should the wards be cleaned ? What should be done with soiled bedding, etc. ? Where should the water-closets, etc., be located ? How should they be ventilated ? How much water should be furnished per bed? Why should no sewer or house-drain be laid under a ward ? Where should the nurses' rooms be? Where the ward kitchen and dining-room? What is the administration building for, and what should it contain ? What officers are necessary for the management of a hospital ? What are their duties ? How should the resident physicians be qualified and selected? How should the sick be classified, and what wards should there be in a general hospital ? Mention some of the details that should be noted in the case records. (206) CHAPTER VHI. SCHOOLS. THE hygiene of schools comprises the consideration of the sanitary principles underlying the construction of school-houses and school-furniture; the proper amount of time to be devoted to study at different ages ; the special diseases of school-children, their causes, and means for their prevention. CONSTRUCTION OF SCHOOL-HOUSES. In the construction of school-houses the same hygienic principles are applicable as in dwelling-house construction. The selection of a site for the school-building should command the same careful consideration that is necessary in determining upon a site for a dwelling. Proximity to marshes and other unsan- itary surroundings should be avoided. If the soil is damp it should be properly drained, and all sources of insalubrity in the neighborhood avoided or, if possible, removed. School-houses should not be over three stories high ; cor- ridors and stairways should be wide, straight, and well lighted. All stairs should be securely built, and be guarded with ample, strong railing. All doors should open outward to permit ready egress and reduce the danger of accident in panics from any cause. In addition to the study- or recitation- rooms, provision should be made for play and calisthenic-exercise rooms. Well- lighted and ventilated side-rooms should be provided for the reception of outside clothing, umbrellas, overshoes, etc. These articles should not be kept in the recitation- or study- rooms. Floors should be made of accurately-joined flooring, and rendered impervious by oil or paraffine coating. (207) 208 TEXT-BOOK OF HYGIENE. Appropriate measures must be employed to prevent the permeation of the building by ground-air. The inside walls of school-rooms may be tinted a neutral gray, or light blue or green. Ceilings should be white. Walls and ceilings should not be painted, but lime-coated to permit free transpiration of air. Schools should be so constructed as to permit of ready heating and ventilation, cleaning, and keeping clean. In large schools the method of heating will usually be by furnace-heated air, although a better method would probably be by steam- or hot- water pipes. The ventilation of school-rooms must be carried out on the principles indicated in Chapter I. With careful and intelligent teachers, natural ventilation will give better satisfaction than a complicated artificial system. Where windows and doors must be largely depended upon for ventilation, the Bury window ven- tilator, illustrated on a previous page, will give satisfactoiy results unless the school-room is overcrowded. Opening the doors and windows when the pupils are out of doors flushing the rooms with fresh air is an excellent aid, and is even useful in cases where the most elaborate artificial system of ventilation is in use. A model study-room, according to modern views, should be about 9 to 10 metres long, not over 7 metres wide, and 4 to 4^ metres high. Such a room could be easily lighted by win- dows on one side only, and readily heated and ventilated. It would also enable the teacher to exercise a close supervision over his pupils. In a room of this size forty pupils would be a proper number, although fifty could be accommodated. The initial air-space for each pupil would be 5.60 cubic metres if there were fifty pupils in the room, and 7 cubic metres if there were only forty. This would be slightly reduced by the allowance for the teacher. It is believed that study-rooms should face toward the north. The light entering from the north side of a building would be equable during a whole day. While a larger window CONSTRUCTION OF SCHOOL-HOUSES. 209 surface would be necessary than with an easterly or southerly exposure, it is held that the light, being devoid of all glare, would be more effective. Where the light is admitted on the east, south, or west sides of the building, the direct entrance of the sun's rays must be prevented by curtains, by means of which the amount and proper distribution of the light is regulated with difficulty. The windows of the school-room should reach from about the height of the pupil's shoulder (when seated) to nearly or quite to the ceiling. Arches or overhanging cornices over the windows should be avoided, as they cut off much light. For the same reason the near proximity of other high buildings and of trees should be avoided in selecting a site for a school- house. The window area should be not less than one-fifth of the floor area, otherwise the light will be deficient. The light should be admitted only from the left side of the pupil. When admitted from the right side the shadow cast oy the pen in writing interferes with good vision ; if admitted directly in front of the pupil, the glare of the light will injuri- ously affect the eyes ; while, if it enter from behind, the book or paper of the pupil will be so much in shadow as to compel him to lean so far to the front in bringing his eyes nearer to book or paper that nearsightedness is very likely to be devel- oped. Furthermore, if the light is admitted into the room at the backs of the pupils, the eyes of the teacher are liable to suffer from the constant glare. In a school-room of the dimensions above stated, a row of windows on one side, forming an area of glass one-fifth of the floor-space, will thoroughly and satisfactorily illuminate the room, with the least unfavorable influence upon the organs of vision. It is advisable, therefore, to always insist on this arrangement of lighting of school-rooms. Where artificial light is used in a school-room, it should be in the proportion of one burner to every four pupils. All burners should be provided with chimneys and vertical reflectors. u 210 TEXT-BOOK OF HYGIENE. Water-closets and privies should not be placed in cellars or basements. This would seem to be self-evident, and yet in many city school-houses these places of retirement are in this unsuitable location. When it is considered that large schools are frequently warmed by hot air taken from the cellar, it furnishes an additional reason to avoid this location for water- closets. On the contrary, the custom, in some country schools, of placing the privy at a considerable distance from the school- room and in an exposed situation, is almost equally reprehen- sible, as the pupils, especially girls, are prone to neglect obeying the calls of nature, from which neglect many disorders arise. In a recently-introduced system of ventilation and excre- ment removal for schools, the closets are in the basement, and the excrement, as Yoided, is rapidly dried by a current of air, and the odor in this way quickly destroyed. Unfortunately, in thus drying the excrementitious matter, micro-organisms may be taken up in the air-currents and carried into the school-rooms. SCHOOL FURNITURE. Desks should be slightly sloping, the edge nearest the pupil being about 1 inch (2.5 centimetres) higher than his elbows. The front edge of the seat should project a little beyond the near edge of the desk, so that a plumb-line dropped from the latter should strike the seat near its front edge. If the seat is not thus brought slightly under the desk, the pupil is compelled to lean forward in writing, which position prevents proper ex- pansion of the chest and increases the blood-pressure in the eyes, a condition promotive of near-sightedness. Seats should be only high enough so that the feet rest flat upon the floor. If they are higher, a foot-board must be pro- vided. Children should not be condemned to the cruelty of having their feet dangling " between heaven and earth " while they keep their seats. Seats and desks should be graded according to the sizes of the pupils not their ages or standing hi the class. SCHOOL FURNITURE. 211 An ideal seat and desk would be one made to measure for each pupil, but this is manifestly impracticable, inasmuch as with the constant growth of the child the seats would be rapidly outgrown. The desk shown in Fig. 19 l is adjustable to children of different sizes, and seems to solve the problem which has so long puzzled the school sanitarian. The desks are made for a single pupil and the seat and desk are independently adjustable. FIG. 19. ADJUSTABLE SCHOOL-DESK. (Front View.) t The frame is of iron and the seat, back, and desk of hard-wood lumber. Blackboards should not be placed at a greater distance than 10 metres from the farthest pupil. The ground of the board should be a dead black, without lustre. In writing exercises upon the board, care should be taken that the letters and figures are made sufficiently large, and with rather heavy strokes of the crayon, in order that they may be easily seen from the most distant part of the room. It has recently been demonstrated that a black letter on a white ground can be seen at a greater distance than 1 Made by the Rushville School Furniture Company, Rushville, Ind., U. S. A. 212 TEXT-BOOK OF HYGIENE. a white letter on a black ground. Hence, it might prove advantageous to the eye-sight of school-children to substitute for the present blackboard and chalk, a white board and black crayon. In some European lecture-rooms this plan has been adopted with satisfaction. AMOUNT OF TIME TO BE DEVOTED TO STUDY. Young children should not be kept at the same study or in the same position for long at a time. The exercises should be frequently varied. It is especially with children in the primary grades that care should be taken not to overburden their minds with too many hours of study, or too long con- tinuance at the same exercise. Children should not be placed in school much, if at all, before the completion of their 7th year. From 7 to 9 years they should be kept at their studies not longer than three hours daily; from 9 to 12 years four hours may be allotted them; and from 12 to 16 years they may be kept at mental work five to six hours daily. This does not mean that pupils are to be kept continuously at their studies during these hours, but that they should be neither compelled nor permitted to study longer than these periods each day. It is believed that these figures repre- sent the capacity for endurance in the majority of children, and they .should be adopted in all schools where the largest return in mental acquirements is desired at the least expenditure of health. Excess of time expended in study is almost certainly followed by physical deterioration. " A little less brain : a little more muscle," for our children, is a legitimate demand that we may make of legislators and school-boards. Gymnastic exercises should form part of the daily routine in all schools. These exercises should take place, when practi- cable, in the open air. Playing, romping, laughing, and sing- ing should be encouraged, rather than the natural tendency to boisterous play restrained. It is especially desirable that female children should be encouraged to take part in these DISEASES OF SCHOOL-CHILDREN. 213 diversions. The desire, on the part of many parents, to see little girls deport themselves as young ladies, before the time even when they write their age in two figures, is very rep- rehensible, and deserves the most unqualified condemnation. Moliere's satirical remark, " II n'ya plus d'enfants," seems to be literally true at the present day. DISEASES OF SCHOOL-CHILDREN. The principal diseases incident to school-life are myopia, spinal deformities, nervous and digestive disorders, pulmonary phthisis, and contagious diseases. It is believed that by judi- cious sanitary measures these can all be very much diminished and some entirely prevented. It has been shown by the examination of the eyes of school- children that near-sightedness increases progressively from the lowest to the highest classes. Children who enter school with an hereditary tendency to myopia, or who are, perhaps, already near-sighted to a slight degree, soon become more intensely myopic ; while others, who may be even hypermetropic on enter- ing school, will be found to have become near-sighted during school-life. In examinations of over 30,000 pupils of grammar and high schools in Germany, Austria, Russia, and Switzerland, it has been found that the average proportion of near-sightedness is a fraction over 40 per cent., varying, in the different classes, from 22 per cent, for the lowest to 58 per cent, for the highest classes. These figures represent the averages of all the ex- aminations made. In some particular schools, for example in the gymnasium (high school) of Erlangen, the percentage in the higher classes was 88 per cent., in the gymnasium of Coburg 86 per cent., and in the gymnasium of Heidelberg the propor- tion of myopic students in the highest class is said to have reached 100 per cent, in 1877. In the primary schools the per- centage w r as found to be much lower. Recent investigations in the schools of Stockholm, by Widmark, show that among school-children examined under 7 years of age there was no 214 TEXT-BOOK OF HYGIENE. myopia. In the higher classes the myopia increases not only in degree, but in frequency. The diagrams, Figs. 20 and 21, show graphically the increase in degree and frequency of myopia in the several school-classes. These observations show that the number of myopic individuals bears a constant relation to the intensity of use of the visual organs. The results of the observation of different observers in different countries also J^epetraJt :...!---. ....--..-'--i . . ,.!_. ..... --i- .---. FIG. 21. MYOPIA ACCORDING TO SCHOOL-CLASSESGIRLS. should be used in text-books. That badly-arranged light and improper seats are causes of myopia has been shown by Flor- schutz in his examinations of the pupils in the public schools of Coburg. He found that in the newer schools, in which the light and seats are better arranged, the percentage of near-sight decreased. The average percentage of those examined in 1874 was 21, while in 1877 it had been reduced to 15, 2 showing 1 Erismann, Die Hygiene der Schule, in von Pettenkoffer und Ziemssen's Handbuch der Hygiene, II Tli., 2 Abtli.. p. 30. 1 Quoted by Colin in Realencyclopaedie d. ges. Heilk., Bd. XII, p. 263. 216 TEXT-BOOK OF HYGIENE. the great improvement due to the application of correct sanitary principles in the construction of school-houses. Defective hearing has recently been shown to be especially frequent among school-children. A Berlin aurist found 1392 children out of 5902 (23.6 per cent.) suffering from ear disease of some kind. Dr. Samuel Sexton, of New York, and the late Dr. Chas. F. Percivall, director of music in the public schools of Baltimore, have arrived at similar results after examination of a large number of school-children. Spinal curvature is present in a large proportion of the children attending schools. Statistics are not very full upon this subject, but one author, Guillaume, states that he found lateral curvature of the spine in 218 out of 731 school-children, a proportion of 29.5 per cent. This, of course, includes the slighter degrees of curvature, which cannot properly be termed a disease. Among 30,000 Danish school-children 13 per cent. had some variety or degree of spinal deformity. M. Eulen- burg 1 found that among 1000 persons with lateral curvature of the spine, the disease began in 887 between the ages of 6 and 14; that is to say, during the years of school-life. Girls are affected more than ten times as often as boys, the proportion being 93.43 per cent, in the former and only 6.57 per cent, in the latter. The especial causes of spinal curvature occurring during school-life are improperly-constructed seats and desks and an improper position of the body. Many pupils habitually assume a " twisted " position, which is very liable to produce spinal dis- tortion in children of weak muscular development. The manner in which a desk that is too high for the pupil may produce spinal distortion is very well shown in Fig. 22. An improper position is more likely to be unconsciously assumed by girls than by boys. The clothing is responsible for this, for when the girl files into her place behind the desk, her clothing, hanging loosely about her, is swept back and forms a pad, upon which 1 Realencyclopaedie d. ges. Heilk., Bd. XI, p. 5&4. DISEASES OF SCHOOL-CHILDREN. 217 she sits with one buttock. The greater elevation of her seat on that side throws the spinal column out of the vertical line, which is compensated by a partial twisting of the trunk. The attention of teachers should be directed to this faulty habit, which can be easily corrected, and its consequences averted by timely interference. Nervous disorders are comparatively frequent among school- children. Headaches are often due to insufficient ventilation, improper food, bad digestion, and excessive mental strain. Defective light may also be the cause of headaches by causing FIG. 22. SHOWING INFLUENCE OF A HIGH DESK IN CAUSING SPINAL CURVATURE. ocular fatigue. Hysterical and imitative affections are not infrequent, and sometimes pass through entire schools, including even the teachers. Girls are, of course, more subject to this class of disorders than boys, but the latter are not entirely exempt. Derangements of the digestive organs are exceedingly frequent among school-children. They can generally be traced to the use of improper food. The eating of cold lunches should be discouraged as much as possible. Nuts, candies, pies, fruit-cakes, and, above all, pickles are 218 TEXT-BOOK OF HYGIENE. most fruitful sources of digestive derangements of children. The absence of proper accommodations to enable children especially girls to answer the demands of nature are frequent sources of digestive and nervous disorders. The seeds of pulmonary consumption are frequently im- planted during school-life. A neglected cough ; bad ventilation, under which term may be comprised overheating and cold draughts, as well as polluted air; improper position of the body, excessive mental work, or underfeeding, may, any of them, be the starting-point of this fatal disease. Especial care should be taken to prevent the introduction or dissemination of contagious diseases through schools. The importance of this duty should be at all times impressed upon school-boards and teachers. In the first place, no child should be admitted within the door of the school-room unless it first presents undoubted evidence of protection against small-pox, either by having passed through a previous attack or by a proper vaccination. In case of an actual or threatened epidemic of small-pox the entire school, including teachers, should be vaccinated. Diphtheria has been shown to be frequently spread through the agency of schools. 1 This fatal disease demands especial precautions on the part of teachers and others involved in the management of schools, to prevent its introduction to these institutions. Children should not be admitted to school coming from a house where there is at the time, or has recently been, a case of contagious disease, such as small-pox, diphtheria, scarlet fever, or measles. At least four weeks should be allowed to elapse after the termination of such disease before a child from the infected house is re-admitted to the school. It goes without saying that no child having itself been sick with a contagious disease should be admitted to school until entirely restored to 1 The Relations of Schools to Diphtheria and to Similar Diseases, H. B. Baker, Public Health, vol. vi, p. 107. DISEASES OF SCHOOL-CHILDREN. 219 health. The aforesaid limit of four weeks is the briefest period allowable before the quarantine of the infected house (so far as the schools are concerned) can be relaxed. When a case of contagious disease has accidentally obtained entrance to the school, the pupils should be dismissed for the day, and the room thoroughly disinfected by means of sulphur, chlorine, or, what is better, scrubbing and spraying with solution of mercuric chloride. Teachers are not infrequently guilty of the grave impru- dence of sending pupils from the school to the house of an absent child to inquire the reason of the latter's non-appearance at school. It frequently happens that the absent child is sick, and the messenger is invited to the sick-room to see his or her class- mate. There can be no room for doubt that scarlet fever, diphtheria, and measles have often been introduced into schools in consequence of such thoughtlessness on the part of teachers. In order to promote the proper hygienic management of schools, all teachers should be required to submit to an exami- nation in the principles and practice of hygiene, at least so far as school hygiene especially is concerned. This is a demand that school-boards could reasonably insist upon, and there can be no question that the improvement in the health of the pupils would amply justify the innovation. [Students may consult with advantage the following special articles : D. F. Lincoln, School Hygiene, in Buck's Hygiene and Public Health, vol. ii, and Lomb Prize Essay on School Hygiene, Concord, N. H., 1887. F. Erismann, Die Hygiene der Schule, in Von Pettenkofer und Ziemssen's Handb. d. Hygiene, II, Th. 2 Abth. Reuss, Schulbank- frage, in Realencyclopsedie d. ges. Heilk., Bd. XII. H. Colin, Schul- kiuderaugen, ibid. C. J. Lundy, School Hygiene, Public Health, vol. ix. Rohe, The Necessity of the Sanitary Supervision of Schools, Journ. Am. Med. Ass'n, Dec. 28, 1889. Report of the Committee on School Hygiene to the American Medical Association, 1893.] QUESTIONS TO CHAPTER VIII. SCHOOLS. What does the hygiene of schools comprise? What principles are applicable in the construction of school-houses ? What is to be sought, and what avoided, in the selection of a site ? What should be the limit of height for school-houses ? What rooms are needed besides those for study or recitation ? What precautions must be observed regarding stairs, railings, and doorways ? How may the ground-air be kept out of the building? What kind of floors should the various rooms have ? What will be probably the best means of heating a school-house? What is the usual method in large schools ? Which will usualh' give the best ventilation, natural or artificial? When and how may school- rooms be ventilated to advantage ? How large should an ordinary school-room be? What are the advantages of a room of this size ? How many pupils would this accommodate, and about how much air-space would each have ? Is this sufficient? On which side of the room should the windows be, if possible? How should the seats and desks be arranged in relation to the windows ? What should be the relation of window-area to floor-area? How high should the windows be above the floor, and how near to the ceiling should they reach ? What are the objections to windows on two sides of the room ? Will windows of the above dimensions properly illu- minate the room ? How much artificial light will be needed for proper illumination? What should be the color of walls and ceilings? Where should the water-closets, etc., of a school be located? What supervision of these must be exercised ? How high should school-seats be? What should be the relation of seat to desk, and how high should the latter be ? Why should the front edge of the seat be brought under the desk ? How far should the black-boards be from the pupils ? On which side of the room ? How should the surface be finished? When should a child begin to go to school ? What is the maximum time advisable for daily study at the respective ages? What should be the length of lessons and recitations for each age ? What is an almost (220) QUESTIONS TO CHAPTER VIII. 221 certain result of too long study-hours ? Should there be more than one session daily, and should recesses be abolished ? What should form part of the daily school-routine ? Should this be taken from the recess period, or should it be part of the school-work ? What are some of the diseases incident to school-life ? Can these be prevented ? Are they altogether due to school-life ? How does the proportion of cases of near-sightedness vary in school-children ? Is the increase one of degree or of frequency ? What are the causes of this excess of myopia ? If these causes are avoided or corrected, will the prevalence of myopia decrease? What other sense is defective among school-children? What physical deformity is very prevalent ? What are the special causes of this deformity? Why is it apt to be more common among girls? At what age is the deformity most apt to begin ? What nervous disorders are frequent among school-children? What are some of the causes of chronic headache ? What pupils are most subject to hysterical affections? What are some causes of nervous disorders ? Of digestive disturbances ? How may consumption or other forms of tuberculosis be due to the school-life? What precautions should be observed in regard to the pre- vention of the spread of infectious diseases among school-children ? What diseases are to be especially guarded against, and how shall this be done? What should be the shortest limit of quarantine against a pupil that has had any one of these diseases? If a case of infectious disease gains entrance to the school, what is to be done ? Why should teachers be required to pass an examination on the principles of h} r giene ? CHAPTER IX. INDUSTRIAL HYGIENE. ONE of the most interesting chapters in the study of hygiene is that which treats of the relations of occupations to health and life. While it is unquestionable that certain occupations are intrinsically dangerous to health, there can be no doubt that in many instances incidental conditions not necessarily connected with the occupation are factors in the production of disease. Such factors are bad ventilation and other insanitary surround- ings, as well as in many cases want of sufficient or proper food. Occupations induce disease by compelling the workmen to inhale irritating, poisonous, or offensive gases, vapors, or dust ; or by causing the absorption through the skin or mucous mem- branes of irritating or poisonous substances. Changes of tem- perature, as exposure to great heat or cold, produce diseases which are, in some instances, characteristic. In another class of cases the excessive use of certain organs, as the nervous system, the eyes, the vocal organs, or various groups of muscles, produce characteristic morbid effects. Again, a constrained attitude while at work, a sedentary life, or occupations involving exposure to mechanical violence are recognized sources of dis- ease and death. The following table gives the mortality and average age at death of all decedents over 20 years of age whose occupation was specified, in the State of Massachusetts, for thirty-one years and eight months. The total number of decedents was 144,954; the average age at death, 50.90 years. Subdivided into classes and individual occupations, the results are as follow : (223) 224 TEXT-BOOK OF HYGIENE. TABLE XX. Occupations of Persons whose Occupations were specified, and whose Deaths were registered in Massachusetts during a period of thirty -one years and eight months, ending with December 31, 1874. 1 OCCUPATIONS. Number of Persons. Average Age at Death. OCCUPATIONS. Number of Persons. Average Ape at Death. CLASS I. Cultivators of the Earth: Farmers, Gardeners etc 31 832 65 29 Nail-makers .... Pail- and Tub- makers Painters ... 174 5 1 850 41.49 36.60 45 07 CLASS II. Active Me- chanics Abroad . 10,893 56 19 Paper-makers .... Piano-forte-makers . Plumbers ... . . 288 111 131 48.29 43.33 3553 Brick-makers .... Carpenters and Joiners Caulkers and Gravers 106 6,150 180 46.85 53.33 58 59 Potters Pump- and Block- makers 40 89 56.67 54.79 Masons ... 1 662 50 33 Reed-makers . 9 42 78 Millwrights 118 59 14 Rope-makers .... 248 58.05 RjcrcrfM-g . 161 52 25 Tallow-chandlers . . 67 54.93 Ship-carpenters . . . 873 58 53 Tinsmiths 375 41 05 Slaters 81 4099 Trunk-makers . . . 48 39.60 Stone-cutters 1,025 4090 ! Upholsterers .... 124 38.82 Tanners 537 50 36 ^Veavers 480 44 95 CLASS III. Active Me- chanics in Shops . . Bakers 16,576 471 47.57 47 04 Wheelwrights . . . Wood-turners .... Mechanics (not speci- fied) 507 76 2,015 56.98 52.07 44.84 Blacksmiths 2,402 5326 Brewers 28 47 11 CL vss IV. Inactive Cabinet-makers . . . Calico-printers .... Card-makers 781 9 39 48.84 52.11 48 23 Mechanics in Shops Barbers Basket-makers . . . 17,233 403 70 43.87 39.81 61 63 Carriage - makers and Trimmers . . 276 48 21 Book-binders .... Brush -makers 150 53 40.12 43 11 Chair-makers .... Clothiers ... 138 84 41.77 56 50 Carvers .... Ci^ar-makers 90 154 34.00 38 36 Confectioners .... Cooks . . .... 85 112 44.11 40 82 Clock - and watch- makers ... 100 5286 Coopers 927 59 22 Comb-makers . . 134 51 38 Coppersmiths .... 101 4589 Engravers 124 40.88 Curriers 366 41.50 Glass-cutters .... 76 43.16 Cutlers 131 39 21 Harness-makers . 423 48.74 Distillers 27 56 85 Jewelers . . 468 40 34 Dyers 143 45 17 2,138 39.16 Founders .... 361 42 51 Printers 717 38 62 Furnace-men .... 133 4342 Sail-makers . . . 217 5321 Glass-blowers .... Gunsmiths 132 250 37.88 48 86 Shoe-cutters .... Shoe-makers . . 362 9,772 42.94 44 61 Hatters 356 5467 Silver or Gold smiths 92 46.13 Leather-dressers 179 47 23 Tailors . ... 1,393 47 34 Machinists 2,097 41 67 Tobacconists .... 43 50.35 Millers 278 57 14 Whip-makers .... 99 42.63 Musical-Inst. mkrs. . 33 46.73 Wool -sorters .... 155 48.09 1 Thirty-third Registration Report of Massachusetts, p. cvi et seq. INDUSTRIAL HYGIENE. 225 TABLE XX (continued). OCCUPATIONS. Number of Persons. Average Age at Death. OCCUPATIONS. Number of Persons. Average Age at Death . CLASS V. Laborers (no special trades) . . . Laborers . . 28,058 27,382 389 76 193 18 7,035 37 246 537 4 327 17 567 216 9 10 417 81 2,885 354 1,282 24 22 8,844 433 4 58 82 8,267 15,977 376 49 151 75 73 198 3,435 255 47.41 47.49 40.10 52.09 5006 39.67 36.29 34.08 26.44 50.19 34.50 38.88 49.29 38.77 41.30 53.78 60.40 45.18 5994 2837 42.54 40.35 60.67 50.00 46.44 42.82 41.25 50.00 60.38 46.45 48.95 46.76 57.61 55.14 47.96 53 05 49.58 35.93 42.37 Gentlemen . . . 1,512 517 467 1,375 3,927 27 318 299 12 5 2,908 5,175 29 186 117 965 32 114 87 18 676 266 10 1,166 45 437 158 288 86 495 3,343 1,037 259 136 116 703 289 48 73 233 442 7 68.42 47.59 50.04 51.23 54.17 41.22 39.85 40.90 45.25 28.80 48.08 50.81 47.07 44.18 42.32 58.57 3731 41.61 46.68 64.11 56.45 41.59 36.80 54.99 55.93 55.37 53.76 23.23 51.44 41.79 39.13 46.64 43.36 39.42 61.06 27.82 46.50 43.12 3483 47.49 31.27 24.43 Grocers . . . Innkeepers . Servants Manufacturers . . . Merchants . . News-dlrs. and Car'rs R. R. Agents or Con- ductors .... Saloon- and Restau- rant- keepers . . . Stove-dealers .... Telegraphers .... Stevedores Watchmen . . . Workmen in Powder- mills CLASS V I . Factors Laboring Abroad, etc. Baggage-masters . . . Brakemen Butchers . . . CLASS IX . Profes- sional Men .... Architects Chimney-sweeps . . . Drivers Engin'rs and Firemen Expressmen . . . Artists Civil Engineers . . . Clergymen Lighthouse-keepers Comedians . ... Dentists Sextons Editors and Reprtrs. Judges and Justices . Lawyers Soldiers Stablers Teamsters . . . Musicians Photographers . . . Physicians Weighers and Gaugers Wharfingers CLASS VII. Employed on the Ocean .... Fishermen .... Professors . . . . Public Officers . . . Sheriffs, Constables, and Policemen . . Students . . . Marines Naval Officers .... Pilots . . .... Surveyors Teachers Seamen CLASS X. Females . Domestics CLASS VIII. Merch'ts, Mnanc'rs, Ag'ts, etc. Agents Dress-makers .... Milliners Bankers Nurses . ... Bank Officers .... Boarding-House kprs. Book-sellers . . Operatives . . . . Seamstresses .... Shoe-binders .... Straw-workers . . Tailoresses Brokers ... Clerks and Book-kprs. Druggists and Apoth- ecaries Teachers .... Telegraphers .... The above table cannot be absolutely relied upon for several reasons, the principal of which is that the table is incomplete. Many of the occupations are merely temporary, and persons are 226 TEXT-BOOK OF HYGIENE. constantly shifting from the pursuit of one calling to another Judges and lawyers, for example, should be included under one heading, while the class " students " should be excluded alto- gether. The table shows, however, very clearly, the relations of certain occupations to longevity. It is seen, for example, that agriculturists have the greatest expectation of life. Next to these come mechanics engaged out-of-doors. Professional men come next, and of these clergymen and members of the bar have the first and second places, respectively. The expectation of life of physicians is above the average, being nearly 55 years. Mechanics engaged in active work in-doors may expect to live 3.70 years longer than those whose occupation requires them to retain a more or less constant position. Occupations which are accompanied by the formation of much dust, either inorganic or organic, are especially unfavor- able. They usually produce diseases of the respiratory organs, which may eventuate in phthisis. In the table it is seen that the average age at death of stone-cutters was 40.90 ; of cotton-factory operatives male 39.16, female 27.82 ; l of cigar- makers, 38.36 ; and of cutlers, 39.21 years. The figures more or less closely approximate the conditions which have been shown to exist in England and on the Continent of Europe. In Sheffield, the workmen who grind and polish the cutlery, called " dry grinders," are said to suffer from a characteristic pulmo- nary affection termed "grinders' asthma" (emphysema) in the proportion of 69 per cent, of the whole number employed. The average duration of life of the needle-grinders of Derbyshire is 30.66 years. Among the cutlery-grinders of Solingen, in Hhenish Prussia, Oldendorff found 29 per cent, suffering from pulmonary affections, while the average age at death of the " dry grinders *' was 40.7 years. 1 These figures must be accepted with much reserve. While it is probable that the average age at death among women engaged in different occupations is less than that of men engaged in the same occupations, the figures in Table XX, Class X, cannot be used as a basis of comparison. So many women arc annually withdrawn from the various occupations by mar riage, which places them under different conditions, that the statistics of the occupations of women in the table are untrustworthy. OCCUPATIONS PREJUDICIAL TO HEALTH. 227 OCCUPATIONS PREJUDICIAL TO HEALTH. The diseases of occupations may conveniently be divided into the following classes : 1. Diseases due to the inhalation of irritating or poisonous gases and vapors. 2. Diseases due to the inhalation of irritating or poisonous dust. 3. Diseases due to the absorption or local action of irritating or poisonous substances. 4. Diseases due to exposure to elevated or variable temper- ature or atmospheric pressure. 5. Diseases due to excessive use of certain organs. 6. Diseases due to a constrained attitude and sedentary life. 7. Diseases from exposure to mechanical violence. I. DISEASES DUE TO THE INHALATION OF IRRITATING OR POISONOUS GASES OR VAPORS. Sulphurous-acid gas is used in various trades' as a bleach- ing agent. In the manufacture of straw hats and in the drying or " processing " of hops this agent is extensively employed, and the people engaged in these industries frequently suffer from respiratory and digestive disorders. These are, however, rarely serious. If free access of air is allowed, the dangers to health in the above employments are very slight. Nitric-acid fumes may be dangerous to health when in- haled in a concentrated form, but very few cases are on record where any positively deleterious influence can be traced to this agent. Hydrochloric-acid fames may prove deleterious to the work- men in soda manufactories, where the fumes are disengaged during the so-called " sulphate process." But the danger is probably slight. On the other hand, attention has recently been called to a peculiar effect of hydrochloric-acid fumes upon the workmen in fruit-canning establishments. The men who seal or " cap " the cans after being filled are the ones affected. The 228 TEXT-BOOK. OF HYGIENE. lesion has been described by Dr. W. Stump Forwood, who says concerning it : " The constant inhalation of the fumes of muri- atic acid, associated as they are with the lead solder, which the busy " capper " neglects to protect himself against, soon pro- duces inflammation of the mucous membrane of the nose, which finally results in ulceration. With some patients, after the removal of the cause and the application of proper treatment, recovery takes place after two or three months ; but with those who have a scrofulous taint in their constitutions this ulceration is exceedingly intractable, and, in spite of all treatment, proceeds for months and even years, until the septum is finally perforated. And, strange to say, it is the common experience of those who have suffered that, as soon as perforation takes place, all the soreness and consequent annoyance disappears and the patient recovers, with, of course, a permanent opening in the nasal septum." l Dr. Forwood adds that anointing the nose, both within and without, several times a day, and avoidance of the acid fumes as much as possible, will prevent the peculiar affection. Ammonia rarely causes disturbances of health in work- men brought into contact with it. AVhen present in the air in large* proportion it may give rise to serious symptoms. As it is often used to prevent the poisonous effects of mercury (q. v.), care should be taken that the proportion of the vapor in the air of the work-room should not exceed 5 per cent. Chlorine gas is very deleterious in its effects upon the work- men brought in contact with it in the various industries in which it is employed. Nearly one-half of the workmen engaged in the manufacture of chlorinated lime and in bleaching become affected. The respiratory organs are principally attacked. Pneu- monia is exceptionally frequent. If an affected individual is predisposed to consumption the latter disease is soon lighted up, and quickly proves fatal. The effect of the inhalation of con- centrated chlorine is thus graphically described by Hirt 2 : " The iPhila. Med. and Surgical Reporter, June 30, 1883. * Von Pettenkofer und Ziemssen's Handbuehder Hygiene, etc., II Th., 4 Abth., p. 30. DISEASES DUE TO INHALATION OF GASES OR VAPORS. 229 workman suffers from violent cough and extreme dyspnoea. In spite of the aid of the auxiliary respiratory muscles, the entrance of air to the lungs is insufficient, and the widely-opened eyes, the pale-bluish color, and the cold perspiration plainly show the mortal agony of the patient. With this the pulse is small, the temperature decreased. Soon after removal from the impreg- nated atmosphere these phenomena disappear, and a few hours later the workman is found enveloped in chlorine and hydro- chloric-acid vapors in his accustomed place in the factory. The attacks seem to be but rarely fatal." The constant inhalation of an atmosphere strongly impreg- nated with chlorine produces a cachectic appearance, bronchial catarrh, loss of the sense of smell, and a prematurely aged appear- ance. When this stage of chronic chlorine poisoning has been reached complete health can rarely be re-established, even if the patients be entirely removed from the irritating atmosphere. Carbon monoxide is often present in the air of gas-works, iron smelting-works, and coke or charcoal furnaces. The work- men engaged in these industries often suffer with diseases of the respiratory organs, digestive disturbances, and general debility. Acute poisoning from carbon monoxide is relatively frequent, as already pointed out. 1 The prominent symptoms are at first vio- lent headache, dizziness, and roaring in the ears. These symp- toms are followed by great depression of muscular power, nausea, and vomiting. The vomited matters sometimes gain entrance into the trachea, and may thus produce strangulation. Uncon- sciousness, convulsions, and asphyxia rapidly succeed. Paral- yses of the sphincters and of groups of other muscles are often present. The pulse is at first somewhat increased, but soon becomes slower. The respiration is slow and stertorous, and tho temperature falls from 2.5 to 3 C. (3 to 4 F.). Glycosuria often occurs. If death does not occur in the attack, the patient fre- quently suffers from great depression, both physical and mental; loss of appetite, constipation, and various paretic conditions. 1 See Chapter I, p. 29. 230 TEXT-BOOK OF HYGIENE. The slow or chronic form of poisoning by carbon monoxide is characterized by headache, dizziness, slow pulse and respira- tion, nausea, and sometimes vomiting and purging. Loss of memory and diminution of mental activity are also said to be effects of the continued inhalation of air charged with carbon monoxide. Carbon dioxide is found as one of the constituents of the "choke-damp" in mines. There is reason to believe that this is often the source of ill health and death in miners, even where the symptoms of acute carbon-dioxide poisoning are not present. Hon. Andrew Roy 1 says that "it is more insidious than direct in its operations, gradually undermining the constitution and kill- ing the men by inches." Difficulty of respiration and weakness are the only symptoms calling attention to the pernicious effects of the gas. Where, however, the proportion of carbon dioxide is large, acute poisoning occurs. This is manifested by the following symptoms : Loss of consciousness and of the power of voluntary motion. In some cases there are convulsions ; in others the above symptoms are preceded by difficult respiration, headache, depression, drowsiness, or psychical excitement. Re- covery usually soon follows after removing the patient into a purer atmosphere. Vintners, distillers, brewers, and yeast-makers are said to suffer from the effects of carbon dioxide occasionally, but serious results from this cause are probably very infrequent. It may not be amiss to call attention here to another dan- gerous mixture of gases sometimes found in mines, and which is occasionally the source of appalling accidents. This is the so-called "fire-damp" or light carburetted hydrogen (CH 4 ). When this gas is mixed with atmospheric air in the proportion of 6 to 10 volumes per cent, the mixture becomes violently explosive if ignited. The danger does not cease with the explo- sion, however, for in this act the free oxygen present is consumed 1 Third Annual Report State Mine Inspector of Ohio. Quoted in Buck's Hygiene and Public Health, vol. ii, p. 243. DISEASES DUE TO INHALATION OF GASES OR VAPORS. 231 in the formation of carbon dioxide, and the workmen then die asphyxiated, or from the effects of "choke-damp." The dangers from "fire-damp" can be largely averted by thorough ventilation and by the use of the safety-lamp of Sir Humphry Davy, which gives warning of the presence of the gas and permits the work- men to escape before the explosion takes place. Sulphuretted hydrogen, when present in the air in large proportion, as, for example, in privy-vaults, cess-pools, and sewers, may produce serious or fatal poisoning. Formerly, when vaults were cleaned in the primitive way, these accidents were frequent; but at the present day, owing to improved methods of removing excreta, they are comparatively rare. The precautions advised in a preceding chapter 1 should be borne in mind when it is necessary for workmen to enter such places. The gases resulting from the putrid decomposition of organic substances, such as are found in tanneries, glue- and soap- works, and similar, industries, are popularly believed to give rise to various diseases. There are no observations on record, however, to show that such is the case. As a matter of fact, the workmen engaged in the industries mentioned, seem to be exceptionally healthy, and to resist to a considerable degree the ravages of phthisis and epidemic diseases. Bisulphide of carbon is used in the arts principally in the process of vulcanizing India rubber, and for extracting oils from seeds and fatty bodies. The constant inhalation of the vapor of bisulphide of carbon produces a train of symptoms to which attention was first attracted by Delpech in 1856. The symp- toms have been observed frequently since that time. The follow- ing account is from Hirt 2 : " Some days, or even weeks or months, after beginning this occupation, the workmen complain of a dull headache, becoming more severe toward evening. This symptom is soon followed by joint-pains, formication, and itching on various parts of the body. A more or less troublesome cough is present, but is not accom- 1 Chapter I, p. 37. * Op. cit., p. 66. 232 TEXT-BOOK OF HYGIENE. panied by any characteristic sputa. The respiration is regular, the pulse somewhat increased in frequency. During this time certain individuals exhibit a marked exaltation of their intel- lectual powers; they talk more than formerly, and show an interest in matters in which they at other times show no concern. There is, however, very rarely distinct mental disease. The sexual desires are increased in both sexes, menstruation becomes irregular, and the urine possesses a faint odor of bisulphide of carbon. In this manner several weeks or months pass away. Very gradually the psychical exaltation disappears, and a pro- found depression, melancholy, and discouragement succeeds, coupled with which is often loss of memory. Vision and hear- ing become less acute, and the sexual activity is completely destroyed. Anaesthetic spots appear on various parts of the body, and numbness of the fingers prevents the workman from perform- ing any fine work." The disease never proves fatal, but the normal condition of the individual is rarely re-established when the disorder has advanced to the extreme stages mentioned. Iodine and bromine vapors, when inhaled by workmen en- gaged in their preparation, produce symptoms of poisoning which are sometimes very serious. Acute iodic intoxication consists in severe laryngeal irritation, headache, conjunctivitis, and nasal catarrh. Occasionally there is temporary loss of con- sciousness. Chronic iodic cachexia is often found among the workmen. In certain cases atrophy of the testicles and gradual disappearance of sexual power has been observed. In the manu- facture of bromine, a form of bronchial asthma has been observed among those engaged in the establishment. No symptoms corresponding to those of chronic iodism have been observed among the workmen in bromine. The inhalation of the vapors of turpentine produces, in a considerable number of those constantly exposed to them, dis- eases of the respiratory organs, beginning with cough and, at times, resulting in consumption. In other cases derangement DISEASES DUE TO INHALATION OF GASES OR VAPORS. 233 of the digestive organs, strangury, and, in a few cases, bloody urine have been observed. Nervous disturbances are rare after the inhalation of turpentine, and are limited to headache, roar- ing in the ears, or flashes of light before the eyes. Petroleum vapor, when inhaled in a concentrated state, pro- duces symptoms similar to those of anaesthetics. When exposed for a long time to diluted petroleum vapor, workmen sometimes suffer from chronic pulmonary catarrhs or from nervous de- rangements. Among the latter are disturbances of mental activity, loss of memory, giddiness, and headache. These symp- toms are, however, rare. More frequent are pustular or furuncu- lar affections of the skin, which are due probably to the direct irritant effect of the vapor. Lead poisoning is one of the most characteristic diseases of artisans. It attacks workmen engaged in the roasting and smelt- ing of lead ores ; in the manufacture of white and red lead and of lead acetate and chromate ; in type-making, in painting, and, in short, in all occupations in which the workman is compelled to inhale the vapor or dust of lead, or in which it is conveyed in some manner to the digestive organs. It is believed also that it can be absorbed by the skin and produce its poisonous effects upon the economy. The average duration of life in the roast- ing and smelting furnaces is 41 years ; of painters, as shown by Table XX, 45.07 years. Of the latter 75 per cent, are attacked by one of the forms of lead poisoning, colic being most frequent. In the manufacture of white lead more than half of the work- men suffer from lead poisoning during the first year, lead colic being present in 60 per cent, of all the cases. In most sugar-of-lead manufactories 60 per cent, of all the operatives constantly suffer from some form of lead poisoning. Poisoning has also been observed in workmen engaged in the manufacture of various pigments of which the acetate of lead is the base (e.g., lead chromates). Among type-founders the symptoms of lead poisoning are not very rare, and even 23-t TEXT-BOOK OF HYGIENE. compositors sometimes suffer from lead poisoning. In the latter case the lead must be absorbed through the skin in order to produce its effects. The various forms in which lead poisoning affects the indi- vidual are the lead cachexia, manifested by loss of weight, dis- coloration of the skin, the characteristic blue line along the gums, diminution of the salivary secretion, a sweetish taste, and offensive odor of the breath ; then lead colic, the features of which are well known ; lead paralysis, the characteristic " wrist- drop," which requires prompt and intelligent treatment, other- wise permanent atrophy of the affected muscles often takes place. Among other nervous manifestations of the poison is a painful affection of the lower extremities, attacking joints and flexor muscles, and remittent in character. At times anaesthesia of the skin of the head and neck is present. In rare cases serious mental derangement occurs. Other grave nervous lesions, such as the so-called saturnine hemiplegia and tabes, are happily extremely rare among the workmen in the metal at the present day. Mercurial poisoning is frequent among the artisans who work in the metal. The smelters of the ore suffer severely and in a large proportion of the entire number employed. Their average age at death is 45 years. Mirror-makers suffer most severely of all the artisans who come in contact with the vapors of the metal. It is beyond question that the confinement in badly-ventilated work-rooms is largely responsible for the poi- sonous effects of the metal upon this class. The special forms in which the poisonous effects are manifested in mirror-makers are salivation, mercurial tremor, and nervous erethism, but, in addition, a very large proportion surfer from pulmonary con- sumption. It is stated that 71 per cent, of the total deaths among mirror-makers (those who coat the glass with the mer- curial alloy) are from phthisis. Among women the symptoms are aggravated, and abortion frequently occurs. Of the children of women suffering from DISEASES DUE TO INHALATION OP GASES OR VAPORS. 235 mercurial poisoning born living at term, 65 per cent, die within the first year. In the Almaden quicksilver mines in Spain a considerable proportion of the workmen suffer from the milder symptoms of mercurial intoxication (gingivitis, salivation, or dryness of the mouth). The more severe manifestations (tremor, convulsions, contractures, violent muscular pains, paralysis, cachexia) are much less frequent, and latterly not so severe as they were formerly. Fire-gilders, fulminate- makers, and physical instrument- makers not infrequently suffer from the deleterious effects of inhaling the vapor of mercury. Hatters are also liable, to a considerable extent, to the poisonous effects of the metal. 1 It has been found that upon sprinkling the floor of the work-room of mirror-makers with aqua ammonia, so as to im- pregnate the atmosphere with ammonia, the bad effects of mer- cury on the system are markedly diminished. Care must be taken, however, not to use the ammonia to excess, otherwise the diseases caused by this agent may attack the workmen. Zinc or copper vapors, or possibly a combination of the two, given off from the brass, which is an alloy of these metals, produces a peculiar train of symptoms known as "brass- founders' ague." The symptoms are described by Hirt, who has suffered from two attacks of the affection himself, as fol- lows 2 : "A few hours after attending the process of brass- casting, one notices a peculiar, uncomfortable sensation over the whole body. More or less severe pains in the back and gen- eral lassitude cause a discontinuance of the ordinary occupa- tion. While the pains appear now here, now there, and are extremely annoying, no changes in the pulse or respiration are noticeable. In a short time, however, usually after the patient has taken to the bed, chilliness comes on, which soon increases to a decided rigor, lasting fifteen minutes or longer. In the i Hatting as Affecting the Health of Operatives, L. Dennis, Report New Jersey State Board of Health, 1879 ; Connecticut State Board of Health, 1883. * Op. cit., p. 122. 236 TEXT-BOOK OF HYGIENE. course of an hour or less the pulse now reaches a rapidity of 100 to 120 beats per minute. A tormenting cough, combined with a feding of soreness in the chest, comes on. In conse- quence of the repeated acts of coughing, the increasing frontal headache produces exceeding discomfort. Soon, however, usu- ally after a few hours, the height of the attack is reached ; free perspiration indicates the stage of defervescence, and during the gradual diminution of the symptoms the patient falls into a deep sleep, lasting several hours. On awakening, a slight headache and lassitude only remain as reminders of the attack." It is said that about 75 per cent, of the workmen in brass- foundries are attacked by this affection ; the attack is liable to be repeated at every exposure. A chronic form of poisoning is said to occur among zinc- smelters after following their occupation for ten to twelve years. It consists of hyperaesthesia, formication, and burning of the skin of the lower extremities, soon followed by alteration in the temperature and tactile sensation, and diminution of the mus- cular sense. Paresis of the lower extremities sometimes comes on. The disease has not yet been sufficiently investigated. Aniline vapor is exceedingly poisonous when inhaled in a concentrated state. Hirt describes an acute form which usually results fatally : " The workman falls suddenly to the ground ; the skin is cold, pale ; the face is cyanotic, the breath has the odor of aniline, the respiration is slowed, and the pulse increased. The sensation, diminished from the beginning of the attack, gradually entirely disappears, and death follows in a state of deep coma." 1 There is a milder form which comes on after several days of exposure. It is characterized by laryngeal irritation, diminution of appetite, headache, giddiness, great weakness, and depression. The pulse is rapid, small, and irregular. Respiration is little altered. There is decrease of sensibility of the skin. Convulsions may occur, but are usually of short duration. 1 Op. oil., p. 127. DISEASES DUE TO INHALATION OF DUST. 237 The chronic form of aniline poisoning is characterized by three sets of symptoms : those affecting the central nervous system, the digestive tract, and the skin. Among the first are lassitude, headache, roaring in the ears, and disturbances of sensation and motion of greater or less degree. The digestive derangements consist in eructations, nausea, and vomiting. The cutaneous lesions are eczematous or pustular eruptions, and sometimes round, sharply-circumscribed ulcers with callous borders. There is no trustworthy evidence that in the manufacture of aniline colors poisonous symptoms are produced in the workmen. II. DISEASES DUE TO THE INHALATION OF IRRITATING OR POISONOUS DUST. The inhalation of air containing particles of organic or inorganic matter has long been accepted as a cause of certain special diseases of artisans. The diseases so caused are usually limited to the pulmonary organs, and consist of acute and chronic catarrh, emphysema of the lungs, pneumonia, interstitial inflammation of the lungs, the so-called fibroid phthisis or pul- monary cirrhosis. Coal-dust is inhaled by coal-miners, charcoal-burners, coal- handlers, firemen, chimney-sweeps, foundry-men, lead-pencil makers, etc. Chronic bronchial catarrhs are most frequent, while phthisis and emphysema are almost absent from the list of diseases affecting these workmen. Dr. W. B. Canfield has reported an interesting case of pneumonoconiosis in which there was coincident bacillary phthisis. 1 The table on page 208 shows that the expectation of life of foundry-men, furnace-men, fire- men, and chimney-sweeps is much below the average. Metallic dust is inhaled by blacksmiths, nailers, cutlers, lock- smiths, file-cutters, cutlery- and needle- polishers, etc. While 1 Trans. Med. and Chir. Fac., Md., 1889. 238 TEXT-BOOK OF HYGIENE. in this class of workmen cases of bronchitis and pneumonia are relatively frequent, much the largest proportion suffer from phthisis. A table compiled by Hirt shows that out of the total number of sick in the different classes of workmen the cases of phthisis were : 62.2 per cent, for file-cutters, 69.6 " " needle-polishers, 40.4 " " grinders, 12.2 " " nailers. The Massachusetts table gives the average duration of life for blacksmiths at 53.26 years, of nail-makers at 41.49 years, and of cutlers at 39.21 years. The needle-polishers at Sheffield, as already stated (page 210), have only an average duration of life of 30.66 years. In this work and that of grinding knivesj scissors, and similar articles, the metallic dust is mixed with mineral dust (particles of silica from the grindstone). This mixture seems to be much more deleterious than metallic dust alone, as shown by the shorter average duration of life and the enormous percentage of cases of consumption. Mineral dust is inhaled by the workmen in a large number of different industries. The grinders in the ground-glass factories suffer most severely. Hirt found the average duration of life in grinders who began this occupation after their 25th year to be 42.50 years, while in those who began at the age of 15 the average duration w r as 30 years. Millstone cutting is also a very dangerous occupation. Pea- cock 1 gives the average age of these workmen at 24.1 years. Stone-cutters generally suffer frequently from phthisis, probably largely in consequence of the constant inhalation of the mineral dust produced during their work. The Massachusetts table gives the average age at death of these workmen at 40.90 years, while Hirt's table gives a much lower age, namely 36.3 years. Potters and porcelain-makers are exposed to similar dangers from their occupation, but to a much less degree. The table on 1 Quoted by Merkel, in von Pettenkof er und Ziemssen's Handbuch der Hygiene, II Th., 4 Abth., p. 197. DISEASES DUE TO INHALATION OF DUST. 239 page 208 gives the average age at death at 56.67 years, rather a high average. Slaters and workmen in slate-quarries suffer in a large pro- portion of cases from chronic pneumonia, and die at a compara- tively early age. Masons and carpenters have an average duration of life of 50.33 and 53.33 years, respectively. One-third of all the diseases from which they suffer affect the respiratory organs. Gussenbauer has reported a very interesting series of cases of a peculiar inflammatory affection of the diaphyses of the long bones in the artisans who are engaged in the manufacture of pearl buttons. Gem-finishers are exposed not .only to the inhalation of dust, but to poisonous gases (carbon monoxide) and vapors (lead). The proportion of sickness among them is very high. Vegetable Dust. The workmen compelled to inhale vege- table dust are those who work in tobacco, cotton-operatives, flax-dressers, paper-makers, weavers, wood-turners, millers, and laborers in grain-elevators. Workmen in tobacco usually suffer, within a few weeks after beginning work, from a nasal, conjunctival, and bronchial catarrh, which soon passes off, as the mucous membranes seem to become accustomed to the irritation. Nausea is also frequent at first, due probably to the absorption of small quantities of nicotine. Females exposed to tobacco-dust usually suffer from digestive and nervous troubles. They are also said to abort frequently. Dr. R. S. Tracy, 1 as a result of his observations among cigar-makers in New York, states that the fecundity of these people is much less than the average. Three hundred and twenty-five families visited had only 465 children, an average of 1.43 to each family. Dr. Tracy is inclined to attribute this to the frequent abortions that occur among the females exposed to the inhalation of tobacco-dust. According to the Massachusetts 1 Buck's Hygiene and Public Health, vol. ii, p. 62. 240 TEXT-BOOK OF HYGIENE. table, cigar-making is an unfavorable occupation, the average age at death being 38.36 years. Cotton-operatives, flax-dressers, weavers, and workmen in paper-mills are Subject to various diseases of the respiratory organs. Coetsem, as long ago as 1836, described a peculiar pulmonary affection among cotton-operatives, which he termed pneumonic cotonneuse. The observation does not seem to have been verified by others ; at all events, the author is unable to find any other record of a similar affection in the literature of the subject. Among weavers the mortality from phthisis is comparatively high. Among paper-makers Hirt found an average duration of life of 37.6 years. The people who sort rags are liable to a fatal infectious disease, " rag-sorters' disease" (Hademkrankheit 1 ), which resembles in all respects, and is prob- ably nothing less than, anthrax. No cases have been reported in this country, but, as the importation of rags from abroad is carried on to a considerable extent, no apology is believed to be necessary for calling attention to it. The " wool-sorters' disease," to which attention has recently been called in England, is doubt- less similar in its nature. Millers suffer in a large proportion of cases from pulmonary affections, especially bronchial catarrh and pneumonia. Accord- ing to Hirt, 20.3 per cent, of all the diseases of these workmen are pneumonias, 9.3 per cent, bronchial catarrhs, 10.9 per cent, phthisis, and 1.9 per cent, emphysema. The average duration of life is 45.1 years. The Massachusetts table gives 57.14 years, a very much more favorable exhibit. The laborers in grain-elevators are compelled to inhale a very irritating dust, which causes acute and chronic catarrhs of the respiratory organs. Dr. T. B. Evans, of Baltimore, has reported a series of cases of catarrhal pneumonia in these work- men, which were characterized by some very peculiar features. Brush-making, according to the statistics of Hirt, is a very dan- gerous occupation. Nearly one-half of the deaths among brush- f 1 See article by Soyka, Realencyclopaedie d. ges. Heilk, Bd. VI, p. 165. DISEASES DUE TO POISONOUS SUBSTANCES. 241 makers are from phthisis, due, in great measure, to the inhalation of the sharp fragments of bristles produced in trimming the brushes. In the Massachusetts table the average duration of life is given at 43.11 years. III. DISEASES DUE TO THE ABSORPTION OR LOCAL ACTION OF . IRRITATING OR POISONOUS SUBSTANCES. Arsenic is used in the manufacture of green pigments and for various other purposes in the arts. In the preservation of furs and in taxidermy it finds extensive use. In the prepara- tion of the pigment known as Paris green the workmen are frequently entirely covered by a layer of the poisonous salt. The poisonous symptoms occur in consequence of the absorption of the poison through the skin or from its local action, and but rarely on account of inhalation of vapors or dust in which it is contained. The most marked symptoms are chronic gastric catarrh, superficial erosions in the mouth, dry tongue, thirst, and a burning sensation in the throat. Tljese symptoms may con- tinue for months, or even years, and gradually produce a com- plete breaking down of nutrition and the vital powers. Violent itching skin eruptions of an eczematous character are not infre- quent complications of the internal symptoms. Lewin has described a localized pigmentation of the skin in workmen (engravers) in silver. The left hand is especially affected. The occurrence of the affection is explained by the numerous slight injuries of the hands by the graver's tools and the local absorption and decomposition of the silver. Phosphorus produces two classes of effects in persons sub- jected to its influence. The milder effects are produced by the inhalation of the fumes of the substance, and are limited to digestive disturbances and diseases of the pulmonary organs. The severer symptoms are only observed among the employes in match-factories, and are due to the local action of the phos- phorus upon the tissues affected. The characteristic disease produced by phosphorus is a 10 242 TEXT-BOOK OF HYGIENE. painful periostitis of the lower or upper jaw. The limitation of the affection to this locality is believed to be due to the action of the phosphorus dissolved in the saliva. The fact that the lower jaw, with which the saliva comes more thoroughly in contact, is most frequently affected seems to indicate that this view is the correct one. The disease begins, on an average, five years after the beginning of the employment. Hirt estimates the proportion of employes in match-factories attacked at 11 to 12 per cent. The first symptom of the disease is toothache, soon extending to the jaw. The cervical glands swell up ; the gums become reddened and spongy ; abscesses form about the diseased teeth, from which large quantities of thin, offensive pus are discharged. Examination with a sound reveals carious, nodulated bone. The cheeks become swollen, erysipelatous, and may suppurate and discharge pus externally. Hutchinson has reported a case in which the long-continued internal administration of phosphorus as a medicine produced maxillary necrosis. The destruction of the soft tissues continues until resection of the jaw. is finally undertaken and the disease checked by surgical interference, and removal of the patient from the influ- ence of the pernicious substance. Dr. J. Ewing Mears reports 1 16 cases of phosphorus ne- crosis. He concludes " that the antidotal powers of turpentine have been established, both in neutralizing the effects of the poison upon operatives during their work and also in the treat- ment of the early stage of the disease. The disease is to be prevented by the adoption of thorough methods of ventilation, stringent rules with regard to cleanliness, and the free disen- gagement of the vapors of turpentine in all the apartments of factories in which the fumes of phosphorus escape." In the manufacture of quinine a troublesome eczema is caused in about 90 per cent, of the employes. It seems to be due to emanations given off from the boiling solutions. It 1 Trans. Am. Surg. Association, 1887. DISEASES DUE TO ELEVATED OR VARIABLE TEMPERATURE. 243 begins with intense itching, followed by swelling and the forma- tion of vesicles, which soon burst and form crusts. There is considerable fever when the swelling is great. It is said that blondes are more frequently affected than those of dark com- plexion. The disease soon disappears if the work is given up. The workmen engaged in the manufacture of bichromate of potassium are said to suffer from an ulceration of the nasal mucous membrane very similar to that already described as due to the vapors of hydrochloric acid (p. 212). Rapidly spreading, deep ulcers are also said to form if the bichromate comes in contact with abraded surfaces of the. skin. The strong alkali handled by tanners frequently produces fissured eczemas of the hands, which are painful and often diffi- cult to cure. The workmen in petroleum refineries frequently suffer from acneiform or furuncular eruptions. Among glass-blowers, syphilis is frequently communicated by an infected mouth-piece which is used by the men in turn. IV. DISEASES DUE TO EXPOSURE TO ELEVATED OR VARIABLE TEMPERATURE OR ATMOSPHERIC PRESSURE. Cooks and bakers are exposed almost constantly to a high temperature, which produces an unfavorable influence upon health and predisposes them to diseases of various kinds. The Massachusetts table shows that cooks have a much shorter duration of life than bakers, although the statistics of both trades are unfavorable. The prevailing diseases among cooks and bakers are rheu- matism and eczematous eruptions, generally confined to the hands, forearms, and face. Blacksmiths, founders, and firemen suffer from the intense heat to which they are exposed, in addition to the inhalation of coal-dust, as has already been pointed out. The stokers in the engine-rooms of steam-ships suffer especially from the excessively high temperature to which they are subjected by their occupation. 244 TEXT-BOOK OF HYGIENE. A form of heart-weakness, described by Levick as " fireman's heart," is prevalent among them. Sailors, farmers, coachmen, car-drivers, and teamsters are subjected to stress of weather, changes of temperature, and storms. They surfer frequently from rheumatism, acute bron- chitis, pneumonia, and Bright's disease. Car-drivers are said also to surfer from painful swelling of the feet, varicose veins and ulcers, and mild spinal troubles. 1 Sun-stroke is not confined to any class of artisans, but persons who perform very hard labor, especially in a confined atmosphere, suffer most frequently. The effects of compressed air on workmen in tunnels and deep mines has already been referred to. 2 The most serious symptoms occur not when the individual is subjected to the increased pressure, but when the pressure is too rapidly dimin- ished. V. DISEASES DUE TO THE EXCESSIVE USE OF CERTAIN ORGANS. The prevalent belief that the overuse of the intellectual faculties is a frequent cause of mental disease is not borne out by facts. Men and women who perform an amount of mental work regarded by most persons as excessive have, in spite of this, a long duration of life. There are no exact statistics upon this subject, but Caspar, half a century ago, made the following estimate of the average duration of life among professional men : Clergymen live 65; merchants, 62.4; officials, 61.7 ; lawyers, 58.9 ; teachers, 56.9, and physicians, 56.8 years. In the table on page 209 the figures are somewhat less favorable, although corresponding in general with those of Caspar. Hence, it is seen that, of professional men, those whose occupation compels the exercise of high mental powers have a higher duration of life than any other class, except farmers and mechanics engaged actively out of doors. ' Those professional occupations only which necessitate a more or less irregular mode of life and 1 A. McL. Hamilton in Report New York Board of Health, p. 444, 1873. * Chapter I, p. 12. DISEASES DUE TO A SEDENTARY LIFE. 245 frequent subjection to physical exhaustion and dangers- from contagious disease, such as the work of physicians and journal- ists, make an unfavorable showing in the statistics. The prop- osition may be laid down that it is not mental activity, however great, but mental worry that tends to the abbreviation of life. The occupation of a tea-taster is said to produce a peculiar nervous condition, manifested in muscular tremblings, etc., which compels the individual to give up the work in a few years. Persons who test the quality of tobacco, an occupation corre- sponding to that of tea- taster, are said to suffer from nervous symp- toms, which may include amaurosis and other grave affections. Those persons who are compelled to use their eyes con- stantly upon minute objects frequently suffer from defective vision. So engravers, watch-makers, and seamstresses are liable to near-sightedness, amaurosis, and irritation of the conjunctiva. Public speakers and singers frequently suffer from catarrhal or even paretic conditions of the throat, which usually disappear on relinquishing the occupation for a time. Telegraph operators and copyists suffer from a peculiar convulsive affection of the fingers, called " writers' cramp." Cigar-makers are also said to suffer from a similar cramp of the fingers used in rolling cigars. Performers on wind instru- ments are liable to pulmonary emphysema, on account of the pressure to which the lungs are frequently subjected. Boiler- makers often suffer from deafness, .in consequence of their constant existence in an atmosphere in a state of continual violent vibration. The affection is generally recognized as " boiler- makers' deafness." Dr. C. S. Turnbull has reported several cases of " mill-operatives' deafness." Its characteristic is an inability to hear distinctly except during a noise. VI. DISEASES DUE TO A CONSTRAINED ATTITUDE AND SEDENTARY LIFE. It* is probable that the large mortality and morbility rate of persons whose occupations keep them confined within doors 246 TEXT-BOOK OF HYGIENE. are due, next to the defective ventilation, to the constrained attitude which most of them necessarily assume. Thus, carvers, book-binders, engravers, jewelers, printers, shoe-makers, book- keepers, and cigar-makers all have a low average duration of life.' It is found, likewise, that many of these artisans suffer most from pulmonary and digestive troubles, among the former being phthisis, and among the latter constipation, dyspepsia, and haemorrhoids. VII. DISEASES FROM EXPOSURE TO MECHANICAL VIOLENCE. It will be seen, by reference to the table on page 209, that all persons whose occupations involve an intimate contact with machinery, and in the pursuit of which accidents frequently happen, have a short duration of life. Persons liable to these dangers are machinists, operatives in factories, workmen in powder-mills, baggage-masters, brakemen, drivers, engineers, firemen, and other workmen on railroads. Aside from the diseases to which some of these classes are liable in consequence of exposure to variable atmospheric conditions, the grave acci- dents to which they are so frequently exposed render their occupations extremely dangerous. Brakemen on freight rail- roads, for example, are classed by insurance companies as the most hazardous " risks," and some companies refuse to take them at all. The table on page 209 tends to confirm the conclusion of the insurance companies, for, excluding the class of " students," which, for manifest reasons, cannot be used as a comparison, brakemen have the shortest average duration of life of all the occupations noted in the table. [The student is referred, for more complete information on the subjects considered in the foregoing chapter, to the following works : L. Hirt, Die Krankheiten der Avbeiter. Eulenburg, Handbuch der Gewerbehygiene. Layet, Hj'giene des Professions et des Industries. Arlidge, The Diseases of Occupations.] QUESTIONS TO CHAPTER IX. INDUSTRIAL HYGIENE. How may various occupations induce disease? Are such diseases always necessarily due to the occupations, or are there incidental factors that might be avoided? What classes of men have the greatest expecta- tion of life? What occupations are especially unfavorable to health? What diseases do they usually produce? How may diseases of occupa- tions be conveniently classified? What disorders are liable to be produced by the inhalation of the gases of the mineral acids? What peculiar symptoms may be due to the constant inhalation of the fumes of hydrochloric acid? What effect has ammonia gas? What disease is frequently due to the constant inhalation of chlorine gas? What other disease is also especially favored by it? What are some of the symptoms produced by the gas in a concentrated state ? By the constant inhalation of the gas ? In what occupations is carbon monoxide often given off to the air? What are some of the acute symptoms produced by it ? What of the chronic poisoning by the gas ? Is there any evidence that carbon diox- ide in small amounts may cause symptoms of chronic poisoning? What are some of the manifestations in cases of acute poisoning by this gas ? What other gas is often found in mines, and how may it be dangerous to life ? How may its dangers be avoided ? Where may sulphuretted hydrogen be found in quantities sufficient to produce serious results? What are some of the evil effects due to the inhalation of the vapor of bisulphide of carbon? Of iodine and bro- mine? Of turpentine? Of petroleum? In what occupations are the laborers subject to lead poisoning? What effect has it on the duration of life? In what forms may lead poisoning manifest itself? What proportion of workers in lead are affected by it? What proportion of workers in mercury are affected by that metal ? To what disease -are mirror-makers especially prone ? What are some of the symptoms of mercurial intoxication? What peculiar effect has the metal upon female laborers and their children ? How may the bad effects of mercury be diminished ? What are the symptoms of" brass-founders' ague"? Is it common among the class indicated ? What S3'mptoms may indicate chronic zinc poisoning ? What are the symptoms of acute poisoning by aniline vapor ? What peculiarities characterize chronic aniline poisoning? Are these or others liable to be produced in those employed in the manufacture of aniline colors ? (247) 248 QUESTIONS TO CHAPTER IX. What class of diseases is especially apt to be caused by the con- tinued inhalation of dust? What is the most common affection among those who inhale coal-dust in large quantities? From what pulmonary disease are they exceptionally free? Is the expectation of life among this class of workmen high? What diseases seem to be especially favored by the inhalation of metallic dust? Which of these is the most frequent ? What is the effect of a mixture of metallic and mineral dust? What occupations have a high morbidity and mortality from phthisis? What from chronic pneumonia or other pulmonary affections ? To what peculiar affection are pearl-button-makers subject ? What workmen habitually inhale vegetable dust? What disturb- ances are due to the inhalation of tobucco-dust? What effect has it on fecundity, and why ? To what diseases are workers in cotton and flax subject, and from which one especially is the moi'tality high? What is the average dura- tion of life among paper-makers ? To what disease are rag- and wool- sorters liable ? From what affections do millers and workers in grain- elevators suffer? Why is the mortality from phthisis so high among brush-makers ? What substances are liable to cause disease b} T absorption or local action? What are some of the symptoms common to those working with arsenic ? What two classes of effects are observed among those exposed to phosphorus vapors? To what is each class due? What may be used as a preventive and antidote to such cases of phosphorus poisoning? AVhat malady is associated with the manufacture of qui- nine ? What other substances ma}' produce eczema or ulceration in their preparation or manufacture? What diseases are favored by continued exposure to high tempera- tures ? In what occupations are such disturbances accordingly prevalent ? What class of laborers are subject to sudden changes or to extremes of temperature? What are some of the maladies that may be, in part, traced to such causes? What are the effects of compressed air upon laborers in it, and when are they manifested ? What diseases or disturbances may be due to the excessive use of certain organs ? Is there any evidence that excessive mental activit}- leads to mental disease? What is a factor in the production of the latter? Why is the mortality-rate so high among those who follow sedentary or in-door occupations ? What disturbances are most common to these pursuits ? In what occupations are the laborers especially liable to mechanical violence ? Is the average duration of life of such work- men low or high ? CHAPTER X. MILITARY AND CAMP HYGIENE. ' i* THE subjects embraced in this chapter can be most con- veniently arranged under the following heads : I. The Soldier and his Training. IV. The Dwelling of the Soldier. II. The Food of the Soldier. V. Camp Diseases. III. The Clothing of the Soldier. VI. Civilian Carnps. I. THE SOLDIER AND HIS TRAINING. The relations existing among different nations at the present time require that a standing army of greater or less number be maintained by each for the common safety. This being the case, it needs no argument to prove that such an army should be composed of the best material available in order that it may be depended upon for defense or offense when necessity demands that it should be called into active service. Hammond says with truth 1 that " a weak, malformed, or sickly soldier is not only useless but a positive incumbrance " to an army. It is of the first importance, therefore, to exclude from the military service, by a rigorous physical examination, all individuals whose physical condition is defective, who are either suffering from or predisposed to disease. The foremost authorities on military hygiene are agreed that no recruit should be enlisted for actual service before the 20th year. In the English army the lowest age at present is 19 years ; in Germany, 20 years ; in France, 20 years for actual service (recrues), 18 years for enlistment (engages); and in the United States, 21 years. The limit of age upward in the latter army is 45 years, except in cases of re-enlistments. The height of recruits must be at least 165 centimetres; minimum chest 1 Hygiene, p. 19. Philadelphia, 1863. (249) 250 TEXT-BOOK OF HYGIENE. measurement 75 centimetres, with at least 5 centimetres' expan- sion ; and weight from 54 to 81 kilogrammes. In the cavalry service the maximum weight is 75 kilogrammes. Every recruit must be vaccinated before enlistment. The physical examination of recruits before enlistment must be made by a medical officer, whose decision, in the United States army, is definitive. In the German army the decision of the medical officer is not final, but subject to revision by the recruiting officer, who may, if he sees fit, overrule the medical officer's opinion and enlist a man who has been decided to be unqualified for the military service. In this and various other respects, such as pay, rank, and effective power, the Medical Staff of the United States Army has many advantages over that of most foreign armies. II. THE FOOD OF THE SOLDIER. The army ration of the United States, which is given below, was fixed by regulations before the more-recent researches of Professor Voit on nutrition were completed. The ultimate com- position, which yields 142 grammes proteids, 116 grammes fats, and 435 grammes carbohydrates, shows an excess of fats and deficiency of carbohydrates. Table XXI shows the daily allow- ance for each soldier : TABLE XXI. 342 grammes pork or bacon, or 567 " fresh beef. 454 " hard bread, or 566 " flour. 68 beans or peas, or 45 rice or hominy. 45 " green coffee. 17 " salt. 68 " sugar. To this is also added vinegar, pepper, and tea in place of coffee. Although the regular food-allowance in the United States army is liberal, and is largely in excess of the needs of the soldier THE CLOTHING OF THE SOLDIER. 251 in garrison, medical officers generally agree that in active service it is insufficient in quantity and not sufficiently varied. The money value of each of the above articles in the ration is fixed by the government, and may be drawn instead of certain of the articles, and other articles of food purchased and thus the dietary varied. The money so drawn constitutes what is known as the " company fund." In the hands of a judicious commanding officer, the company fund can be made a source of great benefit and comfort to the men, but that it is at times mismanaged or misapplied is well known to army sur- geons. Aside from the insufficient quantity and variety of food furnished to soldiers, the cooking, especially in temporary camps, is often defective and causes digestive derangements and con- sequent innutrition. A good cook should be attached to every company. in. THE CLOTHING OF THE SOLDIER. The clothing of the United States soldier is tolerably well adapted to its uses. It is generally well made, and of good, serviceable material. The only exception that can be made with reason is that the foot-gear is not made to individual measure, and hence peculiarities of shape of the feet cannot be taken account of. For this reason painful affections of the feet, due to ill-fitting boots or shoes, are of frequent occurrence. When on a march, the soldier carries his extra clothing packed in a knapsack and strapped upon the back. His blankets and ' great-coat are rolled into a cylinder and strapped upon the knapsack. The weight each soldier has thus to carry, in addition to his arms and ammunition, amounts to considerable. There is reason to believe that the pressure produced by the straps of a heavy knapsack may cause not only discomfort but actual disease. It is believed by many officers that the knapsack could be abolished with advantage, and the extra clothing rolled up in the blanket, or a water-proof sheet, and slung over the left shoulder. 252 TEXT-BOOK OF HYGIENE. IV. THE DWELLING OF THE SOLDIER. Soldiers are generally housed either in barracks, huts, or tents. The former are usually the habitation of the soldiers in garrisons or permanent camps, while huts or tents are used for the purpose of sheltering the occupants of temporary camps. Barracks. A military barrack is a one-storied building constructed of stone, wood, or iron, or a combination of these materials. The general plan of the barrack comprises a large room for the beds of the soldiers, one or more smaller rooms for the non-commissioned officers of the company or squad, and a wash-room. The sleeping-room of the soldier is also his living- or day- room. It is evident, therefore, that sufficient air-space and good ventilation must be provided if the soldier's health is to be maintained. In England, 17 cubic metres are recommended for the initial air-space. In the new barracks constructed in France according to the plans of M. Toilet, 22 cubic metres are allowed to each occupant. The special points of distinction of the system of Toilet, of which Schuster says that "to it belongs the future of barrack construction," are : The frame of the building is of light-iron ribs ; the interspaces are walled up with bricks or stone ; the roof is slate ; the ceiling is arched, and all corners are rounded to prevent lodgment of dust. Ventilation is provided by openings in the walls at the edge of the roof for the entrance of fresh air, and by ridge ventilators. In France, barracks have been built according to Toilet's system at Bourges, Cosne, Macon, and Autun. Although occu- pied but a short time, it appears that the health of the soldiers remains better in them than in the barracks constructed on the old style. The system would seem also especially to lend itself to the construction of hospitals. The wash- and bath- rooms of the barracks should be so arranged as to encourage the soldier to cleanliness. Where the only lavatory in a barrack is, as the author has seen it, an open porch, men are not likely to THE DWELLING OF THE SOLDIER. 253 spend much time in cold weather in washing their faces and hands, to say nothing of the rest of their bodies. The kitchen and dining-room should be detached from the building serving as quarters ; otherwise the odors of the cooking will pervade the building. The sinks or latrines should be placed at some distance from the quarters and kitchen, and out of the line of prevailing winds. The writer has personal knowledge of a permanent military post within a few miles of the city of Washington, where, only a few years ago (and, for aught known to the contrary, at the present day), " the rear," or place of depositing excrement, was about 70 metres distant from the kitchen and men's quarters, and directly in line with the prevailing winds ! Before erecting any buildings it is, of course, necessary to endeavor to secure a clean and dry subsoil. Attention is called to the principles underlying the construction of dwellings, Chap. VI. Tents and Huts. The tents used in the army are the hos- pital-tent, the officers' wall- tent, the A -tent, and the shelter- tent, which is a modification of the last. The conical, or Sibley tent, which was frequently seen in camps in the early part of the war between the States, has gone out of use. Soldiers give the preference to the shelter tent, which is light, each man's piece weighing only 1.18 kilogrammes. Two pieces being joined together by buttons and button-holes, and thrown over a ridge-pole supported upon uprights, and the four corners fast- ened to pegs driven into the ground, form a tent 1.20 metres high, 1.65 metres long, and having a spread at the base of between 1.8 and 2.1 metres. Such a tent will form a comfort- able shelter for two men, unless there should be strong winds or driving rains, when the ends could be closed by blankets, brush, or an extra piece of shelter-tent. The uprights and ridge are steadied by short guy-ropes, one of which is furnished with each piece of the tent. In winter, especially when camps of more or less perma- nence are formed, the soldiers usually build log huts. The 254 TEXT-BOOK OF HYGIENE. interstices between the logs are plastered up with mud or clay, and the roof is formed of canvas, generally several pieces of shelter tent joined together. The ground around the tent or hut should be trenched in order to carry off the rain-fall. Cleanliness within and around tents or huts is of the first importance, and should be enforced in all camps by the proper au- thority. Military authorities have long since learned that in the matter of cleanliness of body, clothing, or surroundings voluntary action on the part of the soldier cannot be relied upon. Frequent and thorough inspections will alone secure proper cleanliness. V. CAMP DISEASES. The soldier's profession has been aptly characterized by Ruskin as " the trade of being slain." In the late war between the States, the total deaths of the Federal army numbered 359,496, over 15 per cent, of the entire number of enlistments. Of this number, however, 224,586 (nearly two-thirds) died from disease, while the remaining 134,910 (a small fraction over one-third) were killed in battle or died from the effects of wounds. The colored troops especially suffered greatly from the effects of disease. Diarrhcea and Dysentery. The most fatal diseases of camp life, especially in time of war, are diarrhoea and dysentery. The statistics of the Federal army during the late war are given in the following table 1 : TABLE XXII. Total Deaths from Diarrhoea and Dysentery in the U. 8. Army, from May 1, 1861, to June 30, 1866. White Troops, from May 1, 1861. to June 30,1866. Colored Troops, from July 1, 1863, to June 30, 1866. Total Acute Diarrhoea .... Chronic Diarrhoea . . . Acute Dysentery .... Chronic Dysentery . . . Cases. 1,155,226 170,488 233.812 25,670 Deaths. 2,923 27,558 4,084 3,229 Cases. 113,801 12.098 35,259 2,781 Deaths 1,368 3.278 1,492 626 Cases. 1,269,027 182.586 259,071 28,451 Deaths 4.291 30,836 5.576 3,855 Total 1,585,196 37,794 153,939 6,764 1,739,135 44,558 1 Medical and Surgical History of the War, second medical volume, p. 2. CAMP DISEASES. 255 Owing to the fact that a considerable number of deaths were reported without assigning any cause, Dr. Woodward esti- mates the total number of deaths from- the above diseases at 57,265, or, in the proportion of one death from diarrhoea and dysentery to three and one-half deaths from all diseases. Among the prisoners of war held by the Confederate States in Anderson- ville prison, where tolerably complete records were kept, more than half the total deaths were from diarrhoea and dysentery, while the ratio of deaths to cases of the above two diseases was a fraction over 76 per cent. This frightful mortality from these two diseases, both in the prisons and among the armies in the field, is principally due to the insanitary conditions surrounding the soldiers. Where the demands of hygiene were especially ignored ; where the food was bad in quality, or badly cooked ; the water impure ; the soil polluted by excreta and other filth ; where the men were exposed to stress of weather or to a paludal atmosphere; under these conditions, the above diseases of the intestines prevailed in their greatest extent and most fatal degree. Malarial Fevers. The diseases due to the paludal poison are exceedingly frequent among soldiers encamped in malarial sections. During the Civil War a very pernicious form of malarial fever received the designation of the locality in which it prevailed, and passed into the literature under the name of " Chickahominy fever." While malarial diseases were largely represented in the morbility reports during the war, the most serious results of the influence of the malarial poison were manifested in its effects upon patients sick with other diseases. Thus, typhoid fever, dysentery, or pneumonia, in a patient saturated with malaria, was very much more serious than where this complication was absent. In the malarial regions in the interior of the country, the Mississippi Valley, and the southern portion of the Western Territories, malarial fevers are among the most prevalent camp diseases. Greater attention in locating camps, and care devoted to draining the subsoil and maintaining a low level of the ground- 256 TEXT-BOOK OF HYGIENE. water, would doubtless result in improvement in the sickness- rate from this cause in the army. Typhoid Fever. Typhoid fever is prevalent in camps and garrisons. As it may be propagated through the medium of infected discharges of typhoid patients, it will readily be perceived that neglect of the precaution of promptly disinfecting such dis- charges will almost inevitably result in spreading the disease, either by direct inhalation of effluvia from the patient or excreta, of pollution of the drinking-water, or by contamination of the soil, and subsequently of the atmosphere, by the intestinal dis- charges of the patient. Phthisis. Especially among troops in barracks phthisis is a very fatal disease. Formerly the mortality from it was very heavy. Recent improvements in the hygiene of military posts and greater care in selecting recruits have very greatly diminished the death-rate from phthisis among soldiers. Acute pulmonary affections, such as bronchitis, pleurisy, and pneumonia, are com- paratively frequent in camps, being due to exposure. Typhus Fever and Scurvy. These two diseases are at the present day comparatively rare as camp diseases. They break out, however, on every occasion when the laws of hygiene are violated by permitting overcrowding, overwork, and underfeeding. This is almost certain to occur during war, and hence either fully-developed scurvy or a scorbutic taint are almost constant accompaniments of an army in the field. Among the allied armies in the Crimea, and in the Federal army during the war, scurvy and typhus fever claimed a considerable share in the mortality. Purulent Conjunctivitis. This affection of the eyes is fre- quent among soldiers. It has even been supposed to be peculiar to soldier life, and has hence been termed " military ophthalmia." It is contagious, and is probably most often spread b'y the use of basins and towels in common. It is not merely annoying, but is a very grave affection, often causing perforation of the cornea and destruction of vision. The military surgeon should be on the lookout for it, and promptly isolate those infected. CAMP DISEASES. 257 Venereal Diseases. The contagious diseases of the sexual organs are a veritable scourge of the soldier's life. The history of these diseases is intimately interwoven with the history of armies, camps, and wars. The first wide-spread appearance of syphilis in the fifteenth century is coincident with the siege of Naples by the French army under Charles VIII. 1 It has since that time been a constant companion of the soldier in peace or war, and in all seasons and countries. Some progress toward its restriction has, however, been made in recent years in certain localities, but there is still wide room for improvement. In 1867 the venereal diseases reported in the Prussian army were 53.9 per 1000 of mean strength. In 1882 this number had been reduced to 41 per 1000, in 1883 to 36.4, and in 1884 to 32.8 per 1000. In the Austrian army there were 81 pei 1000 in 1870, diminishing to 73.5 per 1000 in 1884. In the British army the ravages of the venereal diseases were so terrible that legal measures for their restriction by subjecting prostitutes to inspection were taken. In 1859 the proportion of venereal disease among the home troops was 400 per 1000. In 1864 and 1866 the passage and enforcement of the "Contagious Dis- eases Act " caused a marked diminution of these diseases. This reduction is particularly noticeable in syphilis. The following table gives a comparative view of the number of cases of syphilis per 1000 in the naval service at ports under the acts, and at ports where the acts were not enforced: TABLE XXIII. Ports Under the Acts. Ports Not Under the Acts. 1860-1863 (no restriction), 75.02 per 1000 70.50 per 1000 1864-1865 (acts enforced), 79.12 " " 100.00 " " 1866-1870 (acts extended), 47.19 " " 84.74 " " 1871-1880,. . . . 40.64 " " 99.35 " " In the French army the proportion of venereal diseases was 53 per 1000 from 1862 to 1866. In 1867 the proportion in- creased to 106 per 1000. This increase was attributed to the 1 See article on Syphilis, Chapter XIX. 17 258 TEXT-BOOK OF HYGIENE. infection during the Mexican campaign. In 1879 the propor- tion had again diminished to 65.9 per 1000. In the United States Army the venereal diseases numbered 63 per 1000 among the white and 81 per 1000 among the colored troops in 1884. A chart drawn by Major Charles Smart, surgeon United States army, 1 shows in an interesting manner how opportunity for infection influences the increase of venereal disease. At the breaking out of the war, when large numbers of men enlisted, the record shows a rapid increase of venereal. When the armies were in the field, and opportunities for the pursuit of Venus were few, the proportion of venereal decreased. At the expiration of the first triennial period of enlistment, the soldier with his final pay and thirty days' fur- lough crowded the cities, and entered on a period of dissipation which usually sent him back to the recruiting officer with empty pockets and an attack of gonorrhoea or syphilis. At this time the records show a large number of cases, which gradually diminished until the end of the war, when the opportunities for infection preliminary to the final muster-out crowded the hospitals once more with venereal cases. The experience with the Contagious Diseases Act in Eng- land points out the true way to limit or entirely extirpate this disease among the military and naval forces. An inspection at regular intervals not only of public prostitutes, but also of the soldiers themselves, and segregation of the infected in hospitals until the infective period is past, will do more to limit the spread of venereal disease than all other preventive measures, public or private, put together. VI. CIVILIAN CAMPS. The camps of civil life, whether established for the purpose of furnishing a refuge to the inhabitants of cities invaded by epidemic diseases, as yellow fever or cholera, or whether for religious purposes (camp-meetings), or for recreation (hunting Medical and Surgical Hiscory of the War, third medical volume. CIVILIAN CAMPS. 259 and fishing camps, etc.), should be organized and managed on the same principles as the military camp. The site should be selected with judgment a clean, dry soil, and abundance of wood and water being requisite for a healthy camp. A superintendent or officer of the day should be appointed, whose duty it is to carefully inspect the camp daily, and compel the prompt removal of all filth and offal from the immediate vicinity. Cleanliness of person, clothing, and household is as important while " roughing it " in camp as at home. Singularly, this is very often forgotten by very intelligent people. The advantage of a well-administered refugee camp in case of yellow-fever epidemics has been clearly shown by the brilliant success of the depopulation of Memphis during the epidemic of 1879 and of various Florida cities and towns in 1888. These experiments deserve imitation. [The following works on Military and Camp Hygiene should be studied in connection with this chapter : Smart, The Hygiene of Camps, in Buck's Hygiene and Public Health, vol. ii. Wolzendorff, Armee Krankheiten, in Realencyclopaedie d. ges. Heilk., Bd. I, p. 489. Schuster, Kasernen, in von Pettenkofer und Ziemssen's Handbuch der Hygiene, II Th., 2 Abth. Cameron: Camps, Depopulation of Memphis, Epidemics of 1878 and 1879. Public Health, vol. v, p. 152. Frolich, Militarmedicin. Medical and Surgical History of the War, especially the second and third medical volumes. Annual Reports of the Supervising Surgeon-General of the United States Marine Hospital Service, 1888-9.] QUESTIONS TO CHAPTER X. MILITARY AND CAMP HYGIENE. What subjects may be considered under this head ? Why should an army be composed of sound and healthy individuals ? Who should be excluded from an army or body of troops ? What is the lowest age at which recruits should be enlisted? What the highest age? What should be the minimum measurements of the recruit? Who should make the physical examination of the latter ? What can be said for the present army ration of the United States? In what is it excessive and in what deficient? In what other ways is it objectionable? What besides insufficient quantity and variety of food may cause digestive disturbances and innutrition in camp? What part of the United States soldier's clothing at present is most apt to cause physical discomfort? What change might be made to advantage in the manner of carrying the extra clothing ? How is it now carried ? What usually constitutes the dwelling of the soldier ? What is a military barrack, and what is its general plan ? What are the special points in favor of the Toilet system' of barrack construction? What is to be said about the location of barrack lavatories, kitchens, and dining- rooms, sinks, and latrines ? On what kind of soil should barracks be located ? What sort of tents are used in the army ? What are the advantages of the simple shelter tent ? What may take the place of tents in winter ? What is of the first importance in all camps, and what is necessary to secure this ? In actual war what relation do the deaths from disease bear to those from injuries received in battle ? What are the most fatal diseases of camp life? What are the causes leading to this fact ? What other class of diseases is especially apt to be frequent among soldiers? What effect has the malarial poison on those sick with other diseases ? What would lessen the prevalence of malarial fevers in camp-life? How may typhoid fever be propagated in camps and garrisons ? What respiratory diseases are common in camps, and to what are they due? What two diseases, formerly common in camp-life, are now rare? What affection of special sense is frequent among soldiers, and to what is this frequency to be attributed ? What contagious diseases are especially associated with the soldier? By what means mny their spread be restricted? For what purposes may civilian camps be instituted ? What prin- ciples should be followed in organizing and maintaining them ? What are prime requisites ? Who should be in charge of such a camp ? Of what advantage may such camps be in case of epidemics of contagious diseases ? (260) CHAPTER XI. MARINE HYGIENE. THE melancholy accounts of the mortality from scurvy, dysentery, and typhus fever, which were formerly a part of the history of so many naval and passenger vessels, are happily now only records of the past. Occasionally, however, careless- ness of the authorities, or of those responsible for the safety of people who " go down to the sea in ships," results in an out- break of one or other of these diseases even at the present day. Thus, for the fiscal year ending June 30, 1882, 71 cases of scurvy and purpura were reported by the medical officers of the Marine Hospital Service. It appears that only in one instance (where 6 cases of scurvy had occurred on one vessel) was any investigation ordered. A most superficial investigation showed that the law relating to the issue of lime-juice had been violated by the master of the vessel. No prosecution resulted. Such facts indicate that laxness in the enforcement of the regu- lations expressly made to prevent this fatal disease may be again followed by outbreaks of greater or less gravity. I. THE SAILOR AND HIS HABITS. Although the sailor of the present day, especially in the naval service, is morally and intellectually far in advance of the " Jack Tar " of former days, his life, both afloat and on shore, leaves much to be desired on the score of temperance, chastity, and purity of thought and speech. The life of a sailor in the United States navy, thirty-eight years ago, is thus graphically described by Medical Director Albert L. Gihon 1 : " She was manned by a motley crew, of whom Americans were a minority, 1 Thirty Years of Sanitary Progress in the Navy : Annual Address by the President to the Naval Medical Society, Washington, 1884. (261) 262 * TEXT-BOOK OF HYGIENE. and Englishmen, Irishmen, Northmen, and ' Dagos ' constituted the far greater part. Some had just returned from another cruise, having squandered or heen robbed of their three years' pay by the 'landsharks', who cajoled them, only half sober, to the ren- dezvous, to be reshipped, and thence to be herded, uncared for, on the receiving-ship, still popularly termed the ' guardo,' until drafted on board the first sea-going vessel. All of them were in debt, most of them insufficiently clad, and unable to properly outfit themselves. The wretched herd, who were thus gathered from the purlieus of Water Street, and North Street, and South Street, who at night were kenneled worse than dogs, by day fed like them, crouching on their haunches around greasy mess-cloths, cutting with jack-knives or pulling to pieces with grimy fingers the chunks of ' salt horse' and 'duff' which made their daily fare, and which, later in the cruise, were both spoiled and scanty, did not constitute an elevating subject for contemplation. " Stint of good food," continues Dr. Gihon, "was, however, not the chief of the old-time ' shell-back's ' ocean trials. Fed like a brute, housed worse than one, however faithfully his labors were performed, there was for him only a long, dreary season of imprisonment. For him there was no glad holiday on shore, when the land broke the monotony of the waste of waters. The officers might rush pell-mell out of the ship, but Jack could only strain his longing eyes upon the green fields or busy sea- ports. Notwithstanding the hardships of the voyage, the wretched food, and the outbreaks of disease, the crew were con- fined eight months on board ship, before ' general liberty ' was given, and then men and boys were sent on shore for forty-eight hours to indulge in a mad revel, and to return crazed by rum, battered, and bruised. The poor wretch, first made ravenously hungry for dissipation by his enforced confinement, was then expected to be temperate in the feast of indulgence offered him, and punished with vindictiveness if he sought to gorge himself with the poor semblance of pleasure. The 'cat' had been THE SAILOR AND HIS HABITS. 263 abolished, but half a dozen boys strung upon the poop 'bucked and gagged ' ; half a dozen men triced up by their thumbs in the rigging ; each of the upright coffin-like ' sweat-boxes' with its semi-asphyxiated inmate ; the ' brig ' with its bruised and bloated crew in irons ; the main-hold with its contingent under hatches ; the sick-list swollen out of all proportions by in- ebriates, injured men, and venereal cases ; these were the fruits of the * general liberty,' which, within my professional life, represented the sum of sanitary interest in the man before the mast." Under such circumstances little could be hoped for in the way of personal advancement of the crew. The labors, how- ever, of the writer just quoted, and others, among whom may be mentioned Wilson and Turner, of the navy, and Wood worth, Hebersmith, and Wyman, of the Marine Hospital Service, have drawn prominent attention to the unsanitary conditions of the sailor's life, and legal enactments have done much to elevate him to his proper rank as a human being, entitled to be treated with humanity, at least. The seaman in the navy is now well clad, and receives an abundance of food, of good quality, usually well cooked and decently served. " Latrines and bath- and wash- rooms under the top-gallant forecastle ; mess-tables and benches ; mess- lockers and clothes-lockers ; a place where, and opportunities when, men can read and write ; and frequent daily liberty to go on shore, if not already common to every vessel, are yet now so generally the concomitants of the well-officered and well-dis- ciplined and efficient ship, that ere long their absence will be accounted a fault." * A medical corps, selected after the most rigorous examination known to the profession, and provided with every aid and appliance of medical science, cares for the enlisted sailor and marine when ill or injured, as tenderly as for the commissioned officer. The sailor in the merchant service, however, is still at the 1 Thirty Years of Sanitary Progress in the Navy, Gihon. 264 TEXT-BOOK OF HYGIENE. mercy of inhuman masters, who exact excessive service in return for insufficient food, scanty clothing, miserable lodging, abuse, ill-treatment, and neglect when sick or disabled. II. THE PASSENGER. During the ten years from 1870 to 1879, inclusive, passen- ger vessels carried 1,561,126 passengers from foreign ports en route to New York City. The mean duration of each voyage was 13.5 days. Out of the above number of passengers 2518 died on the voyage, a death-rate of 1.61 per 1000 for the voyage and 43.5 per 1000 per annum. These figures accentuate the importance of sanitary improvement in passenger vessels. The causes of this excessive mortality among emigrants for it is almost exclusively among the passengers in the steerage, or " between decks," that the deaths occur are overcrowding, im- proper feeding, defective ventilation, filthy personal habits, and inefficient medical attention when sick. Although overcrowd- ing is prohibited by statute, yet in every emigrant vessel that arrived in New York during the first nine months of 1880 the number of passengers was in excess of the number allowed by law. 1 The shorter voyages and better sanitary conditions ob- tainable since steamships, especially those built of iron, have come into general use for the carriage of passengers, have very much reduced the mortality on ocean voyages ; but, as just shown, the death-rate is still excessively high, and many more im- provements in the hygiene of emigrant vessels and of passengers are desirable. III. THE SHIP AS A HABITATION. As a habitation for the sailor and passenger the ship de- mands the attention of the sanitarian. The principal points in which he is interested are the construction and ventilation of sleeping-apartments, and the means of keeping the entire ship clean and free of water and impure air. The keel is the foundation of the ship. Branching out 1 Hygiene in Emigrant Ships, Turner, Public Health, vol. vi, p. 24. THE SHIP AS A HABITATION. 265 transversely from it are curved timbers, the ribs, which, with the keel, constitute the ship's frame. The ribs are covered exter- nally and internally with planking, and the spaces between the two coverings are the frame-spaces, which are usually partly filled with filthy water, decomposing organic matter, and foul air. The water collects in the bottom of the vessel, the bilge, 1 whence it is pumped out of the vessel. If the pumping is neglected the bilge-water becomes very offensive, and may cause disease in persons exposed to exhalations from it. The frame- spaces are rarely ventilated, and hence are frequent sources of pollution of air on board vessels. The sleeping-apartment of the crew of a merchant vessel is in the forecastle, usually a small, dark, damp, filthy, un ven- tilated space in the bow of the vessel, where they are kenneled like brutes. On naval vessels the crews sleep on the berth- deck, which, in the rarest instances, is properly lighted and ventilated. The berth-deck is usually below the water-line. In nearly all and even the best class of vessels in the United States navy the air-allowance for each man is less than 3 cubic metres, rarely reaches 4, is oftener from 2 to 2^, and is some- times as low as 1 cubic metre. The men swing by night in hammocks suspended from the beams overhead, and removed when not in use, carried on deck, and stored in lockers, called "hammock-nettings," on the ship's sides. That a ship should, above all, be seaworthy would seem to require no argument. It is self-evident that a leaky or rotten ship is at all times a highly dangerous habitation, yet crews and passengers are almost daily exposed to the perils of shipwreck in unseaworthy vessels, especially in the mercantile marine. 2 "Dampness, dirt, foul air, and darkness," according to Gihon, " are the direst enemies with which the sailor has to battle when afloat." 3 The first requisite for a healthy ship is 1 Hence called "bilge- water." 2 The Safety of Ships and Those who Travel in Them, Woodworth, Public Health, vol. iii, p. 79 et seq. * Naval Hygiene, 3d ed., p. 28. 266 TEXT-BOOK OF HYGIENE. dryness. "A damp ship is an unhealthy ship," says Fonssa- grives, the greatest authority on naval hygiene. From official reports it appears that the relative humidity of the berth-deck of vessels in the United States navy is nearly always above 80 per cent., very often rising to 90 and 95 per cent. 1 From the same source it is learned that the class of respiratory diseases furnished, with one exception, the largest amount of sickness in the navy during the year 1880. It is the concurrent testimony of all authorities in marine hygiene that the vicious custom of daily drenching the decks with water, under the plea of cleanli- ness, is mainly responsible for this excessive moisture and its results. The battle of naval hygiene was long fought on this contested field of wet decks, until the fact became so patent that wet ships were always unhealthy ones. It is, therefore, one of the most important aims of marine hygiene to curtail this practice. Gihon recommends that the decks be painted and then coated with shellac, occasionally renewed, to make them non- absorbent, and to wet them as rarely as possible, consistent with cleanliness, the smooth surface of the shellacked deck being quickly swabbed over with hot water and thoroughly dried. The ship should be clean and well ventilated. Efforts to keep a ship clean should not be expended upon the decks only; the occupied apartments below the hatches, the bilges and frame- spaces should all receive especial attention from the sanitary inspector. It is quite frequently necessary to remove the flooring of the vessels in order to expose the accumulations of filth, which often make an infected ship synonymous with a dirty ship. An unobstructed passage, to which ready access can be had through removable covers, should extend under the flooring from one end of the vessel to the other. To disinfect a dirty ship, steam forced into the hold under pressure, before and after the filth has been cleaned out, gives the most satisfactory results. 1 Report of Surgeon-General of the Navy, Washington, 1880. THE SHIP AS A HABITATION. 267 Chlorine and fumes of sulphur burned in the presence of watery vapor are next in efficiency. 1 Solutions of sulphate of iron or chloride of zinc may be poured into the bilges to prevent decomposition. It has been estimated 2 that a minimum of 15 cubic metres of air-space, with facilities for thorough ventilation, should be allowed to each person on board ship. It is safe to say that no vessel that floats gives to her passengers or crew the advantages of such conditions. Ventilation of the holds and bilges, and of the spaces between the frames or ribs, " intercostal ventilation," as Turner calls it, is especially necessary. Any system of ven- tilation that does not contemplate the removal of the foul bilge-air is unworthy of consideration by the sanitarian. The ventilating apparatus which has been introduced on board the modern vessels of the United States navy consists essentially of longitudinal mains extending^through the entire length of the ship, connecting with powerful fan-blowers usually located on the berth-deck nearly amidships. In large vessels four blowers are fitted, each being connected with an independent system of pipes and all fitted with reversible valves, so that they may be used either for exhausting foul air or supplying fresh, and also fitted so that the fan systems can be used in combination, thus simultaneously exhausting foul air from and supplying fresh air to any compartment in the vessel. These blowers are driven at about four hundred revolutions per minute and are of sufficient power to maintain a vacuum of a half-inch below the atmosphere throughout the entire systems of pipes. Small metal pipes connect these longitudinal mains with every state- room, store-room, pantry, and other inclosed apartment on the berth-deck, orlop, and holds. All the openings in these pipes are bell-mouthed and fitted with wire gauze and registers, with a clear opening equal to twice the area of the pipe. Additional ventilating pipes are led from the bilges, wherever necessary, up 1 Report of Committee on Disinfectants, American Public Health Association. 3 "Hygiene of Emigrant Ships," Public Health, vol. vi, p. 26. 268 TEXT-BOOK OP HYGIENE. the sides of the vessel, terminating in brass louvres inside the bulwarks, these being also fitted with additional louvres between decks, especial care being taken to prevent the foul air from the bilges thereby reaching the living-spaces. Fresh air finds its way below through the wind-sails, venti- lating-shafts, hatchways, and air-ports, entering the apartments by way of doors, crevices, and other natural apertures. The absolutely essential condition of this system of ventilation is that the blowers shall revolve, but, unfortunately, sanitary interests are too often sacrificed on the pretext that economy of fuel will not permit the operation of the fan. 1 All parts of the vessel used as habitations or sleeping- apartments should receive sufficient sunlight. At present, very few vessels have the quarters of the crew so disposed as to admit any sunshine at all. In the fire-rooms of steam-ships, especially on that class of naval vessels termed monitors, the temperature often rises so high as would seem to render continued existence in it impos- sible. Gihou states that the average temperature in the fire- room of the monitor Dictator was 145 F. (63 C.), while Turner states that in another vessel the average fire-room tem- perature was 167 F. (75 C.). 2 The firemen and coal-heavers (stokers) frequently suffer from heat-stroke, and, in a very large proportion of cases, from heart disease. Lavatories and bathing facilities should be furnished on vessels for passengers and crew, and both should be compelled to keep their bodies and clothing clean. A more liberal supply of water for drinking, a more frequent issue of fresh meat and vegetables, and better cooking are the sanitary considerations to-day in the subsistence of the sailor. The American naval ration is superior in variety, nutrient value, and palatableness- to that of any foreign service; but skilled cooks are still a de- sideratum on board men-of-war, and medical officers have Ions: O been insisting that schools for their instruction should be estab- 1 Hygiene (Naval), Hnnd-lionk of the Medical Sciences, Gihon. * Buck's Hygiene and Public Health, vol. ii, p. 190. THE SHIP AS A HABITATION. 269 lished at recruiting stations. The composition and distribution of the rations are given in the following table : TABLE XXIV. ALLOWANCE FOB GENERAL DAILY USE. (Either one of the following.) Rations Established by Law. Specified by Law. Substitutes Authorized by Law. Ration No. 1 . Ration No. 2 Ration No. 3 . Ration No. 4 . 1 lb. salt pork .... pint beans or peas . 1 lb. salt beef .... lb. flour 2 oz. dried fruit . lb. preserved meat . | lb. rice 2 oz. butter . . 1 oz. desiccated mixed vegetables 1 lb. preserved meat . . 2 oz. butter ...... 6 oz. desiccated tomatoes 1 li lb. fresh meat ; or, 1 lb. preserved meat. Vegetables of equal value ; or, lb. rice. 1^ lb. fresh meat ; or, A lb. preserved meat. Vegetables of equal value. No substitute. A pint beans or peas. No substitute. 6 oz. canned vegetables. No substitute. No substitute. 6 oz. canned tomatoes. DAILY ALLOWANCE. Specified by Law. Substitutes Authorized by Law. 1 lb. soft bread. 1 lb. flour. lb. rice. 2 oz. coffee. 2 oz. cocoa. For coffee and sugar, extract of coffee combined with milk and sugar may be substituted by the Secretary of the Navy, if not more expensive. ^ oz. tea < 4 oz. sugar WEEKLY ALLOWANCE. Specified by Law. Substitutes Authorized by Law. pint pickles 2 . pint molasses pint vinegar . None. None. None. 1 These articles being out of the market, and, not procurable, the nearest possible sub- stitutes arc Riven. a One-half pint pickles is considered equal to one-half pound, and is issued as such. 270 TEXT-BOOK OF HYGIENE. The substitutes authorized by law permit nine variations of ration No. 1, six of ration No. 2, three of ration No. 3, and two of ration No. 4. The quantity of fresh vegetables authorized is to be equal in value to any or all of the articles usually issued with the salted meats, for which they may be substituted, the allowance fixed for issue being one and one-fourth pounds per ration. Dried fruit may be either dried apples, peaches, raisins, currants, prunes, figs, dates, or any other dried fruit. Preserved meat comprises roast or compressed beef, Chi- cago corned beef, fresh mutton, or any other canned preserved meat, ham, brawn, bacon, sausage, salt fish, and any other salted or smoked preserved meat. In addition to these, the daily allowance of fourteen ounces TABLE XXV. UNITED STATES NAVY SEA- OK SALT- RATION. ONE WEEK'S ISSUE. ARTICLES. ALLOWANCE. NUTRIENTS IK GRAMMES. Mineral Matters. 33* S&S a Isl faH Lb. Oz. Protein. Fats. Carbo- hydrates. Salt pork * . . 2 1 4 1 2 8 8 2 4 6 12 8 6 8 1.50 194.14 115.78 231 33 13.77 16.78 60.55 10478 49.89 433.41 2.72 1.70 52.05 0.78 69.40 2.04 0.90 3&T 9.07 4.98 36.11 144.58 66.33 180.07 127.91 270.53 339.74 2039.27 70.30 0.85 776.33 165.79 163.57 82.0 32.16 0.90 6.57 14.06 2.26 24.23 5.10 Salt beef 1 . . . Preserved meats 2 . . Canned vegetables . Rice 3 Beans 1 1 6 Flour 3 Biscuit Dried fruit Butter Sugar 1 Molasses Cocoa Coffee Tea Vinegar and pickles. 1 Total 22 1.50 1224.85 323.76 4037.12 330.85 Daily average . . 8 0.35 174.98 4625 576.71 47.26 3515 1 Eighteen per cent, waste. 9 Corned beef, roast beef, and sausage meat. Substitutes : Ham, brawn, bacon, smoked and salt fish. 1 Or cornmeal, hominy, oatmeal. DISEASES ON SHIPBOARD. 271 TABLE XXVI. UNITED STATES NAVY FRESH RATION. AVERAGE DAILY ISSUE. ARTICLES. ALLOWANCE. NUTRIENTS IN GRAMMES. Mineral Matters. Potential Energy in Calories. Lb. Oz. Protein. Fats. Carbo- hydrates. Fresh meats * ... Fresh vegetables 2 . Fresh bread .... Flour 1 1 1 4.0 4.0 228 0.85 4.0 87.68 10.71 37.71 7.12 0.08 7448 0.43 7.71 0.72 21.99 74.19 2o5.37 48.53 110.90 23.80 10.04 4.35 4.08 3.98 0.32 0.22 Butter Sugar Molasses Dried fruit . . . 1.14 0.57 0.85 1.14 0.18 2.28 0.39 Cocoa Coffee Tea Pickles and vinegar. Total. . . . 4 5.29 143.69 105.33 522.83 12.95 3715 THE DAILY AVERAGE UNITED STATES NAVAL RATION. The mean of all food-supplies r Protein 157.34 Fats 75.59 Carbohydrates 549.77 Mineral matters 30. 10 Potential energy in calories . . . 3615 . Potential energy in foot tons . . . 5531 of biscuit can be varied by tbe substitution of one pound of soft bread, or one pound of flour (which may be either wheat, rye, cornmeal, oatmeal, or hominy), or one-half pound of rice. 3 Surgeon Charles A. Siegfried, of the United States navy, has tabulated the American naval ration according to its nutrient value. 4 (See Tables XXV and XXVI.) IV. DISEASES ON SHIPBOARD. The diseases most liable to attack persons on shipboard are: Diseases of the respiratory organs, rheumatism, .malarial diseases, digestive disorders, scurvy, typhus fever, and skin diseases ; and, where the infection has been conveyed to the 1 Twenty per cent, waste. Calculated from total fore and hind quarters. 3 Eighteen per cent, waste. Potatoes, onions, cabbage, etc., mixed. * U. S. Navy Ration Regulations, 1884. 4 Journal of American Medical A-ssociation, December 31, 1892. 212 TEXT-BOOK OF HYGIENE. vessel by other persons or by fomites, yellow fever, cholera, small-pox, and venereal diseases. It is interesting to note, in a recent report of the Surgeon-General of the Navy, that, among a total of 8550 admissions of sick and disabled officers and men of the navy and marine service, nearly 90 per cent, were included in the following classes, to wit : Casualties, 1911 Affections of the respiratory tract, . . . 1149 Venereal diseases, 1071 Malarial and other fevers, 888 Diseases of the integument, .... 888 Rheumatism, ....... 521 Affections of the nervous system, . . . 489 Diarrhceal maladies, 483 The remaining 1144 were distributed over a wide range of titles, of which many, as adynamia, cephalalgia, constipation, odontalgia, etc., have no special pathological significance. It is probable that only about one-fourth of the cases of disease occurring at sea are attributable to any of the circumstances of oceanic life, and these are almost entirely inflammatory affections of the air-passages and intestinal tract, neuroses, including nausea marina, and rheumatism. 1 Most of these affections can be prevented by proper meas- ures of hvgiene, as demanded bv the conditions described in this / o / chapter or by the enforcement of the following regulations : Inspection of crews and passengers should be made com- pirlsory before shipment. Persons suffering from contagious or infectious diseases should not be taken on board. 2 In order to make this provision effective, the history of the individual for two weeks prior to his application for shipment should be known to the inspecting officer. Passengers should possess bills of health from the local authorities at their homes, in order that 1 "The Therapy of Ocean Climate," Gihon, Transactions of American Climatological Association, 1889. 1 Gihon relates an instance where a man suffering from parotitis was transferred from the hospital of a, receiving-ship to a vessel going to sea. The disease was communicated to more than seventy of the crew of the latter vessel. DISEASES ON SHIPBOARD. 273 the presence or absence of such diseases as small-pox, yellow fever, cholera, or plague may be established by the inspector. Cholera has always been introduced into this country by immi- grants. Everybody admitted to the ship should be vaccinated. During several years past a number of epidemics of small-pox have been traced to foreign immigrants who had not been properly vaccinated. Sailors in the merchant service should, like those in the navy, be submitted to a close personal inspection, and those suffering from venereal diseases should be rejected. The usual history of the cases is that they soon . go on the sick-list, and thus become an incumbrance instead of an aid on the vessel. Statistics show that 1 man in every 7 or 8 in the naval service and 1 in every 4 of the crews of merchant vessels are affected with some form of venereal malady. 1 These inspections should not be restricted to examinations for venereal diseases, but indi- viduals incapacitated for the performance of a seaman's duties by any cause should be rejected. This precaution would un- questionably reduce the number of marine disasters directly traceable to deficiency in the working force on board vessels. In this country the services of the medical officers of the Marine- Hospital Service might be made available to carry out these inspections. All sailors are liable to be placed in positions where the prompt and accurate distinction of colors becomes necessary; hence all color-blind individuals should be rejected as seamen. The inability to distinguish colors has often been the cause of grave accidents at sea. Pilots can no longer obtain a license unless they satisfactorily pass an examination with reference to their ability to distinguish colors. The protection of the passenger on shipboard, as well as the safeguarding of a country against the introduction of exotic epidemic diseases, demands that the sanitary and medical service on board emigrant ships shall be the best attainable. 1 "The Prevention of Venereal Diseases," Gilion, Public Health, 1882. 18 274 TEXT-BOOK OF HYGIENE. At present there are still many short-comings. A recent report made to the American Public Health Association, by a com- mittee appointed for the purpose, gives an authoritative ex- pression of opinion upon these points. The committee advise : "1. As to the location and dimensions of the quarters for emigrant passengers, the number of berths in each, and the provisions for their ventilation and cleansing : " That the preferable location for such quarters is abaft the midship section of the vessel ; that single males' quarters shall be distinct from those occupied by women and children, and that, if any are forward the midship section, it shall be those for single men. " That there shall never be more than two decks (properly there should be only one) occupied by emigrant passengers' berths, with sixteen feet of superficial space for each adult on the upper berth-deck and twenty feet of such space on the lower berth-deck, with not more than two tiers of berths on each deck, the bottom of the lower tier being not less than eighteen inches above the deck, with not less than thirty inches between the two tiers and between the upper tier and the ceiling of the compartment, to allow the occupants of the berths to sit upright. "That no solid partitions or bulkheads shall be placed in any steerage compartment to obstruct light and air. "That the frame-work of the berths shall be of iron, easily removable, that the compartment may be completely emptied and thoroughly cleaned after each passage. " That a steam ventilating apparatus by aspiration shall be introduced into all emigrant vessels ; and " That all compartments occupied by passengers and crew shall be lighted by the incandescent electric light by night and by day. " 2. As to the location and dimensions of hospitals on board such vessels and the number of sick-berths for which, provision should be made : DISEASES ON SHIPBOARD. 275 " That the hospitals, or ' sick-bays,' on board emigrant pas- senger vessels shall be at the extreme after part of the upper deck, thoroughly lighted and ventilated, with eighteen feet of superficial space for every fifty passengers, and not less than four sick-berths or hospital cots for every hundred passengers. " 3. As to the number of medical officers proper for the maximum of emigrant passengers any vessel should be per- mitted to carry, being the maximum number able to be berthed with regard to health, cleanliness, and comfort: "That there should be one duly-qualified medical officer for every two hundred and fifty passengers. " 4. As to the professional records which the senior medical officer of every such vessel should be required to keep, and his responsibility to the health authorities of the port of arrival for the truthful and professionally-accurate statements of such records : " That the senior medical officer of every such vessel shall be required to keep (1) a list of sick, recording in a bound book, in the order of their admission, and on a single line, the name, sex, age, birthplace, date of admission to treatment, date of death or discharge from treatment, disease, and such remarks as may be necessary to enable the inspecting medical officer at the port of arrival to have a clear and complete understanding of the case ; (2) a medical journal, in which each medical officer, when there are more than one, shall record the medical history, including symptoms and treatment of every case, to be approved and signed by the senior medical officer at the close of the day's record ; and such list of sick and medical journal shall be submitted to the health authorities of the port of arrival, and the accuracy of the statements in such records shall be established by oath, and penalties for perjury shall be provided. " 5. As to the location and capacity of latrines for emigrant passengers : "That the latrines shallow troughs with a continuous flow of salt water shall be on the upper deck, under shelter, 276 TEXT-BOOK OF HYGIENE. with two water-closet seats for every fifty passengers, with a proportionate number for women and children, in a separate locality, near their own quarters, inaccessible to men. " 6. As to the number of attendants provided for such pas- sengers, and their duties as to policing and cleansing emigrants' quarters : " That there shall be not less than one berth-deck attendant for every fifty passengers, female attendants in the same propor- tion being exclusively assigned to the quarters for women and children. " That the berth-decks shall be thoroughly cleansed every morning by the attendants, never wetted in rainy or damp weather, when they shall be scraped, swept, and freshly sanded ; and in pleasant weather washed with hot water and quickly dried, the passengers being sent on deck during the operation. " That the berth-deck attendants shall be on duty night and day in rotation by regular sea watches, and the attendants on watch required to remove the dejecta of seasick passengers without delay. " That benches and mess-tables shall be provided, and the passengers' food be distributed by the berth-deck attendants, who shall take away all unused food and carry the dishes to the pantry. " 7. As to additional provisions for the personal health, cleanliness, and comfort of emigrant passengers: " That wash-rooms, under cover, with basins supplied with running water, shall be provided on the upper deck ; those for men to be separate from those intended for women and children. " That fresh water for drinking purposes shall be provided in each compartment ; and " That inexpensive mattresses, pillows, these to be service- able as life-preservers, and blankets shall be provided for emi- grant passengers, the mattresses to be destroyed after each passage, and the pillows and blankets to be steamed and washed before being ag.ain used." DISEASES ON SHIPBOARD. 277 [The following works contain more detailed information upon the subject treated in the foregoing chapter : Albert L. Gihon, Practical Suggestions in Naval Hygiene, 3d ed., Washington, 1873. T. J. Turner, Hygiene of the Naval and Merchant Marine. Buck's Hygiene and Public Health, vol. ii. Walter Wj'inan, Hygiene of Steam-boats on the Western Rivers. Report of Supervising Surgeon-General M. H. Service for 1882. Annual Reports of the Surgeon- General of the Navy for 18t9, 1880, and 1881. Various papers by J. M. Woodworth, Albert L. Gihon, T. J. Turner, Hebersmith, and A. N. Bell in Public Health, vols. i, iii, and vi. Hygiene, Naval, by Albert L. Gihon, M.D., in Reference Hand-book of Medical Sciences.] QUESTIONS TO CHAPTER XI. MARINE HYGIENE. What is meant by marine hygiene ? In what respects is the condi- tion of the sailor in the United States navy now better than formerly ? Is the merchant sailor as fortunate ? How does the death-rate on passenger vessels compare with that on shore ? What are some of the causes of the excessive mortality among steerage passengers ? In what ways can these causes be prevented ? What are the principal points about a ship in which the sanitarian is interested ? What tends to pollute the air of a ship ? What is meant by the bilge and bilge-water ? By the frame-spaces ? Where are the sleeping apartments usually of a merchant crew ? Of a naval crew ? What are the faults of each ? What are the sailor's greatest enemies when afloat? What is the first requisite for a health}' ship ? What is the relatiye humidity of the berth-deck in most United States naval vessels ? To what is this excessive humidity largely due ? How might this be avoided ? What class of diseases is especially preva- lent in the navy ? How else may the sanitary condition of a vessel be improved ? What is meant by a clean ship? How may a dirty ship be disinfected ? Where is ventilation especially necessary on a vessel ? What amount of air-space should be allowed each person on board ship ? Is this customarily provided for ? Describe the ventilating appa- ratus of vessels of the United States navy. Upon what does the efficacy of this depend, and in what respect is it faulty ? Do the sleeping-apart- ments of vessels receive sufficient sunlight ? To what maladies are the firemen and coal-heavers of steam-vessels subject? What other con- siderations affect the health of the sailor ? What are some of the diseases most liable to attack persons on ship- board ? What is the probable order of frequency ? What proportion are really attributable to the sea-life ? How can most of the affections be prevented ? What hygienic regulations should be enforced both be- fore and after embarkation. Why ? With what should each passenger be provided? What sailors should be rejected and not enlisted? What may happen if this course is not followed ? What officers might carry on the inspection in this country ? (278) CHAPTER XII. PRISON HYGIENE. ALTHOUGH the frightful mortality which formerly seemed a necessary accompaniment of the life of the convict has in the past half-century markedly diminished, the death-rate among prisoners is still very greatly in excess of that of persons of the same age in a state of liberty. The observations and labors of John Howard, the self- sacrificing philanthropist, in the latter half of the last century, and of Elizabeth Fry, in the first half of the present, directed the attention of legislators to the necessity of reform in the con- duct of prisons and the treatment of prisoners. As a conse- quence of the labors of these reformers, the principles of prison discipline have been more fully developed during the past forty years by students of social science everywhere, and certain propositions have been formulated, which govern, to a greater or less degree, legislation upon this subject. These propositions are, briefly, as follow : Prisoners must be properly classified according to the nature of their crime and the duration of imprisonment. The two sexes must be strictly separated, and no oppor- tunity given for intermingling while in the prison. Female prisoners should have female attendants exclusively. Male watchmen or other attendants should not be allowed in the female department of a prison. All prisoners must be kept employed at some manual labor, not necessarily for profit, but as an agency in the moral reforma- tion of the convict. Punishments for infractions of discipline must not be excessive. (279) 280 TEXT-BOOK OF HYGIENE. Efforts should be constantly made tending to the reclama- tion of criminals from their life of sin and crime. Due care must be taken by the State to preserve the health and life of the prisoner whom the State has deprived of liberty and the opportunity of taking care of himself. A proper classification of prisoners, according to the degree of their criminality, the nature of the crime of which they have been convicted, or the length of time for which they have been sentenced, is now insisted upon by all students of prison dis- cipline. As this subject more nearly concerns the social or legal relations of prisoners rather than their sanitary interests, it is here passed over with a mere mention. The separation of the sexes, necessity of female attendants on prisoners of the same sex, employment of prisoners, and moral reformation of criminals likewise .belong especially to the social aspects of the question, and can find no discussion in this place. Regarding the remaining proposition, however, that which demands that the State shall exercise due care over the prisoner's health, it comprises a question that demands consideration in a text-book on hygiene. There is now a general concurrence of opinion that the State, in depriving any person of liberty, has no right to subject the individual suffering such deprivation to any danger of disease or death. In other words, the State has no right to abbreviate the life of the convict sentenced to prison. This proposition requires that the State see to it that the prisoner is well fed, well clothed, and well housed ; that he shall be well cared for when sick, and that when his term of imprisonment expires he shall be set at liberty, with only such effect upon his normal expectation of life as would result from the ordinary wear and tear of life upon his health. It must be confessed, however, that the State is very far short of attaining this object. The mortality of convicts, even in the. best-regulated prisons, where especial attention is paid to the sanitary requirements of such buildings, is three times as PRISON HYGIENE. 281 great as among workmen in mines, confessedly one of the most dangerous occupations. If insurance companies desired to insure the lives of prisoners, the companies would be obliged, in order to secure themselves against loss, to make the premium equivalent to an advance in age of twenty years. This means that a free person has as long an expectation of life at 40 years as a prisoner has at 20. Attention is again called to the fact that the conditions in the most favorably situated and liberally managed prisons only are here considered. What the results are in other institutions, less favorably constructed and managed, will be apparent from the following brief statement : Mr. George W. Cable has shown l that in some of the prisons in the Southern States, under the vicious lease system, the mortality is eight to ten times greater than in properly con- structed and managed prisons elsewhere. In Louisiana, for example, 14 per cent, of all the prisoners died in 1881 ; and in the convict wood-cutting camps of the State of Texas one-half of the average number so employed during 1879 and 1880 died. The mortality of prisoners is greatest in the second, third, and fourth years of their confinement. In Millbank Prison, in England, the death-rate per 1000 was 3.05 in the first year, 35.64 in the second, 52.26 in the third, 57.13 in the fourth, and 44.17 in the fifth years of imprisonment. The diseases most frequent among prisoners are pulmonary phthisis and diseases of inanition, manifested by general dropsy. Consumption furnishes from 40 'to 80 per cent, of all deaths. When prisoners are attacked by acute febrile or epidemic diseases (small-pox, cholera, dysentery), the mortality is much higher than among persons in a state of liberty. This fatality is due to an aneemic or cachectic condition, which has been called " the prison cachexia," a depravement of constitution which yields readily to the invasion of acute diseases. Prisons should be built upon a healthy site, be properly heated and ventilated, have an abundant water-supply, and 1 Century Magazine, February, 1884. 282 TEXT-BOOK OF HYGIENE. be supplied with facilities for a prompt and thorough removal of sewage. Baths and lavatories should he conveniently ar- ranged in order that thorough cleanliness can be enforced. The problem of feeding prisoners requires careful study. The food should not only be sufficient in quantity and of good quality, but it should be well cooked, and the bill of fare varied often in order to avoid creating a disgust by an everlasting sameness. Prisoners often suffer from nausea and other digestive derangements, brought on solely by the monotonous character of the daily food. " In workshops and sleeping-rooms, dormitories or cells, the cubic air-space allowed to each inmate should not be less than 17 cubic metres, with proper provision for ventilation. The use of dark or damp cells as places o'f confinement is a relic of the barbarism in the treatment of convicts against which John Howard raised his voice so effectively in the last century. An abundance of sunlight should be admitted into every room in which a human being is confined. An important hygienic measure is daily exercise in the open air. It should be regularly enforced, and its modes frequently varied in order that it may not degenerate into a mere perfunctory performance. Punishment for infractions of the prison discipline should be inflicted without manifestation of passion, and only under the immediate direction of some official responsible to the State. It is questionable whether physical punishments, such as whipping, tricing up by the thumbs with the toes just touching the floor, bucking and gagging, and similar barbarities should be permitted under any condition. The permission to exercise such power is extremely liable to be abused by officials. The system of leasing out prisoners to private parties, which prevails in some of the southern United States is vicious in the extreme, because it places the convict under the control of persons not responsible to the State, and, in the majority of instances, morally unfitted to wield the power of inflicting punishment. PRISON HYGIENE. 283 [The following works on prison hygiene and prison reform are recommended to the student : A. Baer, Gefangniss-Hygiene, in von Pettenkofer und Ziemssen's Handbuch der Hygiene, II Th., 2 Abth. Trans. International Peniten- tiary Congress, London, 1882. Trans. National Prison Association, Baltimore, 1872. G. W. Cable, The Convict-Lease System in the South- ern States, Century Magazine. February 1884.] QUESTIONS TO CHAPTER XII. PRISON HYGIENE. How does the mortality of those who are in prison compare with those of the same age who are free? What philanthropists called early attention to the abuses of prisons and prisoners ? What fundamental propositions now practically govern prison legislation ? Why must the State exercise due care over the prisoner's health ? What must the State do to attain this object ? Does it succeed in doing it ? How does the excessive mortality compare with that of dangerous occupations ? How does the expectation of life compare with that of those outside of prison ? What is the mortality where the lease-system obtains ? When is the mortality among prisoners greatest? What diseases are most frequent among prisoners ? What is the effect of acute febrile or epidemic diseases upon prisoners ? To what is this due ? What principles should be observed in prison construction ? What points should be particularly observed regarding the food of prisoners ? How much air-space should be allotted to each prisoner, whether in workshops or cells ? What precautions should be taken against damp- ness and absence of sunlight ? What is another important measure that should be enforced daily ? How should all punishments be inflicted, and what ones should be prohibited ? What can be said of the lease system ? (284) CHAPTER XIII. EXERCISE AND TRAINING. THE healthy functions of the bodily organs can only be maintained by more or less constant use. A muscle or other organ that is unused soon wastes away, or becomes valueless to its .possessor. On the other hand, trained use of the various organs makes them more effective for the performance of their functions. Thus, by practice, the eye can be trained to sharper vision, the ear to distinguish slight shades of sound, the voice to express varying emotions, the tactile sense to accurately appre- ciate the most minute variations of surface and temperature, and the hand to greater steadiness or the performance of difficult and complex feats. The effectiveness of other organs, muscles, or groups of muscles can also be increased by systematic train- ing, as is seen in the athlete and gymnast. PHYSIOLOGICAL EFFECTS OF EXERCISE. When a muscle contracts, the flow of blood through it is increased. Hence, contraction of a muscle, which consumes or converts stored-up energy, at the same time draws upon the cir- culation for a new supply of food-material to replace that con- sumed. The activity of the circulation through a muscle in action results in increased nutrition and growth of the muscle. During muscular action the activity of the respiratory process is increased. A larger quantity of air is taken into the lungs, more oxygen is absorbed by the blood, and an increased elimination of carbon dioxide takes place. The experiments of Fettenkofer and Voit show that, while in a state of rest the average absorption of oxygen in twelve hours amounted to 708.9 grammes, during work the amount reached 954.5 grammes. (285) 286 TEXT-BOOK OF HYGIENE. For the same period the elimination of carbonic dioxide was: during rest, 911.5 grammes; during work, 1284.2 grammes. Upon the circulation muscular exercise likewise exerts a manifest influence. The action of the heart is increased both in force and frequency, the arteries dilate, and the blood is sent coursing through the system more rapidly than when the body is at rest. Cutaneous transpiration is also promoted by muscular exer- cise. It is probable that in this way some of the effete matters in the system are removed, being held in solution and carried through the skin in the perspiration. PHYSICAL TRAINING. There can be no question that systematic training of the muscles has a favorable influence upon health and longevity. Persons who are actively engaged in physical labor, other things being equal, are healthier, happier, and live longer than those whose occupation makes slight demands upon their muscular sys- tem. In default of an active occupation the latter class is forced, if good health is desired, to adopt some form of exercise which will call the muscles into activity. The principal methods of physical training are walking or running, rowing, swimming, and the various, in-door gymnastic exercises. Rapid walking or running is one of the best methods of physical exercise, for, not only are the muscles of the legs and thighs developed, but the capacity of the chest is increased one of the principal objects of physical training. By combining walking with some form of in-door gymnastics, such as practice with dumb-bells, Indian clubs, rowing-machines, or pulley- weights, nearly all the good effects of the most elaborate system of training can be obtained. For the gymnastic exercises various forms of useful labor may be substituted with advantage, such as wood-chopping or sawing, or moderate work at any physical labor. The scheme of studies in our public-school system should PHYSICAL TRAINING. 287 include physical training for both sexes. This is a question not merely of individual, but of national importance. Weak and unhealthy children are not likely to grow up into strong and healthy men and women; and the latter are necessary for the perpetuity of the nation. The time seems to have arrived when physical education should no longer be looked upon as a whim of unpractical enthusiasts and hobby-riders, but as an indispen- sable element in every school curriculum. There is a tendency among instructors in physical training to make their systems too complicated, or dependent upon expen- sive or cumbersome apparatus. This is to be deprecated. Ail the muscles of the body can be called into action by very simple exercises, easily learned and readily carried out. An important preliminary, to all methods of training is a thorough physical examination of the pupil by a competent physician, in order to determine whether certain exercises are allowable. For example, in all organic heart affections exer- cises of a violent character must be interdicted. A boy or man with valvular disease of the heart cannot run, row, or swim with safety. The organ is easily overtasked in this condition and liable to fail in its function. One of the simplest and best methods to cause the pupil to assume a correct position of the body, and to acquire ease and grace in his movements, is to teach him the "setting-up," as practiced in the United States army. 1 In walking, a free, swinging step should be acquired, with the head erect, shoulders thrown back, and chest well to the front, the whole body from the hips upward inclining slightly forward. The clothing should be loose around the upper part of the body, in order not to interfere with the freest expansion of the chest, and to give the lungs and heart ample room for movement. Even in-door gymnastic exercises alone, when prac- ticed under intelligent provision, will accomplish very favorable results, as shown by the following table: 1 Upton's Infantry Tactics. School of the Soldier, Lesson I. 288 TEXT-BOOK OF HYGIENE. TABLE XXYII. Showing Average State of Development on Admission to Gymnasium ; Average State of Growth and Development after Six Months' Practicing Two Hours a Week, and Average Increase During that Time. (Bowdoin College Gymnasium, under Dr. D. A. Sargent. Two Hundred Students from the Classes of 1873 to 1877, inclusive. Average Age, 18.3 Tears.} 1 On Admission. After Six Months' Practice. Average Increase. Height 170.0 c 60.7k 87.5 c 80.6 25.0 27.5 38.7 78.7 48.7 31.2 in. B. 11. 170.6 c 61.6k 91.8 c 82.4 26.8 29.0 40.5 84.4 52.6 33.0 in. g- u. 0.6 ci 900.0 gi 4.3 ci 1.8 1.8 1.5 1.8 5.7 3.9 1.8 n. us. n. Weight Chest (inflated) . Forearm Shoulders ^idth) Thigh ... ... .... Calf .' The table on the following page shows the average rate of increase in development in a two years' and a four years' class in Amherst College, and also the percentage of increase in one four years' class from entrance to graduation. The interest- ing fact has been brought out by Mr. Delabarre that tobacco- smoking has a decidedly deleterious effect upon the rate and percentage of physical development in students. In. weight non-smokers gained 24 per cent, over smokers ; in height 37 per cent., and in chest-girth 42 per cent. OVEREXERTION. . However necessary for the preservation of health physical exercise may be, overexertion should be carefully avoided. Overstrain and hypertrophy of the heart are often the results of excessive exertion. Dr. Da Costa has described a form of ' irri- table " and weak heart occurring especially among soldiers, which he has clearly traced to overexertion. Severe labor and violent athletic exercises have been followed by like serious results. Long-distance pedestrianism has furnished, within recent years, quite a number of individuals who were broken down in health 1 Apparatus used: Weights, 4500 to 6750 grammes; Dumb-bells, 1125 grammes; Indian clubs, 1575 grammes ; Pulleys. OVEREXERTION. 289 TABLE XXYIII. Showing Physical Gains of Students in Amherst College During a Part and During the Whole of the College Course. (Prof. E. Hitchcock, Dr. H. H. Seelye, and Mr. F. A. Delabarre.) GAIN OF Two YEARS' CLASS. GAIN OF FOUR YEARS' CLASS. Per Cent, of Increase in Class of '91. Weight, H 1fi*- Girth, 2.72 Breadth, 2.93 Strength, 25.31 Capacity, 4.00 Metric. English. Metric. English. Weight 2.6 .11 .3 .4 .8 .4 .14 .5 .10 .14 .9 .10 .15 .19 .13 .4 .3 .9 .11 .2 .2 .13 .11 .14 .6 .6 .4 .3 .1 .2 .1 .2 .11 .7 .2 .2 .3 .2 .2 .2 .2 .1 .19 .14 .73 ..30 2.8 b2.6 bl.l .33 .5 .5 1.2 d5.72 .43 .11 .15 .31 .15 .55 .19 .39 .55 .35 .39 .59 .74 .51 .15 .11 .35 .43 .07 .07 .51 .43 .55 .23 .23 .15 .11 .03 .07 .03 .07 .43 .27 .07 .07 .11 .07 .07 .07 .07 .03 .74 .55 4160.9 d.66 a61.7 a 72.7 dll.O dll.O .73.2 5.40 .16 .11 .9 .5 .12 .18 .7 .14 .41 .34 .41 .36 .24 .25 .6 .7 .13 .10 .8 .9 .13 .17 .16 .6 .5 .5 .6 .2 .3 .3 .4 .19 .13 .9 .11 .4 .4 .10 .6 .5 .4 .24 .20 .82 .64 .28 2.3 1.2 .37 .7 .5 3.6 11.8 .63 .43 .35 .19 .47 .7 .27 .55 1.61 1.33 1.61 1.41 .94 .98 .23 .27 .51 .39 .31 .35 .51 .66 .62 .23 .19 .19 .23 .07 .11 .11 .15 .74 .51 .35 .43 .15 .15 .39 .23 .19 .15 .94 .78 180.8 1.41 61.7 81.5 15.4 11.0 219.6 8.9 0.6 1 0.7 1.2 3.3 0.4 1.3 0.5 : 2.5 3.0 1.0 4.1 2.4 3.0 3.1 0.8 1.1 2.8 2.3 0.8 0.8 6.3 6.4 7.8 3.5 3.5 3.3 3.1 0.0 0.6 0.6 k 1.8 3.6 6.4 3.4 1.8 1.1 = 0.8 1.5 1.5 1.1 1.1 1.3 0.6 26.9 -I 27.8 24.0 38.0 . 20.5 26.0 23.7 15.6 4.0 Height Pubes Sitting Girth, Head Neck Chest repose Chest full Belly Hips Right thigh Left thigh Right knee Left knee Right calf Lett calf Right instep Left instep Upper right arm . . . U. R. A. contracted . Upper left arm . . . Right forearm . . . Left forearm Breadth Head Shoulders Waist Hips Right-shoulder elbow . . Lot t-shnulder elbow . . . Left elbow-tip Length, Right foot . . . Left foot Stretch of arms Horizontal length .... Lungs Back Chest dip Chest pull up .... Right forearm .... Left forearm .... Capacity of lungs .... 1 A total average gain 1 of 5.87 per cent. a Kilos, b Units. c Litres, d Pounds, e Cubic inches, and Inches and Tenths. All others, Millimetres, by the excessive strain on the physical organization involved. Cardiac strain is not infrequent among this class. Spasm, in 290 TEXT-BOOK OF HYGIENE. paralysis, or atrophy of muscles sometimes results, when these are exhausted by uninterrupted or excessive exercise. This effect is shown by writers' and telegraphers' cramp, and similar affections. For these reasons it is important that both exercise for health and actual work should be so regulated as to conduce to the individual's benefit, and not to his detriment. [On the subjects embraced in this chapter the following works may be studied with advantage : A. Braynton Ball, : ' Physical Exercise," in Buck's Hygiene and Public Health, vol. i. Win. Blaikie, How to Get Strong and How to Stay so. A. Maclaren, Training in Theo^ and Practice. Hitchcock and Seelye, The Ainherst Anthropometric Manual.] QUESTIONS TO CHAPTER XIII. EXERCISE AND TRAINING. What is absolutely necessary for the maintenance of the healthy functions of the body ? What is the effect of disuse upon any organ ? Of training? What occurs when a muscle contracts ? What is the result of in- creased activity of circulation in a muscle ? What is the effect of mus- cular action on the respiratory process ? What is the difference as to the absorption of oxygen in a state of rest and. during work ? As to the elimination of carbon dioxide and water ? What is the effect of muscular action upon the circulation ? Upon the cutaneous transpiration ? What is the effect of systematic training upon health and longevity ? What are some of the principal and best methods of physical training? What is one of its most important objects? How may the various methods be combined with benefit? What should be included among the studies and work of all public schools ? For what purposes ? What is the tendency among instructors in physical training? Is this necessan", or not? Why? What is an important preliminary to all methods of training? Why ? How may a pupil be taught to assume and maintain a correct position and carriage of the body ? How should a person walk ? What attention should be given to the clothing worn during exercise? What will be some of the results of systematic physical training properly pursued ? What are some of the results of overexertion ? Does it make a difference whether the exercise is too long uninterrupted or whether it is excessive in amount and character ? (291) CHAPTER XIV. BATHS AND BATHING. THE most important sanitary object of bathing is cleanli- ness. A secondary object of the bath is to stimulate the func- tions of the skin, and to produce a general feeling of exhilaration of the body. Baths are used of various temperatures. A cold bath has a temperature of from 4 to 24 C. (40 to 75 F.) ; a tepid bath from 24 to 30 C. (75 to 85 F.), a warm bath from 30 to 38 C. (85 to 100 F.), and a hot bath from 38 to 43 C. (100 to 110 F.). Tepid, warm, or hot batJis are used principally as cleansing agents or as therapeutic measures. They cause dilatation of the cutaneous capillaries, diminish blood-pressure, and reduce nervous excitability. The hot bath is also a method for restor- ing warmth to the body in certain cases of shock, or to remove the immediate effects of injurious exposure to low temperature. The so-called Russian and Turkish baths, so popular in the larger cities of this country, are modifications of vapor- and hot- air baths, or rather combinations of these with cold baths. The Turkish bath is especially to be recommended for its depurative and invigorating effects. Cold baths are used not merely for their cleansing effects, but principally for their stimulating effects upon the system. When first plunging into a cold bath there is usually a moment- ary shock ; the respiration is gasping, and the pulse is increased in frequency. These symptoms disappear in a few moments, however, and reaction follows. To a healthy person a cold bath is a delightful general stimulant, removing the sense of fatigue after physical exertion and causing an extremely refreshing sensation throughout the body. (293) 294 TEXT-BOOK OF HYGIENE. As a therapeutic measure, the cold bath has a wide field of usefulness. For the reduction of the bodily temperature in fevers and inflammatory diseases, and especially in heat-stroke, it is more prompt and effective than any other agent at the com- mand of the physician. Sea-Batliing. The most stimulating form of the cold bath is doubtless the salt-water bath as taken at the sea-shore. The revulsive effect of the impact of the waves and breakers upon the skin and the stimulation due to the saline constituents of the sea-water heighten the invigorating effects of the simple cold bath. The beneficial results of sea-bathing are, however, not entirely due to the bath, but are to a great degree dependent upon the bracing air of the sea-shore, absence of the care and anxieties of business, and the temporary change in food and habits that a residence at the sea-side involves. Nevertheless, salt-water baths are more stimulant to the skin than those of simple water, and part of the good effects of sea-bathing can often be obtained from a salt-water bath taken at home. The following mixture of salts dissolved in about 125 litres of water for one bath makes a fairly good substitute for a sea-bath : Take of Chloride of sodium (common salt), . . .4 kilogrammes. Sulphate of sodium (Glauber's salt), . . 2 " Chloride of calcium, kilogramme. Chloride of magnesium, . . . ' . . 1^ kilogrammes. There is a prevalent popular belief that it is extremely dan- gerous to enter a cold bath when heated or perspiring. The author is of the opinion that this belief is erroneous. The stim- ulant and bracing effects of the cold bath are most manifest if it be taken while the individual is very warm or bathed in perspira- tion. Several years ago the author made a series of observations upon himself to determine the effects of the cold bath when the body was very warm. Every afternoon a free perspiration was provoked by a brisk walk of about 2 kilometres in the sun. As soon as the clothing could be cast off, and while the body was still freely perspiring, a plunge was taken into a fresh-water bath of about 15.5 C. (60 R). No ill results followed; on RULES FOR BATHING. 295 the contrary, the sensation immediately following the bath, and for six or eight hours afterward, was exceedingly pleasant. The health remained perfect, and the weight decidedly increased during the two months the practice was continued. There is probably no danger to a healthy person in this practice, but it is considered advisable to immerse the head first (" take a header "), to avoid increasing the blood-pressure in the brain too greatly, which might result if the body were gradually immersed from the feet upward. RULES FOR BATHING. The following series of rules have been issued by the English Royal Humane Society, and are all worth observing by bathers : " Avoid bathing within two hours after a meal. Avoid bathing when exhausted by fatigue or from any other cause. Avoid bathing when the body is cooling after perspiration. Avoid bathing altogether in the open air, if, after having been a short time in the water, there is a sense of chilliness, with numbness of the hands and feet; but bathe when the body is warm, provided no time is lost in getting into the water. Avoid chilling the body by sitting or standing undressed on the banks or in boats, after having been in the water. Avoid remaining too long in the water, but leave the water immediately if there is the slightest feeling of chilliness. The vigorous and strong may bathe early in the morning on an empty stomach. The young, and those who are weak, had better bathe two or three hours after a meal ; the best time for such is from two to three hours after breakfast. Those who are subject to giddiness or faintness, or suffer from palpitation or other sense of discomfort at the heart, should not bathe without first consulting their medical adviser." To these instructions may properly be added that a warm or hot bath should be avoided, if the person is liable to ex- posure to cold within a few hours after the bath; that women should, as a rule, not take a cold bath while menstruating, or during the last two months of pregnancy ; and that persons 296 TEXT-BOOK OF HYGIENE. suffering from organic heart disease should especially avoid surf- bathing. After bathing the body should be thoroughly dried with soft towels, otherwise eczematous eruptions are liable to follow in the parts subject to friction from opposing surfaces of the skin, as in the groins, the perinaeum and inner surface of the thighs, the armpits, or the under surface of the breasts in women in whom these organs are large and pendant. Friction of the skin with a coarse towel, or so-called "flesh-brush," is a popular practice, but is not to be universally commended. The hypersemia of the surface thus produced may sometimes induce cutaneous diseases (erythema, eczema, psoriasis) in those predisposed. DANGERS OF COLD BATHING. One of the most serious dangers of cold bathing, but which is not sufficiently appreciated, is the tendency to nausea and vomiting if the stomach contains much food. There can be no doubt that many of the cases that are called " cramp," and which frequently result in drowning, are due to this cause. 1 Cramps of the various muscles sometimes occur, rendering the bather helpless, and if in deep water he is liable to drown before assistance can reach him. HOW TO RESTORE THE APPARENTLY DROWNED. In drowning death takes place by asphyxia. The respira- tion is arrested by the submersion of the head, the carbonized blood gradually poisons the system, and the heart ceases to beat. So long as the heart will react to its appropriate stimulus the person may be restored to life. The first thing to do, therefore, after a recently-drowned person is taken out of the water, is to attempt to re-establish the arrested respiration. Several methods are in use for this purpose. Sylvester's is one of the simplest. It is as follows : 1 So far as the author is aware, Dr. John Morris, of Baltimore, first called especial atten- tion to this source of danger. HOW TO RESTORE THE APPARENTLY DROWNED. 297 The body being placed on the back (either on a flat sur- face or, better, on a plane inclined a little from the feet upward), a firm cushion or similar support (a coat rolled up will answer) should be placed under the shoulders, the head being kept in a line with the trunk. The tongue should be drawn forward to raise the epiglottis and uncover the windpipe. The arms should be grasped just above the elbows and drawn upward until they nearly meet above the head, and then at once lowered and re- placed at the side. This should be immediately followed by pressure with both hands upon the belly, just below the breast- bone. The process is to be repeated fifteen to eighteen times a minute. Several years since the Michigan State Board of Health published a method which is comprehensive, effective, easily understood, and readily carried out. This method has also been adopted by the United States Life-Saving Service. The follow- ing are the details of the Michigan method: Rule 1. Remove all the obstructions to breathing. In- stantly loosen or cut apart all neck- and waist- bands ; turn the patient on his face, with the head down hill ; stand astride the hips with your face toward his head, and, locking your fingers together under his belly, raise the body as high as you can with- out lifting the forehead off the ground, and give the body a smart jerk to remove mucus from the throat and water from the windpipe, hold the body suspended long enough to slowly count one two three four -five, repeating the jerk more gently two or three times. Rule 2. Place the patient on the ground face downward, and, maintaining all the while your position astride the body, grasp the points of the shoulders by the clothing ; or, if the body is naked, thrust your fingers into the armpits, clasping your thumbs over the points of the shoulders, and raise the chest as high as you can without lifting the head quite off the ground, and hold it long enough to slowly count one two three. Replace him on the ground with his forehead on his flexed arm, the neck 298 TEXT-BOOK OF HYGIENE. straightened out, and the mouth and nose free ; place your elhows against [the inner surface of] your knees and your hands upon the sides of his chest over the lower ribs, and press down- ward and inward witfy increasing force long enough to slowly count one two. Then suddenly let go, grasp the shoulders as before, and raise the chest ; then press upon the ribs, etc. These alternate movements should be repeated ten or fifteen times a minute for an hour, at least, unless breathing is restored sooner. Use the same regularity as in natural breathing. Rule 3. After breathing has commenced restore the animal heat. Wrap him in warm blankets, apply bottles of hot water, hot bricks, or anything to restore heat. Warm the head nearly as fast as the body lest convulsions come on. Rub- bing the body with warm cloths or the hands and slapping the fleshy parts may assist to restore warmth and the breathing also. If the patient can surely swallow, give hot coffee, tea, milk, or a little hot sling. Give spirits sparingly, lest they produce depression. Place the patient in a warm bed, and give him plenty of fresh air. Keep him quiet. Beware ! Avoid delay. A moment may turn the scale for life or death. Dry ground, shelter, warmth, stimulants, etc., at this moment are nothing artificial breathing is everything is the one remedy all others are secondary. Do not stop to re- move wet clothing. Precious time is wasted, and the patient may be fatally chilled by exposure of the naked body, even in summer. Give all your attention and efforts to restore breath- ing by forcing air into, and out of, the lungs. If the breathing lias just ceased, a smart slap on the face or a vigorous twist of the hair will sometimes start it again, and may be tried inci- dentally. Before natural breathing is fully restored, do not let the patient lie on his back unless some person holds the tongue forward. The tongue by falling back may close the windpipe and cause fatal choking. Do not give up too soon ; you are working for life. Any PUBLIC BATHS. 299 time within two hours you may be oh the very threshold of success without there being any sign of it. 1 PUBLIC BATHS. In all large cities and towns provision should be made for free public baths, conducted under official supervision, and for the especial use and benefit of the poorer classes. General cleanliness is not merely a factor in the preservation of the public health, but there is good reason to believe that the cause of good order and decency would likewise be promoted by furnishing the public the means of easily and cheaply keeping clean. Several of the larger cities in the country have estab- lished public baths upon a limited scale, and these have been very popular and have doubtless been of great benefit. The author has shown 2 that about five-sixths of the inhabitants of the large cities in the United States have no facilities for bathing except such as are afforded by a pail of water and sponge, or in summer the proximity of some body of water easily accessible. The most economical and best form of bath for public use would doubtless be the needle or rain bath recom- mended by the author in the paper referred to. Mr. W. P. Gerhard has also recently strongly advocated this form of bath. 1 Report of Michigan State Board of Health, 1874, pp. 91-99. 3 Address in State Medicine, Journal American Medical Association, July 2, 1887. QUESTIONS TO CHAPTER XIV. BATHS AND BATHING. What is the most important object of bathing? For what other purposes may baths be taken ? What are the respective temperatures of so-called cold, tepid, warm, and hot baths ? What are the physiologi- cal effects of the last three ? In what surgical emergencies may the hot bath be used ? For what are cold baths used ? What are their physio- logical effects ? How may the cold bath be used therapeutic-ally ? What is the most stimulating form of cold bath ? To what are its beneficial effects due? How may a salt-water bath be prepared at home ? Is there any danger to the healthy in cold bathing while the body is per- spiring freely ? What precaution should be taken before entering a cold bath ? What rules may be laid down for bathing in the open air ? When is the best time for bathing? Who should not bathe without pre- vious medical advice? When should hot baths not be taken? What should follow all baths ? What is one of the most serious dangers of cold bathing ? How does death take place in drowning ? What is the indication that one apparently drowned may still be restored to life ? Describe Sylvester's method of artificial respiration. What is the method adopted by the United States Life-Saving Service ? What is essential after breathing has been re-established ? How should spirits be given ? How long should efforts to restore respiration be continued ? What is to be avoided ? What are some of the arguments in favor of public baths in large cities ? What is the most economical form of bath for public use ? (300) CHAPTER XV. CLOTHING. THE primary object of clothing is the protection of the body against the injurious influences of heat, cold, and moist- ure. Secondarily, the moral sense of civilized communities demands that the nude human body shall not be exposed in public. Hence, there are moral as well as sanitary reasons for the wearing of clothing ; only the latter can be considered in this place. Bodies radiate or absorb heat accordingly as they are sur- rounded by a medium having a lower or higher temperature than themselves. In order, therefore, to avoid chilling of the human body, if exposed to a temperature below 37 C. (98 F.), clothing must be worn to prevent or retard radiation of the body-heat. Exposure of the unprotected body to a low tem- perature would not merely cause chilling of the surface, owing to the rapid loss of heat, but would incidentally produce con- gestion of internal organs by causing constriction of the super- ficial capillaries. Clothing is also worn as a protection against great heat. The head, especially, needs protection from the sun's rays. CLOTHING MATERIALS. The materials from which clothing is made are, princi- pally, cotton, linen, wool, silk, and the skins of animals. Of these, probably the most universally used is cotton. It is cheap, durable, does not shrink when wet, absorbs little water, and conducts heat readily. It is therefore especially valuable for summer garments, allowing rapid dissipation of the body-heat and evaporation of the perspiration. Linen conducts heat even better than cotton, and is for (301) 302 TEXT-BOOK OF HYGIENE. this reason largely used for summer clothing. Its principal advantage over cotton is that it is more durable and less harsh to the skin. Wool absorbs water readily and is a bad conductor of heat. It is therefore valuable as a winter garment, retarding radiation from the body. Woolen undergarments should be worn at all seasons, in order to prevent too rapid changes of the surface, and so invoking diseases depending upon chilling of the body. Clothing of pure wool (flannels) is liable to irritate the skin of some persons. A mixture of wool and cotton, known as " Saxony wool," is softer and less irritating, and makes a serv- iceable substitute for pure wool. Silk is often used for undergarments. It is light, soft, and a bad conductor of heat. The skins of animals, with the fur on, are often used for outside clothing. They furnish great protection against severe cold. The skin is impermeable to wind and rain, while the thick, pilous covering of fur retards to a very great degree the radiation of heat. In British America, the Northwestern States and Territories, and in the Arctic regions, the use of skin clothing is necessary for comfort. As a protection against moisture (rain and snow) rubber cloth is used for overcoats, etc. While it serves effectually in keeping out the rain, it prevents evaporation of the perspiration, increasing the liability to chill, and rendering the person wear- ing it very uncomfortable, except in cold weather. Leather is used almost exclusively in the manufacture of foot-wear. It is sometimes used, however, for other articles of clothing, such as coats, trowsers, etc. It furnishes most effective protection against cold. The color of the clothing is of great importance. Ex- posed to the sun, white wool or silk absorb very little more heat than linen or cotton, but the same material, of different colors, when exposed to the sun's rays, exhibits marked differ- ences in absorptive capacity. The following table shows the CLOTHING. 303 results of some experiments of Pettenkofer. The material used was cotton shirting of the colors named : White absorbed 100 heat units. Light Sulphur Yellow absorbed . . 102 " " Dark Yellow absorbed .... 140 " " Light Green absorbed .... 155 " " Turkey Red absorbed . . . . 165 " " Dark Gueen absorbed . . . . 168 " " Light Blue absorbed 198 " " Black absorbed 208 " " When protected from the sun's rays, however, the material becomes important and the color is of little consequence. Wool, being a bad conductor of heat, retards radiation from the body, and is hence the best material for winter clothing. Gases and vapors, probably also disease-germs, are ab- sorbed by clothing, and may be thus conveyed from place to place. It has been found that woolen clothing possesses this power of absorption to a much greater degree than linen or cotton. The bad odor of a crowded room or of tobacco-smoke frequently clings to woolen garments for days, although they may be exposed constantly to the air during the interval. It would be advisable, therefore, that physicians attending infec- tious diseases, hospital attendants and nurses, should wear linen or cotton clothing instead of woolen. Clothing should be made to jit properly. It should not restrain muscular movements, obstruct the circulation, or com- press organs. Hence, corsets, belts, and garters are to be con- demned. It is a fact of common observation that moderately loose clothing is warmer than close-fitting. Especial attention should be given to the shape and fitting of foot-wear. Boots and shoes are usually made with little regard to the physiological anatomy of the foot, and as a result the feet of most Americans are deformed, beauty and usefulness being in a great degree sacrificed to the Moloch of fashion. 1 1 See a practical paper by Dr. Benj. Lee, A Shoe That Will Not Pinch, in Sanitarian for June, 1884, p. 493. 304 TEXT-BOOK OF HYGIENE. Dyes used for coloring fabrics are sometimes poisonous. The author lias repeatedly seen troublesome eruptions, and even ulcerations of the legs, from wearing stockings dyed with aniline compounds. By appropriate treatment clothing can be made non- inflammable. Tungstate and phosphate of soda are used to reduce the inflammability of fabrics. The addition of 20 per cent, of tungstate of soda and 3 per cent, of phosphate of soda to the starch-sizing used for stiffening linen is effective. The material is not injured by it, and a smooth surface and polish can be obtained under the hot iron. Prof. Kedzie has recom- mended borax for the same purpose. He says : " The simplest and easiest way to make your cotton and linen fabrics safe from taking fire is to dissolve a heaped teaspoonful of powdered borax in ^ pint of starch solution. It does not injure the fabric, imparts no disagreeable odor, and interferes in no way with the subsequent washing of the goods. It does not prevent the formation of a smooth and polished surface in the process of ironing. Borax can be found in every village, and is within the reach of all. It is a cheap salt, and its use for this purpose is very simple." 1 [The following works may also be studied to advantage: Hammond, Hygiene, p. 579. L. Meyer, Kleidung, in Realenc} r clo- psedie d. ges. Heilk., Bd. VII, p. 446. Yan Harlingen, Care of the Person, in Back's Hygiene and Public Health, vol. i.] 1 Michigan State Board of Health, p. 181. 1880. QUESTIONS TO CHAPTER XV. CLOTHING. What is the primary object of clothing? What are some of the secondary objects? What are the probable results of exposing the unprotected body to low temperature ? What part of the body needs special protection against heat ? What are the principal materials from which clothing is made? Which of these is most universally used ? Why ? In what respect is linen superior to cotton? Why are cotton and linen not suited for winter wear or cold climates ? Why are silk and wool better for such uses ? Why should wool be worn next the skin? What gives silk its value ? Why are furs so warm? What are some of the objections to the use of rubber clothing ? For what is leather chiefly used ? Of what importance is the color of the clothing? What colors absorb least and what ones most heat ? If protected from the sun's rays, which is the most important in the absorption of heat, material or color? What deleterious or harmful matters are absorbed or cling to cloth- ing? What kinds of clothing have the greatest power of absorption.? What precautions should those attending cases of infectious diseases observe ? Why should clothing fit properly? What parts of the clothing should not be too tight ? What disturbances may result from the wear- ing of clothing that is too tight ? How may improperly-dyed clothing create trouble ? How may clothing be rendered practically non-inflam- mable ? (305) CHAPTER XVI. DISPOSAL OF THE DEAD. WHEN life is extinct in the animal body decomposition begins. This may be either putrefactive or non-putrefactive. The difference between the two processes has been explained by Liebig. In putrefaction of organic matters only the elements of water take part in the formation of the new compounds which result, while in non-putrefactive decomposition or decay the oxygen of the air plays an important part. Putrefaction can go on under water, while decay can only take place when the supply of free oxygen is abundant. The prompt removal of the bodies of the dead from the immediate vicinity of the living is a matter of prime sanitary importance. If death results from a contagious or an infectious disease, the necessity for the removal of the corpse is evident. But, even where there is no danger of propagation of infectious disease, the products of putrefaction and decay may give rise to serious derangements of health if allowed to pollute the air. The chief methods of disposal of the dead are burial in the earth, entombment in vaults, and cremation. INTERMENT. The most common method of sepulture is burial in the earth. The corpse is usually inclosed in a case (coffin) of wood or metal, and buried from 1 to 2 metres deep. Here decom- position sets in, which is at first putrefactive and later on non- putrefactive. In the course of several years, from five to ten, the entire body, with the exception of the bones, has usually disappeared and become converted into a dry mold. The soil of a burial-ground should be dry and porous, so (307) 308 TEXT-BOOK OF HYGIENE. as to be easily permeated by the air. In a sandy or gravelly soil the decay of a corpse is much more rapid than in a moist, clayey soil. In the latter the bodies more readily undergo putrefaction, or become converted into a substance termed adi- pocere. It has been calculated that in a gravelly soil the decay of a corpse advances as much in one year as it would in sand in one and two-thirds, and in clay in two to two and one-third years. The decay of the dead bodies is principally (if not entirely) dependent upon the presence of living vegetable organ- isms. If the access of free oxygen is prevented, the bacteria of putrefaction will thrive and cause putridity. If, however, the soil is loose, porous, and easily permeable by the air, the bacteria of decay will be present and produce their charac- teristic effects. The barometric pressure seems to affect the decomposition of dead bodies. For example, at the refuge of St. Bernard, in the high Alps, the bodies of those dying are not buried, but exposed to the air, where they undergo a drying, shrinking, and mummification instead of putrefaction or decay. Alternate saturation and drying of the soil promotes the rapidity of decay. Certain occupations are said to produce changes in the tissues which resist decay. Thus, tanners are supposed to resist the final changes of the tissues longer than persons of other occupations. Shakespeare makes the grave-digger in Hamlet say: "A tanner will last you nine years." The corpses of those poisoned by phosphorus, arsenic, sulphuric acid, or corrosive sublimate also decay more slowly than those of cases of infectious diseases. All the tissues may be converted into adipocere, but in the large majority of cases only the fat and connective tissue undergo this change. SUPPOSED DANGERS OF BURIAL-GROUNDS. Popular sanitary literature teems with supposed instances of the injurious influences of cemeteries upon the health of SUPPOSED DANGERS OF BURIAL-GROUNDS. 309 persons living in their vicinity. An unprejudiced consideration of the subject shows, however, that there is no trustworthy evi- dence that any of the gases exhaled by decaying or putrefying bodies are injurious to health. The air of closed burial-vaults may be dangerous from the large proportion of carbon dioxide contained in it, but the other gaseous products of decomposition have no deleterious effects. The dangers to health from the proximity of cemeteries are doubtless very much exaggerated. Pettenkofer and Erismann have shown that a single large privy- vault, containing about 17 cubic metres of excrement, gives off nearly as large an amount of putrefactive gases in the course of one year as is exhaled by a burial-ground containing 556 decomposing corpses in ten years. Where bodies are properly buried, and the ground is not overcharged by corpses, it is not probable that infectious diseases are propagated from interred bodies. There are no facts on record which show that such an event has occurred. The dangers of pollution of water by cemeteries have also been much overestimated. The purifying power of soil-strata, through which the water is compelled to percolate before reach- ing the well after becoming charged with the products of decom- position, is in most cases sufficient to remove all deleterious matters. Cemeteries should not be located within a city, but must be easily accessible. The soil should be dry gravel or sand, with a low ground-water level. The graves need not be deeper than 1^ metres to the top of the coffin. ENTOMBMENT IN VAULTS. Burial-vaults in churches or in the open air should be discountenanced. The gases of decomposition are given off directly to the air without the modifying power of the soil, and often constitute a nuisance, even if not deleterious to health. Entombment in vaults or crypts has not a single favorable circumstance to recommend it. 310 TEXT-BOOK OF HYGIENE. CREMATION. Within recent years the rapid incineration of the dead in properly-constructed furnaces has been frequently recommended. In the United States a cremation furnace was built several years ago at Washington, Pa., by the late Dr. J. C. LeMoine. Among the remains of those cremated were those of the late Dr. Samuel D. Gross, the distinguished surgeon. The practice has not gained very many adherents, however, although cremation societies have been organized and furnaces built in several of the cities throughout the country. Aside from the objections urged by the more conservative classes, who desire to adhere to the time-honored custom of interment, serious legal objections have been brought forward. In cases where poisoning is suspected some time after death, the cremation furnace would have destroyed every evidence of crime, and conviction of a criminal poisoner could not be obtained. The real advantages of cremation, such as rapid destruction of a corpse, economy of space in keeping the remains, and avoidance of pollution of the soil by decaying bodies, and pos- sible pollution of air and water, are more than counterbalanced by the expense and the medico-legal objection mentioned. From a sanitary point of view, cremation is not necessary in this country. A proper regulation of cemeteries will prevent any possible dangers to the living from pollution of the air, soil, or water by the decaying remains of human beings. INTERMENT ON THE BATTLE-FIELD. After battles, the disposal of the bodies of the slain is often a serious problem. Naegeli proposes the following method of interment : After selecting the place of burial, the sod and layer of humus are removed from a sufficiently large surface and thrown to one side. The corpses are then laid upon the denuded place, and the layers of corpses separated by sand, gravel, or fine brush-wood. A trench is then dug around the pile of dead and the soil gained is thrown over the corpses until they are INTERMENT ON THE BATTLE-FIELD. 311 covered to a depth of 1 metre, when the humus and sod are placed over the whole. This furnishes a dry grave in which decay rapidly takes the place of putrefaction, and the corpses soon molder away. The same procedure may be followed in cases of epidemics where the number of deaths is too great to properly bury them in single graves. QUESTIONS TO CHAPTER XVI. DISPOSAL OF THE DEAD. What is the difference between putrefactive and non-putrefactive decomposition ? Why must the dead be removed from the living? What are the chief methods of disposal of the dead? Which is the most common ? Why should the soil of burial-grounds be dry and porous ? Upon what is the decay of, dead bodies dependent ? What is the usual length of time required for the decay of a human body? What may affect the length of this period ? What changes other than decay may the body undergo ? Is there any evidence that the air from cemeteries is dangerous to health ? In what way may the air from a closed burial-vault be detri- mental? Is it probable that infectious disease-germs are disseminated from dead bodies ? Is the pollution of water by cemeteries probable ? What agents serve to prevent this ? Where should cemeteries be located, however ? Why should entombment in vaults be discountenanced ? What are the advantages of cremation? What are the objections to it ? Is it necessary, from a sanitary point of view, in this country ? How may the bodies of the dead be interred after battles, or in case of very fatal epidemics ? What are the advantages of this method ? (312) CHAPTER XVII. THE GERM THEORY OF DISEASE. THE ruling doctrine in the pathology of the present day is the germ theory of disease. Based upon the doctrine of omne minim ex vivo, and supported by strong experimental and clinical evidence, it is accepted by the great majority of physicians. Its advocates claim that the large class of diseases known as con- tagious or infectious are all due to the presence in the blood or tissues of minute organisms, either animal or vegetable. Many other diseases, not at present included in the above class by general pathologists, are also believed, by the adherents of the germ theory, to be caused in the same way. The following con- stitutes a brief review of the most prominent facts in the history of the doctrine : The doctrine of the vital nature of the contagium of dis- ease the contagium animatum of the older writers was held in a vague way by many of the physicians of the past, but it was not until the latter part of the last century that the theory took definite shape. In the works of Hufeland, Kircher, and Linne the idea is expressed with more or less directness that the propa- gation of infectious diseases depends upon the implantation of minute independent organisms into or upon the affected indi- vidual. This hypothesis was, however, first clearly enunciated and defended with great force by Henle in 1840. Three years earlier, Cagniard de la Tour and Schwann had established a rational basis for the theory by their observations upon the yeast- plant and its relation to fermentation.' In 1835 Bassi had dis- covered in the bodies of silk-worms affected by muscardme, a disease of these insects which proved very destructive, a para- site which was soon shown to be the cause of the disease. Within the next few years, Tulasne, DeBary, and Kuehn (313) 314 TEXT-BOOK OF HYGIENE. proved that certain fungi were the causes of the potato-rot and other diseases of plants. Schoenlein, Malmsten, and Gruby, between 1840 and 1845, demonstrated that those skin diseases of man classed as the tinece were due entirely to the action of vegetable parasitic organisms. Up to this time the germ theory, as now accepted, had received no support from experiments. All the diseases claimed as parasitic were purely local ; so far as the parasitic nature of the general diseases was concerned, all was hypothetical. In 1849, Guerin Meneville discovered a corpuscular organism in the blood of silk-worms affected by the pebrine, which was later proven by Pasteur to be the true cause of this destructive dis- ease. Pollender, in 1855, and Brauell, in 1857, found numer- ous minute rod-like organisms (bacteria) in the blood of animals dead from splenic fever. In 1863 Davaine investigated the subject more fully, and showed beyond doubt that the little organisms discovered by Pollender were the true cause of splenic fever, or anthrax. The more recent researches of Robert Koch upon the history of these bacteria or bacilli of splenic fever have removed all doubt of their etiological significance. In 1883 the last-named observer startled the medical world by the assertion that consumption or tuberculosis was a disease of microbic origin, and dependent upon the presence, in the affected tissues, of an organism whicli he named bacillus tuber- culosis. Much controversy arose upon this point, but Koch fortified his position so strongly with proofs, both experimental and clinical, that it may now be regarded as fully demonstrated. Koch has likewise shown (1885) that Asiatic cholera is due to a bacterial organism, termed by him the " comma bacillus," from its shape. It is generally regarded by bacteriologists, how- ever, to belong to the class of organisms known as spirilla, and not to the bacilli. Eberth discovered the bacillus which is now generally accepted as the cause of typhoid in 1880 ; Fehleisen, the micrococcus of erysipelas in 1883; Obermeier, the spirillum of relapsing fever in 1868; Schutz and Lofner discovered the THE GERM THEORY OF DISEASE. 315 bacillus of glanders in 1882 ; Neisser announced the discovery of the micrococcus of gonorrhoea in 1879. The bacillus of leprosy was discovered by Hansen in 1879. The micro-organ- isms of malaria (oscillaria malariae), which are believed to be animal organisms, were discovered by Laveran in 1881. This organism is different from the bacillus malarice of Klebs and Tornnmsi-Crudeli, which possesses no pathological significance. Pneumonia may also be regarded as a microbic disease, since Sternberg, Weichselbaum, and Frankel have shown the constant presence of the micrococcus Pasteurii in the sputa in that disease. In 1887 Nicolaier and Rosenbach proved that tetanus is due to a bacillus. The careful observations and researches of the investigators mentioned, as well as of many others who have worked earn- estly in this field, have established the germ theory of disease upon a secure foundation. For the diseases mentioned the parasitic origin may be accepted as fully proven. For a number of others, among which may be mentioned small-pox, yellow fever, diphtheria, scarlet fever, typhus fever, measles, hydrophobia, etc., the etiological connection between the disease and certain hypo- thetical organisms not yet discovered appears probable. In connection with the germ theory there has arisen of late a very important question in its bearing upon preventive medi- cine. This is the value of the so-called protective inoculations against infectious diseases. The protective influence of vacci- nation against small-pox is firmly established by indubitable evidence. Within the last three or four years a procedure in- troduced by Pasteur to protect animals against certain fatal in- fectious diseases, such as splenic fever, fowl-cholera, and rabies, has claimed much attention. Pasteur's observations were first made upon the disease termed chicken-cholera. He found that- the blood of the dead fowls, or of those attacked by the disease, swarmed with bacteria. Inoculation of healthy fowls with this diseased blood, or with the bacteria alone, carefully freed from all animal fluids, produced the same disease. The bacteria were therefore assumed to be the cause of the disease. The 316 TEXT-BOOK OF HYGIENE. investigator then took a quantity of these bacteria and " culti- vated " them through a number of generations, using sterilized chicken-broth as a culture medium. Fowls inoculated with the result of the last cultivation were still attacked by the same symptoms, but in a very mild degree, and almost uniformly recovered from the disease. On subsequent inoculation with infected blood no effect was produced upon the " vaccinated " fowls, while the same blood introduced into fowls not " pro- tected " by the previous inoculation produced its customary fatal effect. Pasteur and others repeated these experiments with the organisms found in the blood in splenic fever and obtained similar results. Inoculations made with cultivations from the spinal cord of animals suffering from rabies have also been claimed as protective against this disease and hydrophobia. These protective inoculations have been made upon large num- bers of sheep and cattle within the past three years, and with very remarkable success. Recently, however, it has been shown that the protection afforded by the inoculation is a very tem- porary one, and that after a variable but brief interval the pro- tected animals are again liable to be fatally attacked by the disease. The opinion seems to be justified that cultivation pro- duces only a temporary degeneration of the bacteria, which rapidly disappears when the organisms are again brought in relation with their proper nutritive fluid. The " protective in- oculations " produce a mild attack of the disease, \vhich is for a time a bar against a second attack; but the effect soon wears off, leaving the animal in its pristine condition of receptivity toward the infective material. [The following works on this subject are recommended to the student : Sternberg and Magnin, The Bacteria; second edition. Fluegge, Fermente und Mikroparasiten, in von Pettenkoffer und Ziemssen's Handbuch d. Hygiene.] QUESTIONS TO CHAPTER XVII. THE GERM THEORY OP DISEASE. What is meant by the germ theory of disease? When did this doc- trine first take definite shape ? When was it first clearly enunciated, and by whom? What basis was there then for it? What subsequent evi- dence soon developed? What was the first evidence of the parasitic nature of general diseases ? Who discovered and who first demonstrated the true cause of anthrax ? Who proved tuberculosis to be of microbic origin ? When ? What other diseases are now known to be caused by specific micro-organisms ? What others are probably due to a like cause ? What effect has the establishing of the germ theory upon preventive medicine ? What is meant by protective inoculation ? What evidence is there that this is possible How do disease germs produce their char- acteristic effects upon the system ? How may the inoculating material be prepared ? What are some of the theories regarding the method by which susceptible animals or persons are rendered immune? Does the protection by inoculation seem to be permanent ? (317) CHAPTER XVIIL CONTAGION AND INFECTION. THE adjectives "contagious" and "infectious" are used to designate certain diseases which are propagated by immediate contact, or through the intervention of some other medium, from the sick to the healthy. The matters in which reside the mor- bific power are now believed by many to be vegetable organisms, but not a few pathologists hold to the view that the real con- tagia, or disease-bearing agents, are modified animal cells or abnormal fluids. The differentiation between contagion and infection is not easy. Many of the diseases commonly called contagious are also infectious ; that is, they are propagated not merely by direct contact, but also by air, water, or food which may have become infected with the morbific agents. Syphilis, for example, may be regarded as simply a contagious disease ; at the present day, at least, we cannot conceive syphilis to be propagated by breath- ing infected air or drinking water contaminated with the poison of syphilis. Cholera, typhoid, and yellow fevers, on the other hand, are examples of infectious diseases, neither of them being directly contagious, but conveyed from sick to well through the medium of contaminated air, water, or food. Between these two stand small-pox and typhus fever (and perhaps the other exanthemata), which are not merely contagious, but infectious also. There is still a third class of acute diseases not properly included in either of the classes mentioned. This is the class of miasmatic diseases, of which malarial fevers are the type. Ac- cording to recent observations, pneumonia and epidemic influenza ought, perhaps, to come in this class. The contagious and infectious diseases are of particular (319) 320 TEXT-BOOK OF HYGIENE. interest to sanitarians, because it is believed that by judicious carrying out of sanitary measures they can be prevented. Hence they are sometimes termed preventable diseases. Another pecu- liarity of the infectious diseases is that they usually occur in groups of cases. Thus, small-pox, measles, scarlet fever, typhus fever, diphtheria, and others of the class do not occur sporadi- cally, as it is termed ; that is to say, it rarely happens that only one case of small-pox is observed in a locality, unless active measures are at once taken to stamp it out. Usually a number of cases occur successively, and in most instances the succeeding cases can be traced ultimately to the first case. Contagious and infectious diseases frequently appear as epidemics. Authorities differ as to the proper definition of an epidemic; that is, given the population of a place, how many cases of an infectious or contagious disease are necessary before the disease can be considered epidemic at such place. The following formula was given by the New Orleans Medical and Surgical Association in response to the query, "Under what cir- cumstances is it proper to declare such diseases (diphtheria, scarlet fever, measles, small-pox, yellow fever, etc.) epidemic in a place]" The answer given is that the disease should be declared epidemic when the number of cases should reach these proportions 1 : For a population of 100 ... 5 per cent. " " " 500 ... 4 " " " " " 2,000 to 5,000 . 221 thousand. " " " 6,000 to 10,000 . 16 " " " " " 20,000 to 50,000 . 8 " ten thousand. " " " 50,000 to 100,000 . 4 " " " " " " 200,000 1 " " " A disease is said to be pandemic when it spreads rapidly over a great extent of country, and endemic when it is constantly present in a place. Diseases which may be prevalent in certain localities, i.e., endemic, not infrequently spread over larger areas Public Health, vol. vi, pp. 416, 417. CONTAGION AND INFECTION. 321 of country, overflow their borders, as it were, and become epi- demic or pandemic. Thus cholera, which is endemic in certain districts of India, frequently spreads over adjacent territory, and at times the epidemic wave, as it has been called, rolls over nearly the whole world. Plague, malarial and yellow fevers make similar epidemic excursions into other countries, or sec- tions of country, at a distance from the places where they are endemic. Contagious and infectious diseases possess another peculi- arity in that a certain time is required after the introduction of the poison into the system before the disease manifests itself by its typical symptoms. This is called the "stage of incubation," and varies for different diseases. The following table shows the stage of incubation of a number of such diseases : TABLE XXIX. INCUBATION OF INFECTIOUS DISEASES. Measles, 10 days. Small-pox, 12 " Mumps, 18 " Diphtheria, 3 " Scarlet fever, ....... 3 " Whooping-cough, . . . . . 14 " Typhoid fever, 14 " Typhus fever, 1 to 2 " Chicken-pox, 4 " Erysipelas, 4 " The period during which the infectiveness of the patient lasts also varies. In some cases it probably depends upon the measures taken to prevent the spread of the disease, e.g., disin- fection of the patient and his surroundings. The London Clinical Society has very recently made public a report by one of its committees, which has for several years carefully studied the questions of incubation and the duration of infection. The conclusions reached do not differ essentially from those in the above table, but as they are given somewhat more in detail they are here appended : 21 322 TEXT-BOOK OF HYGIENE. Diphtheria, two to seven days ; oftenest two. Typhoid fever, eight to fourteen days; sometimes twenty- three. Influenza, one to four days ; oftenest three to four. Measles, seven to eighteen days ; oftenest fourteen. Mumps, two to three weeks ; oftenest three weeks. Rubeola, two to three weeks. Scarlet fever, one to seven days ; oftenest two to four. Small-pox, nine to fifteen days ; oftenest twelve. Further investigations were made with regard to the time and duration of the infective period. Diphtheria was found to be infective during the period of incubation, attack, and convalescence. Mumps and rubeola are also infective for three or four days before the onset of the parotiditis and appearance of the rash. The contagiousness of measles speedily disappears, and does not continue in disinfected persons for over three weeks. Typhoid fever is infectious from the time of onset until two weeks after the fever has gone and convalescence set in. As is well known, the contagiousness of scarlet fever varies greatly, but is generally continued a very long time certainly until desquamation ceases, and sometimes as long as eight weeks. QUESTIONS TO CHAPTER XVIII. CONTAGION AND INFECTION. What is the difference between a contagious and an infectious dis- ease ? Give examples of each. What diseases do not belong to either of these classes ? What other names might be given to contagious and infectious diseases ? How do they usually occur ? What are their ex- citing causes ? How may they be prevented ? What is an epidemic ? When may a disease be declared epidemic in a city of 10,000 persons ? When is a disease pandemic ? When en- demic ? May an endemic disease become epidemic or pandemic ? What other peculiarities do contagious and infectious diseases pos- sess ? What diseases have the longest period of incubation ? What ones the shortest ? How does the period of incubation support the germ theory ? What other definite period has each of these diseases ? What is the usual duration of a case of typhoid fever ? Of scarlet fever ? Of measles? Does this support the germ theory ? How long does a typhoid patient remain infective? How long a diphtheria patient? A scarlet- fever patient ? (See chapters on School Hygiene and Quarantine.) Upon what dqes the clanger and period of infectiveness depend ? Are these diseases all likely to confer immunity against future attacks ? Which are most likely to do this ? (323) CHAPTER XIX. HISTORY OF EPIDEMIC DISEASES. AN important part of the knowledge of the sanitarian is that which relates to the history of the great epidemic diseases which have at various periods devastated large areas of the in- habited world. In this chapter the history of these diseases will be briefly traced. Although some of these diseases have nearly or quite ceased, a knowledge of their habits and of the causes that finally led to their extinction is of great value, for the reason that the principles and measures of prevention which were effective in times past are the same which must apply at pres- ent and in the future. Hence, time spent in looking back over the fields traversed and noting victories won will not be wasted. The epidemic diseases which will here claim attention are the Oriental plague, the sweating sickness, small-pox, Asiatic cholera ; typhus, typhoid, scarlet, relapsing, and yellow fevers ; diphtheria, dengue, epidemic influenza, and syphilis. In addi- tion, some information will be given on certain of the diseases of animals transmissible to man. Among these are sheep-pock, actinomycosis, bovine tuberculosis (perlsucht), rabies, anthrax (milzbrand), and glanders. THE ORIENTAL PLAGUE. The Oriental plague, bubonic plague, the black death, or simply the " plague," or great pestilence, overtopping in its fatality all other pestilences, is mentioned by a number of the Greek and Latin medical authors. The first account which clearly refers only to this disease is given by Procopius. Ac- cording to this and other contemporary authors, the disease be- gan to spread in the year 542 from Lower Egypt, passing in one direction along the coast of Northern Africa, and in the other (325) 326 TEXT-BOOK OF HYGIENE. invading Europe by way of Syria and Palestine. In the course of the succeeding years this pandemic reached " the limits of the inhabited earth," in the language of the writers of the day. The disease prevailed about half a century, and produced the greatest devastation wherever it appeared. " Cities were devastated, the country converted into a desert, and the wild beasts found an asylum in the abandoned haunts of man." 1 The plague is an acute infectious disease, which is char- acterized by an affection of the lymphatic system, i.e., inflam- mation and swelling of the external and internal lymphatic glands. Accessory symptoms are petechial spots upon the skin, and haemorrhages from various organs, as the stomach, nose, kidneys, rectum, and uterus. Those attacked suffer in varied degrees of intensity. In some, a fulminant form occurs which carries off the patient within three days ; there is another class of cases in which buboes develop, with accompanying fever and haemorrhages; and, finally, a light form, rarely fatal, in which only the local symptoms are manifested. In the great pan- demic of the plague in the fourteenth century cough and bloody expectorations were very frequent. In the later epidemics haemorrhage from the lungs has been rarely noticed as a symptom. About the middle of the fourteenth century the bubonic plague made a second incursion into Europe from its home in the East. A most graphic description of its ravages is given by Boccaccio in the " Decameron." This author states that in 1359, " between March and July following, according to authentic reckonings, upward of 100,000 souls perished in the city (Florence) ; whereas, before that calamity it was not supposed to contain so many inhabitants." This terrible epidemic was forcibly characterized by its com- mon name, " the black death." Hecker estimates that during its continuance, from 1347 to 1351, 25,000,000 one-fourth of the probable total population of Europe died. In various cities the mortality was in London, 100,000 ; in Paris, 50,000 ; in 1 Warnefried, quoted by Hirsch, Hist-Geographische Pathologic, I, p. 350. THE ORIENTAL PLAGUE. 327 Venice, 100,000 ; in Avignon, 60,000 ; in Marseilles, 16,000, in one month. It was said that in all England scarcely a tenth part of the population escaped death from the disease. The moral effects of this great pandemic of the plague were hardly less deplorable than the physical. Religious fanaticism hold full sway throughout Europe, finding its vent in all manner of excesses. The so-called Brotherhood of the Cross, otherwise known as the Order of Flagellants, which had arisen in the thirteenth century, but had been suppressed by the ecclesiastical authorities, was revived during the black pestilence, and large numbers of these religious enthusiasts roamed through the various countries on their great pilgrimages. Their power in- creased to such a degree that Church and State were forced to combine for their suppression. One consequence of this fanat- ical frenzy was the persecution of the Jews. These were accused of being the cause of every evil that befell mankind, and many were put to death. In the fifteenth and sixteenth centuries the plague was generally diffused throughout Europe, and in the second third of the seventeenth century its final incursion into the Occident took place. The great epidemic in London, so graphically de- scribed by Defoe, 1 occurred in 1665. In the early part of the eighteenth century (1720) the plague visited Marseilles and Toulon ; from 1769 to 1772 it was epidemic in Moldavia, AVal- lachia, Poland, and Southern Russia ; near the close of the last, and in the beginning of the present century, in Transylvania, Wallachia, Southern Russia, and Greece. Very recently, in 1878 and 1879, and in 1885, the plague threatened a new irruption into European territory, being epidemic in the district of Astrachan, on the Caspian Sea. At the date of writing (August, 1894) it is reported epidemic in certain parts of China. Although the bubonic plague has never been observed in America, and has spared Europe almost entirely during the present century, it still persists in certain countries of Asia and Africa, especially in Arabia, Mesopotamia, Persia, and the coast of Tripoli. 1 Journal of the Plague in London. 328 TEXT-BOOK OF HYGIENE. The older authors ascribed the origin of the plague to various real or supposed conditions. Comets, conjunctions of the planets, " God's just punishment for our sins," and similar causes were advanced to account for the outbreaks. Most of the writers of the post-medieval and modern epochs ascribed the disease to meteorological conditions. Observing the fact that the plague never advanced into the torrid zone, and that an epidemic generally ended with the advent of hot weather, a high tempera- ture was believed to be incompatible with the existence of an epidemic, and a cold or temperate climate was considered neces- sary to an outbreak of the disease. The exceptions to the rule are so numerous, however, that the theory of the climatic or meteorological origin of the plague failed of support. The theory which ascribed the origin of the epidemics to the influence of certain hot and dry winds or a high humidity is also insufficient. Certain geological formations have been supposed to furnish favorable conditions for the development of the disease. Facts show, however, that the disease has prevailed epidemically and endemically in various parts of the earth, and of the most diverse geological character. A certain elevation above sea-level has been held to confer immunity, but recent observations in India show that this belief is unfounded, even places at an elevation of 10,000 feet above sea-level giving no security against attack. There is, however, one point upon which nearly all writers who mention the fact at all agree. This is that hid hygienic conditions are always present where plague prevails. Nearly all observers who have left their impressions on record mention the accumulation of filth in the houses and streets, deficient removal of excrementitious and other sewage matters, crowding and im- perfect ventilation of dwellings as causes favoring the develop- ment and spread of the pestilence. All point out the necessity of the removal of these evils as the most important prophylactic measure to be adopted, and all of them call attention to the fact that those classes of the population most exposed to these unfa- vorable influences suffer most from the violence of the epidemic. THE ORIENTAL PLAGUE. 329 The later reports of the epidemics in Persia, India, Mesopo- tamia, and Russia agree in asserting that nothing seems to have promoted the epidemic and endemic prevalence of the plague so much as the material wretchedness of the inhabitants of those countries. In a collection of papers on the plague, printed by a British Parliamentary Commission in 1879, occur these state- ments : " The filth is everywhere," says Mr. Rennie, one of the reporters, " in their villages, their houses, and their persons. Their dwellings are generally low and ill-ventilated, except through their bad construction ; and the advantage of the natives in other parts of India, of living in the open air, is lost to the villagers of Ghurwal, from the necessity of their crowding together for mutual warmth and shelter against the inclemency of the weather"." Dr. Dickson, reporting on the plague in Irak Arabi in 1876, says: " The most palpable and evident of all the causes which predispose an individual to an attack of plague during an epidemic outbreak is poverty. No other malady shows the influence of this factor in so striking a degree ; so much so, indeed, that Dr. Cabiadis styles the plague miserice mortis. In his experience (1876-77, in Bagdad) he found that the poor were seldom spared, the wealthy hardly ever attacked." The manner of the transmission of the plague is generally by prolonged inhalation of an infected atmosphere. Hence, it may be termed an infectious disease, although it is not improbable that it may be communicated by direct contact botli of persons and of fomites. It is probably due to a micro-organism, although no demonstration of the latter has been furnished up to the present time. These considerations indicate the measures of prevention to be adopted. They consist of a rigid quarantine of persons and fomites, prompt and complete isolation of infected individuals and localities, and destruction (by fire) or thorough disinfection by steam or sulphurous-acid gas of all materials capable of con- veying the virus of the disease. 1 Hirscb, op. clt., p. 370. 330 TEXT-BOOK OF HYGIENE. THE SWEATING SICKNESS. This name concisely characterizes an epidemic disease which for the first time appeared in the city of London and other parts of England in the autumn of 1485. According to Lord Bacon, 1 the disease began about the 21st of September and lasted until near the end of October. It broke out a second time in the summer of 1507; a third time in July, 1518, spread- ing in the course of six months throughout England. In May, 1529, the disease made its appearance again in the latter country, spreading thence over a great part of the continent of Europe. Another very malignant epidemic broke out in the spring of 1541, lasting through the summer, and limited in its ravages to England. With this last outbreak, in 1551, this disease disappeared entirely in England and has not re-appeared there up to the present day. In the beginning of the eighteenth century, how- ever, a disease very similar in its symptoms and course broke out in Picardy and other districts of Northern France, being confined for a number of years to this section of the country. Toward the end of the century it spread to the south of France, and since that time has appeared epidemically at intervals, 195 dis- tinct outbreaks having been observed in the course of 168 years, from 1718 to 1887. The disease has frequently appeared in Italy since 1755, and in various parts of Germany since 1801. In Belgium it has been observed at a few places within the present century. The disease appeared suddenly, often at night-time. The patient was attacked with palpitation of the heart, dyspnoea, great anxiety and oppression, and profuse perspiration. A miliary eruption often appeared on the skin. In favorable cases these symptoms diminished in the course of one or two days, the urinary secretion, which had been suppressed, was restored, and the perspiration became gradually less free. Recovery ensued in from one to two weeks. In grave cases there were, in the 1 History of Henry VII. SMALL-POX. 331 beginning of the attack, violent headache, delirium, convulsions, followed by a comatose condition, from which the patients rarely recovered. This disease is undoubtedly of a miasmatic, infectious nature, as proved by its rapid spread and limitation to certain localities. It appears most frequently in the spring and summer, and is nearly always observed in marshy or damp localities. Its spread is favored by a high temperature and humidity. There is no apparent connection between the outbreaks of the sweating sickness and overcrowding or other insanitary conditions; in fact, it is stated by numerous observers, both old and recent, that children, the aged, and generally the' poorer classes were remark- ably exempt from the disease. The recent epidemic in France, in 1887, was investigated by Dr. Brouardel, Chantemesse, and other epidemiologists, but no trustworthy conclusions as to the nature of the disease have yet been reached. Since the first appearance of Asiatic cholera in France, in 1832, an apparently intimate connection has been observed between the occurrence of that disease and outbreaks of sweating sickness. A disease strongly resembling the sweating sickness has also been observed in India in districts contiguous to places where cholera was at the time epidemic. 1 SMALL-POX. The earliest details concerning small-pox are derived from certain Chinese records, according to which it appears that this disease was known in China upward of 2000 years ago. It was also known at a very early period in India. It is believed to have been introduced into Europe in the second century by a Roman army returning from Asia. It is believed that the Em- peror Marcus Aurelius died of small-pox, which prevailed in his army at the time of his death. The first distinct references to small-pox in medical literature occur in the writings of Galen, in the second century. Rhazes, 1 Murray, Madras Quart. Med. Journ., 1840-41. Quoted in Hirsch, loc. cit., p. 83. 332 TEXT-BOOK OF HYGIENE. in the ninth century, wrote upon the disease, describing it very accurately. The almost universal susceptibility to small-pox caused wide-spread devastation wherever it appeared previous to the introduction of vaccination. The statement is made that in England, in the last century, about one person in every three was badly pock-marked. The mortality from the disease was exceedingly great, being, in the latter half of the eighteenth century, about 3000 per million of inhabitants annually. In India the mortality from small-pox has been exceedingly great within the last twenty years. From 1866 to 1869, 140,000 persons died in the Presidencies of Bombay and Calcutta, having a population of about 40,000,000. Several years later, from 1873 to 1876, 700,000 died from this disease. China, Japan, Cochin China, the islands of the China Sea, and Corea are frequently ravaged by small-pox. In the latter country nearly all the inhabitants are said to bear evidence of an attack of the disease. The Samoyedes, Ostiaks, and other natives of Eastern Siberia have frequently suffered from devastating epidemics. In Kamt- chatka the disease was introduced in 1767, and produced frightful ravages. Many villages were completely depopulated. In Mexico small-pox was introduced by the Spaniards in 1520. In a short time it carried off over 3,500.000 of the natives. In the Marquesas Islands one-fourth of the inhabitants have fallen victims to the disease since 1863. It was first introduced into the Sandwich Islands in 1853, and carried off 8 per cent, of the natives. Australia, Tasmania, New Zealand, and the Fejee Archi- pelago remain exempt to the present day from small-pox. It has several times been carried to Australia by vessels, but has always been promptly checked by the vigilance of the authorities. On the Western Hemisphere small-pox was unknown before the arrival of the European conquerors. It has been spread by the whites or imported African slaves to nearly all the Indian SMALL-POX. 333 tribes of both continents. When it attacks large communities unprotected by previous outbreaks of the* disease, or by inocula- tion or vaccination, its ravages are frightful. The mortality of unmodified small-pox is usually between 30 and 40 per cent. Small-pox is a highly contagious and infectious disease. It is produced by actual contact, by inoculation, and by inhaling an atmosphere charged with the poison. In order to cause an outbreak two factors are necessary : first, a number of individuals susceptible to this disease, and, second, the introduction into the body, in some manner, of the virus upon which it depends. Small-pox is spread from (1) persons sick with the disease; (2) others, not themselves sick or susceptible, but coming in contact with the poison ; (3) fomites (cotton, wool, etc.), and (4) the bodies of persons dead with small-pox. It is also probable that the air in the immediate vicinity of a person sick with small- pox becomes charged with the poison and able to convey the disease. It is at present impossible to fix the distance to which this infectiousness of the air extends, but it does not ordinarily reach beyond the room in which the patient is confined. It is a fact of common observation that the darker races are more commonly attacked, and the disease is likewise more fatal among them. The mortality among negroes is much larger than among other races. It is a current belief that small-pox is only contagious after the development of the pustules. This is a serious error. It is probably contagious in all stages of the disease ; certainly as early as the first appearance of the eruption, and probably even in the stage of preliminary fever. One attack of small-pox usually confers immunity from the disease for life. This rule has its exceptions, however, which, if not numerous, are yet not infrequent. The author has seen a case in which the patient suffered from a third attack of the disease. The popular belief, that persons suffering from any acute or chronic disease are less liable to be attacked by small-pox 334 TEXT-BOOK OF HYGIENE. than those at the time in good health, is erroneous. On the contrary, the subjects of chronic disease, such as consumption or dyspepsia, are much more liable to succumb to an attack of small-pox than persons previously in good health. It is true, however, that individuals suffering from some other acute infectious disease, like scarlet fever, measles, typhoid fever, etc., are generally, though not absolutely, exempt from an attack of small-pox during the time they are sick with such disease. But if they are exposed, after recovery, to the small- pox infection, their liability to an attack is as great as in those who have not passed through a similar disease. A number of cases have been reported by Curschmann, 1 in which infection by small-pox took place on the day in which convalescence from typhoid fever was established. The author has reported a case 2 in which the patient passed through an attack of erysipelas during the incubative stage of small-pox. From all the evidence attainable, the incubative stage was not prolonged by the intercurrent erysipelas. Epidemics of small-pox usually begin in the autumn or winter, and lessen in violence as warmer weather approaches. The spread of the disease is slow at first, increasing in rapidity as the foci of infection multiply. When the poison is imported into a community late in the spring or during the summer, the increase in the number of cases is exceedingly gradual until colder weather sets in. If it is introduced during the winter, the disease spreads much more rapidly, but decreases, and sometimes almost disappears, during the summer. On the return of cold weather, however, the epi- demic starts out with a new lease of activity and presents great difficulties to its restriction. A number of observers, among whom are Coze and Feltz, Lugenbuhl, Weigert, Strauss, Garre, and Wolff, claim to have discovered specific organisms in the contents of variolous pustules, in the blood of patients with the disease, and in vaccine lymph. 1 Ziemssen's Cyclopaedia, vol. ii. ' Medical News, July 7, 1883. SMALL-POX. Expert bacteriologists are, however, not willing to accept the evidence hitherto furnished as conclusive. Inoculation. The prevention or restriction of such a uni- versal and fatal pestilence as small-pox is a matter of the deepest importance. The first attempt to limit its fatality dates from the end of the seventeenth century. It became generally known in Europe, about the year 1700, that the intentional inoculation of variolous matter into healthy individuals induced an attack of the disease, which generally ran through its various stages with less virulence than when the disease was contracted in the usual manner. In 1716 and 1717 two papers were published in the " Transactions of the Royal Society of England" giving an ac- count of the process of inoculation. The attention of the public was especially directed to the matter, however, by the famous letter of Lady Mary Wortley Montagu, dated April 1,1717. This letter is as follows 1 : "Apropos of distempers, I am going to tell you a thing that will make you wish yourself here. The small- pox, so fatal and so general amongst us, is here entirely harm- less by the invention of ingrafting, which is the term they give it. There is a set of old women who make it their business to perform the operation every autumn, in the month of September, when the great heat is abated. People send to one another to know if any of their family has a mind to have the small-pox ; they make parties for this purpose, and when they are met commonly fifteen or sixteen together the old woman comes with a nut-shell full of the matter of the best sort of small-pox, and asks what veins you please to have opened. She immediately rips open that you offer to her with a large needle which gives you no more pain than a common scratch and puts into the vein as much matter as can lie upon the head of her needle, and after that binds up the little wound with a hollow bit of shell ; and in this manner opens four or five veins. The Grecians have commonly the superstition of opening one in the middle of the forehead, one in each arm, and one on the breast, to make 1 The letter is addressed to Mrs. S. C. (Sarah Chiswell). 336 TEXT-BOOK OF HYGIENE. the sign of the cross ; but this has a very ill effect, all these wounds leaving little scars, and is not done by those that are not superstitious, who choose to have them in the leg or that part of the arm that is concealed. The children or young pa- tients play together all the rest of the day, and are in perfect health until the eighth. Then the fever begins to seize them, and they keep their beds two days, very seldom three. They have rarely above twenty or thirty in their faces, which never mark ; and in eight days' time they are as well as before their illness. Where they are wounded there remain running sores during the distemper, which I don't doubt is a great relief to it. Every year thousands undergo this operation ; and the French ambas- sador says pleasantly : ' They take the small-pox here by way of diversion, as they take the waters in other countries.' There is no example of any one that has died in it, and you may believe that I am well satisfied of the safety of the experiment, since I intend to try it on my dear little son. "I am patriot enough to take pains to bring this useful invention into fashion in England; and I should not fail to write to some of our doctors very particularly about it, if I knew any of them that I thought had virtue enough to destroy such a considerable branch of their revenue for the gtfod of mankind. But that distemper is too beneficial to them not to expose to all their resentment the hardy wight that should undertake to put an end to it. Perhaps, if I live to return, I may, however, have courage to war with them." Soon after the date of this letter the writer's son was inoculated in Turkey, and four years later her daughter also, being the first subject inoculated in England. The practice soon became popular, but several fatal cases among prominent families brought it into disrepute, and for about twenty years very few inoculations were made in England. It was revived about the middle of the century by the founding of a small-pox and inoculation hospital in London. This continued in opera- tion until 1822. The records of this institution showed that only SMALL-POX. 337 three in a thousand died of the disease thus communicated. The practice has now fallen into desuetude, being superseded by vac- cination and prohibited by law in England. Inoculation was introduced into this country in 1721 by Dr. Zabdiel Boylston, of Boston, who had his attention directed to the practice by Cotton Mather, the eminent divine. 1 During 1721 and 1722, 286 persons were inoculated by Boylston and others in Massachusetts, and 6 died. These fatal results ren- dered the practice unpopular, and at one time the inoculation hospital in Boston was closed by order of the Legislature. Toward the end of the century an inoculating hospital was again opened in that city. Early in the eighteenth century inoculation was extensively practiced by Dr. Adam Thomson, of Maryland, who was instru- mental in spreading a knowledge of the practice throughout the Middle States. 2 In China and India, and perhaps other eastern countries, inoculation was practiced at a very early period. The inoculation of variolous matter, although it mitigated to a very great degree the attack of small-pox following, had one very serious objection, aside from the small death-rate which was a direct consequence of it. This was the fact that inocula- tion always produced small-pox, and thus assisted in propagating the disease; for, however mild the induced disease might be, the inoculated individual was liable to communicate small-pox to others in the most virulent form. Hence, nothing short of uni- versal inoculation, which was manifestly impracticable, would succeed in reducing the danger from the disease. Vaccination. It had been noticed at various times that a pustular disease which sometimes appears on the udders of cows, called cow-pox, had not infrequently been transmitted to the hands of the dairy-maids and others having much to do with 'Dr. John R. Quinan (M<1. Med. Journ., June 23 and 30, 1883) believes the claim of Dr. Boylston to be the first American inoculator open to question. The evidence presented is, how- ever, insufficient to discredit the claim of the Koston physician. 1 See Quinan, loc. cil., p. 114. 22 338 TEXT-BOOK OF HYGIENE. cows. In course of time it was also noticed that persons who had been thus attacked never suffered from small-pox. This protective power of cow-pox was known as early as 1713, and in 1774 Benjamin Jesty, a Gloucestershire farmer, performed vaccination for the first time on record, inoculating his wife and two sons with cow-pox matter as a protection against small-pox. It is stated that when it became known that Jesty had vaccinated his wife and sons, "his friends and neighbors, who had hitherto looked upon him with respect, on account of his superior intelligence and honorable character, began to regard him as an inhuman brute, who could dare to practice experi- ments upon his family, the sequel of which would be, as they thought, their metamorphosis into horned beasts. Consequently the worthy farmer was hooted at, reviled, and pelted whenever he attended the markets in his neighborhood." 1 In 1791 a school-teacher in Holstein also inoculated three boys with the matter of cow-pox, but nothing is known of the subsequent history of these cases. Although the above facts are clearly established, it is to Edward Jenner, a modest country doctor of Berkeley, in the county of Gloucester, England, that the merit of demonstrat- ing the protective power of cow-pox against small-pox, and of diffusing a knowledge of this fact, is due. Jenner had his atten- tion directed to the asserted protection conferred by cow-pox during the period of his apprenticeship. After a residence in London as a pupil of John Hunter, he returned to the country to practice his profession. About the year 1776 he began studying the question, and gathering evidence of the protection afforded against small-pox by the accidental inoculation of cow- pox virus. For twenty years he studied the subject, patiently awaiting an opportunity to put his belief to the test of experi- ment. On the 14th of May, 1796, he made his first vaccination on a boy named James Phipps. Six weeks later he inoculated this boy with variolous matter, but without success, no small- 1 London Lancet, September 13, 1862. SMALL-POX. 339 pox resulting. Two years later he published his pamphlet, .MI titled " An Inquiry into the Causes and Effects of the Variola Vaccm.se, etc.," in which he detailed his observations and experi- ments. This publication produced a great sensation in the medical world, and, although much opposition was at first manifested toward his views, he soon gained many adherents. * Vaccination, as the operation for the inoculation of cow-pox virus is termed, was rapidly introduced into all civilized countries, and soon demonstrated its good effects by greatly restricting the prevalence of small-pox. It is generally believed that the first one to practice vaccination in this country was Dr. Benjamin Waterhouse, of Boston, in the summer of 1800; but Dr. John R. Quinan has recently shown l that vaccination was introduced into Maryland, by Dr. John Crawford and Dr. James Smith, at least as early as the date generally assigned for its introduction into Massachusetts. It was believed by Dr. Jenner, and was afterward conclu- sively shown by a number of distinguished experimenters, that vaccinia, as the disease produced by cow-pox inoculation was called, was merely a modification of small-pox as it existed in the cow. Small-pox virus, when inoculated upon the cow, produced cow-pox; but the latter, re-inoculated upon man, produced cow-pox (vaccinia), and not small-pox. Sheep-pock and horse-pock, or " grease," are probably merely modifications of the disease produced by inoculating small-pox into those animals. When cow-pox virus is successfully inoculated into the human system that is, when a person is successfully vaccinated the following local and general symptoms are observed : In the case of a primary vaccination, i.e., where the individual has not been previously vaccinated or attacked by small-pox, the point where the vaccination is made shows no particular change for the first two days. If the vaccination is successful, a small, reddish papule appears by the third day, 1 Quinan, loc. cit., pp. 118, 131. 340 TEXT-BOOK OF HYGIENE. which, by the fifth or sixth day, has become a distinct vesicle of a bluish-white color, with a raised edge and a peculiar, central, cup-like depression called the umbilication. By the eighth day this vesicle has become plump, round, and pearl-colored, the central umbilication being still more marked. At this time a red, inflamed circle, called the areola, appears, surrounding the vesicle and extending usually in a radius of from ^ to 2 inches* when fully developed. This inflammatory ring is usually pretty firm, and there is more or less general fever and often enlarge- ment and tenderness of the axillary glands. After the tenth day the areola begins to fade, and the contents of the vesicle dry into a hard, brownish crust or scab, which falls off between the twentieth and twenty-fourth days, leaving a punctated scar, which gradually becomes white. When the vaccinia has passed through all of these stages, especially if the vesicle filled with pearly lymph, and the areola have been well developed, the vaccination may be considered a success, and the individual protected against small-pox for a number of years, if not for life. Recently the doctrine has been strongly advocated that vaccination is not absolutely protective until a subsequent inoculation of vaccine fails to " take." According to this view, vaccination should be repeated until it fails any longer to exhibit any local reaction. When this has .been attained the individual may be considered absolutely protected for life. Theoretically, this view has much in its favor, but there is, as yet, not sufficient evidence to establish it as a law. It may be stated as an established fact that vaccination, although carefully performed and successful, does not confer absolute immunity from small-pox for life. The protective power seems to wear out after a time and the individual then again becomes susceptible to small-pox. An attack of small- pox in a vaccinated individual is, however, nearly always much milder than where there had been no vaccination. There is no fact in the entire range of medicine better established than this : SMALL-POX. 341 that small-pox in vaccinated persons is a much less dangerous disease than typhoid fever, while in unvaccinated cases the mortality ranges from 30 to 40 per cent. An approximate guide to the beneficent influence of vaccination upon the mortality from small-pox is furnished by a table in Seaton's report on vaccination. Before the introduction of vaccination the mortality from small-pox, per million of inhabitants of Eng- land, was nearly 3000 per year. After the introduction of vac- cination the mortality was reduced to 310 per million per year. The most remarkable and convincing statistical evidence on the question is given by Drs. Seaton and Buchanan, of England. During the small-pox epidemic in London, in 1863, they examined over 50,000 school-children, and found among every thousand without evidence of vaccination 360 with scars of small-pox, while of every thousand presenting some evidence of vaccination only 1.78 had any such traces of small-pox to exhibit. 1 The reliability of general mortality statistics may be called in question in some cases, with justice ; but the signifi- cance of these figures cannot be evaded. The upper and outer surface of the arm is usually chosen as the point where the virus is inserted, although any part of the body which can be protected against friction, or other mechanical irritation, may be selected. The method varies slightly in the hands of different vaccinators. The two methods most frequently in use are scarification and erasion. The former method has the indorsement of Mr. Seaton, the high English authority. The method of erasion scraping off the epidermis until the papillary layer of the skin is laid bare is now most frequently used in this country. The best instrument to use is a clean thumb-lancet ; in default of this, an ordinary sewing-needle answers well. Where animal vaccine is used, the ivory slip or sharpened quill may also be used with satis- faction to make the scarification or erasion. Whatever instru- ment is used, it should always be kept perfectly clean. 1 Seaton, " Vaccination," in Reynolds's System of Medicine, vol. i, p. 291. Second edition. 342 TEXT-BOOK OF HYGIENE. A point of vital importance is that which relates to the proper age at which children should be vaccinated. Ordinarily, vaccination should be performed within the first six months of life. In time of danger from a threatened, or in the presence of an actual, epidemic, infants may be vaccinated when only 1 day old. In order to secure permanent protection against small-pox, revaccination should be performed after a certain interval. Some place the period at which this second vaccination should be done at five years, while others allow a longer interval seven, eight, or ten years. The law of Prussia is that every child that has not already had small-pox must be vaccinated within the first year of its life, and every pupil in a public or private institution is to be revaccinated during the year in which his or her twelfth birthday occurs. This law was passed in 1874. Prior to this time the mortality from small-pox was 15 to 20 per 100,000 of the population. Since the law was enacted the small-pox mortality has varied from 0.3 to 3.6 per 100,000. Not a single death from small-pox occurred in the German army between 1874 and 1882. 1 A revaccination, even if successful, seldom passes through all the typical stages of a primary vaccination. The vesicle rarely becomes so full and plump, and is more frequently flat and irregular in outline. Swelling of the axillary glands and other complications also seem to be more frequent than in cases where the vaccination is done for the first time. The question whether the lymph direct from the cow or humanized lymph is the more efficient has caused much dis- cussion. The objections urged against the use of humanized virus are : first, that its protective power has become diminished by transmission through many generations ; second, that it is liable to transmit other diseases, such as syphilis, tuberculosis, scrofula, etc. ; third, that it is frequently difficult to obtain in 1 Frolich, Militar-Medicin, p. 461. SMALL-POX. 343 sufficient quantities in an emergency, such as an actual or threatened epidemic. The first objection is disproved by the testimony of many of the most distinguished medical men in Europe and this country. Humanized vaccine virus, when properly inoculated, seems to be as completely protective against small-pox as that taken direct from the animal. Among its advantages are, that it " takes " more readily and runs through its stages of develop- ment in a shorter time, and that it will retain its active proper- ties for a greater length of time than animal virus. The physician can usually control the source whence he obtains it. He can watch over the subject that furnishes it and reject that which is suspicious. With humanized lymph collected by the physician himself there can be no doubt as to its purity or age ; with animal lymph furnished by the cultivators of that article there can be no certainty about either of these important points. That syphilis has been inoculated with humanized virus can no longer be open to doubt. The recent experiment of Dr. Cory, of England, has settled this question definitely. With care, however, this sad accident can easily be avoided, and the fact that syphilis has been so rarely transmitted by vaccination is sufficient evidence that the danger of such infection is not very great. The most serious objection against the exclusive use of humanized lymph is, that in grave emergencies, such as a rapidly-spreading epidemic of small-pox, it is difficult to obtain a sufficient supply of the lymph. Humanized virus is inoculated, either in the fresh state, i.e., the lymph is taken from the vesicle on the seventh day and inoculated directly into the arms of other individuals, or else the vesicle is allowed to dry into a crust, with which a thin paste is made by moistening with water at the time of vaccination. The readiest way of using the crust is to crush a small fragment between two small squares of glass, then moistening it with a drop of warm (not hot) water, and smearing it on the spot 344 TEXT-BOOK OF HYGIENE. where the vaccination is to be made. With the lancet a number of cross-scarifications are then made, and the virus well rubbed in. Only so much of the crust should be moistened as will be used at the time. Particular care must be taken not to use saliva for moistening the crust. Aside from being unclean, there is danger of producing blood-poisoning by inoculating certain of the oral secretions. 1 Animal virus is obtained by inoculating a calf or heifer with virus, either derived from a case of small-pox, from another case of cow-pox, or by re-inoculating humanized vaccine virus into the animal. The vesicles are opened on the seventh day, and ivory points or the ends of quills coated with the lymph and dried with a gentle heat. In vaccinating with animal virus, the quill or ivory point is first moistened with a drop of water to soften the adhering lymph ; the scarification or abrasion of the skin is then made with the lancet, and the virus rubbed well into the scarified spot. In using animal virus the successive stages of development are usually one or two days later than when humanized virus is used. In the former case the areola is rarely developed before the ninth day. Certain complications are likely to occur in the course of the vaccinia, of which the student should be aware. When the areola appears there is usually more or less fever. Sometimes the constitutional manifestations are de- cidedly marked, fever of a high grade being not uncommon. In addition to the glandular enlargement arid tenderness, an outbreak of roseola sometimes comes on about the ninth or tenth day. This eruption may be mistaken for scarlet fever, but if it is remembered that two infectious diseases rarely co- exist in one individual during their full development this error will be avoided. Erysipelas involving the entire arm is sometimes observed 1 See Stern berg and Magnin, Bacteria, p. 355. Second edition. SMALL-POX. 345 as a complication of vaccination. This, in nearly every case, depends upon some depravement of the patient's constitution, innutrition, bad sanitary surroundings, or, perhaps, more fre- quently, chronic alcoholism. Individuals who are habitually intemperate in the indulgence of alcoholic liquors are espe- cially unfavorable subjects for vaccination. The results are, fortunately, rarely serious to the patient. Another inconvenient complication of vaccination is the formation of a deep, ill-looking, sloughing ulcer at the vacci- nated point. This has been, in the author's experience, a much more frequent concomitant when animal virus has been used than when humanized virus was resorted to. It should be borne in mind that a very sore arm, especially if followed by the formation of an ulcer or gangrenous sore, may not be protective against small-pox. Such a patient should not be considered properly vaccinated, and must be revaccinated as soon as he recovers, or immediately if there is any danger of small-pox infection. Children with eczematous eruptions, however, localized upon any portion of the body, should not be vaccinated until the eruption is first cured, except in times of danger from small-pox. The eczema will be almost certainly rendered worse in consequence of the general hyperaemia accompanying the febrile reaction, and the physician who performs the vaccination will be blamed for causing the skin disease. The author has placed on record 1 two cases of general psoriasis following vaccination, and other cases have been since reported. Urticaria and exudative erythema have also been repeatedly observed. As before stated, syphilis may be communicated to the vaccinee by vaccine virus obtained from a syphilitic subject, but this accident is infrequent. There can be little doubt that some of the cases reported as " vaccinal syphilis " are cases of tardy hereditary syphilis, lighted up by the general systemic disturb- ance following vaccination. 1 Journal Cutaneous and Venous Diseases, vol. i, No. 1, p. 11. 346 TEXT-BOOK OF HYGIENE. Next in importance to vaccination in the prophylaxis of small-pox is prompt isolation of the sick. No one but the medical and other attendants of the sick should he allowed to come in contact with them. All attendants and other persons exposed to the infection should, of course, be promptly vacci- nated, unless this has been successfully done within the previous year or two. Disinfection of all discharges from the patient and of the room and its contents, after the patient has recovered or died, must be practiced. The best disinfectants in small-pox are bichloride of mercury, free chlorine, and sulphurous acid. When it is learned that a person has small-pox, if he is not removed to a special hospital, a room should be prepared for his occupancy. The carpets should be taken up and the floor kept clean. Window-curtains and unnecessary furniture and drapery should be removed from the room. After recovery of the patient the bed-clothing must be thoroughly disinfected with steam or sulphurous acid, or destroyed by fire. The individual himself should not be allowed to mingle with healthy persons until all danger of infection is passed and the surface of his body has been thoroughly disinfected! At a recent conference of sanitary officials in the city of Chicago (May, 1894) the following propositions were adopted. They represent the most advanced conclusions of competent authority upon the most practical means of limiting the spread of small-pox : " 1. The city should be divided into districts containing not more than 10,000 people. " 2. Each district should be placed under the supervision of a competent medical inspector with necessary assistants to (a) make a house-to-house inspection ; (ft) to successfully vacci- nate, within the shortest possible time, all persons who have not been vaccinated during the outbreak, and that the first vaccina- tion be within seven days ; (c) to properly disinfect all houses and their contents where small-pox occurs. " 3. Necessary means and appliances for efficient disirifec- ASIATIC CHOLERA. 347 tion of materials, premises, etc., should be provided as the exigencies of each district may require. " 4. Each case of small-pox should be immediately removed to a suitably constructed and properly equipped and officered isolation hospital. " 5. Except in extreme cold weather, hospital tents, as prescribed in the United States Army Regulations, floored and warmed, are preferable to the average hospital or private dwell- ing, and increase the chances of recovery of the patients. Cases of small-pox necessarily detained in their own homes should, with their attendants, be rigidly isolated during the period of danger, and physicians visiting such patients professionally shall be sub- ject to such regulations as may be prescribed by the local health officer. " 6. Persons exposed to small-pox contagion should be immediately vaccinated or revaccinated, and kept under observa- tion for not less than fourteen days from time of last exposure. " 7. It is the sense of this conference that where such measures are all enforced it will not be necessary for neighbor- ing cities and states to exclude all persons who come from such city who are not protected against small-pox by vaccination, and to require disinfection of all baggage and merchandise capable of conveying small-pox infection." ASIATIC CHOLERA. A disease which causes the death of three-fourths of a million of human beings where it is endemic within the space of five years, and which makes periodical excursions, spreading over nearly the entire inhabited globe with destructive violence, must surely command the interested attention of every intelli- gent person. Asiatic cholera is endemic in India, where it probably originated centuries ago. Some authors claim to have found satisfactory evidence of its existence in the writings of the classical authors of India and Greece at a period as early as the second century of the Christian era. The evidence is, however, not beyond question. In the sixteenth and seventeenth cen- 348 TEXT-BOOK OF HYGIENE. turies European travelers in the East gave pretty exact accounts of the disease. One of the most definite of these was given by Gaspar Correa, an officer in Vasco da Gama's expedition to Calicut. He states that Zamorin, the chief of Calicut, lost 20,000 of his troops by the disease. A still more definite and the first trustworthy account is that of Sonnerat, a French trav- eler. He describes a pestilence having all the characters now recognized as belonging to Asiatic cholera, which prevailed in the neighborhood of Pondicherry and the Coromandel coast in 1768 and 1769, and which carried off 60,000 of those attacked by it within a year. Dr. Macpherson, in his " History of Cholera," gives numerous references which indisputably establish the en- demic existence of the disease in India anterior to the present century. Being endemically prevalent over a greater or less area of India for many years, cholera finally, in 1817, crossed the boundaries of that country, and, advancing in a southeasterly direction, invaded Ceylon and the Sunda Islands in 1818. In a westerly direction the disease was carried to the islands of Mauritius and Reunion, and reached the African coast in 1820. During* this year it also traveled northeasterly, devastating the Chinese Empire for the two following years, reaching Nagasaki, in Japan, in 1822. In 1821 the disease spread from India in a westerly direc- tion, extending along the east coast of Arabia to the border of Mesopotamia and Persia. In the spring of 1822 it began with renewed violence, following the river Tigris to Kurdistan, and, extending farther in a westerly direction, reached the Mediter- ranean coast of Syria. In the following year, 1823, it extended from Persia into Asiatic Russia, reaching Astrachan on the European border in September, but dying out nearly every- where beyond the borders of India during the ensuing winter. In 1826 cholera again advanced from India, reaching Orenburg in Russia in 1829, and in the following winter appeared in St. Petersburg. Extending to the north and south, ASIATIC CHOLERA. 349 it invaded Finland and Poland the same year. From Persia the disease spread* to Egypt and Palestine in 183031. From Russia the pestilence invaded Germany in 1831, passing thence in 1832 into France, the British Isles, Belgium, the Netherlands, Norway, and Sweden. In the latter year cholera crossed the Atlantic Ocean for the first time, being car- ried to Canada by emigrants from Ireland, and spreading thence to the United States by way of Detroit. In the same year it was imported into New York by emigrants, and rapidly spread along the Atlantic coast. During the winter of 1832 it appeared at New Orleans, and passed thence up the Mississippi Valley. Extending into the Indian country, causing sad havoc among the aborigines, it advanced westward until its further progress was stayed by the shores of the Pacific Ocean. In 1834 it re-appeared on the east coast of the United States, but did not gain much headway, and in the following year New Orleans was again invaded by way of Cuba. It was imported into Mexico in 1833. In 1835 it appeared for the first time in South America, being restricted, however, to a mild epidemic on the Guiana coast. While the pestilence was advancing in the Western Hemi- sphere, it also spread throughout Southern Europe, invading, in turn, Portugal, Spain, and Italy. Extending in an easterly direction from India, the disease reached China and Japan in 1830-31 ; westwardly, Africa was invaded in 1834, and ravaged by the epidemic during the following three years. This second extensive outbreak of cholera ended in 1837, disappearing at all points beyond the borders of India. In 1846 the disease again advanced beyond its natural confines, reaching Europe, by way of Turkey, in 1848. In the autumn of this year it also appeared in Great Britain, Belgium, the Netherlands, Sweden, and the United States, entering by way of New York and New Orleans. In the succeeding two years the entire extent of country east of the Rocky Mountains was in- vaded. During 1851 and 1852 the disease was frequently im- 350 TEXT-BOOK OF HYGIENE. ported by emigrants, who were annually arriving in great num- bers from the various infected countries of Europe. In 1853 and 1854, cholera again prevailed extensively in this country, being, however, traceable to renewed importation of infected material from abroad. In the following two years it also broke out in numerous South American States, where it prevailed at intervals until 1863. Hardly had this third great pandemic come to an end before the disease again advanced from the Ganges, spreading throughout India, and extending to China, Japan, and the East India Archipelago during the years 1863 to 1865. In the latter year it reached Europe by way of Malta and Marseilles. It rapidly spread over the Continent, and in 1866 was imported into this country by way of Halifax, New York, and New Orleans. This epidemic prevailed extensively in the Western States, but produced only slight ravages on the Atlantic coast, being kept in check by appropriate sanitary measures. In the same year (1866) the disease was also carried to South America, and in- vaded, for the first time, the States bordering on the Rio de la Plata and the Pacific coast of the Continent. While the epidemic was thus advancing westward from its home in India, it was at the same time spreading northwardly over the entire western part of Asia, and in a southeasterly direction over Northern Africa. In the latter continent it pre- vailed from 1865 to 1869. Cholera never entirely disappeared in Russia during the latter half of the sixth decade, and in 1870 it again broke out with violence, carrying off a quarter of a million of the inhabi- tants before dying out in 1873. It spread from Russia into Germany and France, and was imported, in 1873, into this country, entering by way of New Orleans and extending up the Mississippi Valley. None of the Atlantic-coast cities suf- fered from the epidemic in 1873, and since that year the United States have been entirely free from the disease, with the excep- tion of a few imported cases in New York Harbor in 1887. ASIATIC CHOLERA. 351 In June, 1883, a new epidemic of cholera broke out in Egypt, where it raged with great violence. The disease first appeared in Damietta, near the outlet of the Suez Canal. It was unquestionably imported from India, probably Bombay, where it prevailed as early as the month of May. At the time of the outbreak in Damietta that city was overcrowded with people who had come to attend a great religious fair and festival. It has been proven that pilgrims from Bombay were among the attendants at this fair. The epidemic came to an end in Egypt in the autumn of 1883. In the same year (1883) a small out- break occurred in Marseilles, but intelligence of it was carefully suppressed by the authorities. The disease does not seem to have spread from this centre, but in June of the following year cholera broke out in Toulon, having probably been imported in a transport ship returning from Tonquin. This outbreak was very violent and rapidly spread throughout Southern France, Italy, and Spain. After apparently dying out during the winter, it re-appeared in the spring of 1885 with renewed violence. The total number of cases in Spain alone in the latter year was over one-third of a million, with nearly 120,000 deaths. In the summer of 1885 cholera also broke out in a viru- lent form in Japan, and, after a cessation during the following winter, recurred with increased fatality in 1886. In the latter year there were over 100,000 deaths from the disease in that country. During 1886 and 1887 cholera continued in Southeastern Italy and in the Austrian dominions at the head of the Adriatic. A few cases occurred in France and Germany, but by stringent sanitary measures an epidemic was averted. In November, 1886, cholera was carried to South America in an Italian ship, the " Perseo," bound from Genoa to Buenos Ayres. The disease rapidly spread in the Argentine Republic, and, crossing the Andean range, invaded the Pacific coast of the South American continent for the second time, reaching Chili and Bolivia and threatening Peru and Brazil. In Chili alone 352 TEXT-BOOK OF HYGIENE. there were over 10,000 deaths in the first six months of 1887. The further progress of the epidemic was arrested and the entire Western Hemisphere is now free from the disease. .From July to December, 1889, cholera prevailed with con- siderable virulence in Mesopotamia. In 1890 it re-appeared in Spain; in 1892 in France and Germany, raging with great vio- lence in Hamburg. Nearly 8000 persons died from the disease in the latter city. Some cases were brought thence to New York Harbor, but the active sanitary measures taken were suc- cessful in preventing its further spread. At the present writing (August, 1894), the disease again threatens Europe. This brief historica.1 sketch of all the epidemics of cholera observed beyond the borders of India demonstrates several facts : first, that the home or breeding-place of cholera is in India, especially the delta of the Ganges, whence it spreads at intervals throughout the world ; second, that it always advances along the lines of travel of large bodies of human beings ; and, third, that it advances, by preference, along water-routes. Exceptions un- doubtedly occur, but the rule is a general one. The disease seems to spread with difficulty along the lines of railroad. When the disease has extended from New Orleans it has always been up the Mississippi Valley, expending its violence upon the river cities Vicksburg, Memphis, St. Louis, and Cincinnati. Several factors must concur before there can be an epidemic of cholera. These are : first, the cholera poison ; second, cer- tain local conditions of air, soil, or water ; and, third, individual predisposition. Without a concurrence of all these conditions no outbreak can occur. If, by any means, the co-existence of these three conditions can be prevented, cholera can be averted. The following are facts bearing upon this question : Cholera is communicated through the agency of a specific poison. This does not admit of doubt. The poison may be either an organic germ, or of an inorganic, particulate, or gaseous nature. The recent researches of Dr. Robert Koch, of Germany, indicate that a micro-organism found in the intestinal discharges of cholera patients and in the bodies of those dead with the disease is the ASIATIC CHOLERA. 353 active agent in propagating the malady. This organism, named by Koch the "comma bacillus," from its general resemblance to a comma, was first discovered by this eminent pathologist in the intestinal contents of cholera corpses in Egypt in 1883, and in the following year more thoroughly studied in Calcutta, whither he had been sent by the German government to pursue his investigations. It has been demonstrated that this germ is always present in the discharges of cholera patients, and up to this time it has not been found in any other disease. Experi- ments upon animals have also shown that cholera can be pro- duced in the latter by introducing the germ into their bodies in various ways. The demonstration of the bacterial nature of cholera seems to be complete. While cholera cannot be regarded as personally contagious in the same sense or in the same degree as small-pox, there can be no doubt that it is spread only by the poison from other cases of the disease. The regularity of its march along routes by which the intercourse of human beings takes place, and always in connection with other cases of cholera, proves this. There is no undoubted case on record where genuine cholera has been spontaneously developed outside of India. That certain local geological^ and perhaps meteorological conditions are necessary for the propagation or virulence of the poison of cholera is beyond dispute. Outbreaks usually take place during the summer or autumn, and nearly always partly or entirely die out during cold weather. Further, in nearly all epidemics, certain cities or towns, or portions of a town, into which persons sick with cholera are brought, and where the poison of the disease is thus imported, remain exempt from the effects of the epidemic. The inference to be drawn from this fact is that in such localities the local conditions are unfavorable to the development of the poisonous germ, and it becomes inert. In India all the local conditions favorable to the propagation of the cholera-germ are found. The filthy personal habits of the people, the overcrowding, the intense heat, the lack of suf- 23 354 TEXT-BOOK OF HYGIENE. ficient, appropriate, or properly-prepared food, and the exten- sive pollution of the water-supply, all combine to produce the necessary conditions of development of the cause of cholera. These conditions, doubtless, to a considerable extent, give rise to that depression of the system which seems necessary to con- stitute the individual predisposition to become infected. Given, then, at any place, a number of persons of a lowered degree of vitality, that is to say, persons not capable of resisting unfavorable influences upon their health under unfavoring con- ditions ; given conditions of climate, water, and soil more or less similar to those existing in India : only the introduction of the third factor, the cholera poison, is needed to cause an outbreak. In many cities of this country and Europe, as proven by the most recent epidemics in Toulon, Marseilles, Naples, and other cities of Italy and Spain, the conditions are present which would furnish the most favorable breeding-place for the cholera-germ if introduced. The dejections and vomited matters of cholera patients con- tain the active agent which produces the disease. The contagi- ous principle contained in these excretions, probably the cholera- germ or "comma bacillus" discovered by Koch, may gain an entrance into the body through the drinking-water or through infected air. Probably both modes are equally competent chan- nels of infection. The prevailing theory is that pollution of the drinking-water is the most frequent source of the rapid spread of the disease. A very striking instance of this occurred in London during the epidemic of 1854, which has already been referred to. 1 Another striking instance of the communication of cholera by polluted water has been reported by Mr. John Simon, long the chief medical officer of the English "Local Government Board." The facts are as follow : The Lambeth Water Company drew its supply from the Thames, at Ditton, above the influence of the London sewage and the tidal flux. The South wark and 1 See ante, page 64. ASIATIC CHOLERA. 355 Vauxhall Company drew its supply from the river near Vauxhall and Chelsea. The water of the Lambeth Company was toler- ably pure, and that of the Southwark and Vauxhall Company was very impure. The water of both companies was distributed in the same district at the same time and among the same class of people, the pipes of the two companies being laid pretty evenly in the same areas, in many places running side by side in the same streets, and the houses supplied being pretty equally distributed. The deaths from cholera in the houses supplied by the Lambeth Company were at the rate of 37, and in the houses supplied by the Southwark and Vauxhall Company at the rate of 130, to every 10,000 persons living. It appears, therefore, that of the drinkers of the foul water about three and a half times as many as those who drank the pure water died of cholera. But the spread of cholera cannot always be referred to pol- lution of the drinking-water. In many epidemics no relation can be shown to exist between the spread of the disease and im- pure water. Professor von Pettenkofer, of Munich, has shown, by a number of carefully-conducted observations, that the prop- agation of cholera often bears a very direct relation to changes in the stage of the subsoil- or ground- water. This does not mean that the subsoil-water is directly or necessarily the agent for the spread of the disease, but that its stage, or variability, now high, now low, may be considered as an index of certain processes going on in the soil which are intimately connected with the propagation of cholera as well as of certain other in- fectious diseases, chief among which is typhoid fever. The relations between the ground-water level and cholera outbreaks in India and various cities in Europe and America give strong support to the views of von Pettenkofer. 1 The relation of the ground-water oscillations to pollution of water in wells, when thoroughly worked out will probably explain discrepancies which at present apparently exist. In addition to the influence of the ground-water oscillations and polluted drinking-water in spreading the cholera-poison, 1 See page 140. 356 TEXT-BOOK OF HYGIENE. must be mentioned articles of food contaminated with the in- fectious matter of the disease. It is also no longer open to question that persons may become infected by handling the clothing and bedding of cholera patients. Laundresses are in special danger from this source. The prophylaxis against cholera comprises such measures as will prevent the admission of the cholera-poison into a com- munity, arrest the development of the poison after its introduc- tion, and reduce the individual susceptibility to attack. It is evident from the foregoing that if the introduction of the cholera-poison could be prevented no outbreak of the dis- ease could occur. With this in view, some have urged the en- forcement of a strict policy of non-intercourse with infected localities. But at the present day few sanitarians advocate these extreme measures. A modified system of restricted intercourse is supported by many authorities, who claim that by the adoption of a thorough system of maritime inspection, disinfection, and observation a rational quarantine, in fact the poison can be rendered ineffective or its entrace into a commmunity prevented. The best authorities, however, think that it is not only easier, but far more effective to place the threatened locality in such a sanitary condition that the development of the cholera- poison cannot take place. The contrast between the effective- ness of quarantine and local sanitation as safeguards against cholera has been well expressed by von Pettenkofer, who com- pares cholera epidemics to powder explosions. The virus of cholera, he says, is the spark that evades the strictest quaran- tine ; the powder is the ensemble of local conditions which pre- dispose to the outbreak. " It is wiser, therefore, to seek out and remove the powder than to run after and try to extinguish each individual spark before it drops upon a mass of powder, and, igniting it, causes an explosion which blows us into the air with our extinguishers in our hands." The measures of local sanitation to be enforced are such as will secure cleanliness of person, of habitation and surround- ASIATIC CHOLERA. 357 ings, of air, of water, and of soil. Pollution of the soil should be especially guarded against, for a polluted soil means impure air arid water, and these mean, if not an infectious disease, at least a heightened receptivity to its influence. The quality of the drinking-water used must be above suspicion of con- tamination by the poison. Unless the latter can be positively excluded all drinking-water should first be boiled. It may then be cooled by pure ice. Filtering the water may not remove the poison. The individual predisposition to cholera is best guarded against by keeping the body clean and well nourished, and the mind free from worry. Underfeeding, anxiety, overwork, ex- posure to extremes of temperature, intemperance in eating and drinking should all be avoided, as they tend to reduce the re- sistance of the system to the influence of the morbid poison. Certain measures of personal prophylaxis which have proven useful heretofore should be adopted wherever cholera prevails. One of the best of these is the use of sulphuric-acid lemonade as a drink. Ten to 15 drops of dilute sulphuric acid in a glass of water, sweetened with sugar, may be drunk instead of water. Experience with it during the epidemic of 1866 has demonstrated its great value as a preventive of cholera. The later researches of Koch have also shown that the "comma bacillus," or spirillum, cannot live in acid solutions. Hence, it is probable that if the contents of the stomacli were always kept acid no infection could occur through absorption from the stomach. A painless diarrhoea, called cholerine, attacks many persons during cholera epidemics. This disorder is easily curable if promptly attended to, but if allowed to run on it may develop into a malignant attack of cholera. Among the means of securing prompt treatment of the poorer classes in times of epidemics is the establishment of numerous public dispensaries, where medical aid can always be obtained. The establishment of such dispensaries and, if 358 TEXT-BOOK OF HYGIENE. possible, of temporary hospitals in the crowded portions of cities is a very important part of the prophylactic treatment. Inasmuch as it seems definitely established that the dis- charges from the stomach and intestines are the active agents in propagating the disease, the immediate disinfection of such dis- charges is vitally important. The stools and vomited matters must be rendered innocuous by germicidal agents, such as mer- curic chloride, carbolic acid, or chloride of lime. Clothing and bedding should be disinfected with super- heated steam, thorough boiling, or fumigation with sulphur dioxide or chlorine. Infected articles of this kind should not be sent to a laundry until they have been thoroughly disinfected by one of the above-mentioned means. Apartments which have been occupied by cholera patients should be thoroughly fumigated, before being re-occupied, with burning sulphur, and afterward freely exposed to the air by opening doors and windows. The walls may also be washed with a solution of mercuric chloride. The most efficient disinfectant is mercuric chloride in the proportion of 1 part in 2000 of the material to be disinfected. The readiest way of securing disinfection with this agent is to add a solution of 1 to 1000 to an equal proportion of the dis- charges to be rendered innocuous. The mercuric chloride acts slowly, and hence the infected material should be exposed to the action of the disinfecting agent for at least two hours before it can safely be thrown into sewers or cess-pools. There are several serious objections to the indiscriminate use of mercuric chloride by the public as a disinfectant. In the first place, it is intensely poisonous, and its perfectly transparent and inodorous solution might readily be accidentally drunk and cause fatal results. To reduce this danger, the Committee on Disinfectants of the American Public Health Association recom- mended the addition of permanganate of potash or of sulphate of copper (blue vitriol) to color the solution. Another serious objection to mercuric chloride is that it cannot be used where ASIATIC CHOLERA. 359 the disinfected material must pass through lead pipe, as this is rapidly corroded by the sublimate. In many water-closets it can therefore not be used. Chloride of lime (bleaching-powder) has been found to be a very rapid and efficient disinfectant, as well as a deodorizer ; but the chlorine, upon which its effectiveness depends, is often so deficient in proportion, and the compound so readily deterio- rates that, unless a preparation can be obtained that contains at least 25 per cent, of available chlorine, it may prove injurious by causing a false sense of security. A trustworthy preparation may be dissolved in water, when required, in the proportion of 1 to 100. An objection to its use is the pungent odor of chlorine, which is very offensive to many persons. Dr. Koch recommends carbolic acid, which he has shown will kill the " comma bacilli " in a dilution of 1 to 20 of water. The ordinary preparations of carbolic acid sold as disinfectants are, however, not to be relied on, many of them not containing more than 2 per cent, of the acid. Further dilution of these agents would altogether destroy their disinfecting power. The purer article is, on the other hand, too expensive to be used as a disinfectant. Little's soluble phenyle is an efficient disinfectant in- the proportion of 2 per cent. (1 to 50). It is furnished of uniform strength, is moderately cheap, non-poisonous, and readily miscible with water. In addition to its disinfecting power, it is also an excellent deodorizer, promptly removing all odors of decomposition and putrefaction. Its only objection is a rather pungent though not unpleasant odor, which somewhat resembles creasote. In the very beginning of an epidemic, prompt isolation of the sick and thorough disinfection of the surroundings of the patient may check the spread of the disease. Much cannot be expected from these measures, however, unless the local sanitary conditions are such as offer a hindrance to the development of the cholera-poison. It is plain, therefore, that prophylactic measures 360 TEXT-BOOK OF HYGIENE. against cholera, to be effective, must be brought into requisition before the epidemic has begun. After the outbreak of the disease it may be too late to put the threatened locality in a good sanitary condition. It is of the highest importance that preventive measures be enforced early. Above all, the purity of the drinking-water must be safeguarded. RELAPSING FEVER. Relapsing fever was first clearly described by Dr. John Rutty, in his " Chronological History of the Weather, Seasons, and Diseases of Dublin from 1725 to 1765." l Near the end of the last and in the first half of the present centuries relapsing fever was frequently met with in an epidemic form in Ireland and Scotland. In 1847 the disease invaded a number of the larger o cities of England. From 1868 to 1873 it prevailed extensively in England and Scotland. On the continent of Europe it was first observed in Russia in 1833. In Germany it was not recognized as a distinct disease until 1847, but did not prevail epidemically until 1868. Since then it has often been observed in that country. Relapsing fever is very prevalent in India, where it was first observed in 1856 by Sutherland. In China and in the countries of Africa bordering on the Red Sea the disease has been recognized by observers. In the United States it was first observed among emigrants in Philadelphia in 1844, and again in 1869. It was conveyed to other places, but has never prevailed extensively in this country. It has not been observed in the United States since 1871. The predisposing causes of relapsing fever are, above all, bad sanitary surroundings. Want and overcrowding seem to be much less important factors than in typhus fever. Although relapsing fever has, since it was first clearly dis- tinguished from typhus and other continued fevers, been recog- nized as an eminently contagious and infectious disease, it was 1 London, 1770. TYPHOID FEVER. 361 not until 1873 that its immediate cause became known. In that year Obermeier discovered in the blood of patients ill with this disease a minute, spiral, mobile organism, now known as the spt'rillum or spirocJiCRte Obermeieri. Obermeier and other observers, prominent among whom is Dr. Henry V. Carter, have demonstrated the constant presence of these organisms in the blood during the attack. Carter and Koch have induced the disease in monkeys by inoculation of the parasite, and Moschutkowski has successfully inoculated it in the human subject. No doubt can exist at the present day that the spirillum of Obermeier is the true cause of relapsing fever. The preventive measures consist in attention to details of personal hygiene ; in other words, local sanitation, disinfection of infected materials (fomites). and complete isolation of the sick. TYPHOID FEVER. The first accurate clinical accounts of typhoid fever date from the seventeenth century, when Baglivi, Willis, Sydenham, and others described cases of fever which in their clinical char- acters correspond to the disease now known as typhoid fever. Strother, however, in 1729, first gave a description of the anatomical characters of the disease, which he says is a " symp- tomatical fever, arising from an inflammation, or an ulcer, fixed on some of the bowels." Bretonneau and Louis, in France; Hildenbrand, in Germany ; William Jenner, in England ; and Drs. Gerhard and Pennock, in this country, clearly pointed out the essential distinction between typhoid and other fevers, during the first half of the present century. At the present day typhoid fever is met with everywhere throughout the world. It is at nearly all times a constituent of mortality tables. It affects by preference persons between the ages of 15 and 30 years, although no age is entirely exempt. It is always more prevalent in the autumn and winter. The disease is probably due to an organic poison, which gains entrance into the body through the respiratory or digestive 362 TEXT-BOOK OF HYGIENE. tract. Recent observations of Eberth, Gaffky, and others seem to indicate that the morbific agent is a micro-organism termed the bacillus typlioideus. The exact relation of this organism to the disease has not been clearly worked out. It is found in the intestinal canal, and especially in the characteristic intestinal lesions of this fever. The infective agent is probably contained in the dejections of patients. The disease is not immediately contagious, like typhus fever. The medium through which the poison is introduced into the body may be drinking-water, food, milk, or other articles containing the infective agent. Localized epidemics due to infected water or milk have been frequently reported. 1 The typhoid poison is supposed to be developed in cess- pools, sewers, and soil polluted by the products of animal decom- position. Whether it ever originates de novo in such places is a much-disputed proposition. At present the evidence is in favor of the view that cases of typhoid fever are always derived from pre-existing cases. The germ may develop in sewers and be carried in the sewer-air from place to place ; it may be carried into the soil from cess-pools receiving typhoid dejections, and there, undergoing development, may ascend through houses with the ground-air, or may drain into wells and pollute the drinking-water. By the admixture of such water with milk or other food the disease may be propagated. It is also believed that the effluvia from typhoid discharges may be absorbed by water or milk, and thus infect these articles. The prophylactic measures against typhoid fever comprise isolation of the sick, prompt disinfection of the discharges, and cleanliness in the widest sense. The water- and food- supplies must be carefully guarded against contamination with the poison, and all decomposing animal matter and excreta must be removed from the immediate vicinity of dwellings. The requisites for prevention may be summed up as pure air, pure water, uncon- taminated food, and a clean soil. 1 See ante, pp. 61-6L TYPHUS FEVER. 363 TYPHUS FEVER. Wide-spread pestilences are nearly always accompaniments of famine and war. Of all pestilential diseases, none is so regu- lar in its coincidence with these conditions as typhus fever. The earliest accounts which unquestionably refer to this disease date from the eleventh century, when it was observed at a number of places in Italy. In the succeeding centuries isolated accounts of it appeared in the chronicles of the times, but no scientific description of it appeared until the sixteenth century. During the seventeenth, eighteenth, and the early part of the nineteenth centuries it prevailed extensively throughout Europe. The constant wars and consequent disturbances of the social rela- tions of the people, famines, overcrowding, filth, excesses of all kinds, contributed largely to the development and spread of typhus fever. For a number of years past no extensive epi- demic of the disease has been observed, although both in this country and in Europe localized outbreaks are frequently met with. Typhus fever is somewhat more prevalent in the winter and early spring months than during the rest of the year, but not very markedly so. At present, typhus fever is nearly always limited to times and places where the conditions favoring its development exist. Wherever overcrowding, in connection with filth, insufficient food, and bad habits are present, typhus fever is likely to be a visitor. Thus, in overcrowded and ill- ventilated emigrant ships, in jails and work-houses, and in camps, especially when stress of weather compels the crowding together of soldiers in close huts or barracks, the disease frequently breaks out. When typhus fever appears in a community, those classes of the people who are subjected to the conditions just mentioned are almost exclusively attacked. In cities, the dwellers in crowded tenements, or in courts and alleys, suffer most severely are, in fact, almost the only ones attacked. An exception must, however, be made in the case of hospital physicians and attend- 364 TEXT-BOOK OF HYGIENE. ants where typhus-fever patients are treated. The mortality among these is always large. Typhus fever is contagious and infectious. An exposure for a length of time to an atmosphere impregnated with the poison may suffice to induce an attack. The poison may also be conveyed from place to place in fomites. Physicians may carry it in their clothing, if they have been exposed to a typhus atmosphere. The prevention of typhus fever consists in the institution of such measures as will secure pure air, pure water, a clean soil and dwellings, and cleanliness of body and clothing. When an outbreak occurs, the sick should be promptly isolated, the well persons removed from the building in which the cases have occurred, and efficient measures of disinfection carried out. The sick should be treated in the open air as much as possible. YELLOW FEYER. The West India Islands, the Gulf coast of Mexico, the northern part of the Atlantic coast of South America, and a limited section of the west coast of Africa constitute the present home of yellow fever. From this area (the so-called " yellow- fever zone ") the disease is frequently transported to contiguous or distant countries. The South Atlantic and Gulf coasts of the United States and the shores of the Caribbean Sea are most liable to the epidemic visitation of this pestilence. The first trustworthy account of an epidemic of yellow fever dates from the year 1635, when it prevailed on the Island of Guadeloupe. This and the adjoining islands of Dominica, Martinique, and Barbadoes were invaded a number of times in the fifty years following the above date. Jamaica was invaded in 1655 and Domingo the year after. In 1693 the first appear- ance of the disease is mentioned in the United States, being observed in Boston, Philadelphia, and Charleston. In 1699 it appeared as an epidemic in Vera Cruz, and re-appeared in Phila- delphia and Charleston. Since the year 1700, the disease has YELLOW FEYER. 365 appeared in an epidemic form, at one or more places within the present limits of the United States, eighty times, the last consid- erable invasion being at Jacksonville and other places in Florida, and Decatur in Alabama, in 1888. In South America yellow fever appeared for the first time in 1740. In 1849 the disease was imported into Brazil, and has since then been endemic. Peru and the Argentine Republic have also suffered several severe visitations of yellow fever since 1854. On the west coast of Africa, yellow fever seems to be en- demic in the peninsula of Sierra Leone, where it has been fre- quently observed since 1816. It has also prevailed epidemically in Senegambia and a number of the islands off the northern portion of the west African coast. In Europe, Spain and Por- tugal have been the only countries to surfer from yellow-fever epidemics. Although the causes of yellow fever cannot be definitely stated, it is well-known that it only occurs endemically within the tropics, and prevails epidemically elsewhere only during the summer. Of 180 epidemics observed in the United States and Bermudas, 154 began in July, August, and September. Of the remaining 26, none began in the six months from November to April. A temperature of 26 C. and a high humidity are gener- ally considered essential to produce an outbreak of the disease. Of other necessary meteorological conditions nothing is known. That the specific cause of yellow fever is a micro-organism appears probable from a consideration of the clinical history of the disease and its mode of propagation. Up to the present time, however, none of the various organisms described as causa- tive have made good the claims advanced by their discoverers. Surgeon-General Sternberg has shown that neither the organism of Freire, of Carmona, of Babes, of F. S. Billings, of Finlay, or of Gibier is the true cause of yellow fever. It seems to be well established that the most filthy and 366 TEXT-BOOK OF HYGIENE. insanitary portions of cities are those principally ravaged by yellow fever. The author is convinced from personal observa- tion in Savannah, Memphis, and New Orleans, that filth is one of the principal 'factors in the spread of yellow fever. This opinion is also forcibly expressed by many of the most eminent authorities on the subject. Yellow fever is not endemic within the limits of the United States, and has probably never originated here. The instances in which it has appeared to do so may be explained by the per- sistence of the morbific agent through one or more winters, or by a new importation which has escaped observation. Yellow fever frequently breaks out on shipboard and causes much loss of life. There is no evidence that it originates on ships ; it is only acquired after intercourse with an infected ship or infected place. The question of the personal contagion of yellow fever has been decided negatively. The disease is infectious and its cause may be transported in fomites, but persons sick with the disease do not communicate it. An infected atmosphere, or one favor- able to the poison, is necessary to the propagation of the disease. The preventive measures indicated against yellow fever appear from the foregoing: they are strict sanitary inspection to prevent the introduction of a person sick with the disease ; to prevent the introduction of clothing or other fomites from a suspected locality without thorough disinfection, and such a con- dition of public and private sanitation as will prevent the devel- opment of the poison, should the latter, perchance, be introduced. When the disease becomes epidemic in a city, the inhabi- tants should be removed to temporary camps beyond the infected area. The experience of the city of Memphis in 1879, and of various localities in Florida in 1888, encourages the hope that by prompt depopulation of cities and strict enforcement of sani- tary measures in the camps the terrors of yellow fever can be largely averted. The sick should be promptly isolated, and no one except attendants permitted to have intercourse with them. SCARLET FEVER AND MEASLES. 367 SCARLET FEVER AND MEASLES. The early history of these two contagious eruptive fevers is inextricably blended together. Up to the latter half of the seventeenth century the distinction between the two was not made by writers. Sydenham was among the first who clearly separated scarlet fever from measles and gave it a distinct name. Since the great English Hippocrates, the essential character of scarlet fever has been recognized by all physicians, and it is now never, or but rarely, confounded with measles. Of the two diseases, measles is somewhat more generally prevalent, although both occur usually in epidemics. There is hardly a country in which measles has not been observed, while the continents of Asia and Africa have remained measurably exempt from scarlet fever up to the present time, although epi- demics have been recorded in India and Japan. Hirsch states that scarlet fever was first observed in this country in 1735, at Kingston, Mass., quoting as authorities Dr. Douglass, of Boston, and Dr. Golden, of New York. The latter, however, in a letter to Dr. Fothergill, 1 clearly describes diphtheria, and not scarlet fever. Its distribution is now general, but it is said to be much milder in the southern than in other portions of the United States. The prevalence of measles is not limited to any geographical section. Epidemics of measles usually begin during cold weather. Of 530 epidemics observed in Europe and North America, 339 occurred during the colder and 191 during the warmer months. In 213 of these, the height of the epidemic occurred 135 times in winter and spring, and only 78 times during summer and autumn. Scarlet fever epidemics occur more frequently in autumn than at any other season. The cause of scarlet fever or of measles is not to be sought in climatic influences, insanitary surroundings, or special natural conditions of air, water, or soil. Both diseases are contagious and infectious, and the contagion is transmitted either 1 Medical Observations and Inquiries, vol. i, p. 211. London, 1776. 368 TEXT-BOOK OF HYGIENE. by fomites (clothing, letters, etc.), infected air, drinking-water, or milk. Several observers have claimed the discovery of the specific organism of scarlet fever, but no trustworthy evidence has yet been furnished that the problem is solved. On a previous page (93) reference has been made to the probable connection between a disease of milk-cattle and scarlet fever. The measures for the prevention of both diseases are isola- tion and thorough disinfection. DIPHTHERIA. Under the names of Syriac and Egyptian ulcers, Areta-us, a writer of the second century, described various forms of malig- nant sore throat. The disease now called diphtheria prevailed at various places in Europe during the Middle Ages. In this country it was first observed about the middle of the last century, and in 1771 Dr. Samuel Bard, of New York, described it very accurately. Although repeated severe outbreaks occurred in Europe in the early part of the present century, it was not until 1857 that it again attracted attention by its epidemic prevalence in the United States. Since that time it has spread throughout the country, and is at present one of the most generally diffused, as well as one of the most fatal, of the contagious diseases. In certain epidemics its malignancy is very marked, while in others it seems to be a rather mild affection. Diphtheria is personally contagious; it may be transmitted by inoculation, as well as by inhaling an infected atmosphere. The infecting agent is most probably the micro-organism first described by Lofner. The bacillus cannot always be demon- strated, and is, further, likely to be confounded with non-patho- genic organisms possessing similar morphological characters. The question as to the identity of diphtheria and croup is not merely a clinical one, but has an important bearing upon preventive medicine. If croup is a non-contagious and non- infectious disease, as is held by many, no precautions will be DENGUE. 369 necessary to prevent its spread to healthy persons. If, on the other hand, diphtheria and croup are identical in nature, the danger of infection is equally great in both diseases. Inasmuch as it is frequently impossible to positively decide upon a diagnosis, it would be well to consider the identity of the two diseases as established, and act, as far as preventive measures are concerned, as if all were cases of diphtheria. Diphtheria is inoculable upon animals, and may through this medium be transmitted to man. Persons sick with diphtheria should be carefully isolated ; no one but the immediate attendants should be allowed to come in contact with the patients. Table utensils, bedding, and cloth- ing used by the sick should be thoroughly disinfected by steam or boiling water before being used by others. Intimate contact with the sick, such as kissing, should be strictly prohibited. There seems no room to doubt that the virus of the disease can also be carried in the clothing. Hence, physicians and nurses should be especially careful in personally disinfecting themselves after contact with a case of diphtheria. After death or recovery of the patient, the apartment occupied during the illness should be disinfected with chlorine or sulphurous-acid gas. Children recovering from diphtheria, scarlet fever, measles, or small-pox, should not be permitted to attend school for at least four weeks after recovery. It is believed that there is danger of infection for a period about as long as this, and, besides, the patients are apt to be weakened from the effects of the dis- ease, and not able to resist the strain of continuous mental effort. DENGUE. The disease known as break-bone fever, dandy fever, and by various other names, was first observed in the United States in 1780 by Dr. Benjamin Rush. Dr. Rush describes an epi- demic which prevailed during the summer and early autumn of that year under the name of " bilious remittent fever," but the symptoms of the disease hardly leave any doubt that it was 24 370 TEXT-BOOK OF HYGIENE. dengue. In 1779 and 1780 it was also observed on the Coro- mandel coast, in Egypt, and on the island of Java. In 1784 to 1788 dengue also prevailed in various cities of Spain. In 1818 an epidemic appeared in Lima, in which nearly every one of the 70,000 inhabitants was attacked. In 1824-25 the disease again prevailed widely in India, where it was known as the " three-day fever." Isolated out- breaks occurred in that country until 1853, when it again ap- peared as a wide-spread epidemic, and in 1872 another epidemic outbreak occurred in the East, extending from Eastern Africa to Arabia, India, and China. In 1826 an epidemic of dengue appeared in Savannah, and in the following two years spread over the southern portion of the United States and the West Indies, reaching the northern coast of South America. In 1845 to 1849 the disease was observed in Rio Janeiro; in 1848 to 1850 in the South Atlantic and Gulf States. In 1854 it was observed in Southern Alabama, and in the same year in the West Indies. In 1873 another epidemic appeared in the lower Mississippi Valley, and in 1880 an outbreak of some extent occurred in New Orleans, Charleston, and other places on the Gulf and South Atlantic coasts. Dengue always begins in the summer or early autumn, and ceases abruptly with the advent of cold weather. It is almost exclusively limited to hot countries. It spreads with extreme rapidity wherever it appears. It is not contagious ; the man- ner of its propagation is not known. The susceptibility to the disease appears to be almost universal ; it frequently prostrates the majority of the inhabitants where an outbreak occurs. During the epidemic in Calcutta in 1871-72, 75 per cent, of the population were attacked. In the United States similar epi- demics have been repeatedly observed. Dengue is rarely fatal. It seems to be propagated through the atmosphere. No measures of prevention are known or available. EPIDEMIC INFLUENZA. 371 EPIDEMIC INFLUENZA. Accounts of epidemic influenza can be traced back to the year 1.173, when the disease was observed coincidently in Italy, Germany, and England. It has prevailed epidemically, at vary- ing intervals, to the present time. In the fourteenth century 3 epidemics are recorded ; in the fifteenth, 4 ; in the sixteenth, 7 ; in the seventeenth, 46. Of these, 15 were very extensive, some of them prevailing over both hemispheres contempo- raneously. On the American continent influenza was first recorded in 1627, when it prevailed in New England, where it again broke out in 1625. Following this there is no notice of the disease in America until 1732, when an epidemic began in the New England States, which extended over the entire globe. Epi- demics occurred during the remainder of the eighteenth cen- tury in 1737, 1757, 1761, 1767, 1772, 1781, 1789, and 1798. During the present century the disease has prevailed more or less extensively in this country at thirteen different times, the last epidemic of any considerable extent being in 1879. In November, 1889, an epidemic began in Russia which rapidly spread throughout Northern Europe, reaching the United States about the beginning of 1890, recurring in 1891 and 1892. The epidemic was complicated in many cases by pneumonia of a fatal character. The disease manifested itself in two principal forms, the catarrhal and the nervous. Weichselbaum, of Vienna, claims to have discovered a micro-organism which he believes to be the cause of the affection, but this claim has not yet been verified. A curious feature of epidemics of influenza is the coinci- dent occurrence of outbreaks of a somewhat similar affection among animals, horses and dogs being especially attacked. Influenza is an acute, specific, infectious disease, not di- rectly contagious. The infection is apparently produced or trans- mitted in the air. The disease frequently appears over a large area of country almost simultaneously. Peculiarities of climate, season, meteorological conditions, geological formation, or racial 372 TEXT-BOOK OF HYGIENE. characteristics have no apparent influence upon the causation or spread of the disease. It occurs more frequently in the winter and spring than during the summer or autumnal months. The investigation into the epidemic of influenza among horses, re- ferred to in a previous chapter, 1 seems to indicate, however, that a moist and impure atmosphere intensifies the disease. No measures of prophylaxis can be indicated except avoid- ance of anything tending to depress the vital powers. EPIDEMIC CEREBRO-SPINAL MENINGITIS. This disease was first recognized in Geneva in 1805. In the following year it was noted in various places in the United States. Both in Europe and this country localized outbreaks of the disease occurred between the dates above mentioned and 1816. At this time the disease seemed to die out altogether, but in 1822 it re-appeared in various parts -of Europe and America. Cerebro-spinal meningitis appeared in 1857 in the south- west of France, and during the following ten years spread over a large part of the country. Algiers, Italy, Denmark, and Ire- land were also visited by the scourge. In 1854 and 1861 Sweden experienced its ravages, and in 1859 Norway was invaded by the disease, which continued for nearly a decennium in the latter country. From 1860 to 1867 the disease prevailed in Holland, Portugal, Germany, Ireland, and Russia. After the termination of what may be called the first epi- demic, in 1816, cerebro-spinal meningitis was not again observed in this country until 1842. In the eight years succeeding, it prevailed epidemically throughout almost the whole United States. From 1861 to 1873 it was noted frequently in various parts of the country. Since the latter year the reports of its occurrence in this country have been limited to sporadic cases or localized outbreaks. Cerebro-spinal meningitis is an acute infectious disease, 1 Chapter I, p. 29. SYPHILIS. 373 very fatal in its tendency. It is probably not personally con- tagious. Climate has no influence upon its origin, but season seems to stand in a positive relation to its causation. About three-fourths of the epidemics noticed have occurred during the winter and spring months. The disease seems to show no preference for peculiarities of topographical or geographical formation. Overcrowding, overwork, and uncleanliness have an important influence in determining an outbreak. It is especially a disease of youth and adolescence. Out of 975 cases occurring in New York only 150 were over 20 years of age, while of the remainder 665 were under 10. The prophylactic measures to be adopted against cerebro- spinal meningitis consist in careful attention to the sanitary conditions of dwellings and streets, avoidance of overwork and overcrowding during times of epidemic, isolation of the sick, and disinfection of the sick-room after the termination of the disease. SYPHILIS. In the year 1494, Charles VIII, of France, in command of a large army invaded Italy, and early in the following year be- sieged Naples. During the investment of the city a very severe disease, characterized by ulcers of the genitals, violent pains in the head and limbs, and generalized cutaneous eruptions broke out among the besiegers and spread rapidly throughout the army and civil population. On the return of the army to France, after the termination of the war, the disease rapidly spread throughout Europe, and the literature of the early part of the sixteenth century, both medical and lay, teems with references to it. From the locality and other circumstances connected with its epidemic appearance the disease acquired various names. Thus, the French called it morbus Neapolitanus, or mal d 'Italic, while the Italians termed it morbus Gallicus, or mala Franzos. At a very early period it was, however, clearly recognized that the disease was communicated during sexual intercourse, and 374 TEXT-BOOK OF HYGIENE. hence it was usually described in medical writings under the name lues venerea, while in the popular literature it still figured as the Frenchman's disease (morbus Gallicus). The name syphilis was first used in a poem descriptive of the disease, written in 1521 by Fracastor, a physician of Verona. The extraordinary outbreak of the disease toward the end of the fifteenth century led to many speculations concerning its origin. As it attacked persons in all ranks and conditions of life, " sparing neither crown nor cross," in the words of a con- temporary poet, the favorite explanation was that meteorological influences had much to do with its causation. Many ascribed it to the malign influence of the stars. The Neapolitans attrib- uted it to the wickedness of their enemies, the French, while the latter laid the blame on the filth and immorality of the Italians. The Spaniards claimed that it had been imported from America by Columbus, whose first expedition returned to Europe in 1493. There are records, however, which prove that the dis- ease already existed in Italy in the latter year. In other parts of Europe the Jews, who had been driven out of Spain: by the terrors of the Inquisition, were accused of this, as of many other misfortunes which befell the people. When it was definitely established that the disease was communicated almost solely by sexual intercourse, the theory of its transatlantic origin became very popular. It is characteristic of human nature to refer the origin of troubles resulting from its own vices to some other source, if possible. This theory of the American origin of syphilis is still held by some writers. Within a few years, Dr. Joseph Jones, of New Orleans, claims to have found evidences of syphilitic disease in the skulls and other bones from some of the prehistoric Indian mounds in Mississippi. These observa- tions of Dr. Jones have, however, not yet been verified by others. Although the first great epidemic of syphilis is clearly trace- able to the period between the years 1493 and 1496, an ex- amination of the older literature reveals many descriptions of disease which can only be explained by assuming them to refer SYPHILIS. 375 to syphilis. The Old Testament Scriptures contain numerous references to diseases of the genital organs. In most instances these troubles are ascribed to the wrath of God, although in some cases a pretty shrewd hint is given as to the causation of the affections. Finaly 1 remarks that the Hebrew word trans- lated in all versions of the Bible by "flesh" signifies also the virile member. In this light, the references in Leviticus, XIII XV; Numbers, XXV, 1-9, XXXI, 16-1 8; Deuteronomy, IV, 3 ; Joshua, XXII, 17 ; I Samuel, V, 6, 9, 12 ; Psalms, CVI, 28-30 ; I Corinthians, X, 8; Ephesians, II, 11 ; and Colossians, II, 13, receive a new interpretation. Numerous innuendoes in the Latin classics, and more or less exact descriptions in the medical writings of Greece, Rome, China, and India, leave no room for doubt that venereal diseases, and probably among them syphilis, have existed from the earliest times. At the present day syphilis is the most widely prevalent of all, contagious diseases. In 1873 Dr. F. R. Sturgis estimated that in New York 1 person out of every 18 suffered from it. This is considered a moderate estimate. Dr. J. Wm. White, of Philadelphia, pronounces the opinion that "not less than 50,000 people of all classes in that city are affected with syphilis." On this basis Gihon estimates the number of syphilitics in the United States at one time at 2,000,000. 2 The disease is transmitted, in the vast majority of cases, during the performance of the sexual act, but there are numerous other ways in which it may be and frequently is communicated. In the special literature of the subject are records of many cases in which the disease was acquired through a kiss, a bite, the act of suckling (from infant to nurse, and conversely), using a pipe, glass-blowers' mouth-piece, the finger of a midwife, the instru- ments of the dentist or surgeon, inoculation of syphilitic secretion mixed with saliva in the process of tattooing, and many other ways. Numerous cases have been reported where physicians were inoculated on the finger while examining a syphilitic patient. 1 Arch. f. Dermat. u. Syphilis, II Jahrg. 1 Heft., p. 126. The Prevention of Venereal Diseases by Legislation, Sanitarian, June, 1882. 376 TEXT-BOOK OF HYGIENE. The prophylactic measures which suggest themselves from a consideration of the nature of the disease are isolation of those infected, regular inspection of the class of persons through whom the disease is most frequently transmitted, t'.e., prostitutes, and individual precautions against acquiring it. Greater attention to cleanliness of the genital organs on the part of those indulg- ing in promiscuous intercourse would aid largely in reducing the number of cases of syphilis. DISEASES OF ANIMALS COMMUNICABLE TO MAN. Sheep-pock. This is a highly contagious and infectious disease of sheep, resembling, in its symptoms, course, and fatality, small-pox as it occurs in the human race. It is believed by Bellinger to be different from the form of small-pox produced in sheep, goats, horses, and other animals by the inoculation of human small-pox. Sheep-pock can be inoculated upon other animals and man, but only produces a local disease at the point of inoculation in the latter. Sheep may be protected against this disease by inoculation with sheep-pock virus (ovination), or by vaccination with vaccine lymph. The peculiarity of sheep vaccinia is that it is a more or less generalized disease, the pustules being distributed over the body. Sheep-pock, when inoculated upon human beings, does not produce a generalized infectious disease, but remains entirely local. Actinomycosis. Veterinarians have frequently observed a disease attacking the jaws of cattle and producing tumors, often with ulcerated surfaces. The bone is usually involved. The disease has heretofore been generally considered a sarcomatous growth. It is not seldom observed among the cattle in the western stockyards, where it is known in the vernacular as " swell-head." Recent investigations by Ponfick have shown that the growth consists of a vegetable parasite (actinomyces), and that it is inoculable upon other animals, and may be conveyed to man. A considerable number of cases have been observed in human beings in Germany, where the disease was DISEASES OF ANIMALS COMMUNICABLE TO MAN. 377 first described by Ponfick, and .very recently 4 cases have been reported in this country. 1 Bovine Tuberculosis (Perlsucht). In cattle, tuberculosis occurs in two forms, miliary tubercles and cheesy masses in the lungs, and firm, pearly nodules on the serous membranes. These nodules do not break down, but may become calcified. Bovine tuberculosis is a frequent disease among cows kept in damp, dark, and ill-ventilated stables. The disease, which is essentially the same as human tuberculosis, tubercle bacilli being present in the neoplasms, is believed by many to be trans- missible to human beings by means of the milk or flesh of tuberculous animals. The sale of the meat of tuberculous cattle should be prohibited. Rabies. Hydrophobia in the brute, and its communi- cability to man through a bite, has been known from the remotest antiquity. It occurs in dogs, foxes, wolves, horses, and other animals, and may be transmitted from any of them to human beings. The contagium of rabies, the infective poison, is contained principally in the saliva, and is usually inoculated by the teeth of the mad animal. Pasteur has shown that the greatest virulence of the rabies poison resides in the brain and spinal cord of the animal suffer- ing from the disease. By cultivation of this virus, the nature of which has not yet been definitely determined, its virulence could be diminished, and by inoculation of men and animals with the attenuated virus protection against the disease could be secured. The fact seems likewise established that the period of incubation of the inoculation-rabies is much shorter than that acquired in the usual way by bites of rabid animals. Hence, inoculation with the attenuated virus protects the bitten individ- ual against the fatal outbreak of the unmodified disease. Anthrax. Anthrax, or splenic fever (milzbrand), is an 1 Boston Med. and Surg. Journal, Oct. 16, 1884, p. 377, and Journ. Am. Med. Ass'n, Nov. 27, 1886. Also, N. E. Med. Monthly, Sept. 15, 1886. 378 TEXT-BOOK OF HYGIENE. acute, highly contagious and infectious disease of herbivorous animals, which may be transmitted by Inoculation or the ingestion of the virus to other animals and to man. The disease is due to a minute vegetable organism which is found in the blood and tissues of the diseased animals. This organism, bacillus antJiracis, was first discovered by Pollender, and has been thoroughly investigated by Davaine, Pasteur, Koch, and others. Inoculation of these bacilli or their spores always produces the disease in susceptible animals. Skins of animals not infre- quently contain the virus, which may then gain access to the blood of persons engaged in handling them. Knackers, butchers, wool-sorters, and other persons liable to come in contact with sick animals, or handling their flesh or hides, are subject to the infection, either by direct inoculation (through abrasions of the skin, etc.) or by inhalation of the spores of the bacillus. An intestinal form of anthrax in man, mycosis intes- tinali-8, is sometimes produced by the consumption of meat of animals suffering, when killed, of splenic fever. Numerous instances have been reported. The diagnosis has been verified by discovering the bacillus of anthrax in the blood and various organs of the individuals attacked. In view of the dangerous character of the disease, persons coming in contact with animals suffering from anthrax should be warned of their peril. In order to protect other animals in a herd, strict isolation of the infected, thorough disinfection of the stables occupied by them, and deep interment of the cadavers of those dead from the disease are indicated. Glanders. Glanders, or farcy, is a very fatal contagious disease of horses which may be communicated to other animals and to man. The cause of glanders has recently been discovered by Loffler to be a bacillus resembling the bacillus tuberculosis. Pure cultures of this bacillus were inoculated into animals, and followed by glanders in a number of the cases. The infection in man may occur either upon the seat of DISEASES OF ANIMALS COMMUNICABLE TO MAN. 379 excoriations of the skin or mucous membranes, especially those of the nose, conjunctiva, and possibly by inhalation of infective particles floating in the air. Animals with glanders should be promptly killed and their cadavers cremated or deeply buried. No part of the body of any animal dead with glanders should be allowed to be used. Infected stables should be thoroughly disinfected. [The works of especial value to students who desire fuller information upon the subjects treated in this chapter are the following : Hirsch, Handbuch der Historisch-Geographischen Pathologic, 2te Aufl., Stuttgart, 1883. Haeser, Geschichteder Epidemischen Krankheiten. Hecker, The Black Death, translated b}' B. G. Babington. Rohlfs, Die Orientalisohe Pest. Marson, " Small-pox," in Reynolds's System of Medicine, vol. i. Seaton," Vaccination "ibid. Trousseau, Clinical Medi- cine, vol, i. Fifth Annual Report of Illinois State Board of Health. Hardaway, Essentials of Vaccination. Crookshank, History and Pathol- ogy of Vaccination, Woodworth and McClellan, Cholera Epidemic in United States in 1873. Chailld, "Report of Yellow Fever Commission," Annual Report National Board of Health for 1880. Wood and Formad, " Memoir on the Nature of Diphtheria," ibid., 1882. Thompson, Annals of Influenza. Stille, Epidemic Meningitis. Mueller, Die Venerischen Krankheiten im Altherthum. Lancereaux, Traite de la Syphilis. Bollinger, " Ueber Menschen u. Thierpockeii," etc., Samml. klin. Vortr., No. 116. Ponfick, Die Actinomycose des Menschen. Gamgee, " Hydro- phobia and Glanders," in Rej^nolds's System of Medicine, vol. i. Bollinger, " Anthrax," in Ziemssen's Cyclopaedia, vol. iii. E. O. Shakes- peare, Report on Cholera in Europe. Surgeon-General G. M. Stern- berg, Etiology and Prevention of Yellow Fever. Ernest Hart, " Water- borne Cholera," Journ. Am. Med. Ass'n, July 1. 1893.] QUESTIONS TO CHAPTER XIX. HISTORY OF EPIDEMIC DISEASES. Of what advantage is the study of the history of epidemic dis- eases ? What are some of the most important maladies of this class ? To what are they all due ? What are some of the synonyms of the Oriental plague? What are some of its characteristic symptoms ? What is the date of the first clear account of it ? How long did this epidemic persist ? When did it make its second incursion into Europe? What was one of the peculiar symptoms of this epidemic ? What was its estimated mortality ? What were some of its moral effects ? When was its final incursion into Western Europe? What minor epidemics of it have there been since? When was the last, and where ? Is it now endemic anywhere ? To what was its origin formerly ascribed? What conditions are always present when the plague prevails? What is another evident factor in its causation ? How is it generally transmitted ? Is it a germ disease ? What are the measures of prevention therefore indicated ? What is the sweating sickness ? What are some of its character- istic symptoms and peculiarities? What is evidently its nature? Is there any class exempt from it ? What favors its spread? What rela- tion has it to cholera? When did it first appear in England ? When for the last time? Where has it appeared since? Have there been many outbreaks in Europe ? What are the earliest details regarding small-pox ? When was it supposed to have been introduced into Europe? Who made the first distinct reference to it in medical literature? AVhen ? What was the estimated mortality from this disease in Europe previous to the intro- duction of vaccination ? Where has it been very fatal in" its devastations in recent years ? What other countries and peoples have suffered from it ? What is the mortality from unmodified small-pox ? How is the dis- ease transmitted? What factors are necessary to cause an outbreak? What may carry the poison? For what distance about a patient may the air be infectious ? In what stages of the disease is it contagious ? What races are more commonly attacked, and among which is it more fatal ? Does one attack of small-pox always confer future immunity from (380) QUESTIONS TO CHAPTER XIX. 381 the disease ? Wherein is the popular belief, that persons suffering from an acute or chronic disease are less liable to incur small-pox than the healthy, at fault ? Which maladies are most likely to afford this immunity ? When does such immunity appear to cease ? When do epidemics of small-pox usually begin ? In what seasons do they spread most rapidly? Does the disease spread rapidly at first? Has the specific organism of small-pox been certainly discovered ? When was the first attempt to limit the fatality of small-pox by in- oculation made in Europe? When was the practice .introduced into England, and by whom ? What were the details of the method as then practiced ? What were the characteristics of the disease thus produced ? Was the practice altogether without danger to the one inoculated ? What other grave objection was there to such inoculations ? When was the practice of inoculation introduced into America, and by whom ? How long was it continued in England and in America? Where was it practiced before its introduction into Europe? What led to the discovery of vaccination ? Who first practiced it ? When ? To whom is due the merit of demonstrating and publishing the value of vaccination ? When did he perform his first vaccination, and with what results? When did he publish the first pamphlet in rela- tion to it ? When was vaccination introduced into America, and by whom ? What is the relation of vaccinia (cow-pox) to small-pox ? What are the symptoms produced in the case of a successful vaccination ? When may the individual be considered to be thoroughly protected? Is the immunity absolute for life? What is the character of an attack of small-pox in an individual who has once been vaccinated ? Does repeated vaccination increase the immunity ? What effect has vaccina- tion had on the mortality from small-pox ? On the prevalence of the disease ? What important precaution should be observed in all vaccinations ? Why ? When should children be vaccinated ? When should they be re- vaccinated ? What are some of the peculiarities following upon revacci- nation ? What are some of the objections urged against humanized virus ? Are these all valid ? What are some of its advantages ? How is it to be inoculated ? How is animal virus obtained ? How is it to be used ? In what way do the results from using it differ from those of humanized virus ? What complications are likely to occur in the course of the vaccinia? What are some of the causes of these complications ? What subjects are unfavorable ones for vaccination ? When may vaccination be properly 382 QUESTIONS TO CHAPTER XIX. delayed ? What diseases may be communicated by or may follow vacci- nation ? What cases should be promptly revaccinated. What besides vaccination is highly important in the prophylaxis of small-pox ? What precautions should be observed in the care of one sick with small-pox ? What are the best disinfectants for such cases ? When is all danger of infection over ? Where is Asiatic cholera endemic? What can be said of its ravages there ? When were the first authentic accounts of it given ? When did the disease first become epidemic outside of India? What were some of the countries visited ? When did it first appear in England ? When and where in America ? When did this outbreak from India end ? When did it again become pandemic, and how long before it again reached the United States? What were the ports through which it entered? How long did it persist in this country ? How long in South America ? When was the next visitation to this country ? What parts of South America were first invaded at this time ? Where else was cholera raging during these periods, and where was it practically endemic ? When was the last serious importation of the disease into this country, and by what port did it enter? Where else, and when, have there been important epidemics since this date ? What does the history of all these epidemics demonstrate ? What factors must concur that there may be an epidemic? What is the specific cause of cholera? Who discovered it? When? Is the disease contagious? How is it spread ? What con- ditions seem to be necessary for its propagation ? When do outbreaks usually occur, and when do they subside ? Why is the disease endemic in . India ? How do these conditions predispose the victims to the disease ? Are these conditions peculiar to India? Where else may they exist ? How is the specific organism given off from the human body ? How does it usually gain entrance into others ? What evidence is there of this (see chapter on Water) ? What other agencies may aid in disseminating the disease ? What are the measures of prophylaxis against cholera ? How can the entrance of the disease into a community be prevented ? What measures of local sanitation may be even more effective ? Why? How shall the drinking-water and food be rendered harmless ? How may one guard against an individual predisposition to cholera? What measure of personal prophylaxis is useful ? What is the rationale of this ? What disease may simulate cholera during an epidemic, and to what is it often due ? In times of cholera epidemics, what sanitary measures are to be es- tablished ? What disinfectants are to be used ? What articles are to be QUESTIONS TO CHAPTER XIX. 383 disinfected, and how ? What are some of the objections to the indis- criminate use of the bichloride of mercury ? What may be used in its stead ? What does Koch recommend, and what objection is there to its use ? What plan should be pursued at the beginning of an epidemic ? When was relapsing fever first described? When was it first observed in America? When did it last appear here? What predis- posing conditions favor it ? What is its specific exciting cause ? Where is the germ found ? What are the preventive measures to be used against relapsing fever? How long has typhoid fever been known as a distinct disease? Where is typhoid fever common ? When is it most prevalent ? What persons and ages are most subject to it? To what is the disease due? Where is it found? Is the disease contagious? Where is the poison developed ? Does it arise de novo? How may the poison be conveyed to human beings ? What prophylaxis may be employed against typhoid fever? What are the requisites for prevention? When were the earliest authentic accounts of typhus fever made ? What predisposing conditions favor its development and spread ? When is it more prevalent ? By what is it limited ? Where is it apt to occur ? What class of persons is most likely to be attacked? Is it contagious? How may it be prevented ? What measures are to be pursued during an outbreak of the disease? Where is the present home of yellow fever ? What localities are most liable to epidemics of this disease ? What is the date of the first authentic account of it? When and where did it first appear in the United States? Has it ever originated here or been endemic? How many times has it been epidemic in this country in the last two centuries ? When and where was the last epidemic ? In what season do epidemics occur? In what climates may it be endemic? What climatic conditions seem to be necessary for an outbreak ? What is probably its specific cause ? Has this been discovered ? What is one of the principal factors in its spread ? Is the disease contagious ? How is the poison conveyed ? What is necessary to the propagation of the disease? What preventive measures are to be employed against yellow fever ? What is to be done, should the disease become epidemic in a city ? Will this be efficacious in most cases? Who first distinguished between scarlet fever and measles ? Which disease is more prevalent ? What countries have been practically exempt from scarlet fever? When was scarlet fever first observed in America? When do epidemics of measles usually begin? When of scarlet fever? What is the exciting cause of each disease, and how may it be conveyed ? 384 QUESTIONS TO CHAPTER XIX. Have bad hygienic surroundings an influence in the propagation of either disease ? What are measures for prevention in both cases ? How old is the history of diphtheria? When was it first observed in this county ? When did it again prevail epidemically here ? How are various epidemics marked ? Is it contagious ? How may it be con- veyed ? What is the exciting cause? Is diphtheria identical with croup? What plan should be pursued for prevention regarding the two diseases ? Is diphtheria transmissible to animals ? What precautions should be taken with a person sick with diphtheria? How long should children who have had diphtheria, scarlet fever, small-pox, or measles be detained from school ? Why ? What is dengue ? When and by whom was it first observed in the United States ? When does an epidemic begin, and when does it stop ? To what countries is the disease limited ? Is it contagious ? How is it propagated ? Who are susceptible ? What are the measures of preven- tion that may be employed? Is the disease fatal? What is the date of the earliest accounts of epidemic influenza? What are some of its synonyms ? When did it first prevail in America? When was the last epidemic ? How was this one complicated ? Are ani- mals subject to this disease? Is it contagious? How is it transmitted ? When is it most prevalent ? What are the measures of prophylaxis against it ? When was epidemic cerebro-spinal meningitis first recognized? When did it appear in America? When was the first epidemic here? When the next? When the last? Is it contagious or infectious? What is its tendency ? When is it most liable to occur? What influence has climate upon it? What factors seem to favor an outbreak ? What ages are most subject to it? What is the prophylactic treatment? When and where does syphilis seem to have had its origin? Are there any traces of evidence of its existence before this ? What can be said of its comparative prevalence ? How is it usually transmitted ? In what other ways may it be conveyed ? What prophylactic measures are indicated ? What are some of the serious diseases of animals communicable to man ? What is sheep-pock, and what is its peculiarity when inoculated upon human beings ? What is actinomycosis ? What are some of the synonyms? To what is it due ? In what two forms does tuberculosis occur in cattle? Is it common among them? How is it related to human tuberculosis? How may it be QUESTIONS TO CHAPTER XIX. 385 transmitted to man ? What precautions should be enforced to prevent this transmission ? What is rabies ? How is it transmitted? Where is the contagium contained? Where does the poison of greatest virulence reside? How may the virus be cultivated, and what changes take place in it ? How may immunity against the disease be produced? Who discovered and advocated this method of inoculation? What is anthrax? What are some of its synonyms? To what is it due? How may it be transmitted? What are the measures of prophylaxis against it, both for man and animals ? What is glanders ? To what is it due ? How may infection occur ? What should be done with animals sick with this disease ? What else should be done ? 25 CHAPTER XX. ANTISEPTICS, DISINFECTANTS, AND DEODORANTS. MUCH confusion exists in the popular mind, and even among physicians, as to the exact meaning of the terms at the head of this chapter. By many they are used synonymously, and hence frequently give rise to ambiguity and misunderstanding. Antisepsis, which is so frequently confounded with disin- fection, should be more accurately defined than is usual by writers. An antiseptic is an agent which retards, prevents, or arrests putrefaction, decay, or fermentation. It does not neces- sarily destroy the vitality of the organisms upon which these processes depend. An antiseptic may also arrest the develop- ment of the organisms which cause infectious diseases, and may hence be used as a preventive of such diseases. But antiseptics do not destroy the life of disease-germs, and hence cannot be relied upon when such organisms are present. By disinfection, in the proper and restricted use of the term, is meant the destruction of the specific infectious material which causes infectious diseases. If the view, is accepted that all in- fectious diseases are due to micro-organisms or germs, then a disinfectant is equivalent to a germicide. In sanitary practice and experimental investigations this view is, in fact, adopted. In testing the action of various disinfecting agents upon infec- tious material, the biological test is the one universally relied upon by experimenters, and no observations upon disinfection based upon chemical tests alone would be accepted by sanitarians as conclusive. It may therefore be assumed for practical pur- poses that no agent can be accepted as a disinfectant if it is not also a germicide. From this it follows that disinfection, to be trustworthy, must be thorough. " There can be no partial disinfection of infectious material ; either its infectious power is destroyed, or it is not. In the latter case there is a failure to disinfect." 1 Obviously, also, there can be no disinfection in the * Report of Committee on Disinfectants of the American Public Health Association^). 236. (387) 388 TEXT-BOOK OF HYGIENE. absence of infectious material. Faecal discharges, a diseased body or corpse, clothing, bedding, an apartment, a ship, or a hospital ward may or may not be infected. In the former case we may speak of disinfecting them ; in the latter, it would be an inappropriate use of the word. Confusion is also liable to arise by considering disinfectants and deodorizers as synonymous. Deodorants merely remove offensive odors, and may not possess any disinfecting power whatever. Thus, one of the most efficient disinfectants at our command (mercuric chloride) is not a deodorizer at all, except by preventing putrefaction. On the other hand, some of the most effective deodorants have only a subordinate position in the scale of disinfectants. Careful investigations have shown that there is a wide divergence between various disinfecting agents in their influence upon disease-germs, some being efficient in high dilutions, while others require to be brought in contact with the germs in great concentration. For example, mercuric chloride will act as an efficient poison to certain disease-germs (anthrax spores) in the proportion of 1 to 1000, while zinc-chloride must be used in the proportion of 1 to 5 (or 20 per cent.). It has been, further, discovered that different disease-germs present varying resisting power to the same disinfecting agent, some being easily destroyed, while others are much more resistant. For example, the following table shows a number of experiments made by Dr. Meade Bolton for the American Committee on Disinfectants : TABLE XXX. ORGANISM. Chloride of Lime. Mercuric Chloride. Carbolic Acid. Typhoid bacillus 1 : 2000 1:10,000 1 :100 Cholera spirillum .... Anthrax spores 1 : 2000 1 : 100 1:10,000 1:1000 1:100 1 :50 Staphylococcus aureus . . . 1 :200 (Uncertain.) 1:100 Staphylococcus citreus 1 :50 1 : 100 Staphylococcus albus . 1 :200 1 :100 ANTISEPTICS, DISINFECTANTS, AND DEODORANTS. 389 Assuming that infectious diseases are caused by micro- organisms, and that these are different from the micro-organisms of ordinary decay or putrefaction, it can be readily understood that the processes of organic decomposition may themselves act as disinfectants. It is known, for example, that when a fer- menting liquid putrefies, the organisms of fermentation disap- pear and give place to the organisms of putrefaction (bacterium termo, etc.). So, likewise, the bacilli of anthrax and of tuber- culosis are killed by the putrefactive process, if this takes place in the absence of free oxygen. Furthermore, the reproduction of organisms of a certain kind ceases when certain chemical (?) changes take place in their environment. Fermentation in a saccharine liquid ceases and the ferment-organisms die when the accumulation of the product of the fermentation (alcohol) has reached a certain proportion, although there may still be un- decomposed sugar present. In like manner it is intelligible that the products of micro-organisms may eventually destroy their producers, and so place a limit to the morbid process. The specific cause of small-pox, yellow fever, cholera, and similar infectious diseases is rapidly destroyed when decomposition of the corpses of those dead with such diseases sets in. Hence, the reason why infectious diseases are not spread from cemeteries. From the foregoing it may be gathered that disinfection consists chiefly in a struggle against organized disease-germs. 1 As, however, experiments and observations have shown that the life-history of disease-germs varies with the different organisms involved, it becomes evident that specific directions concerning disinfection can be given only when the life-history of the specific organism is known. The American Committee on Disinfectants, to whose work reference has already been made, divides disinfectants into two classes : those efficient for the destruction of infectious material containing spores, and those which will destroy infectious ma- terial only in the absence of spores. The recommendations of i Mueller und Falk, in Realencyclopaedie d. ges. Heilk., Bd. IV., p. 62. 390 TEXT-BOOK OF HYGIENE. the committee, covering not only the appropriate disinfectant to be used for the destruction of the organisms, but also the con- ditions under which the agent should be used, are as follow : The most useful agents for the destruction of spore-containing infectious material are : 1. Fire. Complete destruction by burning. 2. Steam under pressure. 105 C. (221 F.) for ten minutes. 3. Boiling in water for half an hour. 4. Chlorinated lime.' 1 A 4-per-cent. solution. 5. Mercuric chloride. A solution of 1 to 500. For the destruction of infectious material which owes its infecting power to the presence of micro-organisms not containing spores, the committee recommends : 1. Fire. Complete destruction by burning. 2. Boiling in water for ten minutes. 3. Dry heat. 110 C. (230 F.) for two hours. 4. Chlorinated lime. 1 A 2-per-cent. solution. 5. Solution of chlorinated soda. 2 A 10-per-cent. solution. 6. Mercuric chloride. A solution of 1 to 2000. 7. Sulphur dioxide. Exposure for twelve hours to an atmosphere containing at least 4 volumes per cent, of this gas in presence of moisture. 3 8. Carbolic acid. A 5-per-cent. solution. 9. Sulphate of copper. A 5-per-cent. solution. 10. Chloride of zinc. A 10-per-cent. solution. The committee would make the following recommendations with reference to the practical application of these agents for disinfecting purposes : FOR EXCRETA. (a) In the sick-room : 1. Chlorinated lime in solution, 4 percent. In the absence of spores : 2. Carbolic acid in solution, 5 per cent. 3. Sulphate of copper in solution, 5 per cent. (6) In privy-vaults : 1. Mercuric chloride in solution, 1 to 500. 4 2. Carbolic acid in solution, 5 per cent. 1 Should contain at least 25 per cent, of available chlorine. 9 Should contain at least 3 per cent, of available chlorine. 1 This will require the combustion of between 1% to 2 kilogrammes of sulphur for every 28 cubic metres of air-space. The vaporization of liquid sulphur-dioxide can be more accurately regulated. 4 The addition of an equal quantity of potassium permanganate as a deodorant, and to give color to the solution, is to be recommended. ANTISEPTICS, DISINFECTANTS, AND DEODORANTS. 391 (c) For the disinfection and deodorization of the surface of masses of organic material in privy-vaults etc.: Chlorinated lime in powder. FOR CLOTHING, BEDDING, ETC. (a) Soiled underclothing, bed-linen, etc.: 1. Destruction by fire, if of little value. 2. Boiling for at least half an hour. 3. Immersion in a solution of mercuric chloride of the strength of 1 to 2000 for four hours. 4. Immersion in a 2-per-cent. solution of carbolic acid for four ' hours. (6) Outer garments of wool or silk, and similar articles, which would be injured by immersion in boiling water or in a disinfecting solution : 1. Exposure in a suitable apparatus to a current of steam for ten minutes. 2. Exposure to dry heat at a temperature of 110 C. (230 F.) for two hours. (c) Mattresses and blankets soiled by the discharges of the sick : 1. Destruction by fire. 2. Exposure to superheated steam (105 C. = 221 F.) for ten minutes. (Mattresses to have the cover removed or freely opened.) 3. Immersion in boiling water for half an hour. FURNITURE AND. ARTICLES OF WOOD, LEATHER, AND PORCELAIN. Washing, several times repeated, with solution of carbolic acid, 2 per cent. FOR THE PERSON. The hands and general surface of the body of attendants of the sick, and of the convalescents, should be washed with 1. Solution of chlorinated soda diluted with nine parts of water (1 to 10). 2. Carbolic acid, 2-per-cent. solution. 3. Mercuric chloride, 1 to 1000. FOR THE DEAD. Envelop the body in a sheet thoroughly saturated with 1. Chlorinated lime in solution, 4 per cent. 2. Mercuric chloride in solution, 1 to 500. 3. Carbolic acid in solution, 5 per cent. 392 TEXT-BOOK OF HYGIENE. FOR THE SICK-ROOM AND HOSPITAL WARDS. (a) While occupied, wash all surfaces with 1. Mercuric chloride in solution, 1 to 1000. 2. Carbolic acid in solution, 2 per cent. (6) When vacated : Fumigate with sulphur dioxide for twelve hours, burning at least 1^ kilogrammes sulphur for every 28 cubic metres of air-space in the room ; then wash all surfaces with one of the above-mentioned disinfecting solutions, and afterward with soap and hot water ; finally throw open doors and windows and ventilate freely. FOR MERCHANDISE AND THE MAILS. The disinfection of merchandise and of the mails will only be required under exceptional circumstances ; free aeration will usually be sufficient. If disinfection seems necessary, fumigation with sulphur dioxide will be the only practicable method of accomplishing it without injury. RAGS. (a) Rags which have been used for wiping away infectious discharges should at once be burned. (6) Rags collected for the paper-makers during the prevalence of an epidemic should be disinfected, before they are compressed in bales, by- 1. Exposure to superheated steam (105 C.= 221 F.) for ten minutes. 2. Immersion in boiling water for half an hour. SHIPS. (a) Infected ships at sea should be washed in every accessible place, and especially localities occupied by the sick, with 1. Solution of mercuric chloride, 1 to 1000. 2. Solution of carbolic acid, 2 per cent. The bilge should be disinfected by the liberal use of a strong solution of mercuric chloride. (b) Upon arrival at a quarantine station, an infected ship should at once be fumigated with sulphurous-acid gas, using 1^ kilogi-ammes of sulphur for every 28 cubic metres of air-space ; the cargo should then be discharged on lighters ; a liberal supply of the concentrated solution of mercuric chloride (1 to 32) should be thrown into the bilge, and at the end of twenty-four hours the bilge-water should be pumped out and replaced with pure sea-water ; this should be repeated. A second fumi- gation after the removal of the cargo is recommended. All accessible ANTISEPTICS, DISINFECTANTS, AND DEODORANTS. 393 surfaces should be washed with one of the disinfecting solutions here- tofore recommended^ and subsequently with soap and hot water. FOR RAILWAY-CARS. The directions given for the disinfection of dwellings, hospital wards, and ships apply as .well to infected railway-cars. The treatment of excreta with a disinfectant before they are scattered along the tracks seems desirable at all times, in view of the fact that they may contain infectious germs. During the prevalence of an epidemic of cholera this is imperative. For this purpose the standard solution of chlorinated lime is recommended. From the foregoing it would appear that heat, chlorinated lime, mercuric chloride, solution of chlorinated soda (Labar- raque's solution), carbolic acid, sulphate of copper, zinc chloride, and sulphur dioxide (sulphur -fumes) are the most generally available disinfectants. The following " general directions " for the practical appli- cation of disinfection are given by the committee : Disinfection of Excreta, etc. The infectious character of the dejec- tions of patients suffering from cholera and t t yphoid fever is well estab- lished ; and this is true of mild cases and of the earliest stages of these diseases, as well as of severe and fatal cases. It is probable that epidemic dysentery, tuberculosis, and perhaps diphtheria, yellow fever, scarlet fever, and t} r phus fever ma}" also be transmitted by means of the alvine discharges of the sick. It is, therefore, of the first importance that these should be disinfected. In cholera, diphtheria, }-ellow fever, and scarlet fever all vomited material should also be looked upon as infectious. And in tuberculosis, diphtheria, scarlet fever, and infectious pneumonia the sputa of the sick should be disinfected or destroyed by fire. It seems advisable, also, to treat the urine of patients sick with an infectious disease with one of the disinfecting solutions below recommended. Chloride of lime, or bleaching powder, is perhaps entitled to the first place for disinfecting excreta, on account of the rapidity of its action. The following standard solution is recommended : Dissolve chloride of lime (chlorinated lime, bleaching powder) of the best quality 1 in pure water in the proportion of 6 ounces to the gallon (45 grammes to the litre). Use 1 quart (1 litre) of this solution for the disinfection of each dis- charge in cholera, typhoid fever, etc. 3 Mix well, and leave in the vessel 1 Good chloride of lime should contain at least 25 per cent, of available chlorine. Recently nascent chlorine for disinfecting purposes has been obtained on a large scale by the electrolysis of sea-water. 3 For a very copious discharge use a larger quantity. 394 TEXT-BOOK OF HYGIENE. for at least one hour before throwing into priv} r -well or water-closet. The same directions appty for the disinfection of vomited matters. Infected sputum should be discharged directly into a cup half full of the solution. 1 A 5-per-cent. solution of carbolic acid may be used instead of the chloride-of-lime solution, the time of exposure to the action of the disinfectant being four hours. Disinfection of the Person. The surface of the body of a sick person or of his attendants, when soiled with infectious discharges, should be at once cleansed with a suitable disinfecting agent. For this purpose, solu- tion of chlorinated soda (liquor sodse chlorinatse Labarraque's solution) diluted with 9 parts of water, or the standard solution of chloride of lime diluted with 3 parts of water, may be used. A 2-per-cent. solution of carbolic acid is also suitable for this purpose, and under proper medical supervision the use of a solution of corrosive sublimate (1 to 1000) is to be recommended. In diseases like small-pox and scarlet fever, in which the infectious agent is given off from the entire surface of the body, occasional ablu- tions with the above-mentioned solution of chlorinated soda are recom- mended. In all infectious diseases the body of the dead should be enveloped in a sheet saturated with the standard solution of chlorinated lime, or with a 5-per-cent. solution of carbolic acid, or a 1 to 500 solution of cor- rosive sublimate. Disinfection of Clothing. Boiling for half an hour will destroy the vitality of all known disease-germs, and there is no better way of dis- infecting clothing or bedding which can be washed than to put it through the ordinary operations of the laundry. No delay should occur, however, between the time of removing soiled clothing from the person or bed of the sick and its immersion in boiling water, or in one of the following solutions until this can be done : Corrosive sublimate, 1 gramme to the litre (1 to 1000), or carbolic acid (pure), 8 grammes to the litre. The articles to be disinfected must be thoroughly soaked with the disinfecting solution and left in it for at least two hours, after which they may be wrung out and sent to the wash. 2 Clothing or bedding which cannot be washed should be disinfected 1 Recently a small spitting-cup made of stiff paper has been introduced especially for the use of consumptives. The cup is carried about by the patient or kept within reach. When the cup has been in use for a time, and before the sputa can become desiccated, it is thrown into the fire and burned. * Solutions of corrosive sublimate should not be placed in metal receptacles, for the salt is decomposed and the mercury precipitated by contact with copper, lead, or tin. A wooden tub or earthen crock is a suitable receptacle for such solutions. ANTISEPTICS, DISINFECTANTS, AND DEODORANTS. 395 by steam in a properly-constructed disinfection chamber. In the absence of a suitable steam disinfecting apparatus, infected clothing and bedding should be burned. Disinfection of the Sick-room. In the sick-room no disinfectant can take the place of free ventilation and cleanliness. It is an axiom in sani- tary science that it is impracticable to disinfect an occupied apartment for the reason that disease-germs are not destroyed by the presence in the atmosphere of any known disinfectant in respirable quantity. Bad odors may be neutralized, but this does not constitute disinfection in the sense in which the term is here used. These bad odors are, for the most part, an indication of want of cleanliness or of proper ventilation, and it is better to turn contaminated air out of the window or up the chimney than to attempt to purify it by the use of volatile chemical agents, such as carbolic acid, chlorine, etc., which are all more or less offensive to the sick, and are useless so far as disinfection properly so called is con- cerned. When an apartment which has been occupied by a person sick with an infectious disease has been vacated, it should be disinfected. The object of disinfection in the sick-room is mainly the destruction of infec- tious material attached to surfaces or deposited as dust upon window- ledges, in crevices, etc. If the room has been properly cleansed and ventilated while still occupied by the sick person, and especially if it was stripped of carpets and unnecessar} r furniture at the outset of his attack, the difficulties of disinfection will be greatly reduced. All surfaces should be thoroughly washed with the standard solu- tion of chloride of lime, diluted with 3 parts of water, or with >1 to 1000 solution of corrosive sublimate. The walls and ceiling, if plastered, should be subsequently treated with a lime-wash. Especial care must be taken to wash away all dust from window-ledges and other places where it may have settled, and thoroughly to cleanse crevices and out- of-the-way places. After this application of the disinfecting solution, and an interval of twenty-four hours or longer for free ventilation, the floors and wood-work should be well scrubbed with soap and hot water, and this should be followed by a second, more prolonged exposure to fresh air, admitted through open doors and windows. As an additional precaution, fumigation with sulphurous-acid gas is to be recommended, especially for rooms which have been occupied by patients with small-pox, scarlet fever, diphtheria, typhus fever and yel- low fever. But fumigation with sulphurous-acid gas alone, as commonly practiced, cannot be relied upon for disinfection of the sick-room and its contents, including bedding, furniture, infected clothing, etc., as is popu- larly believed. 396 TEXT-BOOK OF HYGIENE. When fumigation is practiced, it should precede the general washing with a disinfecting solution heretofore recommended. To insure any results of value, it will be necessary to close the apartment to be disin- fected as completely as possible by stopping up all apertures through which the gas might escape, and to burn not less than 3 pounds of sulphur for each 1000 cubic feet (1^ kilogrammes to 28 cubic metres) of air-space in the room. To secure complete combustion of the sulphur, it should be placed, in the form of powder or small fragments, into a shallow iron pan, which should be set upon a couple of bricks in a tub partly filled with water, to guard against fire. The sulphur should be thoroughly moistened with alcohol before igniting it. 1 Disinfection of Privy-vaults, Cess-pools, etc. When the excreta (not previously disinfected) of patients with cholera or typhoid fever have been thrown into a privy-vault this is infected, and disinfection should be resorted to as soon as the fact is discovered, or whenever there is reasonable suspicion that such is the case. It will be advisable to take the same precautions with reference to privy-vaults into which the ex- creta of yellow fever have been thrown, although we do not definitely know that this is infectious material. For this purpose the standard solution of chloride of lime may be used in quantity proportioned to the amount of material to be disin- fected, but where this is considerable it will scarcely be practicable to sterilize the whole mass. The liberal and repeated use of this solution, or of a 5-per-cent. solution of carbolic acid, will, however, disinfect the surface of the mass, and is especially to be recommended during the epi- demic prevalence of typhoid fever or of cholera. All exposed portions of the vault, and the wood-work above it, should be thoroughly washed down with the disinfecting solution. In- stead of the disinfecting solutions recommended, chloride of lime in powder may be daity scattered over the contents of the privy- vault. Disinfection of Ingesta. It is well established that cholera and typhoid fever are very frequently, and perhaps, usually, transmitted through the medium of infected water or articles of food, and especially milk. Fortunately, we have a simple means at hand for disinfecting such infected fluid. This consists in the application of heat. The boiling temperature maintained for half an hour kills all known disease-germs. So far as the germs of cholera, }'ellow fever, and diphtheria are concerned, there is good reason to believe that a temperature considerably below the boiling-point of water will destroy them. But in order to keep on the safe side, it is best not to trust anything short of the boiling-point (100 C. = 212 F.) when the object is to disinfect food or drink which is 1 Liquid anhydrous sulphur-dioxide may be used, and will probably give better results than combustion of sulphur. ANTISEPTICS, DISINFECTANTS, AND DEODORANTS. 397 open to the suspicion of containing the germs of an}' infectious disease. During the prevalence of an epidemic of cholera it is well to boil all water for drinking purposes. After boiling, the water may be filtered, if neces- sary, to remove sediment, and then cooled with pure ice if desired. The following substances are antiseptics, but in the strength given cannot be depended upon as disinfectants : TABLE XXXI. Thymol, 1:80,000. Bichloride of mercury, 1 : 40,000. Oil of mustard, 1 : 33,000. Acetate of alumina, 1 : 6310. Bromine, . . . . . . . . 1:5597. Picric acid, 1:5000. Iodine, 1:4000. Sulphuric acid, 1:800-1:3353. Permanganate of potassium, . . . . 1 : 3000. Camphor, 1:2500. Eucalyptol, . 1:2500. Chromic acid, . 1:2200. Chloride of aluminum, 1 : 2000. Hydrochloric acid, 1 ' 1700. Benzoic acid, . . . . . . . 1 : 1439. Quinine, . . . . . . -Is 1000. Boric acid, '. 1:200-1:800. Salicylic acid, . . . . . .1:200-1:800. Carbolic acid, 1:500. Sulphate of copper, 1 : 40 - Nitric acid, 1:400. Biborate of soda, 1 : 200. Sulphate of iron, 1 : 2 - Creasote, 1:200. Arsenious acid, 1 : 100- Pyrogallic acid, . 1 : 62. Tr. chloride of iron, 1 : 25. Alcohol, . . . . 40 to 95 per cent. The agents mentioned in the above list may all be used with satisfactory results in surgical and obstetrical practice as antiseptics, but it must be borne in mind that the great danger in treating wounds comes from carrying infectious particles to them in the hands or instruments of the operator. In order to 398 TEXT-BOOK OF HYGIENE. render these aseptic the most thorough measures of disinfection, such as heat, strong chemical disinfectants, and physical as well as chemical and biological cleanliness are indicated. In a sur- gical wound, or in the vagina and uterus of the parturient woman, the use of antiseptics is entirely secondary to disinfec- tion, under which may primarily be understood rigid cleanliness. In public and private sanitation, antiseptics have, as in practical surgery, a subordinate importance. Deodorizers are sometimes useful in sanitary practice, but care must be taken not to look upon deodorization as equiva- lent to disinfection. Among the most useful deodorizers are chloride of zinc, chloride of lime, permanganate of potassium, and a number of the agents mentioned in Table XXXI. [The following additional works are recommended for study in connection with this chapter : Sternberg and Magnin, The Bacteria, 2d ed. Fluegge, Fermente und Mikroparasiten, in von Pettenkofer und Ziemssen's Handb. d. Hygiene, I Th., 2 Abth., 1 Hft. Wernich, Desinfectionslehre zum prak- tischen Gebrauch. Tallin, Traite des Disinfectants etde la Disinfection. Final Report of the Committee on Disinfectants of the American Public Health Association. Sternberg, Disinfection and Personal Prophylaxis Lomb Prize Essay. 1886.] QUESTIONS TO CHAPTER XX. ANTISEPTICS, DISINFECTANTS, AND DEODORANTS. What is an antiseptic ? How may it be used ? Is it necessarily a disinfectant ? Why ? Is a disinfectant an antiseptic ? Why ? Why must disinfection be thorough to be of any value ? What is necessary that there may be disinfection ? How is the term often popularty, but in- r correctly, used ? What is the essential difference between a disinfectant and a de- odonint ? What is a germicide ? What is the true test of the value of a disinfectant ? Have deodorants as such any real sanitary value ? How do disinfectants differ in relation to disease-germs ? How do the latter differ in relation to the former ? How may the products of putrefaction, fermentation, or decay act as disinfectants? How may the products of the disease-germs themselves act as antiseptics or disinfectants? How may disinfectants be classified? What are most useful agents for destroying spore-containing infectious material? How should these be used ? What do we call disinfection by fire or heat ? What agents may be used to disinfect infectious matter not continuing spores ? Which are most efficacious ? What is an essential factor in the successful use of all disinfectants ? In what diseases may the excreta be infected ? What disinfectants may be used for excreta in the sick-room ? In cess-pools ? Why is mercuric chloride not so efficacious here? What is the objection to the use of carbolic acid in typhoid fever? Why is chlorinated lime such a valuable disinfectant ? How much chlorine should it contain ? How should it be prepared ? What is " milk of lime," and what value has it as a disinfectant for excreta ? How may soiled underclothing, bed-linen, etc., be disinfected ? How long should clothing be boiled in order to thoroughly disinfect it? How may clothing that would be harmed by immersion or chemicals be dis- infected ? What will be the effects on clothing of chlorine and sulphur gases? How may mattresses, blankets, etc., be disinfected ? How long should the active process require ? (399) 400 QUESTIONS TO CHAPTER XX. What are some of the best disinfectants for use on the person ? How may the danger of infection from a case of scarlet fever, small-pox, etc., be lessened ? How should the bodies of those dead of infectious dis- eases be cared for ? What can be done in the way of disinfection during the occupancy of the sick-room ? What are the only disinfectants available ? What value will deodorants have here ? What method is to be followed as soon as the sick-room is vacated ? Describe in detail. How may suspected merchandise and the mails be purified ? What treatment should rags, etc., undergo? What is the method prescribed for the disinfection of a ship? For railway -cars ? (See chapter on Quarantine.) How may articles of food and drink be made sterile and safe for use ? How are antiseptics and disinfectants to be used, and for what pur- pose, in surgical and obstetrical practice ? CHAPTER XXL VITAL STATISTICS. (Revised by SENECA EGBERT, A.M., M.D.) THE registration of vital statistics comprises the recording of the births, marriages, deaths, and diseases of a city, State, or nation. The facts thus secured must be properly classified and studied, for in no other way can a knowledge of the health of the inhabitants of such communities be obtained, and a real test is thus also furnished of the actual efficiency of sanitary undertakings. We may, indeed, study disease both by observa- tion and experiment, thus learning that some maladies are more preventable than others and discovering their causes and means of prevention ; and it is also true that for smaller or special communities, such as armies, navies, schools, or special classes of workmen, the health status may be obtained by direct methods ; but for large communities this is clearly impracti- cable, and the sanitarian is obliged to depend upon the census and the above-mentioned registration. The census is the count of its population which every civilized country makes at certain intervals, its returns also including particulars as to age, sex, race, occupation, etc. From the sanitarian's stand-point the age-record is, next to the population, the most important return, for the death-rate varies most according to age. In this country the census now fur- nishes various data for localized " sanitary districts," which may be even smaller than city wards, and these data afford the basis of comparison for variations in different parts of the same city and at different periods. The records of births, marriages, deaths, and diseases are obtained from the registration bureau, having been furnished the latter by duly authorized persons. The duty of registration should devolve upon the sanitary administration, such as the 26 (401) 402 TEXT-BOOK OP HYGIENE. local or State board of health, this being the most appropriate medium for the collection of the information in question, while the individual returns should obviously be made to the bureau by the attending physician in each case. And, as these returns should be as accurate as possible, especially as regards the diag- nosis of preventable diseases and the determination of the causes of death, both primary and secondary, it is one of the reasons why the State should carefully determine the qualifications of the physicians whom it allows to practice within its confines. From a sanitary point of view, the most important object of a registration of vital statistics is to " give warning of the undue increase of disease or death presumed to be due to preventable causes, and to indicate the localities in which sanitary effort is most desirable and most likely to be of use." 1 It should be remembered that the following fundamental principles that underlie all statistical inquiries must be consid- ered in the examination and analysis of any records or reports of the kind in question : 1. The numerical units with which the inquiry has to do must be constant, definite, and precise in character ; if any lack these qualities, such should be omitted altogether. Hence the care that should be observed in the diagnosis of all cases. 2. Groups of the numerical units must be so arranged that no unit is in more than one group at a time, and so that there can be no question as to the group in which each unit belongs. This is comparatively simple where the grouping regards only the age, sex, race, etc., but the difficulty increases with the complexity of facts and requires special talent to properly analyze and develop all possible features. 3. There must be a standard to express the relation of each group to the sum of the individual unit. This is usually 100, 1000, or some multiple of either. 4. The relation of each group to the total units is not a 1 J. S. Billings, " Registration of Vital Statistics," American Journal of the Medical Sci- ences, vol. Ixxxv, p. 37. VITAL STATISTICS. 403 constant one unless all the factors which govern that relation are fixed and invariable, a condition which obviously does not obtain in vital statistics. The limit of variation in the relation of the component groups to the total, in two or more similar series, may, however, be expressed mathematically, and the variation itself will be found to diminish as the sum of in- dividual units increases. Thus, if, in the formula m -f- n q, m be the number of units in one group and n the number in the other, the limit of variation will be indicated by the expres- sion 2-s/?^ 1 ; or, again, the relative value of two or more series is as the square roots of the number of units in the respective series. The arithmetical mean is often used in vital statistics, and this will always approximate the invariable if the number of units is sufficient, but it must be remembered that the relation expressed by the average in one case cannot be predicated posi- tively of any other. As Dr. Guy says, " Averages are numerical expressions of probabilities ; extreme values are expressions of possibilities." The graphic representation of statistical results, examples of which are given on pages 21 to 25 of this volume, is of advantage, since it brings their salient features clearly before the attention of the observer. The numerical units with which we are concerned in vital statistics are persons, either living or dead, and these are di- vided into groups according to age, sex, race, etc. Populations tend naturally to increase, the natural increment being meas- ured by the difference in the number of births and deaths ; but the actual increment depends upon how this is modified by the relation between immigration and emigration. If these factors were all constant, the population would increase in geometrical progression ; but as this is not so, it cannot be exactly deter- mined for periods other than those in which the census is taken. However, in determining the population for years other than census years, it is customary to assume that the same rate 404 TEXT-BOOK OF HYGIENE. of increase continues as prevailed between the last two cen- suses, and to calculate the population therefrom by means of geometrical progression or logarithms. The number of houses in a city will help to determine the approximate population, for the average number of persons to the house in any city remains about the same from year to year. Such counts, as well as police censuses, are, however, almost always too high. In small and slowly-growing districts one-tenth of the difference in population of the last two censuses may be taken for each year since the last census. The population is always counted and annual birth- and death- rates calculated for the middle of the year in this country. REGISTRATION OF BIRTHS. The collection of data for an accurate registration of births is much more difficult than the record of deaths. Instead of requiring physicians and midwives in attendance at the confine- ment to report births, it would be more equitable and probably more effectual to compel the parents, under penalty for failure, to record the birth of each child at the board of health. The items usually included in birth returns are : date and place of birth, sex and color of child, names of father and mother, parents' nativity and age, and father's occupation. Sometimes the residence of the mother, number of children previously borne by the same mother, whether the child is legitimate or not, and various other details are also added. It is evident that for sanitary purposes most of this information is entirely irrele- vant. It seems to the author that, for the purpose of the sani- tarian and medical statistician, the date and place of birth, sex and color of the child, and age, nativity, and occupation of both parents are sufficient. REGISTRATION OF MARRIAGES. The record of marriages is of -no interest to the sanitarian. If, however, the registration could be made by a competent REGISTRATION OF DEATHS. 405 medical man, and the physical condition of the contracting parties noted, valuable deductions might be made in time, espe- cially if the parties themselves and their offspring could be kept under observation for many years. This, however, is so mani- festly impracticable that it barely deserves notice in this place. REGISTRATION OF DISEASES. As has been seen in Chapter XIX, a large class of diseases are communicable from one individual to another, either di- rectly, by contact, or mediately, by infection. In large com- munities it is therefore important that the sanitary authorities should possess information of the presence and prevalence of these diseases, in order that measures may be instituted for their restriction. It is true that in most cases the registration of deaths gives but too mournful evidence of the more fatal of the diseases of this class, but destructive epidemics could probably be frequently averted if preventive measures could be enforced early. Besides, in the case of dengue and epidemic influenza the death-rate may be so small that, if the registration of deaths were alone depended upon, no evidence whatever might be at- tainable of the epidemic prevalence of such diseases. The registration of prevailing diseases is, therefore, one of the most important duties of the registrar of vital statistics. Prompt notice of all cases of infectious, miasmatic, or contagious diseases coming under their professional notice should be re- quired of all physicians. It is unquestionably just, however, that the physicians required to perform this duty should be properly compensated by the public, whose interests they serve. REGISTRATION OF DEATHS. The data entered upon the record of death should comprise the name, age, sex, color, nativity, descent, occupation, and civil condition of decedent, with date, place, and cause of death. Under the heading " Descent " the birthplace of each parent should be given. Occupation should be accurately specified. 406 TEXT-BOOK OP HYGIENE. The place of death should indicate the exact locality (number of street) where it occurred. Both proximate and predisposing causes of death should be entered, and any complications which may have influenced the fatal termination should be noted on the record. This record should be in the possession of the local health authority before a permit for the burial of the deceased is granted. If this is not insisted upon, the report will soon be omitted and the registration become defective. In fact, any system that puts off the collecting and recording of the death returns till the end of the year will fail to register from 25 to 40 per cent, of the number. DEATH-RATE AND BIRTH-RATE. In order to calculate the annual death-rate of a place two facts are required to be known : first, the actual or estimated population (generally obtained, as indicated, from the census), and, second, the number of persons who died in the district during the year. The number of deaths is divided by the pop- ulation, which gives the death-rate for each individual for the year. To find the death-rate per 1000 the rate as found above is multiplied by 1000. Thus, the total number of deaths in the city of Philadelphia during 1893 was 23,655, and the estimated population 1,115.562. The death-rate for the year was 21.20 per 1000, obtained as follows: 23,655 X 1000 - = 21.20 per M. 1,115,562 To calculate the annual death-rate per 1000 of a place from the returns for one week, the weekly population is first ascertained and then the number of deaths for the week divided by the weekly population and the quotient multiplied by 1000. The following example will render this clear : The exact number of weeks in a year is 52.17747. The total population is divided by this number, giving the weekly population. This gives for Philadelphia, assuming the above DEATH-RATE AND BIRTH-RATE. 407 estimate to be correct, a weekly population of 21,381. For the week ending June 3, 1893, the deaths in that city numbered 388. The annual death-rate per 1000, that is to say, the number of deaths in each 1000 of population, if the same rate be maintained throughout the year, is obtained as follows : 388 X 1000 = 18.15 per M. 21,381 The daily death-rate is obtained in a similar manner, the divisor for obtaining the daily population being 365.24226, and the monthly population is found by multiplying the daily population by the number of days in the respective months. But it should be remembered that these rates for such short periods cannot by any means accurately indicate the actual annual rate, and that they are to be used only for comparing the rates for similar periods at different seasons, etc. ; otherwise, with such large populations and such short periods the proba- bilities of error are too great for the results to be of any value. The annual zymotic or infectious death-rate, or that for any one disease, is obtained in the same manner as the general annual death-rate, and likewise the birth-rate. Or, to find the annual death-rate per 1000 of population for this class of dis- eases, the following calculation may be made. Thus, out of the above 388 deaths, 84 were from infectious diseases : 84 X 1000 -- = 3.93 per M. per annum. 21 ,381 Or, if the percentage of deaths from infectious diseases be desired, the procedure would be as follows : - =21.65 per cent, of the total deaths. 388 As an exception to the rule, the rate of infant mortality or infantile death-rate is indicated by the ratio of deaths of chil- dren under one year to the number of births recorded for the year, and is found by multiplying the number of infantile deaths by 1000 and dividing by the number of births; for example, for 408 TEXT-BOOK OF HYGIENE. the year just quoted the decedents under one year of age num- bered 5710; the total number of births for the same year was 30,737. Hence, 5710 X 1000 3Q737 = 185.77 per 1000 births. Nineteen of the 388 deaths for the week ending June 3d were of colored persons. The death-rate of these to the total population is found in a similar manner to the above; but if it is desired to ascertain the death-rate of the colored population alone, the weekly colored population must first be obtained, and the rate calculated from this by the above formula. There are a number of factors that affect the general death- rate, such as the size of the community, habits of life, age- and sex- distribution, occupation of the bulk of the inhabitants, etc. For the country and small towns the rate should be from 9 to 16 per 1000, gradually increasing until for the largest cities it amounts to from 18 to 21 per 1000. Death-rates reported below these figures would indicate that all the deaths had not been recorded, or that the population had been overestimated ; rates above would be evidence that there were special causes at work demanding sanitary investigation and improvement. Among the causes that make the mortality among infants and children high are parents too young or sickly, hereditary taints, unhealthy environments, improper and insufficient food and clothing, and, not rarely, infant life-insurance. It is simply the manifestation of one of the workings of the law of " the survival of the fittest." In localities newly settled, where the proportion of adults to children is greater than the normal, the death-rate is naturally lower ; though it is conceivable that the occupations in which the adults engaged and the vicissitudes and unsettled conditions, both sanitary and social, of a new settlement might cause or tend to cause a very high mortality. Since more males die than females, the sex-distribution will also have its influence on the death-rate, especially if there is a preponderance of one sex over the other in any locality. DEATH-RATE AND BIRTH-RATE. 409 Many conditions affect the death-rate from the different diseases, namely, age, race, sex, occupation, environment, sea- sons, temperature, etc. The zymotic death-rate, and especially that part of it due to typhoid fever, may be an extremely good index of the actual value and benefit of sanitary improvements and the enforcement of hygienic laws. Thus, the mortality from typhoid fever in England and Wales has been reduced more than 50 per cent, since the introduction and enforcement of the general sanitary regulations in that kingdom. On account of the lack of registration of all cases of dis- ease, it is practically impossible to determine the sick-rate of a community or population; but it is said that the sickness of a community amounts to the disablement of one person for two years for every death, and the records of English beneficial societies seem to show that each member averages about one and one-half weeks' sickness annually. The following definitions are introduced because the terms are frequently used in discussions of vital statistics, and especially of life-insurance. The comparative mortality figure indicates that the same number of persons that gave 1000 deaths in the whole population would furnish the deaths indicated by the figure in the city or locality in question. Thus, if the com- parative mortality figure of a place is 925 and the death -rate of the country is 20, there are 1000 deaths for every 50,000 of the whole population and the death-rate of the given place is 18.5. For 20 : 1000 : : x : 925 and x = 18.5. The average or mean age at death is ascertained by adding up the ages of all the decedents and dividing the sum by the number of deaths. Unless it is derived from the life-tables of an entire generation, it is not a fair index of longevity or of sanitary conditions, since it is affected considerably by the age- distribution of the population from -which it is compiled. The expectation of life at any age is the average number of years which persons of that age may expect to live. For the newborn it is the same as the mean duration of life, and, "as 410 TEXT-BOOK OF HYGIENE. applied to communities, it is the mean life-time of a generation of persons traced by the life-table method from birth to death, and is the only true test of the health of populations." A life- table is computed from the number and ages of the living; and of those that die, these factors being obtained from the average population for each age and sex, and from the total death- returns between two or more censuses. It is, as Dr. Farr says, " a barometer which indicates the exact measure of the duration of life under given circumstances, and is indispensable in gauging the influence of sanitary or insanitary conditions." It is only when the population does not vary as to age- or sex- distribution that the mean duration of life is identical with the average age at death. Otherwise, for any person at any age it is the same as the expectation of life. The probable duration of life is equivalent to the age at which any number of newborn children will be reduced one-half, the same conditions persist- ing. With a million children as a basis, it is less than forty- five years for males and about forty-seven years for females. It will be evident, on a little thought, that there must be many sources of error in calculations based upon such uncertain data as are derived from the registration of births and deaths as conducted in most cities in this country. Besides, the subject of vital statistics is essentially abstruse, and requires no little readiness in mathematics to appreciate its profounder bearings. Hence, in the foregoing chapter, no attempt has been made to penetrate beyond the immediate practical aspects of the ques- tions involved. [To those desiring fuller information upon this subject the following works are recommended : Curtis, " Vital Statistics," in Buck's Hygiene and Public Health. Billings, " Registration of Vital Statistics," American Journal of Medical Sciences, vol. Ixxxv. Oldendorff, " Morbilitsets und Mortal! ta?ts-Stutis- tik," ne Realencyclopa?die d. ges. Heilk., Bd. ix. Billings, " Papers on Vital Statistics," Sanitary Engineer, vols. viii and ix. Ibid., Cartwright Lectures on Vital and Medical Statistics, 1890. Wilson, Hand-book of Hygiene and Sanitary Science.] QUESTIONS TO CHAPTER XXI. VITAL STATISTICS. What is comprised in the registration of vital statistics ? How are they to be made of use ? Of what value are the recorded statistics to the sanitarian? How else may disease be studied? Why may not the same methods of determining the general health be applied to large com- munities as to small ones? What is the census ? What returns of interest to the sanitarian does it make? Which of these are the most important? Why? What is the advantage of furnishing returns for " sanitary districts," and what is meant by the latter? What returns are to be obtained from the registration bureau ? Who furnishes these returns ? Who should have charge of the registration ? Why? Why should physicians make the returns? Why should the State take care in the licensing of physicians to practice ? What is the most important object of the registration of vital statistics? What are the fundamental principles underlying all statistical in- quiry ? What units or cases should be omitted ? What renders the classification of groups difficult? What is the usual standard of com- parison ? When is the relation of component groups to the total con- stant? How may the probable limit of variation be determined? What tends to make the arithmetical mean approach the invariable ? How may the relative value of different series of the same kind of cases be deter- mined? What is the difference between averages and- extreme values ? Of what value is the graphic method of representing statistical results? What are the units of vital statistics ? How may they be divided into groups ? What is the natural increment of a population ? How does this differ from the actual increment? If the factors were constant, how would a population increase? Why ? Why cannot the population be determined exactly for intercensal periods ? What is the usual and most accurate way of determining it ? How else may it be esti- mated ? What is the fault of counts made by local authorities or police censuses ? At what time of the year is the count always made ? For what time are annual death-rates, etc., calculated? Why is the collection of data for birth-records difficult ? Who should make the return? What items are usually included in the returns? Which are the only ones of value to the sanitarian and medical statistician ? Why is the record of marriages of no sanitary interest ? llow might it be made so ? Is this practicable ? (411) 412 QUESTIONS TO CHAPTER XXI. What classes of diseases should be reported and recorded ? Why ? What epidemic diseases might escape notice by the statistician if only reported in death-returns ? When should the returns of infectious dis- eases be made? Should there be any recompense for the returns to the physicians ? What data should be given by a death-certificate ? Which items should be accurately specified ? What care should be taken in reporting the cause of death ? When should the burial-permit be issued ? What factors are required in order to calculate the death-rate of a locality ? How is the death-rate for the year obtained ? How may the annual death-rate of a place be calculated from the death-returns for one week ? What is the weekly and the daily population ? How is the monthly population found ? What is the objection to rates determined from returns for such short periods? Of what value are they ? What is meant by the zymotic or infectious death-rate ? How may it be determined? How is the percentage of deaths due to infectious disease determined ? How is the rate of infant mortality determined ? What factors affect the general death-rate ? What is a fair death- rate for small communities ? For large cities ? What do higher rates than this usually indicate ? What do lower ones ? What causes make the mortality so high among infants and young children ? What may make the death-rate of a community lower than the normal? What higher? How may sex-distribution affect the death-rate? What con- ditions or factors affect the mortality from the different diseases ? How may the zymotic death-rate be an index of the value of sanitary measures ? Why is it so difficult to determine the sick-rate of a community ? How may the total amount of sickness be approximately estimated ? What is meant by the comparative mortality figure ? What by the average age at death ? Is this necessarily a fair index of longevitj 7 ? What affects it ? What is meant by the expectation of life ? Of what value is it when applied to communities ? What is a life-table, and how is it computed ? Of what value is it to sanitarians ? When is the mean duration of life identical with the average age at death ? What is meant by the probable duration of life ? Why are calculations of vital statistics liable to be unreliable or inaccurate ? CHAPTER XXII. THE EXAMINATION OF Am, WATER, AND FOOD. (By SKNECA EGBERT, A.M., M.D., Professor of Hygiene, Medico-Chirurgical College, Philadelphia.) OCCASIONS often arise wherein physicians or others desire information concerning the atmosphere of apartments or con- fined spaces, the quality of a drinking-water, or regarding cer- tain articles of food. They have neither time, apparatus, nor, possibly, the peculiar skill necessary to obtain the accurate results of the expert chemist or bacteriologist; nor do they require that the information which they seek should be so extremely exact. What they do wish is to know whether the object in question is sufficiently pure or safe to use from a sanitary point of view, and, if not, wherein it is deficient or harmful. In the preparation of this chapter, therefore, such methods of procedure will be detailed as will serve to determine, with reasonable accuracy and with moderate requirements of time, expense, or technical skill, the hygienic condition of the sub- stances examined. The apparatus and reagents will also be found, for the most part, to be cheap and easily obtainable, and they may often be improvised or prepared from material already at hand. Moreover, a little thought will show how a number of these methods may be developed along the line of greater accuracy, should this be desired, and the principles involved will indicate how similar examinations may be made of other phases of the respective subjects not herein discussed. THE EXAMINATION OF AIR. As has been indicated in Chapter I, the substances in the atmosphere whose proportions or characteristics it may be im- portant to determine are: the aqueous vapor; ozone; suspended (413) 414 TEXT-BOOK OF HYGIENE. particles, both organic and inorganic; living micro-organisms; volatile organic matters, and the various gases given off as products of respiration, combustion, etc., or in the course of certain manufacturing processes. The proportion of aqueous vapor is to be determined by some form of hygrometer, such as Lambrecht's poly meter, or from the readings of wet- and dry- bulb thermometers, which readings, when applied to Glaisher's tables, furnish a means of determining the relative and the absolute humidity, the dew- point, the weight of water to a given volume of air, etc. The presence of ozone in the atmosphere may be demon- strated by exposing to the air strips of white blotting- or filter- paper which have been saturated with a solution of potassium iodide and starch and dried. The ozone, decomposing the potash salt, liberates the iodine and colors the starch blue. During the test the paper should not be exposed to dust, rain, wind, or the direct rays of the sun. Another test (Houzeau's), perhaps even more delicate, is to dampen a strip of faintly-red litmus-paper with a solution of the iodide and dry. The action of ozone upon this is to liberate the alkaline potash and change the litmus to blue. As ammonia is the only other gas likely to produce the same coloration, if another strip of the litmus- paper, not moistened with the salt, be exposed at the same time, whatever difference in shade there may be in the papers is due to the ozone. An idea of the quantity of ozone present may also be gained by comparing the shade of blue given by either test with that produced in similar strips of the starch- or litmus- paper, respectively, which have been exposed to certain definite amounts of ozone, a series of such papers forming a standard of comparison. It may be suggested, for still another test, that a definite quantity of the air to be examined be drawn through a faintly- acid solution of the potassium iodide, phenol phthaleine being used as an indicator. As soon as sufficient alkali is liberated to neutralize the acidity, the pink color of the phenol phthal- THE EXAMINATION OF AIR. 415 eine will be developed and will deepen as the proportion of free alkali increases. Here, also, a control-test to eliminate the influence of ammonia should be made by drawing a similar quantity of air through the same amount of the solution minus the potassium iodide. As before, the difference in color-shading will be proportional to the amount of ozone in the air. Numerous methods have been suggested for the collection of the solid impurities of the atmosphere, varying according to the kind or extent of examination to which they are to be sub- jected. If they are simply to be studied microscopically, glass slides coated with glycerin and exposed to the air, as described on page 37, will be sufficiently covered after several hours, or they may be collected more rapidly by aspirating large quanti- ties of the air against such slides or through tubes coated interiorly with glycerin, as by means of Pouchet's aeroscope or by the apparatus devised by Dr. S. G. Dixon. This latter is especially advantageous where it is desired to collect samples of dust in the air of a number of localities within a short time, and consists essentially of a double cylinder of metal, within which is a rack carrying a number of glycerin- or gelatin- smeared cover-glasses. By an ingenious arrangement the air can be aspirated by means of a hand-bulb over each of these glasses in turn, the dust-particles being deposited on the sticky surface, and thus the samples may be taken from as many localities as there are cover-glasses. Moreover, the specimens may be mounted and examined as they are, may be stained, or, if the glasses be coated with gelatin and the whole apparatus be ster- ilized before the collection, colonies of the bacteria, etc., in the dust may be allowed to develop on the glasses and be studied in, loco under the microscope. Another satisfactory method of collecting suspended par- ticles is to draw a considerable volume of air very slowly through a small quantity of distilled water contained in one or two wash-bottles. The solid particles may then be allowed to settle, and subsequently be removed for microscopical ex- 416 TEXT-BOOK OF HYGIENE. amination by means of a pipette, or the whole may be filtered and the weight of the dust in the aspirated air thus obtained. It might also be well, in the latter case, to evaporate the filtrate to dryness and to determine what proportion of the residue is organic matter, and what is its nature and effects when admin- istered to animals. Lastly, the air may be slowly drawn through a small tube packed with pure sugar, the sugar afterward being dissolved in distilled water, whence the solid particles taken from the air may be removed by means of a pipette or by filtration. The physical nature of the particles of dust thus collected is to be determined by means of the microscope, it being pre- sumed that the examiner is sufficiently familiar with the instru- ment to recognize at sight the more common materials that are apt to pervade the air of occupied apartments, such as bits of cotton, wool, hair, epithelium, etc. Charring on ignition will indicate that the residue is, at least, partly organic, and the odor of burnt feathers that it is nitrogenous and probably of animal origin. Suitable chemical tests will also determine the presence or absence of suspected substances. Thus, an ex- amination of the dust by Marsh's or Reinsch's test may reveal the presence of arsenic, and lead to an investigation as to its source. However, since Cornet and others have demonstrated that the micro-organisms in the air are, in general, closely adherent to the dust-particles, a bacteriological examination of the latter will, except in special cases, be of more importance than a physical or chemical one. To make a qualitative bacteriological examination it is only necessary to coat the glass plates or tubes, already de- scribed, with nutrient gelatin instead of glycerin, and to ster- ilize them before use. They are then exposed to the air as before, covered, and set aside in a place of proper temperature to allow the colonies to develop from the various micro-organ- isms which have adhered to the sticky surfaces; or Dr. Dixon's THE EXAMINATION OF AIR. 417 apparatus, with gelatin-coated glasses, may be used in the manner described. A quantitative bacteriological examination is almost as readily made by drawing a given quantity of air through a sugar- filter, as stated. The tube should not be too large in diameter nor in length, should be tilled with pure granulated sugar and the ends temporarily plugged with cotton, and should, of course, be sterilized, before making the test. After the air has been drawn through it the sugar is carefully emptied into tubes or flasks of nutrient gelatin, which have been heated just enough to melt the gelatin, but not sufficiently high to kill the bacteria, etc., which have been caught in the sugar. The latter rapidly dissolves and leaves the micro-organisms free to develop in the gelatin, which may be poured out before cooling upon steril- ized glass plates or into shallow (Petri) dishes. So-called col- onies rapidly develop from the individual bacteria, and the total number of these colonies may be assumed to represent the number of micro-organisms in the quantity of air aspirated through the filter. Moreover, from these colonies pure cultures may be made and the nature, etc., of their respective microbes determined. To determine the quantity of organic matter in the air the most feasible method is to slowly draw a certain volume of air through a given quantity of twice-distilled ammonia-free water, which retains not only all the volatile and suspended organic matters, but also the gases originating therefrom. The water is then to be tested by the Wanklyn process for " free " and " albuminoid " ammonia, and, if desired, by the Tidy-For- chanirner process for oxidizable organic matter, though it should be noted that in the latter process other gases present in the air, such as sulphuretted hydrogen, may help to decolorize the permanganate solution, and must therefore be excluded or estimated separately. However, as these processes are, perhaps, too complex for the purpose of this chapter, and as it has been shown by de Chaumont and others that the organic matter with which we n 418 TEXT-BOOK OF HYGIENE. are usually most concerned namely, that given off from human bodies as a product of respiration and like processes is pro- duced in quantities proportional to the amount of carbon dioxide eliminated in the same processes, it generally suffices for our purpose to determine the proportion of this gas in the atmos- phere, especially as this determination is much more readily made than the foregoing one. The methods devised by Wolpert and Angus Smith for rapidly estimating the percentage of carbon dioxide have already been given on pages 33-36, but the following modifica- tions of these methods will, it is believed, materially simplify them. Professor Boom has suggested that, instead of the special and somewhat expensive apparatus of Professor Wolpert, a mark be made on any test-tube, say, one inch from the bottom. Fix the bulb of any atomizer to a small glass tube a capillary one, if possible sufficiently long to reach to the bottom of the test-tube, and in such a manner that a definite volume of air is driven from the atomizer-bulb through the tube at each com- pression of the former. In using, fill the test-tube exactly to the mark with a clear, saturated solution of lime-water, and find how many compressions are needed in the out-door air forcing the air through the lime-water each time and taking care not to draw any fluid up into the bulb to make the fluid just turbid enough to obscure a pencil-mark or print on white paper placed beneath the test-tube and viewed from above. Clean the test-tube thoroughly, and repeat the process in the apartment of which the air is to be examined. Assuming that the out-door air contains the normal proportion of carbon dioxide, viz., 0.04 per cent., the percentage in the air of the room is determined as follows : The number of compressions of the bulb in the out-door air : the number of compressions in the room : : x : 0.04 per cent., x representing the percentage of carbon dioxide in the air of the room. THE EXAMINATION OF AIR. 419 As a modification of the Angus Smith method, the author would suggest the following as being, perhaps, more accurate, and as certainly not requiring so much apparatus, etc. : To a wide-mouthed bottle, holding about a quart or litre, fit . a doubly-perforated rubber stopper, one perforation being just large enough to receive the tip of a 1 c. c. pipette, the other carrying a small test-tube, its mouth opening into the jar and close to the inner surface of the stopper. Fill the bottle and test-tube with the air of the room by filling them with water and emptying ; fit in the stopper, and introduce, by means of a 1 c. c. pipette, a cubic centimetre at a time of a standardized alkaline solution, slightly colored with a few drops of a neutral alcoholic solution of phenol phthaleine. Close the pipette per- foration in the stopper with a bit of glass rod and shake the bottle well each time after adding the alkaline solution. Con- tinue in this way until the color is no longer discharged by the acid carbon dioxide of the air. By having the test-tube fitted in the stopper as above and inverting the bottle, the same thickness of fluid is observed each time, and there is more accuracy than if the bottle is used without the test-tube. In either case the fluid should be examined by looking through it against a white light or surface. Now, since the quantity of the alkaline fluid used indi- cates a correspondingly definite amount of carbon dioxide, the number of c. c. of solution used X the volume of CO t each c. c. repretentt X 100 the capacity of the bottle and test-tube in c. c. the number of c. c. of solution used = the percentage of carb.on dioxide in the air examined. A suitable alkaline solution may be prepared by dissolving exactly 4.766 grammes (73.549 grains) of pure anhydrous sodium carbonate in 1 litre (35.238 fluidounces) of distilled water. Each cubic centimetre of this solution is equivalent to a like volume of carbon dioxide. To 10 cubic centimetres of this solution add a few drops of a neutral alcoholic solution of phenol phthaleine and dilute with distilled water to 100 c. c. Each cubic centimetre of the dilute solution will now be neu- 420 TEXT-BOOK OF HYGIENE. tralized by 0.1 c. c. of carbon dioxide, and, if used as suggested, should give close results. The phenol phthaleine is used as an indicator, as it loses its color as soon as the alkalinity of the soda solution is destroyed by the carbonic acid. Example : If 1 1 c. c. of the foregoing dilute solution be used, and the capacity of the bottle and test-tube is 1153 c. c., then 11X0.1X 100 _ 110 115311 ~1142~ 53 '~~ the percentage of carbon dioxide in the air of the apartment. The first (stock) solution must be kept in well-filled and tightly-stoppered bottles, and the dilute solution made up as needed. Pettenkofer's method for determining the percentage of carbon dioxide in the air, which is usually considered the best, is as follows: Into a large, clean bottle or jar, filled with the air of the room as on page 419, introduce 50 c. c. of a clear, satu- rated solution of lime (calcium hydrate), stopper the bottle, and shake it well, so that the air may be well washed by the lime- water. This shaking should be repeated at intervals for several hours, from eight to ten hours being required for the lime-water to absorb all the carbon dioxide in the air in the jar. (How- ever, if baryta barium hydrate water be used instead of the lime-water, the absorption will be completed in an hour.) The strength of the lime- (or baryta-) water being un- known and variable, it is determined by means of an oxalic-acid solution of such strength that 1 c. c. corresponds in acidity to 0.5 c. c. of carbon dioxide. Such a solution is made by dis- solving exactly 2.84 grammes (43.827 grains) of pure crystal- lized oxalic acid, in 1 litre of freshly-distilled water. This acid solution is run into 25 c. c. of the lime-water in a beaker from a graduated burette, or pipette, until the alkalinity of the lime is just neutralized, the neutral point being indicated either by means of a few drops of a neutral phenol-phthaleine solution in the beaker or by turmeric paper, the latter being colored brown, and the phenol phthaleine retaining its color as long as THE EXAMINATION OF AIR. 421 the solution is alkaline. When the lime is exactly neutralized the amount of acid solution used from the burette is noted. Then 25 c. c. of the lime-water from the testing-bottle is meas- ured into a beaker, and its acidity determined in the same manner by means of the oxalic-acid solution. Now, since part of the lime in the solution in the testing-bottle has already been neutralized by the carbonic acid of the air therein, it will require less of the acid solution to neutralize the lime-water from the bottle than it did to neutralize the same quantity from the stock solution, and the difference will indicate the exact amount of carbon dioxide in the air in the testing-bottle. For, though each cubic centimetre of acid solution is equivalent to only one-half cubic centimetre of carbon dioxide, the loss of alkalinity of only half the lime-water in the bottle has been de- termined, and the total loss would be expressed by twice the difference found. The number of cubic centimetres of carbon dioxide in the air in the bottle having been thus determined, and the capacity of the bottle found by measuring the quantity of water it will hold, the percentage of carbon dioxide in the air is readily determined. For example : 25 c. c. of stock lime- water requires 30 c. c. acid solution, and 25 c. c. of lime-water from testing-bottle requires 27 c. c. acid solution ; therefore, 30 27 = 3 c. c., the amount of carbonic acid in the bottle, which contains, say, 2550 c. c. Then 3 X 100 300 _ =012 _ 2550 50 2500 the percentage of carbon dioxide in the room at the current temperature and pressure. It should be noted that the accuracy of all these tests is somewhat vitiated by other acid gases, if present in the air, and due allowance should be made wherever they are suspected. As has been intimated, baryta-water may be used in place of the lime-water, being more rapid in action, but considerably more expensive, than the latter. The solution should be made of the strength of about 7 grammes of crystallized barium 422 TEXT-BOOK OF HYGIENE. hydrate to the litre of distilled water ; it must not be forgotten, also, that it is poisonous when taken internally. A good indi- cator, in addition to the phenol phthaleine and turmeric, is methyl-orange, which is yellow in alkaline and of a reddish tint in acid solutions. The quantity of ammonia in the atmosphere may be de- termined by drawing a certain volume of air through twice- distilled water and then " Nesslerizing " the latter, as in the Wanklyn process of water analysis. So, also, the presence and percentage of other gases, such as nitric, hydrochloric, sulph- urous, and sulphuric acid, sulphuretted hydrogen, ammonium sulphide, etc., are obtained by drawing the air through distilled water and subsequently making the proper chemical tests. For instance, the sulphur gas will darken a solution of lead acetate and ammonium sulphide will change the blue color of nitro- prusside of sodium to violet; consequently, the air may be drawn through standard solutions of these reagents and the resulting coloration compared with that produced by known quantities of the respective gases. As indicated on page 36, the presence of carbon monoxide is shown by the darkening of a solution of palladium chloride or sodio-chloride, but a more delicate test is that of Vogel by means of the spectroscope, which will show the presence of as little as 0.03 per cent, of the gas. In this test a drop of fresh blood is mixed with a little pure water and the mixture well shaken with a sample of the air in a jar. Then a few drops of ammonium sulphide a"re added and the fluid examined spectro- scopically. If carbon monoxide is present the spectrum of oxy- hsemoglobin will be seen, it not having been reduced by the ammonium sulphide ; but if the carbon monoxide is not present, we shall have the spectrum of reduced haemoglobin. As even very small quantities of carbon monoxide in the air are harmful, it will not often be necessary to make a quan- titative test for it; but should this be desired, it can be done by passing a given volume of air several times through a solution THE EXAMINATION OF WATER. 423 of subchloride of copper, which absorbs the carbon gas, and then determining the loss of volume the air has suffered by means of the eudiometer. THE EXAMINATION OF WATER. A number of tests for impurities in water have already been given on pages 74 to 79, but, as these are mainly qualita- tive in character, the author of the present chapter takes the liberty of subjoining the following ones, in "addition, for the benefit of those who may desire a more or less accurate quanti- tative knowledge of the various substances in a water that may affect its purity from a hygienic stand-point. Care should be observed, in collecting samples, that they may fairly represent the water to be examined, and not contain an excess of impurities. Sufficient of the water should be taken for all the tests, say, two or three quarts, at least, and the receptacles must be chemically clean, preferably of glass, and not of tin or metal, and should be thoroughly rinsed several times with the water before being finally filled. The stoppers must also be clean, and should also be tight enough to prevent the escape of gases, as these latter often naturally hold in solu- tion substances which would otherwise go to make the water turbid, and the loss of which by precipitation might possibly change its character. Notes should be made of the time, place, surroundings, etc., when each sample is collected, and as much information as possible obtained of the conditions which may affect the purity of the water. If it is* taken from lakes or reservoirs, the sample should be from some little distance below the surface ; if from hydrants or pumps, the water should be allowed to flow awhile, so that the sample may be from the main source of supply, and not from that which has been standing in the pipe or from storage-tanks. All the tests except those for the turbidity, sediment, nitrogen as ammonia or as organic matter, and for the oxygen-consuming power, should be made with water which has been cleared by sub- 424 TEXT-BOOK OF HYGIENE. sidence or filtration ; those mentioned should be made with the sample as taken from the source of supply. As indicated in Chapter II, the tests for color, turbidity, etc., are made by comparing the sample with an equal volume of distilled water, using tall, glass jars of the same calibre, and looking down through equal depths upon a white surface. Or the turbidity may be indicated by noting the depth which is required to obscure print from type of a certain size or font. The smell may be detected by heating the water to from 40 to 60 C. (104 to 140 F.) in a glass-stoppered bottle. Sometimes the higher temperature is needed to liberate odorous gases that would otherwise be undetected, and, again, there is often no smell at all from a very bad water or from one from an obnoxious source. The test, therefore, may or may not indicate sewage or faecal contamination. The impurities that give any perceptible taste to water, except when in large amounts, are very few in number, and many waters dangerously polluted have a good and pleasing taste. Of the metals, iron is the only one which is perceptible to the taste in small quantities ; but one-fourth of a grain of this base to the gallon may thus indicate its presence. Caution should, of course, be observed in tasting waters suspected of containing infectious or poisonous matters. The proportion of air or gas a water contains is indicated, in a measure, by its lustre and by the presence of bubbles on the sides and bottom of the vessel, though the number of the latter is also affected by the. temperature. Test for Chlorine. Solutions required: 1. Standard silver-nitrate solution. To 1 litre of pure distilled water add 4.788 grammes of pure silver nitrate (AgNO 3 ). One cubic centimetre of this solution is equivalent to 1 milligramme of chlorine. 2. Potassium-chromate solution. A 10-per-cent. solution of potassium chromate (K 2 CrO 4 ) in distilled water free from chlorine. Process: To 100 c. c. of the water to be tested add a few THE EXAMINATION OF WATER. 425 drops of the potassium-chromate solution, and then run in the silver-nitrate solution from a graduated burette, adding it drop by drop and stirring the water continually with a glass rod. Continue until a faint but permanent orange-red tint has been produced, showing that all the chlorine has combined with the silver, the persisting reddish tint being due to silver chromate. The number of cubic centimetres of silver-nitrate solution used indicate the number of milligrammes of chlorine in 100 c. c. of the water, or the parts per 100,000 ; this multiplied by 10 gives the number of milligrammes of chlorine in 1 litre, or parts per million. If the water contain but little chlorine, the test will be more accurate if 250 c. c. of the water be first evaporated over a water-bath to about 50 c. c. before proceeding as above: four times the result will then give the number of milli- grammes of chlorine in 1 litre. Should it be desired to express the proportion in terms of sodium chloride, multiply the result, obtained as above, by 1.648; or make up the silver-nitrate solu- tion by adding 2.905 grammes to the litre, each cubic centimetre of this solution being then equal to 1 milligramme of sodium chloride. Test for Nitrates. Solutions required : 1. Phenol-sul phonic acid. To 37 c. c. of strong sulphuric acid add 6 grammes of pure carbolic acid and 3 c. c. of distilled water. 2. Standard potassium-nitrate solution. Add 0.722 gramme of fused potas- sium nitrate (KNO 3 ) to 1 litre of distilled water. Each cubic centimetre of this contains T ^ milligramme of nitrogen. The water used in making these solutions must be free from nitrates. Process: Evaporate 10 c. c. of the water to be tested (or 25 c. c. if it is presumably low in nitrates) just to dryness. This is best done over a water-bath. Add 1 c. c. of phenol- sulphonic acid, stir with a glass rod, add 1 c. c. of distilled water and 3 drops of strong sulphuric acid ; warm the dish, add about 25 c. c. of distilled water, then ammonia to excess, and dilute with distilled water to exactly 100 c. c. Treat 1 c. c. of the standard potassium-nitrate solution in exactly the same 426 TEXT-BOOK OF HYGIENE. manner and compare the tints produced. Dilute the darker of the two with distilled water until the tints match exactly, and calculate the amount of nitrogen present as nitrates in the water being examined from the amount of dilution necessary. Example : The tint from the 1 c. c. of standard potassium- nitrate solution is the darker and needs an addition of 25 c. c. more water before it matches the other. Therefore, 125 : 100 : : 0.1 : x = 0.08, the number of milligrammes of nitrogen existing as nitrates in the 10 c. c. of water tested. The test depends upon the conversion of the phenol-sulphonic acid into picric acid by the nitrates and the subsequent formation of ammonium picrate, which gives a yellow tint to the water. The amount of picric acid and picrate formed is exactly propor- tional to the quantity of nitrates present. Test for Nitrites. Solutions required: 1. Sulphanilic acid. Dissolve 0.5 gramme of sulphanilic acid in 150 c. c. of dilute acetic acid (sp. gr. 104). 2. Naphthylamine acetate. Boil 0.1 gramme of solid naphthylamine in 20 c. c. of distilled Avater, filter through a plug of washed absorbent cotton and mix the filtrate with 180 c. c. of dilute acetic acid. 3. Standard sodium- nitrite solution. Dissolve 0.275 gramme of pure silver nitrite in pure water, add a dilute solution of pure sodium chloride till precipitate ceases to form and dilute to 250 c. c. with pure water. For use, dilute 10 c. c. of this solution to 100 c. c., each cubic centimetre of the latter dilute solution containing 0.01 milli- gramme of nitrogen. Keep the stronger solution in the dark when not in use, and make up the dilute solution anew each time. All water used in these solutions must be free from nitrites ; likewise all water used for dilution in the test. Process : Measure 25 c. c. of the water to be examined into a Nessler tube or large test-tube, add 2 c. c. each of the sulphan- ilic acid and naphthylamine-acetate solutions, using a separate pipette for each. In a similar tube dilute 1 c. c. of the standard sodium-nitrite solution (dilute) to 25 c. c. witli nitrite-free dis- tilled water, and add the same quantity of the above reagents to THE EXAMINATION OF WATER. 427 it. Compare the colors at the end of five minutes, and esti- mate the amount of nitrites by diluting the darker solution till it matches the lighter, just as was done in testing for nitrates. The foregoing test is a very delicate one, and gives the quantity of nitrogen present as nitrites, which should not be over a trace. Test for Free and Albuminoid Ammonia. Wanklyn's Method. Solutions required : 1. Standard ammonium-chloride solution. Dissolve 0.382 gramme pure dry ammonium chloride (NH 4 C1) in 100 c. c. ammonia- free water. Each cubic centi- metre of the dilute solution contains 0.01 milligramme of nitrogen. 2. Alkaline potassium-permanganate solution. Dis- solve 200 grammes of potassium hydrate (KI1O) in sticks, and 8 grammes of potassium permanganate in 1 litre of distilled water. Evaporate to about 750 c. c. to drive off any ammonia present, and make up to 1 litre again with ammonia-free water. To make ammonia-free water, add about 1 grain sodium carbonate to the litre of distilled water, and boil till about one-fourth is evaporated. 3. Nessler's reagent. Dissolve 35 grammes potassium iodide (KI) in 100 c. c. of distilled water, and 17 grammes mercuric chloride (IIgCl 2 ) in 300 c. c. of water; add the mercuric-chloride solution to the potassium iodide until a permanent precipitate is formed. Then dilute with a 20-per-cent. solution of sodium hydrate (NallO) to 1000 c. c. ; add mercuric-chloride solution till a permanent precipitate again forms, and allow to stand until clear. This reagent gives a brown or yellowish-brown coloration if ammonia .be present in water, and improves on keeping. Process : Place 500 c. c. of the water to be examined in a retort, connect with a condenser, and boil gently so that the water may distil over slowly. The retort and condenser should have been thoroughly rinsed with ammonia-free water. Collect the distillate, 50 c. c. at a time, in Ncssler tubes, add 2 c. c. of Nessler's reagent to each 50 c. c. and determine the amount of ammonia or nitrogen in each, as follows : Place in another Nessler tube 50 c. c. ammonia-free water and 2 c. c. Nessler's 428 TEXT-BOOK OF HYGIENE. reagent ; run in from a burette the standard ammonium-chloride solution until the color exactly matches that of the first 50 c. c. of the distillate. Repeat the process with each 50 c. c. of dis- tillate until the test shows that no more ammonia is coming over from the retort. The total amount of ammonium-chloride solution used indicates the ^total amount of nitrogen of the free ammonia. Usually all the free ammonia will come over in the first 150 c. c. or 200 c. c. of distillate. Compare the colors by looking down through the tube upon a white surface. If the first 50 c. c. give a precipitate with the Nessler reagent, it must be diluted and the amount of nitrogen estimated from the diluted distillate. The free ammonia being all determined, allow the retort to cool and add to the water remaining in it 50 c. c. of the alkaline-permanganate solution. This converts a certain proportion of the nitrogenous organic matter into am- monia. Distil as before, estimating the amount of nitrogen in each 50 c. c. of the distillate, until no more ammonia comes over. The amount of ammonium-chloride solution thus used will indicate the nitrogen of albuminoid ammonia ; and the total amount of ammonium-chloride solution used in the whole process gives the nitrogen of the/?*ee and albuminoid ammonia in the 500 c. c. of water. Tests for Hardness. Solutions required : 1. Soap solution. Dissolve about 10 grammes of Castile or soft soap in 1 litre of weak (35 per cent.) alcohol. 2. Standard lime solution. Dis- solve 1.11 grammes pure calcium chloride in 1 litre of distilled water. One c. c. of this solution is equivalent to 1 m. g. of calcium carbonate (CaCO 3 ). Process : First, find how much of the soap solution is needed to make a lather with 100 c. c. of distilled water, as follows : Place the water in a flask holding about 250 c. c. and run in the soap solution from a burette, a few drops at a time, corking and shaking the flask well after each addition. The lather should have a depth of about one- fourth of an inch, and should be permanent for at least five minutes. Then standardize the soap solution by diluting 5 c. c. THE EXAMINATION OF WATER. 429 of the standard lime solution to 100 c. c. with distilled water and finding how many cubic centimetres of the soap solution are necessary to make a permanent lather with it. This quantity, less the number of cubic centimetres needed to make a lather with the 100 c. c. of distilled water, represents the amount of soap solution that will neutralize 5 m. g. of cal- cium carbonate or its equivalent. Lastly, determine in the same way the number of cubic centimetres of soap solution necessary to make a permanent lather with 100 c. c. of the water to be examined; subtract the quantity necessary for 100 c. c. distilled water and estimate the amount of calcium carbon- ate or its equivalents present, as follows : For example, it takes 2 c. c. of soap solution to make a lather with the distilled water and 12 c. c. with the diluted lime solution. Then, 12 2 10 c. c. 5 m. g. calcium carbonate, and each cubic centimetre of the soap solution 0.5 c. c. of the standard lime solution, or 0.5 m. g. calcium carbonate. Consequently, if 100 c. c. of the water examined require 17 c. c. of soap solution, it must contain (17 2) X 0.5 7.5 m. g. calcium carbonate or its equivalent, and 1 litre of the water contains 75 m. g. calcium carbonate. Testa for Lead, Copper, and Iron. To 50 or 100 c. c. of the water in a white porcelain dish, or in a tall glass jar, over white paper, add a few drops of ammonium sulphide, (NH 4 ) 2 S. A dark coloration or precipitate indicates the presence of either lead, copper, or iron, due to the formation of the respective sulphide. Then add a few drops of hydrochloric acid (HC1). If the color disappear, iron only is present ; if it persist, lead or copper is present. In the latter case, add a few drops of acetic acid and about 1 c. c. of a strong solution of pure potas- sium cyanide. If the color disappear, it is due to copper ; if it remain, lead is present. If lead only is present in the water, the above test will detect T V grain per gallon. The above test may be corroborated as follows : Partly fill two test-tubes with the original water ; to one add a little potassium-chromate solu- 430 TEXT-BOOK OF HYGIENE. tion ; an opacity and the deepening of the color to a canary yellow indicates lead. To the second add a drop of dilute hydrochloric acid and a few drops of -potassium-ferrocyanide solution ; a blue color indicates iron, either ferrous or ferric ; a bronze or a mahogany-red color indicates copper. Quantitative tests for the above metals may be made by making standard solutions of the respective elements, treating a measured quan- tity of the original water with the proper reagent, as indicated, and comparing the color produced with that given by a definite quantity of the respective standard solution. Test for Phosphates. Solution required, ammonium molyb- date: Dissolve 10 grammes of molybdic anhydride in 41.7 c. c. of ammonia (NH 4 HO), sp. gr. 0.96, and pour slowly into 125 c. c. of nitric acid (HNO 3 ), sp. gr. 1.20 ; allow to stand in a warm place for several days till clear. Process : Slightly acidify 500 c. c. of the water with nitric acid, evaporate to about 50 c. c., add a few drops of ferric chloride (Fe 2 Cl 6 ) and ammonia in slight excess. Filter, dissolve the precipitate in the smallest possible quantity of nitric acid, and evaporate to 5 c. c. Heat nearly to boiling ; add 2 c. c. of ammonium-molybdate solu- tion ; keep solution warm for one-half hour. If there is an appreciable quantity of precipitate, collect it on a small, weighed filter-paper, wash with distilled water, dry at 100 F., and weigh. The weight of the precipitate multiplied by 0.05 gives the amount of phosphates as PO 4 in the 500 c. c. of water. In the bacteriological examination of water, 1 c. c., or a definite fractional part thereof, of the water is to be added to a little sterilized nutrient gelatin, heated just enough to liquefy it, the whole shaken to thoroughly mix it, and then cooled in an even film on the interior of the test-tube (Esmarch's roll-cult- ure) or poured out upon sterilized glass plates or into Petri dishes. Or, as Prof. Leffmann suggests, fiat, rectangular bottles, of 8 or 10 ounces' capacity, may be used instead of test-tubes. Sufficient nutrient gelatin is placed in eacli to cover one of the flat sides with a thin film, and the bottle stoppered and steril- THE EXAMINATION OF FOOD. 431 ized. Then, when needed, the gelatin is gently melted, the measured quantity of water introduced and mixed with the gelatin, and the bottle placed on its side until the gelatin cools. Within a short time colonies develop from the micro-organisms thus fixed in the gelatin, and from these colonies pure cultures may be made of the respective species, and further experiments and study carried on. It must always be remembered that, in collecting samples of water for bacteriological examination, great care must be ob- served to avoid accidental contamination of the culture-media, etc., by extraneous organisms. Where possible, the inoculations should be made at the place where the samples of water are col- lected, the water being taken up by means of sterilized pipettes and measured at once into the sterilized gelatin tubes or bottles. If this cannot be done, the water should be collected in well- sterilized, glas's-stoppered bottles. These should be washed externally, submerged, unstoppered, filled and restoppered, all below the surface, and then transferred to the laboratory and the inoculations made as soon as possible, packing them in ice if the distance be great or there is any cause for delay, in order to prevent the too rapid multiplication of certain of the organ- isms and the disappearance of others. THE EXAMINATION OF FOOD. It would be manifestly inadvisable to attempt to detail, within the limits of this chapter, the methods for the determina- tion of the purity and healthfulness of the many articles of food that make up the daily dietaries of the people at large ; but since occasions are constantly arising when it is desirable to know something of the condition of certain food-stuffs which are used by practically every one, and which are especially liable to sophistication or adulteration, the following notes are, there- fore, added as being within the scope of the chapter : MILK. Good milk should be ivory-white in color, opaque, of neutral or slightly-alkaline reaction, and should have no 432 TEXT-BOOK OF HYGIENE. sediment nor any unusual taste or odor. The specific gravity should be 1029 or above; the proportion of cream, from 10 to 40 per cent, by volume ; the fats, 3 per cent, or more, and the total solids 12.5 per cent, or more. The color is enriched by a high percentage of cream, but too rich a color or one with a reddish or yellowish tint may in- dicate the addition of annatto. A poor color indicates that the milk is deficient in fat, and may be due to skimming or water- ing, or both, but a peculiar blue color is sometimes produced by the growth of a certain fungus in the milk. The lessening of fat also tends to make the milk translucent and less opaque. An acid reaction, unless very slight, indicates " souring " of the milk or the addition of some preservative, such as saly- cylic or boric acid ; while a strongly-alkaline reaction points to the addition of some substance like chalk, sodium carbonate, etc., to increase the specific gravity. Such addition is verified by a high percentage of total solids and by the effervescence of the latter upon the addition of a drop or two of hydrochloric acid. The specific gravity is determined by means of the lactom- eter, in using which corrections must be made for the tempera- ture if the latter varies much from 60 F., the standard. The specific gravity is slightly raised by skimming the milk, since the cream is lighter than the whole milk, and, theoretically, a very high percentage of cream tends to lower the specific gravity ; but, in reality, a milk rich in cream is also rich in other solids that keep the specific gravity high or, at least, normal. The percentage of cream is determined by the creamome- ter (see page. 101), which should be covered and in which the milk should stand for eight or ten hours. The principal sophistications of milk are by watering, skim- ming, the addition of solids to increase the specific gravity or to act as preservatives or to mask " souring," and the addition of annatto and the like to enrich the color. Watering is indicated THE EXAMINATION OF FOOD. 433 by a low specific gravity and by a low percentage of cream and of total solids. Skimming is indicated by a low percentage of cream and poor color, though the latter may be disguised by the addition of annatto, etc. The specific gravity will be very slightly raised by the skimming, but if the milk has been both skimmed and watered the density will be lowered. To Determine the Percentage of Total Solids. Weigh a small evaporating-dish, preferably platinum. Add 5 or 10 c. c. of milk, and weigh the dish and milk to get the weight of milk. Evaporate to dry ness over a water-bath, completing the drying in a water-oven until there is no further loss of weight. Weigh the dish and contents (total solids) ; subtract the weight of dish and divide by the weight of milk. The result is the percentage of total solids. To Determine the Percentage of Ash. Ignite the total solids over the naked flame until all black specks have disap- peared. Cool and weigh. Divide the weight of ash by weight of milk. The result is 'the percentage of ash. To Determine the Percentage of Fats. Proceed as above with 10 c. c. of milk and evaporate till the residue is a tena- cious pulp. Extinguish the flame, fill the dish half-full of ether, and stir and pound the residue thoroughly with a glass rod ; filter through a small filter-paper, reserving the filtrate ; add more ether to the residue, stir as before and filter, repeating the process three times, or till the residue is perfectly white. Wash filter-paper well with ether, and evaporate all the ether to dryness. Weigh the residue (the fat) and divide by the weight of milk. Result : percentage of fats. Test for Annatto. A percentage of cream considerably lower than the color of ntilk would indicate justifies the sus- picion that some coloring matter has been used. This is gen- erally annatto. Coagulate one ounce of milk with a few drops of acetic acid, and heat ; strain and press out excess of liquid from curd. Triturate the curd in a mortar or dish with ether. Decant the ether and add to it 10 c. c. of a 1-per-cent. solution 434 TEXT-BOOK OF HYGIENE. of caustic soda. Shake and allow to separate ; pour off the upper layer into a porcelain dish. Put in two small discs or strips of filter-paper. Evaporate gently ; annatto will dye the discs an orange or buff color. Moisten one disc with dilute sodium carbonate to fix the color. Touch the other disc with a drop of stannous chloride ; annatto will give a rich pink color. This test is sensitive to 1 part of annatto in 1000 of milk, and with milk in any condition. Test for Boric Acid. In igniting the total solids, boric acid, or boron, gives a greenish tinge to flame. Place in a porcelain dish one drop of milk, two drops of strong hydrochloric acid, and two of a saturated tincture of tumeric. Dry on a water- bath, remove as soon as dry, cool and add one drop of ammo- nia on a glass rod. A slaty-blue color, changing to green, is given if borax is present. This test will show -j-oV'o grain of borax. Less will give the green color, but not the blue. BUTTER. Good butter should have a good taste, odor, and color; it should not be rancid, and should not contain too much water or salt, nor should it have any added coloring matter. The average composition should be about as follows : Fat, 82 per cent. ; casein, 2 per cent, (not over 3 per cent.); ash or salts, 2 per cent.; water, 13 per cent.; milk-sugar, 1 per cent. Butter-fat is a compound of a glycerin with certain fatty acids, some of them volatile and soluble in hot water, others non- volatile and insoluble in hot water. Oleo-margarine consists of ordinary animal (or vegetable) fats melted, strained, cooled with ice, worked up with milk, col- ored, and salted. These fats are usually beef or mutton, lard or cotton-seed, palm- or cocoa-nut- oil. If care and cleanliness are observed in the manufacture, oleomargarine is not harmful or innutritions, but it should not be sold as butter. Fraud is to be detected by observing the difference in composition and properties of the fats. The following table, from Kenwood's " Hygienic Laboratory," will show the char- acteristic difference in the fats : THE EXAMINATION OF FOOD. 435- BUTTEB-FAT. 1 . The specific gravity is very rarely be- low 910, never below 909.8. 2. The soluble, volatile fatty acids aver- age between 6 and 7 per cent., never below 4.5 per cent. 3. The insoluble fatty acids form about 88 per cent, of the total weight of butter- fat. 4. The melting-point of the fat varies from 86 to 94 F. ; is usually from 88 to 90 F. 5. Is readily and completely soluble in ether. 6. Under the microscope pure butter consists of a collection of small oil-glob- ules with an occasional large one. No crystals, except when the fat has been melted. BEEF-FAT, ETC. Is never above 904.5. Rarely more than % per cent. ; never above % per cent. Generally about 95 per cent. Rarely, if ever, above 82 F. Less so, and leaves a residue. The contours of the small oil-globules are less distinct, and the larger ones are more numerous and irregular in size. Crystals of the non-volatile acids are often seen. To Determine the Specific Gravity. Melt a quantity of the butter in a beaker on a water-bath at about 150 F. After a time, when the fat is perfectly clear and transparent, carefully de- cant from the lower stratum of water, curd and salt on to a fine filter ; collect the filtrate and pour into a specific-gravity bottle, which has been previously weighed, both when empty and when filled with distilled water at 100 F. See that the bottle is exactly full of the fat ; wipe clean and weigh when the tempera- ture is as near 100 F. as possible, because solidification soon begins below this temperature. Subtract the weight of the bottle, divide by the weight of the water, and multiply by 1000. The result is the specific gravity. To Find the Melting- Point. Pour a little melted fat into a small test-tube (2" x J"). Partly fill two beakers of unequal size with cold water ; place the test-tube in the smaller (taking care to allow no water to mix with the fat), and the smaller in the larger, and gently heat the outer beaker. Suspend a ther- mometer in the smaller, near the test-tube, and note the temper- ature when the fat begins to melt. This is the melting-point. To Determine the Percentage of Insoluble (Non- Volatile) Fatty Acids. To 5 grammes of butter-fat add 50 c. c. of alcohol 436 TEXT-BOOK OF HYGIENE. containing 2 grammes of caustic potash (KHO) and boil gently for fifteen or twenty minutes to saponify the fat. Dissolve the soaps thus formed in 150 to 200 c. c. of water and decompose with about 25 c. c. of dilute hydrochloric acid. The separated fatty acids are collected upon a weighed filter-paper, washed with 2 litres of boiling water, dried at 95 to 98 C., and then weighed. The weight of these insoluble fatty acids should not be over 90 per cent, of the weight of the butter-fat. FLOUR AND BREAD. Wheat-flour should be almost but not perfectly white, also smooth and free from grit ; it should have no moldy or unpleasant odor, and, unless made by the new process, should be cohesive when lightly compressed in the hand. There should be no signs of parasites or fungi under the microscope. The proportion of gluten should be more than 8 per cent. ; of water, less than 18 per cent., and of ash, less than 2 per cent. To Determine the Percentage of Water and Ash. In a weighed platinum (or porcelain) dish place about 50 grammes of flour, weigh and dry over a water-bath for an hour or so ; then complete the evaporation in a water-oven until there is no further loss of weight ; weigh, subtract this weight less the weight of the dish from the original weight of the flour ; divide the remainder, the weight of the water, by the original weight of the flour. The result is the percentage of water. Then ignite the dried flour in the dish and incinerate till there are no longer any black particles and only the ash remains ; cool, weigh, and divide by the original weight of the flour. The result is the percentage of ash. To Determine the Percentage of Gluten. By means of a glass rod, mix a weighed quantity of flour with a little distilled water into a stiff dough ; then repeatedly wash away the starch and soluble constituents, kneading the dough with the rod or fingers and continuing until the wash-water conjes away clear ; the gluten and a small amount of fat and salts remain. Spread out on a weighed dish or crucible-lid, dry in a water-oven, and THE EXAMINATION OF FOOD. 437 weigh ; divide by the original weight of the flour. The result is the approximate percentage of gluten. The gluten should pull out into long threads, otherwise it is poor. An excess of water impairs the keeping-quality and lessens the amount of nutriment in the flour. An excess of ash indi- cates the addition of mineral substances. A deficiency of gluten indicates that the flour is not pure wheat-flour. Parasites and fungi especially affect or live in old or damp and inferior flour. To Test for Mineral Substances. Shake a little flour in a test-tube with some chloroform, and allow it to stand for a few moments. The flour floats and any mineral matter sinks to the bottom, when it can be removed with a pipette and examined under a microscope. Wheat-bread should be fairly dry, light, and spongy ; clean and nearly white ; of pleasant taste ; not sodden, acid, or musty ; no parasites or moldiness. It should contain no flour other than wheat; but little, if any, alum ; no copper sulphate ; and should not yield over 3 per cent, of ash. Test for Alum. Add 5 c. c. of a 5-per-cent. tincture of logwood and 5 c. c. of a 1 5-per-cent. solution of ammonium carbonate to 25 c. c. of water ; soak a crumb of the bread in this for a few minutes ; drain and gently dry. Alum is indi- cated by a violet or lavender color, its absence by a dirty-brown color on drying. Test for Copper Sulphate. Draw a glass rod dipped in a solution of potassium ferrocyanide across a cut slice of the bread ; copper is indicated by a streak of brownish-red color. Test for Ergot in Flour or Bread. Add liquor potassse ; a distinct, herring-like odor (due to propylamine) is appreciable if ergot be present. An excess of water, an unnatural whiteness, and a low percentage of ash in bread indicate the addition of rice. Pota- toes give an increased percentage of water and an alkaline ash. 438 TEXT-BOOK OF HYGIENE. [The following works are recommended to those desiring fuller details of the foregoing methods, or for the further ex- amination of these subjects : Kenwood's Hygienic Laboratory. Examination of Water for San- itary and Technical Purposes, by Leffmann and Beam. Sanitary Exam- inations of Air, Water, and Food, by Fox. Parkes's Practical Hygiene. Practical Hygiene, by Coplin and Bevan.] QUESTIONS TO CHAPTER XXII. THE EXAMINATION OF AIR, WATER, AND FOOD. Of what substances in the atmosphere may it be necessary at times to obtain the proportion ? How is the proportion of aqueous vapor to be determined ? What causes the difference in the readings of the wet- and dry- bulb thermometers, and what tables are to be used in conjunc- tion with them ? How may the presence of ozone in the air be demonstrated ? Upon what does the test depend? How might an approximate quantitative test of ozone be made ? How may the suspended impurities in the atmosphere be collected for examination ? Which method requires the least apparatus, etc. ? How may the character and nature of the suspended particles be de- termined ? How may a quantitative bacteriological examination be made? What are some of the advantages of Dr. Dixon's apparatus? Of the sugar-filter method? How may pure cultures of micro-organisms in the air be obtained ? How may the quantity of organic matter in the air be determined ? Why do we determine the proportion of carbon dioxide in the air? What is Wolpert's method for finding the percentage of this gas, and how may this method be simplified ? Upon what does this test depend ? What precautions must be observed in making the test? What is the Angus Smith method for determining the proportion of carbon dioxide? How may it be improved? What is the use of the phenol phthaleine in the solution ? How is the percentage of carbon dioxide calculated ? How is the alkaline solution to be prepared? Upon what does Pettenkofer's method depend? What apparatus and reagents are required? Why must the lime-water be standardized each time? What is the value of the oxalic-acid solution? What are some good indicators to use in this test ? Why is just twice the volume of lime-water introduced into the bottle that is afterward taken from it and tested ? What are some of the advantages and disa'd vantages of baryta-water in comparison with lime-water? How may the quantity of ammonia in the atmosphere be determined ? How may the presence of other gases be shown ? What is the usual test for carbon monoxide? Upon what is Yogel's test based? Is it a deli- cate one ? Why is it usually not necessary to make a quantitative ex- amination of the carbon monoxide? What care should be observed in the collection of water for ex- amination? How much will be necessary for the customary tests? What notes should be made at the time of collection? What tests require the previous clearing of the water? How are the tests for color and turbidity made? For smell? What indicates (439) 440 QUESTIONS TO CHAPTER XXII. the degree of aeration? What metallic impurities may give a taste to the water ? What information as to the source or purity of a water may sometimes be given by the smell ? What are the solutions needed in the quantitative test for chlorine ? What is the strength of each, and what is the relation of the silver- nitrate solution to chlorine? What is the use of the potassium-chroniate solution? How may the result be expressed? What solutions are used in testing for nitrates quantitatively? Upon what does this test de- pend? What does the depth of color indicate? What precautions must be observed in testing for nitrites ? Is the test a delicate one? In the test for free and albuminoid ammonia, what is the function of the ammonium-chloride solution? Of the potassium-permanganate solution? What part of the distillate contains most of the free am- monia? When is it evident that the water contains no more ammonia? In testing for hardness, why is a standard lime solution necessary ? What should be the characteristics of the lather produced by the soap solution ? Why is alcohol used as a solvent for the soap ? What is the underlying principle of this test? How may lead, copper, or iron be detected in water? How may you distinguish between the respective sulphides of the above metals? How may the above test respecting any one of the metals be corrobo- rated ? How delicate is the test, as regards lead ? How might a quan- titative determination of these metals be made? What is the principal reagent used in the test for phosphates ? How may a bacteriological examination of water be made ? Where is it best to make the inoculations, and why ? What precautions must always be observed in such examinations? What are some of the characteristics of good milk? What may affect its color ? Its reaction ? Its specific gravity ? How is it usually sophisticated or adulterated ? How is the percentage of total solids de- termined ? Of fats? What would a high percentage of ash indicate? Give a test for.annatto. For boric acid. W T hat are the characteristics of good butter? What is the differ- ence between it and oleo-margarine and similar compounds? What two kinds of fatty acids does butter-fat contain ? What are some of the distinctions between butter-fat and beef-fat or mutton-fat? How is the specific gravity of buttei--fat determined? The melting-point? The percentage of insoluble fatty acids ? What are some of the properties of good wheat-flour ? Of wheaten bread? How is the percentage of gluten in flour determined? The presence of added mineral substances? What does a low percentage of gluten indicate? In what kind of flour are parasites, etc., found ? What is a test for alum in bread? Should bread contain any alum? What flours or starches may be used to sophisticate wheat-flour? CHAPTER XXIII. QUAKANTINE. (By WALTER WYMAN, M.D., Surgeon-General United States Marine-Hospital Service, and H. D. GEDDINGS, M.D., Passed Assistant Surgeon Marine-Hospital Service.) BY quarantine is meant the adoption of restrictive measures to prevent the introduction of diseases from one country or locality into another. The term itself conveys no definite idea, being derived through the Italian from the Latin " quadraginta," meaning " forty " and implying forty days, the period of deten- tion imposed on vessels by the first quarantines established at Venice in 1403. The old significance of the term is entirely' lost in its present application, which is quite general. Thus, besides regular maritime quarantine, mention is often made of land, railroad, cattle, shot-gun, house, and even room quaran- tines. The name of a disease or article of merchandise may be used in prefix, as in " yellow-fever quarantine," small-pox, cholera, or rag quarantine. Moreover, quarantines are described as properly beginning at the port of departure, and as quaran- tines of inspection only, the fumigation and detention being imposed at some neighboring station. The term, therefore, is applied not only to establishments, but indifferently to persons, animals, diseases, localities, and measures. There is need of a clear understanding with regard to the term, for when, as occasionally, quarantine is ridiculed, or the assertion is made that the English disbelieve in quarantine, a wrong impression will be received, unless it is understood that only particular and obsolete forms of quarantine are meant, and not quarantine in the broad sense just mentioned. The subject admits of two natural divisions maritime and land quarantine ; but before describing them attention is called to the following table, containing a list of diseases that are ordi- narily found in official quarantine proclamations : (441) 442 TEXT-BOOK OF HYGIENE. TABLE XXXII. QUABANTINABLE DISEASES. DISEASE. PERIOD OF INCUBATION, IN DAYS. Shortest. Longest. Usual. Authority and Remarks. 3 1 2 1 5 7 2 7 1 5 1 8 11 14 21 20 14 10 28 weeks. 7 10 3 to 5 i 2 to 4 5 to 14 10 10 2 to 5 21 4 to 7 6 5 Kitisato. Da Costa, Bavtholow, Geddings. Bartholow. Bristow. Da Costa. Da Costa. Bartholow. Bartholow. Da Costa. Bartholow. Bartholow. Undetermined. Yellow fever . . . Cholera Typhus fever . . . Small-pox .... Diphtheria. . . . Typhoid fever . . Scarlet fever . . . Relapsing fever . . Den r ue Leprosy The above list illustrates the growth of the sanitary idea and belief in quarantine. For many years, as now at some ports, the list was limited to yellow fever, typhus, cholera, and small-pox. It was thus limited at Boston prior to 1881, since which date diphtheria, scarlet fever, typhoid fever, and measles have been added. The statutes of New York define as quaran- tinable " yellow fever, measles, cholera, typhus or ship fever, small-pox, scarlatina, diphtheria, relapsing fever, and any dis- ease of a contagious, infectious, or pestilential character, which shall be considered by the health officer dangerous to the public health." At Gibraltar, the English sanitary authorities include dengue and epidemic rose-rash among the diseases subject to their quarantine regulations. t The most recent addition to the list in this country is leprosy, to prevent the introduction of which, and in accord- ance with a resolution of the American Public Health Associa- tion, a prohibitory circular was issued by the Surgeon-General of the Marine-Hospital Service, December 23, 1889. FOREIGN QUARANTINE. 443 Other diseases which may properly call for quarantine are mumps, whooping-cough, chicken-pox, epidemic dysentery, glanders, tetanus, beriberi, epidemic influenza, and pulmonary tuberculosis. Influenza may be considered quarantinable under certain circumstances, a successful quarantine being reported by Dr. Trudeau, whose cottage sanitarium, in the Adirondacks, New York, was thus kept exempt during the epidemic of 1890. With regard to pulmonary tuberculosis the ground is taken by the writer that this disease, at least among immigrants, should be excluded from the United States by quarantine. FOREIGN QUARANTINE. The object of maritime quarantine being protection against the importation of contagious or infectious disease, chiefly from abroad, through the medium of vessels, their crews, passengers, and cargoes, it is most logical that restrictive measures should begin at the port of departure. Following are the regulations prepared by the Supervising Surgeon-General United States Marine-Hospital Service, and promulgated by the Secretary of the Treasury, April 26, 1894. All quarantine regulations are subject to occasional revision under the Act of Congress ap- proved February 15, 1893. U. S. QUARANTINE REGULATIONS TO BE OBSERVED AT FOREIGN PORTS AND AT SEA. ARTICLE I. BILLS OF HEALTH. Par. 1. Masters of vessels departing from any foreign port for a port in the United States must obtain a bill of health in duplicate, signed by the proper officer or officers of the United States, as provided for by law. The following frm is prescribed : Par 2. Bill of health : Form No. 1931 a. UNITED STATES BILL OF HEALTH. Name of vessel, . Nationality, . Rig, . Master, . Ton- nage, gross, ; net, . Iron or wood. Number of compartments for cargo, ; for steerage passengers, ; for crew, . Name of medical officer, . 444 TEXT-BOOK OF HYGIENE. Number of officers, . Number of crew, including petty officers, . Number of passengers, cabin, . Number of passengers, steerage, . Number of persons on board, all told, . Port of departure, . Where last from, . Number of cases of sickness, and character, during last voyage, Vessel engaged in trade, and plies between and Sanitary condition of vessel, . Nature, sanitary history, and condition of cargo, . Source and wholesomcness of water-supply, . Source and wholesomeness of food-supply, . Sanitary history and health of officers and crew, . Sanitary history and health of passengers, cabin, . Sanitary history and health of passengers, steerage, . Sanitary history and condition of their effects, . Prevailing diseases at port and vicinity, . Number of cases and deaths from the following-named diseases during the past two weeks : Diseases. No. of Cases. No. of Deaths. Yellow fever Asiatic cholera Cholera nostras, or cholerine Small-pox Typhus Any conditions affecting the public health existing in the port of departure, or vicinity, to be here stated, . I certify that .the vessel has complied with the rules and regulations made under the act of February 15, 1893, and that the vessel leaves this port bound for , United States of America, via . Given under my hand and seal this day of , 189 . (Signature of consular officer :) , Par. 3. Vessels clearing from a foreign port for any port in the United States, and entering or calling at intermediate ports, must pro- cure at all said ports a supplemental bill of health signed as provided in Article 1. If a quarantinable disease has appeared on board the vessel after leaving the original port of departure, or other circumstances presumably render the vessel infected, the supplemental bill of health should be with- held until stich sanitary measures have been taken as are necessary. The following form is prescribed : , Par. 4 : SUPPLEMENTAL BILL OP HEALTH. Port of . Vessel , bound from to , U. S. A. Sanitary condition of port : . State diseases prevailing at port and in surrounding country . Number of cases and the deaths from the following-named diseases during the past two weeks : FOREIGN QUARANTINE. 445 Diseases. No. Cases. No. Deaths. Remarks. (Any condition affecting the public health existing port, to be stated here. ) in the Yellow fever Asiatic cholera Small-pox Typhus.... Number and Sanitary Condition of Passengers Taken on at this Port, and Sanitary Condition of Effects. Cabin, No. . Sanitary condition and history . Steerage, No. Sanitary condition and history (Cancel Form A, B, or C, as the case requires.) Form. A. To the best of my knowledge and belief (Form A will be used at intermediate ports where the vessel does not enter or clear.) B. I have satisfied myself that (Form B will be used at intermediate ports where the vessel enters and clears.) no quarantinable disease has appeared aboard since leaving . C. Since leaving - the following quarantinable disease has appeared on board and I certify that the necessary sanitary measures have been taken. I certify also that with reference to the passengers, effects, and cargo, taken on at this port, the vessel has complied with the rules and regulations made under the act of February 15, 1893. Given under my hand and seal this day of , 189 . (Signature of consular officer :) ARTICLE II. INSPECTION. Par. 1. The officer issuing the bill of health will satisfy himself, by inspection if necessary, that the conditions certified to therein are true. Par. 2. Inspection is required of (a) All vessels from ports at which cholera prevails, or at which yellow fever, small-pox, or typhus fever prevails in epidemic form. (6) All vessels carrying steerage passengers. But the inspection of this class may be limited to said passengers and their living-apartments, if from a healthy port. Par. 3. Inspection of the vessel is such an examination of the vessel, cargo, passengers, crew, personal effects of same, and including exam- ination of manifests and other papers, food- and water- supply, as will enable him to determine if these regulations have been complied with. Par. 4. When an inspection is required, it should be made by day- light, as late as practicable before sailing. The vessel should be in- spected before the passengers go aboard ; the passengers just before embarkation, and the crew on deck ; and no cargo or person should be allowed to come aboard after such inspection except by permission of the officer issuing the bill of health. 446 TEXT-BOOK OF HYGIENE. ARTICLE III. REQUIREMENTS WITH REGARD TO VESSELS. Par. 1. Vessels, prior to stowing cargo or receiving passengers, shall be mechanically clean in all parts, especially the hold, forecastle, and steerage ; the bilges and limbers free from odor and deposit. The air- streaks should be sufficient in number and open for ventilation. Disin- fection of the vessel may be required by the medical officer of the United States. Par. 2. If any infectious disease has occurred during the last voyage, the portions of the vessel liable to have been infected should be disin- fected. When required, this should be done by one of the methods hereinafter described. Par. 3. The air-space and ventilation must conform to the provisions of the act of Congress approved August 2, 1882, entitled, " An act to regulate the carriage of passengers by sea." 1 Par. 4. The food- and water- supply should be sufficient, and water for drinking purposes, free from possibility of pollution, should be easily accessible. Par. 5. Vessels departing from a port where cholera prevails should have two medical officers, if more than 250 steerage passengers are carried. Par. 6. All bedding provided for steerage passengers must be de- stroyed or disinfected before being again used or landed, and mattresses and pillows used by steerage passengers shall not be landed. Par. 7. The hospitals of vessels carrying steerage passengers should be located on the upper or second deck, and not in direct communication with any steerage compartment. Par. 8. Excepting when absolutely required, no solid partitions should be placed in any steerage compartment, obstructing light and air. ARTICLE IV. CARGO. Par. 1. At ports infected with cholera, earth, sand, loam, soft or porous rock should not be taken as ballast. Nor, at ports infected with yellow fever, should such ballast be allowed on board vessels clearing for ports south of the southern boundary of Maryland, when better material, such as hard rock, is obtainable, or when it is possible to use water ballast. Par. 2. Certain food-products, namely, unsalted meats, sausages, dressed poultry, dried and smoked meats, rennets, fresh butter, fresh milk (unsterilized), fresh cheese, fresh bread, fresh vegetables, coming 1 Computation of air-spaee in any steerage compartment must not include the space taken up by bunks, mattresses, life-preservers, or personal effects. FOREIGN QUARANTINE. 447 from cholera-infected localities, or through such localities, if exposed to infection therein, should not be shipped. Par. 3. Fresh fruits from districts where cholera prevails shall be shipped only under such sanitary supervision as will enable the inspector to certify that they have not been exposed to infection. Par. 4. Articles of merchandise, personal effects, and bedding, coining from a district known to be infected, or as to the origin of which no positive evidence can be obtained, and which the consular or medical officer has reason to believe are infected, should be subjected to disinfec- tion prior to shipment by processes prescribed for articles according to their class. Par. 5. New merchandise in general may be accepted for shipment without question ; and articles of new merchandise, textile fabrics, and the like, which have been packed or prepared for shipment in an infected port or place, with a special view to protect the same from moisture inci- dent to the voyage, may be accepted and exempted from disinfection. Par. 6. All rags and all textile fabrics used in the manufacture of paper, collected or packed in any foreign port or place, must, prior to shipment to the United States,- be subjected to disinfection by one of the prescribed methods : (Old jute bags, old cotton bags, old rope, new cotton and linen cuttings from factories not included.) Par. 7. Rags, old jute, old gunny, old rope, and similar articles, gathered or packed or handled in any port or place where cholera or yellow fever prevails, or small-pox or typhus fever prevails in epidemic form, should not be shipped until the officer issuing the bill of health shall be satisfied that the port or place has been for thirty days free from such infection, and after the disinfection of the articles. Par. 8. New feathers for bedding ; human and other hair, unmanu- factured ; bristles; wool; hides not chemically cured, coining from a district where cholera prevails, shatt be refused shipment until thirty days have elapsed since last exposure, unless unpacked and disinfected as hereinafter provided. Feathers which have been used should be disinfected, and invariably by steam. Par. 9. The articles enumerated in the preceding paragraph coming from a district where yellow fever prevails, destined for ports or places south of the southern boundary of Maryland during the quarantine season, or where small-pox or typhus fever prevails in epidemic form, should be refused shipment, unless disinfected as hereinafter provided. Par. 10. Articles sucli as gelatin, glue, glue-stock, fish-glue, fish- bladders, fish-skins, sausage-casings, bladders, dried blood, having been 448 TEXT-BOOK OF HYGIENE. in any way liable to infection in the process of preparation, gathering, or shipment, should be disinfected. Par. 11. Any covering shipped from or through an infected port or place, and which the consul or medical officer has reason to believe infected, should be disinfected. Par. 12. Any article presumably infected, which cannot be disin- fected, should not be shipped. 1 ARTICLE V. PASSENGERS AND CREW. Par. 1. Passengers, for the purposes of these regulations, are di- vided into two classes, cabin and steerage. Par. 2. No person suffering from a quarantinable disease, or scarlet fever, measles, or diphtheria, should be allowed to ship. Par. 3. Steerage passengers and crew, coming from districts where small-pox prevails in epidemic form, or who have been exposed to small- pox, shall be vaccinated before embarkation, unless they show evidence of immunity to small-pox by previous attack or recent successful vaccina- tion. Par. 4. Steerage passengers and crew who, in the opinion of the inspecting officers, have been exposed to the infection of typhus fever, should not be allowed to embark for a period of at least fourteen days after such exposure and the disinfection of their baggage. Par. 5. When practicable, passengers should not ship from an infected port. Steerage passengers coming from cholera-infected dis- tricts must be detained five days in suitable houses or barracks located where there is no danger from infection, and all baggage disinfected as hereinafter provided ; the said period of five days to begin only after the bathing of the passengers, disinfection of all their baggage and apparel, removal of all food brought with them, and isolation from others not so treated. Par. 6. Steerage passengers from districts not infected with cholera, shipping at a port infected with cholera, unless passed through without danger of infection and no communication allowed between passengers and the infected locality, should be treated as those in the last paragraph. Par. 7. Prior to sailing from ports infected with cholera, each pas- senger of the cabin class should produce satisfactory evidence as to his exact place of abode during the five da3's immediately preceding embark- ation ; and if it appear that he or his baggage has been exposed to con- tagion, such passenger should be detained such length of time as shall be deemed necessary by the inspecting officer, and the baggage should be disinfected. 1 Upholstered furniture, sheep-skins used as wearing-apparel, bedding, bones, horns, and hoofs. FOREIGN QUARANTINE. 449 Par. 8. The rules prescribed for the disinfection of the baggage and personal effects of passengers and crew coming from cholera-infected ports should also be observed with regard to passengers and crew coming from ports and places where plague, yellow fever, typhus fever, or small- pox is prevailing in an epidemic form. Par. 9. Should cholera break out in the barracks or houses in which the passengers are undergoing the five days' observation, no pas- senger from said house or barracks should embark until five days' isolation from the last case and a repetition of the sanitary measures previously taken. Par. 10. All baggage of steerage passengers destined for the United States shall be labeled. If the bagguge has been inspected and passed, the label shall be a red label bearing the name of the port, the steam-ship on which the baggage is to be carried, the word " inspected" in large type, the date of inspection, and the seal or stamp of the consular or medical officer of the United States. All baggage that has been disin- fected shall bear a yellow label, upon which shall be printed the name of the port, the steam-ship upon which the baggage is to be carried, the word " disinfected" in large type, the date of disinfection, and the seal or stamp of the consular or medical officer of the United States. It is understood, and it will be so printed on the blank, that the label is not valid unless bearing the consular or medical officer's stamp or seal. Par. 11. Each steerage passenger should be furnished with an inspection card. This card, stamped by the consular or medical officer, is to be issued to every member of a family as well as to the head thereof. Par. 12. Form of inspection card (see next page). Par. 13. Cabin passengers from cholera-infected ports or places should be given a special inspection card, on which shall be printed the port of departure, name of passenger, name of ship, date of departure, and an indicated space for the seal or stamp of the consular or medical officer. Par. 14. The baggage of such cabin passengers shall be labeled in the same manner as steerage baggage. Par. 15. In a port where cholera prevails, or where yellow fever prevails in epidemic form, the crews of passenger-ships should remain on board during their stay. Should additional men be shipped, the same precautions should be observed with them as in the case of steerage passengers. If it is considered necessary, the crews of freight- ships may be similarly treated, at the discretion of the medical officer. Par. 16. Passengers and crews, merchandise and baggage, prior to shipment at u non-infected port, but coming from an infected locality, 450 TEXT-BOOK OF HYGIENE. (Immigrants and Steerage Passengers.) Port of Departure Date of Departure, Name of Ship Name of Immigrant Last Permanent Residence Inspected and passed at Passed at quarantine, port of Passed by Immigration Bu- ., U. S. reau, port of . C Seal or Stamp } < of Consular or Med- > ( ical Officer. ) (Date.) (Date.) (The following to be filled in by ship's surgeon or agent prior to or after embarkation.) J * J Berth No. i i >, * 3 9 i 2 1 S t jj t> .cj t*> ^ (M ^y sulphur dioxide, 10-per-cent. strength, twenty-four hours in the cabin and forecastle and forty-eight hours in the hold ; and (second) flushing or washing with acid solution of bichloride of mercury in large quantity (1 to 800). The bilges to be first flushed with sea-water, pumped out, and then treated with the acid solution of bichloride of mercury in large quantity, allowed to remain in long con- tact. In addition to the sulphur fumigation of such apartments, the cabins, forecastle, and other apartments, and their contents, to be treated as those on iron vessels. Cargo. Par. 3. Disinfection of rags and old jute, etc., shall be by one of the following methods : (a) By boiling in water for not less than thirty minutes. (6) By steam at the temperature of 100 C. for not less than thirty minutes after such temperature is reached. (c) By exposure for not less than six hours in a closed compartment to a 4-per-cent. strength (per volume) of sulphur-dioxide gas, made by burning roll sulphur or by the liberation of liquefied sulphur dioxide, allowance to be made for leakage by increasing the amount of sulphur. Par. 4. In all of the above methods, the rags, old jute, etc., must be unbaled, and in the disinfection by steam or sulphur the rags must be loosely spread on racks (preferably wire netting) in layers of not more than six inches in depth, and in such a manner as to insure the diffusion of the gas to all parts alike. The articles must not at any time occupy more than 50 per cent, of the total cubic space, and the exposure to date from the complete com- bustion of the sulphur. Par. 5. New feathers for bedding shall be disinfected by one of the following methods : ' Polished metal is injured by mercury, and leather by steam. 454 TEXT-BOOK OF HYGIENE. (a) By steam at a temperature of 100 C. for a period of thirty minutes after such temperature has been reached. (6) B} r exposure to sulphur dioxide, 4-per-cent. strength per volume, for not less than six hours. Par. 6. Human hair or other hair, unmanufactured, and bristles, to be disinfected by sulphur dioxide, 4-per-cent. strength per volume, six hours, or, if not clean, by a solution of pure carbolic acid, 4-per-cent. strength, the articles to be thoroughly saturated. Par. 7. Wool to be disinfected by sulphur dioxide, 4-per-cent. strength per volume, for not less tban twenty hours, the wool to be tin- baled and loosely spread on racks, as in the manner provided for the disinfection of rags. Par. 8. Hides to be disinfected by '"sulphur dioxide, 4-per-cent. strength per volume, for not less than twenty hours, or by thorough saturation with a solution of pure carbolic acid, 4-per-cent. strength ; hides to be invariably unbaled for the purpose. Par. 9. Articles mentioned in paragraph 10, Article IV, should be disinfected by being spread on racks and exposed to sulphur dioxide, 4 per cent, per volume, twenty hours. , Par. 10. Coverings should be disinfected (a) In the hold, by exposure to sulphur dioxide, 10-per-cent. strength per volume, for twelve hours ; the cargo being so stowed as to allow access to all parts of such surfaces. (6) By breaking bulk and exposure to sulphur dioxide, 4-per-cent. strength per volume, for twenty-four hours. (c) By wetting thoroughly with solution of bichloride of mercury 1 to 800. Par. 11. The disinfection of personal effects, prescribed by these regulations, should be as follows : (a) Clothing and bedding should be disinfected by (1) exposure to steam from 100 to 102 C. for thirty minutes after such temperature is reached, or by boiling for thirty minutes ; (2) immersion in bichloride solution 1 to 800, or solution of pure carbolic acid, 3 per cent., until thoroughly wetted, and allowed to dry before washing. This last process (2) to be used only for articles that will be injured by steam or boiling. 1 (6) Cooking and eating utensils should be immersed in boiling water. NOTE. A 4 per cent, per volume strength of sulphur dioxide can be obtained by burning not less than 4 pounds 2 ounces of sulphur to each 1000 cubic feet of space ; the compartment to be air-tight. 1 Articles of rubber, leather, celluloid, gutta-percha, hats, furs, skins, and similar arti- cles, are injured by steam or boiling. FOREIGN QUARANTINE. 455 A 10 per cent, per volume strength can only be obtained by one of the following methods : By the use of a special furnace, or by liquefied sulphur-dioxide gas. ARTICLE VIII. RECORDS, REPORTS, ETC. The officer making the inspection will preserve in his office a record of each inspection made. A copy of said record will be forwarded weekly to the Supervising Surgeon-General of the Marine-Hospital Service, at Washington, D. C. In addition to the duties already prescribed, the medical officer, when detailed in accordance with the Act of Congress approved Febru- ary 15, 1893, shall furnish such reports to the Supervising Surgeon- General of the Marine-Hospital Service as may be required by the latter. NOTES FOR THE INFORMATION OF MASTERS OF VESSELS AND OTHERS. FORMULAE FOB STRONG DISINFECTING SOLUTIONS. Bichloride of Mercury. (1 : 500. ) Bichloride of mercury 1 part. Hydrochloric acid 2 parts. Water 500 parts. Mix. Carbolic Acid. Carbolic acid (pure) 50 parts. Warm water 1000 parts. FORMULA FOR WEAK SOLUTIONS. Bichloride of Mercury. (1 : 1000. ) Bichloride of mercury 1 part. Hydrochloric acid 2 parts. Water 1000 parts. Carbolic Acid. Carbolic acid (pure) 25 parts. Warm water 1000 parts. DISINFECTION OF HOSPITALS, INFECTED COMPARMENTS, ETC. (a) By steam as provided in Article VII, paragraph (c); or, when steam is not available (6) By methods prescribed in Article VII, paragraphs (a) and (c). Water-closets, etc., should be disinfected by strong solution of bichloride of mercury or carbolic acid. 1 It is suggested that a vessel should carry, for every 100 passen- gers : Bichloride of mercury, 5 pounds; hydrochloric acid, 10 pounds; carbolic acid, 10 pounds. 1 The use of these disinfecting solutions does not preclude the additional use of hypo- chlorite of lime. 456 TEXT-BOOK OF HYGIENE. EFFICIENCY OF FOREIGN REGULATIONS. The wisdom of this method of procedure and the efficient working of these regulations are demonstrated by the following statement taken from the report of the medical officer of the Marine-Hospital Service on duty at Naples, Italy, where, during the summer of 1893, cholera was epidemic : " From the 15th of July to August 17th there were eight vessels cleared from Naples with steerage passengers, four for New York and four for South American ports. The first to leave was the Karamania, for New York, on July 15th. No cholera at that time existed in Naples. The first case occurred in Naples on the night of the 16th, and the result of the bac- teriological examination was not known until the afternoon of the 17th or morning of the 18th. " The passengers for the Karamania and the ship itself were put through the established routine. The ship was cleaned; ventilation, etc., altered to conform with the United States law ; closets and hospitals put in good order ; water- and food- supply attended to ; passengers inspected and vaccinated, and both their baggage and clothing searched for food. Three days after sailing, i.e., on the 18th, a death from cholera occurred, and just before reaching New York there were two more. It is not unlikely that the infection in the first cases was traceable to the same source as those occurring in Naples on the 16th. It is more than probable that but for the careful exclusion of food brought by passengers there would have been more cases on the remaining three ships for the United States. The regulations governing infected ports were rigidly enforced. The first vessel to leave, four days after the cholera was an- nounced, was the Massilia. Her passengers were met at the trains and conducted immediately on board ; were there isolated three days, and all their baggage transferred across city unopened. All food was carefully looked into ; all from persons or baggage excluded ; and the baggage of a few, about whose antecedents there was doubt, disinfected by steam. The ship was warped FOREIGN QUARANTINE. 457 out some distance from the pier every night, and an inspector kept on board night and day. There being no cholera known to exist anywhere in Italy outside of Naples, it was not thought necessary to disinfect all baggage or isolate five days. She arrived safely in New York without mishap. The remaining two for the United States were the Wcser and Caslimire ; in both cases the regulations were enforced in detail. One lay about a mile and a half off shore during her five days. The other cruised at sea. In both cases an inspector was kept aboard day and night. Both escaped cholera. " The four for South America, with the result in each case, were as follow : The figures are not official, but are practically accurate in every respect. All were turned back by the South American authorities: Vencinzio Florio, about 50 deaths; Andrea Dorio, 90 on way out, total not ascertained ; El Remo, 84 deaths ; Carlo R., -about 230 deaths. " To summarize,. then, eight ships left Naples. The water- supply was the same and the food about the same ; the class of passengers identical, and their places of origin similar, in many cases identical. All four leaving without precautions became floating pest-houses. Of the four for the United States, the one leaving before cholera appeared in Naples had 3 deaths ; the other three were made to conform to the regulations, and all escaped. In other words, every ship that left Naples had cholera except those in whose case the ' infected port ' regula- tions were carried out ; and of the five that had cholera, the only one that escaped with less than 50 deaths was the one on which our ' non-infected port ' regulations were enforced, she having only 3 deaths en route. In addition, the enforcement of the regulations compelled the abandonment of a number of other sailings for the United States. The escape of the Massilia, Caslimire, and Weser may be ' post,' not ' propter hoc,' but we certainly have the right to consider the evidence to be strongly on the side of ' propter.' ' 458 TEXT-BOOK OF HYGIENE. DOMESTIC QUARANTINE. The trans-oceanic part of the voyage completed, the vessel arrives in the waters of the United States, and here she is con- fronted by a municipal, State, or national quarantine station, where the question will be determined whether the measures prescribed have been carried out, whether they have been effect- ive in the particular case, and, in fine, whether the vessel, her crew, passengers, and cargo are or are not a menace to the health of the city and the country at large. MARITIME QUARANTINE STATIONS. In describing a maritime quarantine station it should be borne in mind that the details in the plant must vary in accord- ance with the special demands of each port. Thus, it is not to be expected that at Charleston, where immigration is limited, there should be the same provisions for detention of immigrants as at New York, through whose por- tals more than one-third of a million of immigrants pass each year ; or San Francisco, where enter the throng of travelers and immigrants from the far East. We should not expect that Boston, in the more salubrious North, would have the means or adopt the practice of discharging ballast, cleaning and fumigating every vessel from an infected port, which is the invariable custom at Pensacola. But, leaving these variations for subsequent notice, the first thing to be considered, in the establishment of a complete mari- time quarantine, is proper location. This must be at a point remote from city or village boundaries, and not likely to be encroached upon by urban growth. It should be more or less removed from the channels of commerce, and yet be easily accessible. Indifference to proper location could very readily make *the quarantine station a source of danger instead of a protection. DOMESTIC QUARANTINE. 459 THE QUARANTINE PLANT. The requirements of a maritime quarantine station may be enumerated as follows : 1 . A boarding-station. 2. A boarding- vessel. 3. Anchorages. 4. Wharves with warehouse, disin- fecting machinery, and machinery for discharge of ballast. 5. Lazaretto, or hospital for treatment of contagious diseases. 6. Hospital for treatment of non-contagious diseases. 7. Barracks for the detention, in groups, of suspects, or persons who have been exposed to contagion or infection. 8. Bath-house. 9. Water-supply. 10. A cremation furnace. 11. Quarters for medical officers. 12. Laundry. 1. THE BOARDING-STATION. This includes a boat-house, with boatmen's quarters so located as to avoid infection from the Lazaretto, and to be within easy reach of passing com- merce. 2. BOARDING- VESSEL. The facilities for boarding and in- spection will vary with the location of the station, whether within the limits of a land-locked harbor or exposed to the full force of wind and sea. In the former case a steam- or naphtha- launch, or even a row-boat, will suffice ; but in the latter case the boarding-boat must be a steamer, preferably of the sea-going tug-boat type, for it must be remembered that any delay in making the inspection inflicts hardship on commerce, and must inevitably produce discontent and complaint. 3. ANCHORAGES. Two anchorages, one for infected and one for non-infected vessels. The anchorage for the detention of the infected vessel should be conveniently removed from the main establishment and safely remote from the track of com- merce. Its position should be sheltered, and good holding- ground for vessels' anchors is of the first importance. The channel to the anchorages, and, if necessary, their boundaries, should be plainly marked by buoys. 4. WHARVES. A wharf or pier is a prime essential in the equipment of a complete station, and should be located in water at least twenty feet deep, and should be of such length 460 TEXT-BOOK OF HYGIENE. that the largest vessels trading at the port can lie there safely; at least, in all ordinary weather. Upon this wharf there should be a warehouse for the storage of baggage and portions of cargo (practically, cargo is never fully discharged, being disin- fected in situ}. On the wharf should be placed the steam disinfecting chambers, sulphur-furnaces, and tanks for holding disinfecting solutions. (At certain stations the disinfecting apparatus is necessarily placed on a barge.) When required, a special, additional wharf should be provided for the discharge of ballast. Steam Disinfecting Chambers. The principle of disinfec- tion by steam was first advocated by Dr. A. N. Bell, of Brook- lyn ; but the credit of first designing apparatus for the special purpose belongs to Dr. Joseph Holt, and his design was subse- quently improved upon by Dr. Wilkinson and others. Steam Chambers. These chambers consisted of cylindrical shells, made of strong boiler-iron, 40 to 50 feet long and 7 to 8 feet in diameter (inside measurement), furnished with doors at each end. The steam was admitted directly to the interior of the chamber, and in addition there was a coil of pipe for the application of dry heat. These chambers were fairly efficient in action, but there was a great waste of space, and with the exercise of every possible care there was always more or less wetting of fabrics by the water of condensation. Many im- provements have been made from time to time in the construc- tion of steam disinfecting chambers, those constructed for the national quarantine station at San Francisco, Cal., being of the same general construction, but dispensing with the coil of pipe, and substituting therefor a jacket surrounding the entire chamber. The most recent steam chambers are the joint plan of Passed Assistant Surgeon J. J. Kinyoun, Marine-Hospital Service, and Mr. W. H. Francis, of the Kensington Engine- W r orks of Phil- adelphia. They are of rectangular section, 16 feet in length, 4 feet 6 inches in width, and 5 feet 6 inches in height, and are DOMESTIC QUARANTINE. 461 provided with steam-tight doors opening at either end. The chambers are constructed of an inner and outer steel shell 2| inches apart, with cast-iron end frames, intermediate truss bands, and of stay-bolt construction. The doors have concave steel plates riveted to cast angle frames fitted with heavy rubber gaskets ; they are handled by convenient cranes, and drawn tight by drop-forged steel eye- bolts, swinging in and out of slots in the door-frames. The rectangular form is adopted in preference to the round, as it gives the most effective space during exposure, with little loss of steam, and enables cars on tracks to be readily handled in and out. The jacket is used to give perfect circulation and distribution of heat, to prevent condensation, and to dry the goods exposed. The jackets, which are filled with steam during the entire operation of the plant, make the chambers drying ovens ; so that the articles to be disinfected are brought to the required temperature before the admission of steam to the inner chamber, and are thoroughly dried after the steam has been exhausted. In the experiments of Professor Koch in connection with Dr. Wollfhiigel it was found that hot air alone, even at a tem- perature of 230 to 248 F., after an exposure of three hours, would not with certainty destroy bacilli and spores. It is neces- sary, therefore, to eliminate the possibility of the pocketing of air, or of a mixture of air and steam, during exposure. To prevent this a vacuum pump is attached to the system of piping, whereby a vacuum of 15 to 20 inches is produced in the chamber prior to the admission of steam. In previous chambers this important point was neglected, and this accounts for the unreliable results obtained by a number of disinfecting plants. For convenience of handling the goods to be disinfected, each chamber is provided with two cars of light wrought- iron construction, with removable trays with bottoms of galvan- ized-iron wire netting, and having a series of bronze wardrobe- hooks in the top of the frame-work, thus permitting the articles 462 TEXT-BOOK OF HYGIENE. to be laid out upon the trays, or, in the case of finer clothing, to be hung upon the hooks. The doors at both ends allow the cars to be brought in at one end and removed at the other, thus securing complete separation of infected and disinfected articles. After exposure the cars, upon being unloaded, are returned to the working end of the chamber by means of transfer tables and side-tracks, permitting a continuous working of the plant. The system of piping is so arranged that steam may be admitted to the top or bottom of the chamber at will, through several openings, and has perfect circulation. Galvanized-iron hoods are placed in the chambers, so that steam is not forced directly on the clothing. The chamber is provided with ther- mometers to register the temperature, vacuum and steam gauges, safety-valves, traps, and is covered with magnesia non-conducting covering. /S 'ul phur- Furnace. For a long time the method of sulphur fumigation pursued was to put into iron pots a quantity of sul- phur varying from three to four pounds to one thousand cubic feet, igniting this by means of alcohol, and to place them in the hold or apartment to be disinfected. An apparatus was de- signed by Passed Assistant Surgeon J. J. Kinyoun, Marine-Hos- pital Service, for the purpose of producing SO 2 in greater per- centage, and consisted of a furnace built on the reverberatory plan, with a series of shelves arranged one above another, each shelf carrying a pan of burning sulphur. A forced draught is kept up by means of a fan-blower connected at the bottom. The draught of air charged from the burning sulphur is made to reach and pass over the shelf above by means of apertures made by shortening the shelves alternately at their rear and front extremities. With an experimental furnace, Dr. Kinyoun states that "repeated experiments gave from 14 to 16 per cent, of SO 2 , temperature 21 C, while burning sulphur in a closed place gave only 6 per cent, at 21 C., i.e., the air would not support the combustion of sulphur above that percentage." This has been almost entirely superseded by a furnace that DOMESTIC QUARANTINE. 463 is simpler in construction, and which has given admirable re- sults in practice. The furnace is douhle, and has been provided with small fire-boxes at each end, over which are placed two shallow cast-iron pans five feet long, and the whole inclosed in a frame of sheet-iron. The sulphur is placed in the pans and a fire lighted in the furnaces, melting the sulphur, which quickly ignites. To prevent too rapid combustion baffle plates are arranged, and the proper quantity of air is admitted through adjustable valves in the furnace-fronts. The fumes of sulphur dioxide thus generated are collected and carried into a reser- voir, from which they are suckeol by an exhaust fan, and are thence forced through piping and large flexible hose to the apartment to be fumigated. The sulphur-furnace in use at the Louisiana Quarantine Station is the same in general principle, with the addition that the air supplied to the burning sulphur is aspirated from the hold of the vessel, and then forced into the furnace. Disinfection by Germicidal Solutions.- The apparatus for the use of the disinfecting solutions consist of a tank or tanks elevated above the level of the floor of the wharf to a sufficient height to force the solution through a hose and nozzle to the parts of the ship to be reached. The tank is to be filled by a steam-pump, and the solution is easily made by surmounting the tank with a keg perforated by numerous holes, in which keg the powdered bichloride is to be put, and the water for filling the tank pumped over it. It is a much better plan to have the bichloride solution distributed by means of a special pump (made of iron to pre- vent amalgamation), as, with the pressure of the pump behind it, it penetrates much more deeply into cracks and crevices and, hyfact, knocks the dirt and filth out of them. 5 and 6. HOSPITALS. The propriety of having separate hospitals for contagious and non-contagious diseases is so obvious that it need not be dwelt on here, and the necessity of a separate establishment for suspects, until the nature of 464 TEXT-BOOK OF HYGIENE. their complaint can be positively made out, is patent and only in accord with expediency and the 'ordinary instincts of humanity. 7. BARRACKS. Barracks for the detention of suspects are not an essential part of the equipment of every quarantine station, but are a necessity only at such stations as are situated at the great ports of entry, which are the ports of arrival of the vast hordes of immigrants who seek our shores. Barracks are an indispensable adjunct in the management of ship-loads of immigrants suspected of being infected with cholera, typhus fever, and small-pox, and w.ould be required in the case of yellow fever but for the fact that there is little or no immigration from the yellow-fever zone. The barracks should be commodious, substantial, and yet of simple and inexpensive construction. They should be well ventilated and so arranged that every part of the building is under constant surveillance, and so subdivided that the inmates are divided into small groups and intercourse between the groups prevented. The immigration law requires that the im- migrants shall be listed and arranged in groups of thirty, and it would be well that this number be preserved as the unit for segregation. The barracks should be furnished with bunks, arranged in tiers one above the other, and furnished with bed- ding of a simple and inexpensive character. Clothing of a simple but sufficient kind, and capable of easy laundering, should be provided in sufficient quantity to furnish eacli inmate of the barracks with a change while his or her own personal effects are undergoing the process of disinfec- tion. Attached to the barracks there should be a kitchen, thoroughly equipped with all the facilities for furnishing hot food of a simple character for the number of inmates provided for by the barracks. Dining-rooms should be arranged, and special care should be taken to prevent the carrying of any food into the barracks. It is perhaps needless to say that, in the barracks, the sexes should be separated, and the better arrange- DOMESTIC QUARANTINE. 465 ment is to have two buildings, one for men and one for women and children. Latrines. Latrines of ample size should be provided, and should be so arranged that all dejecta may be received into metallic vessels containing a germicidal solution of acknowl- edged potency ; or, if the dejecta are to be- received into a sewer, there should be some provision made for their complete disin- fection prior to their discharge into the sea or a "cess-pool. 8. BATH-HOUSE. Bathing facilities are an important part of the equipment of a quarantine station designed for the hand- ling of large numbers of suspects. The best form of bath for the purpose is the shower- or rain- bath, it being more easily managed, more expeditious, and probably more efficacious than the tub-bath. The bath-house should be provided with a room for disrobing, from which the suspects will pass into the bathing- stalls proper, and there receive a bath the temperature of which is under the sole control of the bath-attendant. From the bath the suspect will pass into a robing-room, where he will be given a suit of sterile clothing, while the clothing which was re- moved in the disrobing-room is carried by proper attendants to the disinfecting apparatus, there to be rendered safe by steriliza- tion. 9. WATER-SUPPLY. An abundant supply of pure water is riot only a desideratum, but a prime necessity, at all quarantine stations where it is designed to accommodate cholera suspects. It would be desirable to provide a supply of twenty gallons per capita per day, and no arrangement will probably give such good results as the sinking of an artesian well, if the nature of the soil and the geological formation permit. If it is imprac- ticable to sink such a well, the next best plan would be to arrange for the distillation or sterilization, by boiling, of a suffi- cient quantity of water for drinking purposes. 10. CREMATORY. A crematory is a desirable part of the equipment of every quarantine station, as it admits of no argu- ment that cremation is the best possible method of disposing of 466 TEXT-BOOK OP HYGIENE. the bodies of those dead of contagious or infectious disease. In addition, it would be desirable that all garbage and waste about a quarantine station be incinerated to prevent the possibility of infection. 11 and 12. Detailed description of quarters for medical officers and of laundry is unnecessary. Having thus considered the necessities and the desiderata in the equipment of a quarantine station, it is now proper to con- sider the regulations governing them, and for this purpose are here appended the regulations prepared by the Supervising Surgeon-General of the Marine-Hospital Service, and pro- mulgated by the Secretary of the. Treasury on April 26, 1894. These regulations are to be considered a minimum for the stations under municipal arid State control, some of which have additional requirements : QUARANTINE REGULATIONS TO BE OBSERVED AT PORTS AND ON THE FRONTIERS OF THE UNITED STATES. i PREAMBLE. 1. At or convenient to the principal ports of the United States, quarantine stations should le equipped with all appliances for the inspec- tion and treatment of vessels, their passengers, crews, and cargoes. 2. At all other ports where such provisions have not been made, inspection stations should be maintained. 3. An inspection service should be maintained at every port throughout the year. 4. At a fully-equipped quarantine station there should be adequate provision for boarding and inspection, apparatus for mechanical cleaning of vessels, apparatus for steam disinfection, apparatus for disinfection with sulphur dioxide, apparatus for disinfecting solutions, hospitals for contagious and doubtful cases, detention barracks for suspects, bathing facilities, crematory, and sufficient supply of good water. 5. The personnel of quarantine stations in the 3'ellow-fever zone and on fruiters bound for Southern poi'ts should be immune against yellow fever. 6. At quarantine stations all articles liable to convey infection should be handled only by the emplo^yes of said station, unless the ser- vices of the crew are indispensable. DOMESTIC QUARANTINE. 467 7. Vessels having been treated at national quarantine stations that are located a considerable distance from the ports of entry of said vessels may be inspected by the local quarantine officer, and, if for any sanitary reason it is considered inadvisable to admit the vessel, he should report the facts immediately by telegraph, when possible, to the Supervising Surgeon-General Marine-Hospital Service, detaining the vessel pending his action. 8. The following regulations are the required minimum standard, and do not prevent the addition of such other rules as, for special reasons, may be legally made by State or local authorities. ARTICLE I. INSPECTION. 1. Vessels arriving at ports of the United States under the follow- ing conditions shall be inspected by a quarantine officer prior to entry : A. Any vessel with sickness on board. B. All vessels from foreign ports. C. Vessels from domestic ports where cholera or yellow fever prevails or where small-pox or typhus fever prevails in epidemic form. Exceptions. Vessels not carrying passengers on inland waters of the United States. Vessels from the Pacific and Atlantic coast of Brit- ish America, provided they do not carry persons or effects of persons non-resident in America for the sixty days next preceding arrival, and provided always that the port of departure be free from quarantinable disease. Vessels from other foreign ports via these excepted ports shall be inspected. D. Vessels from foreign ports carrying passengers having entered a port of the United States without complete discharge of passengers and cargo. Such vessels shall be subject to a second inspection before enter- ing any other port. Vessels from ports suspected of infection with yellow fever, having entered a port north of the southern boundary of Maryland without disinfection, shall be subjected to a second inspection before entering any port south of said latitude during the quarantine season of such port. 2. The inspections of vessels required by these regulations shall be made by daylight, except in case of vessels in distress. 3. In making the inspection of a vessel, the bill of health and clin- ical record of all cases treated during the voyage, crew and passengers' lists and manifests, and, when necessary, the ship's log shall be examined. The crew and passengers shall be mustered and examined and compared with the lists and manifests, and any discrepancies investigated. 4. No person except the quarantine officer, his employe's, United States customs officers, or agents of the vessel, shall be permitted to 468 TEXT-BOOK OF HYGIENE. board any vessel subject to quarantine inspection, until after the vessel has been inspected by the quarantine officer and given its discharge. ARTICLE II. QUARANTINE. 1. For the purpose of these regulations, the quarantinable diseases are cholera (cholerine), yellow fever, small-pox, typhus fever, and leprosy^ 2. Vessels arriving under the following conditions shall be placed in quarantine : A. With quarantiuable disease on board. B. Having had such on board during the voyage or within thirty days next preceding arrival ; or, if arriving in the quarantine season, having had yellow fever on board after March 1 of the current year, unless satisfactorily disinfected thereafter. C. From ports infected with cholera, or where typhus fever pre- vails in epidemic form, coming directly or via another foreign port, or via United States ports, unless they have complied with the United States quarantine regulations for foreign ports ; also vessels from non-infected ports, but bringing persons or cargo from places infected with cholera, yellow fever, or where typhus fever prevails in epidemic form, except as subsequently noted. D. From ports where yellow fever prevails, unless disinfected in accordance with these regulations, and not less than five days have elapsed since such disinfection. Exceptions. The following exceptions may be made to Rules C and D with regard to vessels from ports quarantined against on account of yellow fever : (a) Vessels arriving during certain seasons of the year to wit, from November 1 to May 1 may be admitted to entry. (6) Vessels bound for ports in the United States north of the southern boundary of Maryland, with good sanitary condition and his- tory, having had no sickness on board at ports of departure en route or on arrival, provided they have been five days from last infected or sus- pected port, may be allowed entry at port of destination. But if said vessels carry passengers destined for places sonth of this latitude the baggage of said passengers shall be disinfected. In making an inspection of a vessel, if from a port where yellow fever prevails, and between May 1 and November 1 of an} 7 year, the inspector shall ascertain the destination of each passenger thereon, and if bound for places south of the southern boundary of Maryland the baggage of such passenger shall be disinfected according to the rules for such articles infected with yellow fever. Such baggage shall be labeled. DOMESTIC QUARANTINE. . 469 (c) Vessels engaged in the fruit trade from ports declared safe for this purpose by the Supervising Surgeon-General Marine-Hospital Ser- vice may be admitted to entry without detention, provided that they carry no passengers and have carried no passengers from one port to another and have no household effects or personal baggage in cargo, and have complied with the special rules and regulations made by the Sec- retary of the Treasury with regard to vessels engaged in said trade. 3. All persons arriving on vessels having had small-pox on board must be vaccinated or show satisfactory evidence of recent vaccination or of having had small-pox, or be detained in quarantine for not less than fourteen days, and all effects and compartments liable to convey infection disinfected. 4. All passengers occupying apartments other than first or second cabin shall be vaccinated prior to entry, unless they can show that they have had small-pox, or have been recently successfully vaccinated, or be detained in quarantine fourteen days. 5. Vessels arriving at quarantine with leprosy on board shall not be granted pratique until the leper with his or her baggage has been removed from the vessel to the quarantine station. No case of leprosy will be landed. If the leper is an alien passenger and the vessel is from a foreign port, action will be taken as provided by the immigration laws and regu- lations of the United States. If the leper is an alien and a member of the crew and the vessel is from a foreign port, said leper shall be detained at the quarantine at the vessel's expense, until taken aboard by the same vessel when outward bound. ARTICLE III. GENERAL REQUIREMENTS AT QUARANTINES. 1. Pilots bringing infected vessels will be detained in quarantine a sufficient time to cover the period of incubation of the disease for which the vessel is quarantined, if, in the opinion of the quarantine officer, such pilots have been exposed to infection. The dunnage of pilots shall be disinfected when necessary. 2. No direct communication shall be allowed between quarantine, or any vessel in quarantine, and any person or place outside, and no com- munication except under the supervision of the quarantine officer. 3. No ballast shall be allowed to leave the quarantine station, unless disinfected. 4. Where it is impossible to disinfect cargo in situ, it shall be re- moved and disinfected in the manner provided for articles of their class in these regulations ; such articles to be unpacked and so arranged as to 470 TEXT-BOOK OF HYGIENE. allow the disinfectant used to reach every part of all surfaces of said articles. 5. Vessels arriving at any port of the United States with cholera or yellow fever aboard during the quarantine season shall be remanded to an anchorage set apart for infected vessels, there to remain until after the discharge of the passengers and purification of the vessels. 6. All passenger baggage disinfected under the requirements of these regulations shall be labeled. ARTICLE IV. TREATMENT IN QUARANTINE OF CHOLERA-INFECTED VESSELS. 1. l Remove all passengers from the vessel and all of the crew (if cholera has occurred on board) save those necessary to care for her. Place the sick in hospital and carefully isolate those specially suspected. Segregate the remainder in small groups. No communication shall be held between these groups. Those believed to be especially capable of conveying infection must not enter the barracks until they are bathed and furnished with sterile clothing ; nor shall any material capable of conveying infection be taken into the barracks, especially food. 2. If cholera has occurred in the steerage, all occupants thereof must be bathed and their clothing disinfected. 3. At once proceed with the disinfection of the hand-baggage. 4. All baggage and effects accompanying steerage passengers, and any other baggage or effects that may have been exposed to infection, must be disinfected. 5. Such articles of cargo as are liable to convey infection must be disinfected. 6. All living-apartments and furniture and such other portions of a vessel as are liable to convey infection shall be disinfected. *I. On cholera-infected vessels the water-supply must be changed without delay, the casks or tanks disinfected b}- steam or 1 0-per-cent.- solution of potassium permanganate, and after thorough rinsing refilled from a source of undoubted purity, or the water supplied must have been recently boiled. 8. Nothing shall be thrown overboard from a cholera-infected vessel, not even deck sweepings. Such things shall be burned in the furnace or in a place specially designated, but not in the galley. ARTICLE V. DISINFECTION, ETC. 1. Holds. The disinfection of iron vessels shall be as follows : (a) With cargo : If cargo is so stowed as to admit of disinfection, it and the hold may be disinfected without breaking bulk, except to such 1 It is required only if cholera has occurred on board. DOMESTIC QUARANTINE. 471 a degree as to make disinfection practicable, by sulphur dioxide, 10 per cent, per volume strength, for not less than twenty-four hours' exposure. (6) Without cargo: After mechanical cleansing, the hold (1) to be thoroughly washed with an acid solution of bichloride of mercury 1 to 800 (mercury 1 part, hydrochloric acid 2 parts, water 800 parts), applied under pressure to all surfaces by means of a hose ; (2) by sulphur dioxide, 10 per cent, per volume strength, for twenty-four hours. 2. Steerage and Forecastle. When possible to obtain it (a) The steerage and forecastle shall be disinfected by steam ; the temperature in all parts of these compartments to be not less than 100 C. for not less than thirty minutes after such temperature has been reached. (6) When steam cannot be obtained these compartinents shall be treated in the same manner as required in the disinfection of the empty hold. 3. All bedding and furnishings of the steerage and forecastle to be left in place during the disinfection by steam. If steam disinfection of steerage is not used, such articles must be removed under the strictest sanitary precautions for disinfection by steam or burning. 4. The bedding, fabrics, and carpets should be removed and disin- fected by steam or by boiling. After thorough mechanical cleansing the woodwork and all other exposed surfaces shall be washed with an acid solution of bichloride of mercury 1 to 1000, or a 3-per-cent. solution of" pure carbolic acid. Fabrics which cannot be removed shall be thoroughly saturated with a solution of bichloride of mercury 1 to 1000, or a 3-per- cent, solution of pure carbolic acid. 5. The water ballast of a vessel coming from a cholera-infected port should be discharged at sea, or, if discharged in fresh or brackish water, must be previously disinfected. The tanks to be flushed and refilled with sea-water or disinfected. 6. For a wooden vessel the treatment is as above, except that ex- posure of the hold and living-apartments to sulphur dioxide, 10-per-cent. volume, must precede the other treatment. This exposure must be, for the hold, forty-eight hours, and for living-apartments twelve hours. 7. All solid ballast to be discharged or disinfected previous to dis- infection of hold. All ballast discharged in fresh water to be disinfected by saturation with, or immersion in, an acid solution of bichloride of mercury 1 to 800. Clear, hard, close-grained rock may be permitted to remain on board, but only after disinfection by immersion in an acid solu- tion (1 to 800) of bichloride of mercury. Ballast removed from vessels must not be taken from the quarantine station. 472 TEXT-BOOK OF HYGIENE. ARTICLE VI. DETENTION OP PASSENGERS ON ACCOUNT OF CHOLERA. 1. The people detained shall be inspected by the physician twice daily, and be under his constant surveillance, and no intercourse will be allowed between different groups while in quarantine. 2. No direct communication shall be allowed between any person detained in quarantine and any one not in quarantine, except through the quarantine officer or, by his order, through his agents. 3. The water- and food- supply will be strictly guarded to prevent contamination, and issued to each group separately. 4. Food of a simple character, sufficient in quantity, thoroughly cooked, shall be issued to those detained in quarantine. No fruit shall be permitted. 5. Cleanliness of quarters and of persons shall be enjoined and enforced daily. Disinfection shall be used where there is any possibility of infection. 6. Water-closets, urinals, privies, or troughs shall be provided, and their contents disinfected before they are discharged, 7. In any group in which cholera appears, the sick will be imme- diately isolated in hospital, and the remaining persons in the group shall be bathed and their effects be disinfected ; then removed to other quarters, if possible, and the compartment disinfected. 8. No direct communication shall be allowed between the physician and attendants of the hospital and those detained in quarantine. No persons shall be discharged from quarantine until five days have elapsed since the last exposure to infection and a final disinfection of such effects as were taken to barracks. No convalescent from cholera shall be discharged from quaran- tine until after a sufficient time has elapsed to insure his freedom from infection. 1 9. The bod} r of no person dead of cholera shall be allowed to pass through quarantine. The body should be cremated if practicable. If not, it should be wrapped, without preliminary washing, in a sheet satu- rated with a solution of bichloride of mercury 1 to 500, and buried, surrounded by caustic lime. ARTICLE VII. DISINFECTION OF PERSONAL EFFECTS OF PASSENGERS AND CREW AND CARGO. 1. Clothing, bedding, and articles not injured by steam shall be disinfected (a) By exposure to steam at a temperature of 100 to 102 C. for thirty minutes after such temperature has been reached. 1 To be determined by bacteriological examination. DOMESTIC QUARANTINE. 473 (6) By boiling for fifteen minutes ; all articles to be submerged, (c) By a thorough saturation in a solution of bichloride of mer- cury 1 to 1000, and allowed to dry before washing. 2. Articles injured by steam (rubber, leather, etc.) and containers, to the disinfection of which steam is inapplicable, shall be disinfected by thoroughly wetting all surfaces with a solution of bichloride of mercury 1 to 800, or a 5-per-cent. solution of carbolic acid, and allowed to dry in open air. 3. Cooking and eating utensils, by immersing in boiling water or steam. 4. All rags and old textile fabrics used in the manufacture of paper, and all old gunny, old jute, etc., fit only for remanufacture, gathered, col- lected, packed, or handled in any port or place where cholera (cholerine) or yellow fever exists, or where small-pox or typhus fever prevails in epidemic form, and for thirty days after the port or place shall be officially declared free from such diseases or epidemic, shall be denied entry into any port of the United States. 5. No rags or old textile fabrics used in the manufacture of paper, or articles enumerated in the preceding paragraph, which have not been disinfected in accordance with Article "VII, paragraph 3, of the " United States Quarantine Regulations for Foreign Ports," shall be admitted into the United States. (Old jute bags, old cotton bags, old rope, new cotton and linen cuttings from factories, not included.) ARTICLE VIII. TREATMENT OP VESSELS INFECTED OR SUSPECTED OF BEING INFECTED WITH YELLOW FEVER. 1. Where practicable, at once remove the sick to hospital ; remove and isolate all persons not required for the care of the vessel. 2. If the hold is deemed infected, there shall be a preliminary dis- infection as hereinafter provided. 3. The bilge should be cleansed with sea-water, if possible, before disinfection, and the hold rendered mechanically clean. 4. All ballast, except close-grained, hard rock, must be discharged. This may be retained aboard if disinfected by immersion in an acid solu- tion of bichloride of mercury 1 to 800. 5. After discharge or disinfection of ballast the vessel should be disinfected. 6. If it is so stowed as to admit of disinfection, the cargo and the hold may be disinfected without breaking bulk, except to such a degree as to render disinfection practicable. It shall be as follows : 474 TEXT-BOOK OF HYGIENE. Holds to be treated with sulphur dioxide, 10-per-cent. strength per volume, forty-eight hours' exposure for iron vessels, seventy-two hours' exposure for wooden vessels. 7. Empty holds to be disinfected as follows: (a) If of iron, by sulphur-dioxide gas, 10-per-cent. strength per volume, for twelve hours' exposure, followed by washing with an acid solution of bichloride of mercury 1 to 800, applied under pressure to all surfaces by means of a hose. (b) If of wood, by the same methods as the preceding, save that exposure to sulphur-dioxide gas shall be for forty-eight hours ; air-strnkes to be open. 8. Cabin, forecastle, etc., after mechanical cleansing, to be first treated with sulphur dioxide, not less than 6-per-cent. strength per vol- ume, twenty -four hours' exposure. Then (after cleansing with water, if desired) wash all exposed surfaces with a solution of bichloride of mer- cury 1 to 800, or 3-per-cent. pure carbolic acid. 9. Clothing, bedding, and all fabrics which can be removed, not injured by steam, shall be disinfected (a) By exposure to steam at a temperature of 100 to 102 C. for thirty minutes after such temperature has been reached. (6) By boiling for fifteen minutes ; all articles to be submerged. (c) By a thorough saturation in a solution of bichloride of mercury 1 to 1000, and allowed to dry before washing. 10. Articles injured by steam (rubber, leather, etc.) and containers, to the disinfection of which steam is inapplicable, shall be disinfected by (a) thoroughly wetting all surfaces with a solution of bichloride of mercury 1 to 800, or a 5-per-cent. solution of pure carbolic acid, and allowed to dry in open air; or (b) by exposure to the sulphur fumigation, in cabin, forecastle, or hold. 11. The personnel of the vessel shall be detained five days from completion of the disinfection. 12. If the vessel has been disinfected under the supervision of an accredited medical officer of the United States at the port of departure, the period of quarantine may date from completion of such disinfection, and shall not be less than five days. ARTICLE IX. PASSENGER TRAFFIC. Passenger traffic may be allowed during the qiiarantine season from any port infected with yellow fever to any port of the United States south of the southern boundary of Maryland, under the following con- ditions : (a) Vessels to be of iron and clean immediately prior to taking on passengers. DOMESTIC QUARANTINE. 475 (6) The vessel must lie at moorings in the open harbor and not ap- proach the wharves, nor must the crew be allowed ashore at the port of departure. (c) All passengers and crew must be immune to yellow fever, and so certified by the United States medical officer. 1 (d) All baggage which has not been disinfected at the port of de- parture by the United States medical officer, or which -is not in bond for points north of the southern boundary of Maryland, shall be disinfected at the quarantine at the port of arrival ; no bedding or household effects to be allowed to enter. ARTICLE X. MISCELLANEOUS. 1. The treatment of vessels infected with typhus fever shall be the same as that' prescribed for yellow fever. 2. The detention of passengers and crew for small-pox and typhus fever shall cover the period of incubation of the disease, the time of detention to commence from the date of last exposure ; typhus fever, not less than twenty days ; small-pox, not less than fourteen days. 3. Vessels detained at any national quarantine will be subject to such additional rules and regulations as may be promulgated from time to time by the Supervising Surgeon-General. 4. The following is the form of certificate which shall be issued to the vessel by the health officer when she is released from quaran- tine : 189. I CERTIFY that , of , from , has in all respects complied with the quarantine regulations prescribed by the Secretary of the Treasury, and that in my opinion she will not convey quarantinable disease. Said vessel is this day granted free pratique. "~~> Health (Quarantine) Officer, Port of . ARTICLE XI. INSPECTION OP STATE AND LOCAL QUARANTINES. In the performance of the duties imposed upon him by the act of February 15, 1893, the Supervising Surgeon-General of the Marine-Hos- pital Service shall, from time to time, personally or through a duly- detailed officer of the Marine-Hospital Service, inspect the maritime quarantines of the United States, State and loc^.1, as well as national, for the purpose of ascertaining whether the 'quarantine regulations prescribed by the Secretary of the Treasury have been or are being complied with. 1 The evidence of immunity which may be accepted by the sanitary inspector is : First Proof of continued residence in an endemic focus of yellow fever for ten years. Second. Proof of previous attack of yellow fever. 476 TEXT-BOOK OF HYGIENE. The Supervising Surgeon-General, or the officer detailed by him as in- spector, shall at his discretion visit any incoming vessel, or any vessel detained in quarantine, and all portions of the quarantine establishment, for the aforementioned purpose, and with a view to certifying, if need be, that the regulations have been, or are, being enforced. ARTICLE XII. CANADIAN AND MEXICAN FRONTIERS. 1. When practicable, alien immigrants arriving at Canadian and Mexican ports, destined for the United States, shall be inspected at the port of arrival by the United States consular or medical officer, and be subjected to the same sanitary restrictions as are called for by the rules and regulations governing United States ports. 2. Inspection cards will be issued, by the consular or United States medical officer at the port of arrival, to all such alien immigrants, and labels affixed to their baggage, as is required in the case of those coming direct from foreign ports to any 'port of the United States. 3. Whenever alien immigrants are not inspected at the port of arrival by the United States consular or medical officer, they shall enter the United States through certain designated places on the frontier, where they shall be inspected for the purpose of preventing the intro- duction of quarantinable disease. This inspection shall be held by daylight. 4. If any person be found suffering from a quarantinable disease, or presumably infected, he shall be denied entry so long as danger of conveying the infection exists. 5. Any baggage or other effects believed to be infected shall be refused entry until made safe by a proper disinfection. 6. Persons coming from localities where small-pox is prevailing in epidemic form shall not be allowed entry without vaccination, unless they are protected by a previous attack of the disease or a recent successful vaccination. 7. Persons coming from localities where typhus fever prevails in epidemic form shall not be allowed entry until they have been away from such locality fonrteen days and their baggage disinfected. 8. During the quarantine season persons coming from places where yellow fever prevails will not be permitted to enter until they have been away from such locality five days and their baggage has been disinfected. But persons immune to yellow fever will not be detained. 9. No common carrier which is infected, or suspected of being infected, shall be allowed to enter the United States until after such measures have been taken as will render it safe. 10. Articles of merchandise, personal effects, etc., which are capable MANAGEMENT OF A QUARANTINE STATION. 477 of conveying infection, and which are presumably infected, shall not be allowed entry into the United States until after disinfection. 11. The methods of disinfection shall be those prescribed in the Rules and Regulations made for the maritime quarantines of the United States. Immigrants who, with their baggage, have been inspected at a port of the United States by a quarantine officer upon landing, will be exempt from further quarantine inspection when re-entering the United States from Canada, unless there is reason to believe that disease has developed among such immigrants since such landing and inspection. It is the intention of the act of February 15, 1893, under which these regulations were framed, to have them act uni- formly and without discrimination against any place, and at the same time to not interfere with the operation of any additional regulations imposed by State or local authority. MANAGEMENT OF A QUARANTINE STATION. Inspection. Upon the arrival of a vessel at a quarantine station, during the active quarantine season, she should be boarded without delay, and the following general routine fol- lowed, with such modifications as may be demanded by the local conditions or dictated by the experience of the quarantine officer. In the event of the arrival of several vessels at the same time, they should, as a rule, be boarded as nearly as pos- sible in the order of their arrival, the rule of " first come, first served " being observed ; though it may be remarked that, in the event of the arrival, at nearly the same time, of a vessel carrying passengers and one carrying cargo only, there will usually be little opposition on the part of ship-masters if the passenger-ship is inspected first. Arrived on board, it is well to demand the immediate attendance of the master, not only from the fact that all information must be sought from him, but to impress all concerned with the fact that the author- ity of the boarding-officer is, for the time, absolute. The master should then be required to produce for inspection his bills of health, the ship's manifest, and the crew- and passenger- lists, 478 TEXT-BOOK OF HYGIENE. if the ship carry passengers. These should be carefully scru- tinized, the number of crew and passengers being noted or borne in mind, and note being made of any articles of cargo that come within the proscription of the regulations. All special consular certificates bearing on doubtful articles of cargo had better be looked into at this time. A careful inspection of the ship should now follow, particular attention being paid to the condition of the living-apartments of the officers and crew, as their condition of cleanliness or the reverse sometimes forms an important index to the cleanliness of the whole ship. The hatches should be removed, and such portions of the cargo as come directly under them be subjected to scrutiny. If the vessel is in ballast, the hold should be entered, explored, and mental note made of the condition of the ship's inner planking or skin, whether dry and sound or rotten and damp. If pos- sible, a limber plank should be lifted, and the condition of the bilges noted. In the comparatively inaccessible places fore and aft there will likely be found deposits- of trash and filth, and the chain-lockers should be carefully examined to see whether the cables have been properly washed prior to stowing, as there is good reason to believe that the harbor-mud of certain ports, notably Havana, is dangerous. The inspection of the ship proper completed, the inspection of persons should be entered into. Every person borne upon the ship's papers as passenger or member of the crew should be personally seen by the boarding- officer or his assistant, and no excuse whatever should be taken for an absence from this muster. Take nothing for granted, and compel the master to explain any discrepancies between the lists and the actual number presenting themselves for examina- tion. The decision must now be reached whether the vessel goes free under the regulations or is to be detained in quaran- tine. If the former, the certificate of inspection is filled out, and the master notified that he is at liberty to proceed. If the latter, the vessel is directed to a suitable anchorage, and the MANAGEMENT OF A QUARANTINE STATION. 479 yellow quarantine flag is hoisted at the foremast-head. Quaran- tine procedures proper now begin, and much depends on the nature of the disease quarantined against ; the nature and con- dition of the ship, whether light, in ballast, or loaded. If there are passengers on board, these are landed, bathed, and assigned to quarters in the barracks'. The vessel is laid alongside of the wharf and the disinfecting processes prescribed by the regula- tions entered upon. The disinfection of iron and wooden vessels, while depend- ing on the same general principles, differs essentially in detail. This is illustrated in the following article on the " Disinfection of Wooden Vessels," by Surgeon H. R. Carter, published in the "Annual Report of the Marine-Hospital Service for 1892" : SOME POINTS IN THE DISINFECTION OF WOODEN VESSELS FOR YELLOW FEVER. There are many points of difference to a quarantine officer between wooden sailing-vessels and steam-ships. The former lie longer in the ports of clearance ; the crews have communication with the shore ; there are more deserters, and consequently more men are shipped at these ports to take their places. All of these things affect a vessel's sanitary standing. The points, however, to which it is desired to call attention at present are (l)the treatment of ballast and (2) the disinfection of the hold, and both apply only to wooden sailing-vessels. 1 TREATMENT OF BALLAST. This ballast is regarded differently by different boards of health, but by all as at least " suspicious." Florida regulations require the discharge of all ballast from infected ports before a vessel is allowed to enter. If the vessel is judged infected the ballast aboard must be removed at the refuge station to which she is sent, and new ballast not from an infected port substituted if any is needed. Disinfection of ballast is not recognized. Louisiana 2 allows it to be wet in situ with bichloride solution and to remain aboard during the fumigation ; then it is considered safe (1891). 'Save schooners ami American-built square-rigged craft of small burden (brigantines and barkentines mainly), practically all sailing-vessels from yellow-fever ports come in ballast. 3 The recommendation for a ballast lighter in the report of the Louisiana quarantine physician, 1890, shows that this method was not perfectly satisfactory to him. 480 TEXT-BOOK OF HYGIENE. Savannah, which ascribes an epidemic to ballast, and Charleston, while requiring all ballast to be discharged at their own quarantine stations, yet allow " dipped " ballast from vessels that have been infected to be there discharged along with ballast from non-infected vessels, thus agree- ing to its harmlessness. A vessel of which the ballast may be infected is not allowed at either of these quarantine stations. Mobile and Mississippi ports allow " dipped " ballast to enter port, and, if need be, to remain aboard or to be discharged ashore. Is ballast often a source of infection? From Havana, yes. From Brazilian ports, if of rock, no. It depends mainly on its material and whence procured. From Havana, Cienfuegos, and some other Cuban ports comes a fairly-good white stone ; a soft, crumbly, blue rock, containing talc and mixed with clay ; and what is called by masters and in the manifest " sand," but which contains so much old plaster, broken tiles, and bricks that " rubbish " would seem a better name for it. Twice this last and once (two cases) the blue-stone ballast is be- lieved to have been the source of yellow fever in vessels at the Gulf Quarantine since 1887. Rio, Santos, and the Brazilian ports south of Para send a gneiss or granite rock, not hard for its kind, but far better than the best Cuban ballast, and a loam due to its decomposition. This is also called " sand " in the manifests, and if dry may be taken for sand ; but it is really a loam, setting like cement when wetted. It is alkaline. Few vessels for Gulf or South Atlantic ports bring this " sand," as it is objected to by most quarantine officers, and the masters of vessels are suspicious of it them- selves, and when wet it makes a very dirty ship. From Rio both kinds come from high hills or mountains across the bay from the city, and the locality is considered to be a healthy one, but in 1889 I was informed that there was yellow fever among the quarry men as bad as elsewhere. Even with what is called rock ballast there is much small stuff and dust, especialty under the hatches where it is taken in. This forms a compact mass with the larger stones under the hatches, there being fre- quently one hundred to one hundred and fifty tons of this close ballast in a vessel. The finest of it, however, is only granite sand, undecom- posed, and does not cohere with water. 1 The writer is cognizant of only one case of 3 r ellow fever (British bark Chippewa, 1890), presumably due to Brazilian ballast, and this may well have been from another source. Nevertheless, in such rock ballast 1 In 1889, when there was a very bad epidemic in Rio, the rock ballast from that port was nearly all small stuff. The government was using large rock on some public works, and the vessels took for ballast what was left on the lighters. MANAGEMENT OF A QUARANTINE STATION. 481 at the Gulf Quarantine have been found rotten boards, articles of clothing, and (once) faecal matter, all at such a depth in the ballast that they must have come aboard at the port of departure (Rio, in these instances). Ballast from Colon is, for rock ballast, the worst possible, and, if infected, the best fitted to preserve infection. It is a friable, porous stone (coral?), filled with slimy mud, a fresh fracture staining water. Many cases of malarial (Chagres) fever were seen, certainly due to work- ing in this ballast, but no yellow fever has been ascribed to it the \ :i. t four years. Probably little has been at Colon during this time. Cases of yellow fever were ascribed to ballast from Vera Cruz at the Gulf Quarantine (French ship Emil Postel, 1891). Regarding ballast from infected ports, then, as " suspicious " or " probably infected," it may be either (a) discharged or (6) disinfected. When possible, the former method is, of course, preferable on the ground of economy, the ballast being discharged by lighter or otherwise in about eight feet of water. Unfortunately, most square-rigged sailing-vessels require ballast for their own safety, especially when going from outlying refuge stations to their loading ports ; and while ballast-logs may be sul>- stituted in certain cases, yet in many others, the majority, they are inap- plicable. It is, therefore, in general, impossible to leave such a vessel empty of all ballast at a refuge station. Enough close-grained, picked rock (no small stuff or trash being allowed) to trim the vessel and render her safe may be disinfected and retained aboard. This disinfection is accomplished by dipping each piece in a solution (acid) of HgCl 3 , 1 to 800 or 1000, as it is trimmed in the vessel's hold. The rock is immersed completely in the solution, and stays wet with it some time, besides being continually wetted by the solution running down from those piled on it. Although some boards of health will not allow any ballast from an infected port or vessel to enter their jurisdiction, yet it is believed that this dipped stone, hard and clean, is safe. Certainly, if washing a wooden, more or less splintered keelson with bichloride solution renders it safe to enter port with the vessel, the immersion of a granite rock in the same solution should give it, the rock, the same immunity. Indeed, the risk of conveying infection by picked rock, even without the disinfec- tion, must be exceedingly small. This is not the slow process it may seem, but is obviously slower than wetting the ballast with a hose as it lies, and a number of experi- ments were made at the Gulf Quarantine by wetting rock ballast with bichloride solution, opening the pile and testing individual stones for mercury. The solution was served through a 1^-inch hose by a strong steam-pump under full pressure, and observations were made aboard the ships Sardinian, Chrysolite, Prince Regent, and Curlew, and barks 31 482 TEXT-BOOK OF HYGIENE. President, Mabine, and others. In every case stones were found some part of which gave no reaction for mercury. As a rule, the parts in con- tact with other stones had been wet, while the parts not so in contact quite frequently did not show the reaction. A consequence of this is that where ballast is first fumigated and then wet down with bichloride solution there is some probability of the S0 3 reaching the parts of the stones not wet by the bichloride. This is less apt to take place if the fumigation follow the wetting down. It seemed as if the liquid followed certain paths in passing through the ballast, and after a certain amount of solution had been used no pro- portionate increase of wetting was observed by increasing the use of the solution. In these experiments the solution was used considerably in excess of what is usually used in wetting down ballast. Letters from masters of vessels which had had their ballast so treated elsewhere state that the ballast (rock and fine stuff) was, after the process, in good condition for handling except near the surface and next the keelson ; that no sand was carried into the bilge, and that " most of the fine stuff was as nice and dry as if the ballast had not been wet down." The same statements have been made verbally by several masters of vessels. It seems doubtful, then, if it be possible to certainly wet all of a vessel's rock ballast in situ by an amount of water short of submerging it, and that, if the ballast be infected, this method is less sure than that of dipping. Also, if ballast be thoroughly wetted, it is obvious that much sand must pass through the ceiling, stopping the limbers, fouling the pumps, and doing a certain amount of damage to the vessel, and requiring con- siderable work of the crew to correct it. Where this method was tried with sand it seemed to wet all of it ; at least every piece selected in the two vessels experimented on yielded the mercurial reaction. The sand was leveled so as to be as thin as possible, ditches dug across the hold, and then filled with the solution. After this soaked in, the ridges were turned into the ditches and the place where the ridges had been ditched, and these filled with solution of bichloride. To wet the sand thoroughly required from one-twentieth to one-twelfth of its weight of water. Colon stone is probabty not disinfected by immersion in the solu- tion of bichloride unless the time of immersion be considerably prolonged hours or days ; nor was it ever judged safe to attempt to disinfect the rubbish ballast from Havana. Of course, the ballast is to be disinfected as far as possible in situ before discharging any, when it is believed that moving it will endanger MANAGEMENT OF A QUARANTINE STATION. 483 the workers. But wet ballast is exceedingly disagreeable to handle and is injurious to the vessel, and, indeed, all work about a presumably infected vessel should be done by the acclimated quarantine crew. DISINFECTION OF HOLD. In 1888, 1889, and 1890 a series of rough experiments were made at the Gulf Quarantine to determine the penetrating power of S0 3 in suf- ficient amount to destroy animal life ants and cockroaches. These were made in the holds of vessels undergoing disinfection, so as to be under the same conditions as those in which the gas was used in practice. These cannot be given in detail here, but they showed that a film of water (sea-water) from three to five inches thick presented such a barrier to the passage of the gas that in forty-eight hours it would not destroy insect life beyond it; that clothes soaked in sea- water thick enough to stay wet were equally impenetrable, while the same clothes dry allowed insects to be killed within them ; that rotten pine-wood, if reasonably dry, was penetrated four inches with the grain and less than two inches across the grain ; that this same wood soaked in sea-water was impervious for even one inch with the grain. Dr. Kinyoun informs me that a 10-per-cent. atmosphere of SO 2 (10- per-cent. volume) will destroy certain micro-organisms through six inches of rotten wood containing 16 per cent, of moisture, I presume, with the grain. Now, in the hold of a vessel rotten wood is most apt to be found, if anywhere, in the timbers in the ill-ventilated spaces between the skin and ceiling, at the ends of the deck beams, at the water-line near the stern, but in every case between the skin and ceiling. In spite of air-strakes and ventihitors, the communication between these spaces and the open hold is very meagre, and is rendered still more so by the " stop waters " in all American vessels, pieces fitted in between the timbers to keep the bilge-water from splashing up on the cargo when the vessel lays over in sailing. Obviously, then, if the hold of a vessel be infected the infection is most probably in the rotten wood, a favorite nidus in ill-ventilated spaces, and it is ditlicult to reach. It has been the habit to use a large amount of bichloride solution and to leave it in the vessel until she leaves quarantine, so as to splash about as she rolls and so.ik into her wood as thoroughly as possible. Nevertheless, it is obvious that no liquid can be depended on to reach and saturate all parts of the woodwork under the ceiling. A gaseous disinfectant is necessary if there be infection in these places, and the problem is to make it eflicient. After opening every air-strake, they are generally closed by battens on arrival in quarantine, the main 484 TEXT-BOOK OF HYGIENE. dependence for reaching these spaces must be by the cracks between the planks in the ceiling. Now, if the vessel be fumigated immediately after she is washed down with bichloride solution, and the washing is done as it should be, all of these cracks and all of the small interstices, where beams, etc., come together, are filled by films of this solution, through which this gas cannot pass, or passes with difficulty, and the places which most need disinfection cannot get it. This to me seems a more serious objection to using the bichloride solution before fumigating, in wooden vessels, than the fact that HgCl 2 is partially converted into Hg 2 Cl 3 by the SO 3 , although this certainly occurs in pans holding bichloride in solution exposed in the hold of a vessel undergoing fumigation. Also, to enable the gas to diffuse itself through the cracks into these spaces in sufficient proportion to be efficient as a disinfectant, it is necessary to have it in the hold a considerable time. At the Gulf Quar- antine the hold was closed for forty-eight hours, and occasionally seventy- two hours. This w,as done to allow for this diffusion, and not because it was believed that so long a contact of the gas with any infecting organ- isms was desirable. It seems right to state here that infection of the hold of a vessel, not meaning the ballast, is not common in vessels which have the houses on deck, and the contents of the hold, the ballast, is less commonly infected than the dunnage of the forecastle and cabin. To determine what part of a vessel is infected, beyond a mere prob- ability, is not usually possible ; indeed, to determine if a vessel be " prob- ably infected " is at times far from easy. Officially this is determined by the regulations of the quarantine station or port of entry, but a vessel may be officially judged infected and (rightly) submitted to disinfection when, in point of fact, the prob- ability of her being infected is slight; and (for Middle Atlantic ports) the converse may occur. The fact of a vessel having had yellow fever aboard, especially if only at the port of clearance and not en route, may not be sufficient to class her as " probably infected." The circumstances of the attacks may be such as to show that they were contracted ashore, and that the sick men did not contaminate the vessel ; or there may be evidence to show that, although there was a source of infection aboard the vessel, it is no longer existing. For an instance of the first, among many instances, the American ship Fawne had six cases of yellow fever developing aboard her while at Rio in 1891, but in every case it developed in seamen who, the log showed, had returned from shore less than thirty-six hours before, and there had been no development of fever among a considerable number, TREATMENT OF YELLOW-FEVER VESSELS. 485 twelve or fourteen, of unacclimated seamen living in the same forecastle and working over every part of the ship for about fifty days since the last case aboard. From this vessel the sick were sent to hospital the first day of their sickness, with all of their loose dunnage with them. No supplies taken aboard, no men shipped, and only the master went ashore after the fever developed. This vessel was probably not infected at any time. As an illustration of the second, far less common than the first, the British ship Prince Frederick was infected at Rio in 1889. A number of cases thirteen, I think developed aboard her under con- ditions which showed that they were contracted aboard, i.e., in men who had had no recent communication ashore, and one case en route. She came up short-handed to Barbados, having en route destroyed some dunnage that of the dead and aired all of the rest, keeping it on lines in the sun all of every day when possible ; cleaned and ventilated the houses above decks, and ventilated the hold. The weather the whole time was bright, with light winds. At Barbados the crew was strength- ened by shipping new men, among them seven English lads, fresh young fellows from 16 to 21 years old, who had never been south before, the most perfect temoines for yellow fever, yet no case developed among them, even when they cleaned ship. This vessel undoubtedly had a source of infection aboard, but was freed from it, probably, in consequence of the ventilation and other measures adopted. If there be dunnage packed away aboard which was infected when packed, no time-limit can be relied on for removing the infection, while persistent airing in bright weather will probably do so. Even washing in cold water, as sailors do, seems to be sufficient to disinfect fabrics from yellow fever. Several cases are known where aired or washed clothing was handled with impunity by a number of unacclimated persons, from which yellow fever had been contracted by those who unpacked or washed it, and no case of infection from well-aired clothing has ever been known to the writer. Moisture seems necessary for the infection to keep its efficiency. It is not, of course, intended that airing, etc., should ever be relied on for the disinfection of fabrics ; only to show that some vessels may clear themselves of infection by this method and ventilation. TREATMENT OF YELLOW-FEVER VESSELS. It is fortunate that vessels from yellow-fever ports rarely have any considerable number of passengers on board, and that 486 TEXT-BOOK OF HYGIENE. our efforts have therefore to be directed only to the cleansing of the ship, the care of those actually sick with the disease at the time of arrival, and the detention, under observation for a period of five days, of those exposed to the infection. The cleansing of the ship, whether of wood or iron, is specifically treated of in the regulations ; the disinfection of the cargo presents few difficulties, as the cargo is usually either sugar or coffee, gen- erally packed in bags, and admitting of thorough disinfection by the application of sulphur dioxide in the strength and for the time prescribed in the regulations. Several years ago the Louisiana State Board of Health issued a circular to shippers recommending that all cargoes of sugar and coffee be stowed with a shaft or tunnel under each hatchway, reaching from the upper tiers of the cargo to the keelson of the vessel. This shaft admits of the entrance of the sulphur-hose, and the gas, forced in under pressure, has free access to the envelopes of every package, which it penetrates to the depth of three-quarters of an inch or more, thus insuring thorough disinfection of the cargo without the necessity of breaking bulk, and at a minimum of time and expense. The sick should be at once carried to the infected hospital, if their condition permit it, and the remainder of the crew and passengers inspected twice daily until the time of danger is passed and the vessel is discharged from quarantine. Vessels from yellow-fever ports generally arrive at quar- antine stations either light or in ballast. The treatment of these vessels is so fully dealt with in the foregoing article of Surgeon Carter that further comment is unnecessary. TREATMENT OF CHOLERA VESSELS. In the event of the arrival of a ship actually infected with Asiatic cholera, or suspected of such infection, a much more difficult problem confronts the quarantine officer, for the condi- tions differ widely from those obtaining in the case of the yellow- fever ship. In a majority of cases the cholera ship carries a TREATMENT OF CHOLERA VESSELS. 487 large number of passengers, a great majority of whom belong to the immigrant class, and the difficulty of handling these is largely increased by the carelessness of their personal habits, their ignorance and disregard of the first laws of personal hygiene, and the discomfort, crowding, and bad sanitary con- dition of their quarters on board ship. Here many sources of danger must be looked into, and it is almost certain that a disregard of any one of them will be followed by a terrible retribution in the shape of new outbreaks of the disease. The first thing to be done in the treatment of a cholera- infected ship is to remove her human freight, and this should be done as rapidly as is consistent with safety. The occupants of the compartment of the ship in which cholera has appeared should receive our first and most careful attention. They must be landed at once, bathed with all possible precaution and thoroughness, furnished with clean, sterile clothing, and isolated in the barracks and regarded as especially dangerous. Those actually sick with the disease should be at once carried to the contagious hospital, and those sick with any complaint whatever isolated in the suspect hospital pending the determination of the actual nature of their disease. The foregoing applies particularly to the steerage passen- gers. The question of the treatment of the cabin and saloon passengers is one that will call for all the tact and ingenuity of the quarantine officer, and even then he will be liable to savage criticism and censure through the friends of the cabin passen- gers detained. It must be remembered that these passengers are luxuriously lodged and catered for with every delicate atten- tion that ingenuity and long experience, sharpened by active competition, can suggest. On board ship they are most care- fully guarded from intrusion on the part of the steerage passen- gers, and, in fact, are as nearly on a separate ship as possible. Is it always necessary to subject these people to the inconveni- ences and possible hardships that are inseparable from a deten- tion in quarantine barracks'? The answer is that each case 488 TEXT-BOOK OF HYGIENE. must be decided on its individual merits, and much will depend on the extent to which the ship seems infected, the seeming source of the infection, and the facilities which exist on board ship for maintaining a sharp line of demarkation between the steerage and saloon. If, on investigation, it seem that the choleraic outbreak is due to infected food smuggled on board by the emigrants, to infection probably brought aboard in the hand-baggage of the same class of passengers ; if, in fine, it would seem to be due to conditions limited to the steerage, it might seem to be the part of wisdom to leave the cabin passengers in their luxurious quarters while the processes of disinfection and detention were in progress. If, on the contrary, the infection seem to be due to a polluted ship's water-supply; if there have been any cases of diarrhceal disease among the cabin passengers ; if the infec- tion seem to be distributed equally to the steerage and to the saloon, then all must be landed alike, and undergo barrack detention, at least, until the disinfection of the ship is thoroughly complete. The barracks for the cabin passengers must, of course, be of a different character from those provided for the steerage. They must be subdivided into small rooms, and, instead of bunks, must be furnished with comfortable cots, bedding, and simple, but neat and efficient, toilet facilities. A separate kitchen and table must be provided for this class of passengers, and the whole situation may be summed up by saying that the relative difference on shipboard should be preserved on shore during the detention in quarantine. SPECIAL MEASURES AGAINST CHOLERA. Other features of quarantine administration are well ex- pressed in the following extract from the editorial pages of the Philadelphia Medical News of October 15, 1887, showing the measures necessary to extinguish an incipient epidemic of cholera and to prevent its spivad. Such measures are as follow: SPECIAL MEASURES AGAINST CHOLERA. 489 (a) Speedy recognition and isolation of the sick ; their proper treatment ; absolute and rapid destruction of the infectious agent of the disease, not only in the dejecta and vomit, but also in clothing, bedding, and in or upon whatever else it finds a resting-place. (6) The convalescents should remain isolated from the healthy as long as their stools possibly contain any of the infecting agent ; before mingling again with the well they should be immersed in a disinfecting bath, and afterward be clothed from the skin outward with perfectly- clean vestments, which cannot possibly contain any of the infectious material. (c) The dead should be well wrapped in cloth thoroughly saturated in a solution of corrosive sublimate (1 to 500), and, without delay, cortege, or lengthy ceremonial, buried near the place of death in a deep grave, remote as possible from water which may, under any circum- stances, be used for drinking, washing, culinary, or other domestic pur poses. (Cremation, of course, is by far the safest way of disposing of cholera cadavers.) (d) Those handling the sick or the dead should be careful to dis- infect their hands and soiled clothing at once, and especially before touch- ing articles of food, drinking, or culinary vessels. (e) In the case of maritime quarantine, the well should be disem- barked and placed under observation in quarters spacious enough to avoid crowding, and so well appointed and furnished that none will suffer real hardships. (/) Once having reached the station, those under observation should be separated in groups of not more than twelve to twenty-four, and the various groups should, under no pretext, intermingle. The quar- ters for each group should afford stationary lavatories and water-closets in perfect working condition, adequate to the needs of the individuals constituting the group, and supplied with proper means of disinfection. There should be a bed raised above the floor, proper coverings, and a chair for each member of the group, each person being required to use only his own bed. There should be a common table of sufficient size to seat around it all the members of the group, who should be served their meals from a central kitchen, and with table-furniture belonging to the station and cleaned by the common kitchen scullions. (g) Drinking-water, free from possible contamination and of the best quality, should be distributed in the quarters of each group as it is needed, and in such a manner that it is received in drinking-cups only. There should be no water-buckets or other large vessels in which hand- kerchiefs, small vestments, children's diapers, etc., can be washed by the members of any group. 490 TEXT-BOOK OF HYGIENE. (h) Immediately after being separated into groups in their respect- ive quarters, every person under observation should be obliged to strip and get into a bath (a disinfecting one is preferable), and afterward be clothed with fresh, clean vestments from the skin outward. Every article of clothing previously worn should be taken away and properly disin- fected. (i) Then all of the personal effects should be at once removed to a separate building, washed (if possible), and thoroughly disinfected, or, if necessary, destroyed. After disinfection they should be temporarily returned to the members of groups, when occasion requires a further change of clothing. (jfc) Under no circumstances whatever should washing of clothing by those under observation be permitted. All used clothing should be first thoroughly disinfected (by boiling, when possible), and then should be cleansed, the disinfection and washing being done by a sufficiently trained and absolutely reliable corps of employe's supplied with adequate appliances. (I) All those under observation should be mustered in their own quarters, and be subjected to a close medical inspection, while on their feet, at least twice every day, in order to discover and isolate, as soon as. possible, new cases which may develop ; and, of course, the clothing and bedding of these new cases should be treated without delay in the manner already mentioned. In the mean time, a watch should be set over the water-closets for the purpose of discovering cases of diarrrhcea, and, when discovered, such cases should be temporarily separated from the rest. They should receive judicious medical attention at once, and precautions should be taken as if they were undoubted but mild cases of cholera. (m) The quarters should be kept thoroughly clean, and every sur- face upon which infectious material could possibly be deposited, includ- ing the floors, should be washed with a strong disinfectant twice daily, and oftener when necessary. Evacuations from the bowels should be passed into a strong disinfectant ; the hopper of the closet should be then flushed and finally drenched with a quantity of the same disin- fectant. (n) For the proper attention to the sick, there should be two or more competent and experienced physicians, assisted by a sufficient corps of intelligent and efficient nurses, with hours of duty so arranged that a physician, with a sufficient number of nurses, shall be in constant attendance in the wards of the hospital. (o) For the prompt recognition and separation of new cases, their temporary medical attention, the proper treatment of discovered cases REGULATIONS FOR CHOLERA CAMP. 491 of diarrhoea or cholerine and of other maladies, and the immediate cor- rection of every insanitary practice or condition by constant, vigilant, and intelligent supervision, there should be at least two or more compe- tent and experienced physicians, with hours of service so arranged that a pli3 T sician is on duty night and day among those under observation ; and he should have, subject to his orders at any and every moment, a sufficient and efficient corps of nurses and laborers to carry out properly and promptly his directions. (p) In order to prevent the intermingling of the various groups, to enforce obedience and order, and to make it absolutely impossible for the quarantined and their personal effects to have any communication with the exterior, a well-organized and sufficiently large police corps should patrol the borders of the stations and the buildings day and night. (q) Any group among whom there have developed no new cases of cholera or of choleraic diarrhoea, during the preceding eight or ten days, may be regarded as harmless, and allowed to leave quarantine after each one is finally immersed in a disinfecting bath and re-clothed with clean garments from the skin outward, the garments removed being destroyed or thoroughly disinfected and cleansed, as already indicated. As yet no reference has been made to the crew, ship, and cargo. What has been said of the treatment of those under observation applies to every one of the ship's inhabitants. The observation, isolation, and cleansing of the crew and their effects could safely be performed aboard ship if necessary. The ship should be thoroughly cleansed and disin- fected, particular attention being given to the quarters of the emigrants and crew. The following general regulations were promulgated for the government of camps and barracks for the detention of cholera suspects during the summer of 1892: REGULATIONS FOR CHOLERA CAMP. (Prepared in the Marine-Hospital Bureau.) The surgeon in command of the quarantine camp to have absolute authority over the police and sanitary regulations of the camp, and to see that they are obeyed. Camp to be divided into two divisions, detention and hospital. Former for housing of suspected cases and well per- sons from infected localities and the latter for treatment of sick. 492 TEXT-BOOK OF HYGIENE. DETENTION CAMP. 1. Persons destined for this camp to be assigned to specific quarters in tents. First to be subjected to disinfecting bath, and clothed afterward with fresh vestments. Not to leave this camp except by permission or order of surgeon in command. 2. Persons in detention camp to be inspected twice daily or oftener by medical officer or assistant, while standing, to ascertain any new cases which may develop. 3. New cases of cholera in detention camp to be immedi- ately transferred to hospital camp for treatment, and all their effects disinfected, as well as the tent in which they may occur. 4. Guards to patrol detention camp night and day, to pre- vent intercourse between the two divisions of the camp. 5. Water-supply for entire camp to be boiled for drinking. To be dealt out to each person in cups or glasses for potable purposes. May be acidulated with diluted hydrochloric acid under supervision of a medical officer. 6. If there be room, the detention camp to be segregated into divisions of not more than twenty persons. No intercom- munication should be permitted between the groups. 7. All clothing removed from persons entering detention camp to be subjected to steam heat (unmixed with air), not less than 100 C. (212 R), for one-half hour, or boiling for one hour. Leather and rubber goods to be immersed in 3-per-cent. carbolic-acid solution until thoroughly saturated. 8. The washing of clothing not to be permitted by the detained persons under any pretext. After above disinfection, all laundry-work to be then done by the force of employes. The clothing of detained suspects should be kept in separate building after disinfection, and re-issued as required for change. 9. Cleanliness and disinfection of quarters and person to be enjoined and enforced daily. Disinfectants to be used where there is any possibility of infection. HOSPITAL CAMP. 493 10. At the expiration of five days, if no case of cholera or choleraic diarrhoea has developed in a given group segre- gated as above, those composing the group may be discharged, after a final disinfection of person and clothing. 11. All water-closets, urinals, privies, or troughs should be provided with latrines similar to those of the cholera camp, and means should be provided for their thorough disinfection before their contents are discharged into pits of unslacked lime. 12. Food issued shall be simple, thoroughly cooked, and served at stated hours. No fruit permitted. HOSPITAL CAMP. 1. Day sick-calls at 8 A.M. and 4 P.M. ; oftener, if necessary. Night call, 12 P.M., by night physician; oftener, if circum- stances require. 2. There shall be one nurse for every hospital tent, who shall be on duty in six-hour watches. Night nurses according to circumstances. Female nurses for cases occurring in that sex. Nurses should be instructed in the necessity of personal hygiene and the sources of infection. 3. Vomited matter and stools to be received into earthen vessels, and at once disinfected with 3-per-cent. solution of car- bolic acid or 1 to 500 HgCl 2 combined with 2 parts of HC1 to each part of HgCl 2 ; then thrown into a pit of unslacked lime, or discharged into the sea. 4. All soiled linen or clothing that cannot be disinfected to be immediately destroyed by burning. 5. When death occurs, body to be immediately buried, swathed in sheets saturated with 1 to 500 HgCl 2 . Place of interment to be selected to avoid contamination of water-supply. 6. No persons having personal contact with the sick or dead shall leave the hospital camp without practicing disinfec- tion, as specified above. 494 TEXT-BOOK OF HYGIENE. DANGER FROM FLIES IN QUARANTINE. In this article it has been suggested that all dejecta and vomited matters of cholera patients be received into vessels con- taining an efficient germicidal solution ; and this is not only for the reason that the said dejecta and vomited matters may infect any one who comes into inadvertent contact with them, but has an important bearing on the health of those who are resident in the neighborhood of the quarantine station. It has been abundantly proved that the ordinary house-fly is capable of con- veying in its intestinal tract, for a considerable length of time, living and active cholera spirilla. Knowing how constantly flies deposit their ordure on articles of food, it can easily be seen how great a menace to public health would be engendered by allowing stools containing the bacilli to remain without instant disinfection. The safer plan is, therefore, to not trust to subse- quent disinfection, which might be overlooked in the press of other matters, but to receive the dejecta into the germicidal solution so that no time will be lost and no chances of infection may remain. THE NATIONAL QUARANTINE SERVICE. The national quarantine stations, eleven in number, are established at points of danger where either local quarantine is defective or where, by reason of peculiar advantage in location, protection is afforded to several States by one station. These stations are as follow: Delaware Breakwater Quarantine Station, Lewes, Del. ; Reedy Island Quarantine Station, Delaware River; Cape Charles Quarantine Station, Fisherman's Island, Va, ; South Atlantic Quarantine Station, Blackbeard Island, Sapelo Sound, Georgia ; Brunswick Quarantine Station, Brunswick, Ga. ; Key West Quarantine Station, Tortugas Islands, Fla. ; Gulf Quarantine Station. Ship Island, Miss. ; San Diego Quarantine Station, San Diego, California ; San Francisco Quarantine Sta- tion, Angel Island, San Francisco Bay, California ; and Port THE NATIONAL QUARANTINE SERVICE. 495 Townsend Quarantine Station, Port Townsend, Washington. A station has been authorized by Congress and will be erected at Southport, N. C. DESCRIPTION OF THE NATIONAL QUARANTINE STATIONS ON DELAWARE BAY AND RIVER. It may prove of interest to briefly describe a national quarantine station, and -no better example can be found than the stations at Delaware Breakwater and at Reedy Island, Delaware River. These stations, while in a measure separate and distinct, are intended to work in connection with each other and to afford complete protection against the importation of contagious and infectious disease through the medium of the commerce which seeks the port of Philadelphia and the ports of entry on Delaware Bay, and situated in the States of Dela- ware, New Jersey, and Pennsylvania. At the station at Delaware Breakwater, which is situated at the mouth of Dela- ware Bay and immediately upon the point formed by Cape Henlopen, is the reservation, forty acres in extent, and sur- rounded by a substantial picket-fence ten feet in height. Within this enclosure is located the quarantine plant proper, consisting of commodious hospitals for contagious and non- contagious diseases, and barracks for the accommodation of one thousand suspects, fitted with bunks and provided with bedding and a full supply of clothing for both males and females. In connection with these barracks are a large kitchen, fully equipped with steam cooking-apparatus of the most im- proved description and a commodious mess-hall. There has been also provided a building containing a boiler for operating the pumps, a bath-house, and laundry, which latter is equipped with appliances for washing all soiled clothing and for subject- ing them to the boiling process. In this building there is also located a steam disinfecting chamber of the most modern and improved type, ami adjoining this building is a bath-house fitted with twenty shower- and two tub- baths, all provided with 496 TEXT-BOOK OF HYGIENE. hot and cold water. An artesian well has been sunk, capable of supplying twenty thousand gallons of water per day, and this water is raised by a powerful pump to elevated tanks, and from these distributed to the barracks, kitchens, hospitals, laundry, and bath-house. Latrines are provided and furaishecf with iron containers holding a strong disinfecting solution, and provision is made for emptying these containers into a sewer, which, in turn, empties into a sewer common to the bath-house and laundry, which discharges into the sea. The danger of soil contamination by alvine discharges is reduced to a minimum, and the water-supply likewise protected. Outside of the fence is a large brick house, which furnishes executive and administrative offices and quarters for the medical officers on duty at the station. In front of the executive building is a lofty flag-staff, which affords the means for communicating by signals with vessels in quarantine and arriving in the offing. Within a few hundred yards of the reservation is a long iron pier, which affords ample facilities for the landing of pas- sengers. Situated fifty-five miles above the Breakwater, and forty- five miles from Philadelphia, is the Reedy Island Quaran- tine Station, on and near the island of that name. Upon the island itself are situated the residence of the medical officer, quarters for employes, and a cottage hospital. A boat-house is connected with the island by a gangway. The quarantine plant proper is located on a pier situated on the edge of the channel, and in thirty feet of water. The pier is two hundred feet in length, and presents a frontage of nearly four hundred feet, owing to the placing of an ice-break above and below the pier. This affords room for the accommodation of the largest vessels, and upon the wharf is situated the disinfecting plant, consisting of two steam chambers ; a sulphur-furnace, fan and engine for driving the same; tanks for disinfecting solu- tions and a pump and hose for their distribution ; a fire-pump, AIDS TO NATIONAL QUARANTINE. 497 and tanks for the storage of water for fire and steaming purposes. There are no barracks at this station, it being the plan that the vessel shall receive quarantine treatment at this point, and that the passengers shall undergo their detention in the barracks at the Breakwater station. Another national station which deserves special notice from its peculiarities is the quarantine vessel Jamestown^ which can be considered a floating quarantine station. The Jamestown was turned over to the U. S. Marine-Hospital Service by the Navy Department for quarantine use. She is one of the old- fashioned sailing-vessels of the navy, is very strongly and solidly constructed, and is one hundred and sixty-six feet long, thirty-six feet beam, and has a displacement of eight hundred and eighty-eight tons. She has been fitted for her present use by being housed in, and there have been placed on board a steam disinfecting chamber, a sulphur-furnace, tank for bichlo- ride solution, and bath-rooms. In addition to these, she has been fitted as a place of detention for two hundred and fifty to three hundred immigrants, and is in all respects a complete quarantine station, and capable of doing valuable service in smooth water. AIDS TO NATIONAL QUARANTINE. In aid of the national quarantines, sanitary inspectors are appointed by the Marine-Hospital Service at special points of danger, either in the United States or abroad. Through the State Department consular notification from foreign ports is received regularly by mail, or, in emergency, by cable, and the information thus received, and that received also from home ports, is communicated, by the Marine-Hospital Bureau, to all quarantine authorities and others, by means of a weekly publi- cation known as the " Abstract of Sanitary Reports." An important source of information concerning the move- ments of vessels in every portion of the world is the " Maritime 498 TEXT-BOOK OF HYGIENE. Register," published in New York. The United States Col- lectors of Customs are efficient aids, having-, by law, the power of search and detention of vessels, and having exceptional knowledge of the sanitary condition of the shipping at their respective ports. The Revenue-Cutter Service, a national coast patrol, gives frequent and efficient aid ; the Light-house Estab- lishment and Coast Survey render valuable assistance in locating and buoying the anchorages, and the Life-Saving Service, with its constant patrol of the coast, guards against the entry of a vessel at an unusual point. The surf-men are required to rake together and destroy dunnage and other material likely to be infected that have been thrown overboard and washed ashore from infected vessels. Finally, the Marine-Hospital Service, having, besides the quarantines, the care of the sick of the merchant vessels of the United States, with one hundred and twenty-six physicians stationed at the larger and many of the smaller ports, is ready at a moment's notice to extend in- definitely its quarantine service. NATIONAL INSPECTION OF ALL QUARANTINES. The Act of Congress approved February 15 1893, while contemplating that State and local quarantines shall not be dis- turbed in the exercise of their functions, provided said quar- antines are administered in accordance with the law and the regulations made thereunder, further provides that the rules and regulations of local quarantines shall be examined by the Surgeon-General of the Marine-Hospital Service, and also that such additional rules and regulations as may be deemed neces- sary shall be made by the Secretary of the Treasury, and shall be enforced by the State or local quarantine authorities. If the latter refuse, or are unable to enforce them, the law further provides that the President of the United States shall detail or appoint an officer for this purpose. To carry out the intent of this law all the quarantines of the United States, national, State, and local, are inspected periodically by an officer of the Marine- NATIONAL INSPECTION OF ALL QUARANTINES. 499 Hospital Service. Following are the instructions prepared for the inspecting- officers: INSTRUCTIONS TO MEDICAL OFFICERS OF THE MARINE-HOSPITAL SERVICE DETAILED TO MAKE INSPECTIONS OF STATE AND LOCAL QUARANTINES. TREASURY REGULATIONS. ***** **** In the performance of the duties imposed upon him by the act of February 15, 1893, the Supervising Surgeon-General of the Marine- Hospital Service shall, from time to time, personally or through a duly- detailed officer of the Marine-Hospital Service, inspect the mnritime quarantines of the United States, State and local, as well as national, for the purpose of ascertaining whether the quarantine regulations pre- scribed by the Secretary of the Treasury have been, or are being, com- plied with. The Supervising Surgeon-General, or the officer detailed by him as inspector, shall, at his discretion, visit any incoming vessel, or any vessel detained in quarantine, and all portions of the quarantine estab- lishment for the above-named purpose, and with a view to certifying, if need be, that the regulations have been, or are being, enforced. J. G. CARLISLE, Secretary. GENERAL INSTRUCTIONS. A. Your inspections will include all ports within your district where vessels are allowed to enter and discharge cargo, and ports which may be used as ports of call. B. A separate report will be made of each station visited. C. Visit every part of the quarantine establishment, and take necessary precautions to prevent the conveyance of contagious or infec- tious disease through the medium of your own person. D. Visit the custom-house for the purpose of ascertaining whether the regulations with regard to bills of health and quarantine certificates are being observed; also, the immigration station for any pertinent information. E. Reports of a statistical character and descriptive of the quar- antine, called for herein, need be made but once in every six months, namely, on the date neai'est the 1st of January and the date nearest the 1st of July ; but any changes that have been made since the last general report should be immediately recorded. In making your report you will follow the special instructions in their order, referring to each by number. 500 TEXT-BOOK OF HYGIENE. SPECIAL INSTRUCTIONS. 1. Describe the quarantine station, location, buildings, anchorages, etc. Give limits of anchorage for non -infected and for infected vessels ; facilities for inspection of vessels ; apparatus for disinfection of vessels and of baggage ; facilities for removal and treatment of the sick, and for the removal and detention of suspects ; mail and telegraph facilities, etc. 2. Give personnel of the station or port ; name of the quarantine officer or officers ; post-office address ; total number of officers and subordinates, etc. 3. Transmit copies of the laws under which the local quarantine is maintained, and copies of the quarantine regulations ; also describe the quarantine customs of the port as they are curried out. NOTE. There are sometimes slight, but possibly important, variations from the letter of the local regulations in the administration of quarantine. Also, local regula- tions generally allow a wide latitude to the quarantine officer, and how this latitude is used i.e., how the quarantine officer interprets the spirit of the regulations is very important. 4. State what quarantine procedures, either under printed regula- tions or by custom, are enforced at the port, in addition to the require- ments of the Treasury Department. It should also be stated whether there is undue or unnecessary detention or disinfection of vessels. 5. State whether the inspection is maintained throughout the year or for what period, and what treatment of vessels is enforced during the entire year. NOTE. Many ports on the South Atlantic coast (e.g., Charleston, Savannah, and Fernandina) require certain ballasts to be discharged in quarantine without regard to season. 6. Are vessels from other United States ports inspected ? 7. Describe quarantine procedures in the inspection of vessels, and, if infected, the treatment. Give time in quarantine (a) between arrival and commencement of disinfection, (6) time occupied by disin- fection, and (c) time after completion of disinfection of vessels until discharge. NOTE. Quick or slow handling of a vessel is of more importance commercially than the question of fees. The time lost is the vessel's heaviest expense, generally. 8. What communication is held with vessels in quarantine (nnd, before quarantine, by pilots, etc.), and how regulated? Is there any intercommunication allowed among vessels in quarantine? 9. State what will be done with a vessel infected with cholera; second, a vessel infected with yellow fever; third, a vessel infected with small-pox (said vessels carrying or not cany ing immigrants), and what THE SANITARY CORDON. 50.' conditions are regarded as giving evidence of the vessel's infection in each case. 10. State whether records are kept, at the station, of the cases of disease that have occurred during the voyage, on arrival, and during detention. 11. Transmit schedule of quarantine fees, and give other fees and expenses necessarily and usually attendant on quarantine, as tonnage, ballast, wharfage charges, etc. 12. Make a statement showing the number of vessels arriving at the port during the preceding calendar year, by months, (a) from foreign ports; (6) from foreign ports in yellow-fever latitudes via do- mestic ports ; (c) from domestic ports. Show, also, the character of the commerce carried on by the port, i.e., from what countries chiefly the vessels come, and whether in cargo, ballast, or empty. 13. State results of your visit to (a) the Custom-house; (6) the Immigration Bureau. 14. State whether, in your opinion, the quarantine facilities are sufficient to care for the shipping entering the port. 15. Name the quarantine regulations of the Treasury Department which are not properly enforced, and state specifically whether the regu- lations regarding inspection and disinfection, and particularly the period of observation after disinfection, of vessels are observed. 16. Mention any facts which, in your opinion, should be known to the Department, bearing directly or indirectly upon the quarantine service, and make such recommendations as seem proper. WALTER WYMAN, Supervising Surgeon- General M.-H. S. NOTE. Report to be written on legal-cap paper (on one side only), signed, and inclosed in this blank as a cover. INLAND QUARANTINE. Under Inland Quarantine will be described The Sanitary Cordon, Camps of Probation, Railroad Quarantine, Disinfection Stations, and Inspection Service. THE SANITARY CORDON. This consists of a line of guards, military or civil, thrown around a district or locality, either to protect the same from the surrounding country when infected, or to protect the surround- ing country from the infected district or locality. When a given locality is infected, and the 'adjacent territory is regarded 502 TEXT-BOOK OF HYGIENE. as suspicious, it may be necessary to establish a double cordon, the first one embracing the whole suspected territory at its outer edge, the second investing more closely the well-defined infected locality. After the expiration of a sufficient time to prove that the area between the cordons is not infected, or has been cleared of infection, the first cordon may be removed. Hospitals and camps of probation may be necessary adjuncts to the cordon. The most noted example of the sanitary cordon is found in the history of the plague-epidemic in Russia in 1878. A colony on the river Volga, called Wetljankaja, with a popu- lation of 1700 inhabitants, became infected with the Oriental plague, which extended to the neighboring villages. A military cordon was made to embrace all the infected district. The in- habitants of the focus of infection, Wetljankaja, were removed, property appraised for re-imbursement by the government, and the village burned. An additional cordon was thrown around Zarizin, a neighboring commercial city of importance and ter- minus of the Russian railway system. The cordons were main- tained several months, and the plague was stamped out. (See Abstract Sanitary Reports, vol. i [Bulletin's], page 78.) The sanitary cordon is the customary method of preventing the spread of epidemic disease in the eastern countries. In the United States, when yellow fever prevailed in Pen- sacola, in 1882, to the extent of 2200 cases, the navy-yard reservation, whose boundary-line is within two miles of the city limit, and with a population of about 1500, was successfully guarded by means of a cordon and non-intercourse. The following year, 1883, the navy-yard itself was infected, and a cordon was thrown around it to protect the city of Pen- sacola, and "was maintained for a period of sixty days. This cordon was under the management of the Surgeon-General of the Marine-Hospital Service, aid having been requested of the national government. The Collector of Customs of Pensacola was made the agent to execute the orders of the Marine-Hos- pital Bureau, and to the President of the local Board of Health THE SANITARY CORDON. 503 was intrusted the immediate command of the line and guards. The cordon entirely surrounded the land-houndary of the naval reservation. Its line was tour miles in length, one mile of it through a dense thicket, and was marked by blazed trees and flags. Forty men were employed as guards, an equal number being selected from each of the two political parties. Two captains were appointed, and were obliged to supervise the line night and day. The sentinel posts were furnished with tents, and two guards wore allotted to each post, taking alternate watches of four hours each. A detention or probation camp was established and placed in charge of a physician, where persons wishing to leave the reservation were obliged to pass a probationary period of twenty days. Not more than half a dozen persons were received in this camp. The government expended about $20,000 in these restrictive measures, which were entirely suc- cessful. Not one person got through the cordon line. The success was due largely to the thorough discipline maintained by the Collector and the President of the Board of Health. Yellow-Fever Cordon in Texas. In 1882, yellow fever prevailing in Mexico, along the Rio Grande, and in Browns- ville, Texas, a sanitary cordon was established by the Surgeon- General of the Marine-Hospital Service, on request of the Governor of the State, extending along the line of the railroad from Corpus Christi, on the Gulf of Mexico, inland to Laredo, on the Rio Grande. This line was one hundred and eighty miles northeast of Brownsville, the triangular territory thus hemmed in by the cordon on one side, the Rio Grande on another, and the Gulf on the third, being all suspected terri- tory, although the fever prevailed in only one corner of it, vi/., in Brownsville. All persons were detained at least ten days at the cordon before being allowed to pass northward, a period of probation to insure that no one having the disease should carry it farther north. As soon as practicable another cordon was established much nearer to Brownsville, only thirty 504 TEXT-BOOK OF HYGIENE. miles from it, the line extending from the mouth of the Sol Colorado, on the Gulf of Mexico, to Santa Maria, on the llio Grande. After a time sufficient to prove that no more fever prevailed between the two cordons, the first one was removed. Within the, second line, where the fever prevailed, chiefly in Brownsville, a hospital was established and dispensaries opened for the gratuitous treatment of all applicants. Upon the Mexican side of the Rio Grande the fever con- tinued to spread northwardly, and, in order to oppose it, still another cordon had to be established on the American side of the river, extending from Santa Maria on the south to Laredo on the north, a distance of five hundred miles. Three hundred guards, well mounted (Texan cow-boys), were employed in this cordon, and, while the disease was being stamped out in Brownsville, any further importation from Mexico was thus prevented. In Mexico the fever continued to spread until the authorities finally adopted measured similar to the above. The epidemic of yellow fever in Brunswick, Ga., in 1893, .gave rise to the necessity of establishing a sanitary cordon to protect the surrounding country from the danger incident to the panic-engendered flight of the inhabitants of that town. On account of the peculiar situation of Brunswick the difficulties to be met were very great. Not only were numerous roads to be guarded, but three water-passages from the city into the surrounding country had also to be watched. The cordon, therefore, partook of the nature of both a land and water patrol, and the difficulties were successfully overcome, and no well-authenticated instances of escape through the lines were established. Much violent language has been used concerning the hardships imposed by the sanitary cordon, but in the presence of an epidemic the authorities who are responsible need to pay more heed to the efficiency of the cordon than to individual complaints. It should be borne in mind that the sanitary cordon is not intended to bottle up all the people who are CAMPS OF PROBATION. 505 caught within an infected district. On the contrary, it is intended as a means of exit to those who will not carry with them contagious disease to the people beyond. The cordon, then, imposes simply a period of detention corresponding to the incubative period of the prevailing disease. Ample preparation must be made for housing and feeding, in camps or other quarters, persons awaiting the expiration of the detention period ; and hospitals must be provided for the treat- ment of those who develop sickness. Provision must also be made for the disinfection of suspected baggage. CAMPS OF PROBATION. Camps of probation or detention should be established with all the precision of arrangement and regard for site, water, and drainage that pertain to a military camp. Every effort should be made to make the camp as comfortable and cheerful as pos- sible, and to this latter end amusements and entertainments such as might be suggested by the campers themselves should be encouraged. Every necessity in the matter of food, bedding, and the ordinary comforts of life should be anticipated, to pre- vent any just cause of complaint. Such a natural division of the inhabitants should be made as seems desirable at the time, those of equal intelligence and refinement naturally seeking each other's company. The greatest concern is to prevent the camp itself from becoming infected. To this end no baggage should be allowed within the camp-boundary without previous disinfection ; and every refugee should be examined by a phy- sician before being admitted to the camp. No one should be received who does not intend to proceed to an uninfected locality after his probation. In other words, a camp of probation should not be used as one of refuge. The camp must be surrounded by guards to prevent egress or ingress, excepting through the established portal. At least twice or three times in the twenty-four hours all refugees should be inspected in their quarters, and any case of sickness at once 506 TEXT-BOOK OF HYGIENE. be isolated and watched until the diagnosis is certain. If the case is one of the prevailing disease, the patient must be re- moved immediately to the hospital, which should be at a safe distance, half a mile or more, from the camp. Before leaving the camp, each refugee's clothing should be fumigated, and he should be given a certificate that he has passed the required period of probation. A clear distinction must be made between camps of probation and camps of refuge. Camps of refuge are simply residence camps established to receive the population of an infected community when it has been determined to depopu- late the infected district. Depopulation of a house, a block, a district, or a whole city, if possible, the people moving into camps, is now recog- nized as a valuable means of controlling an epidemic ; and there may be either camps of probation or simply camps of refuge, or both, according to the requirements of the situation. Camps of refuge, in connection with depopulation, were sug- gested by the late Surgeon-General Wood worth, in 1878, and the measure was practically carried out at Memphis, in 1879, by the establishment of Camp Mitchell. " But the establish- ment of a camp to which persons from infected points could go, be kept under observation a sufficient length of time to demon- strate they were not infected, have their baggage disinfected, and be given 'free pratique,' is apparently a new departure in inland quarantine." Camp Perry, Fla. Such was Camp Perry, Florida, de- scribed by the surgeon in charge, W. H. H. Hutton, in the Marine-Hospital Service Report for 1889. The site was admira- bly chosen by Passed Assistant Surgeon John Guiteras, upon a bluff on the south side of St. Mary's River, the dividing line between Florida and Georgia, about forty miles north of Jack- sonville, Fla., which city was in the throes of a yellow-fever epidemic. The camp was opened August 20, 1888. It con- sisted, in its completed stage, first, of 50 wooden cottages built elsewhere and transported on cars. Their dimensions were 12 . CAMPS OF PROBATION. 507 feet by 10, and 10 feet in height, constructed of plain lumber, with cracks battened, and windows on each side with swinging o o shutters. Each held four cots, chairs, and toilet-stand, while unused clothing- was neatly arranged on the rafters above. Besides the 50 cottages there were a quartermaster and guard- house, commissary building, dining-room and kitchen, and laundry, built of rough lumber ; 2 Ducker portable barracks, each 18 by. 35 feet, provided with 12 beds each, and 350 tents, used principally by the single men, the employes and guards, and the colored refugees. So far as known, this is the first camp of the kind ever established ; at least, in the United States. The cottages were arranged in a quadrangle around a parade-ground two acres in extent, and the tents were arranged in streets and alleys in the rear of the cottages. The accommodations were sufficient for 600 people, and extra tents were on hand so that, if required, 1000 persons could have been provided for, or 3000 per month, allowing for only ten days' detention of each person. Two hundred hospital tents will accommodate 1200 people comfortably, according to Surgeon Hutton, who states that the small A-tents are unsuited for women and children, but will answer for men or boys. Wire- mattress cots should be provided. The marine-hospital officer at Savannah Ga., was the purchasing agent for the camp, and promptly forwarded all subsistence supplies on requisition by mail or telegraph. Discipline of the Camp. On arrival of a train, each pas- senger was personally examined by a physician, his health- certificate scrutinized, and he was made to await the examination of others. Hand-bags, clothing, and loose wearing-apparel were left in the baggage-car for disinfection. The refugees were then marched to the quartermaster's room for registration and assignment to quarters. On first arrival they were placed in the southern part of the camp, and in two days, there being no sickness, were moved forward several cabins, and this progres- sion was repeated until the time for discharge. 508 TEXT-BOOK OF HYGIENE. Twelve guards were employed, under the command of a captain, and were divided into squads of four each. The schedule was so arranged that each guard was on duty two hours and off duty four. A bugler announced the several calls, as follow : 5.30 A.M., .... Reveille. 6.00 A.M., .... Breakfast, employe's. 7.00 A.M., .... Breakfast, guests. 9.00 A.M., .... Surgeon's call and inspection. 12.00 M., . . . . Dinner, employe's. 1.20 P.M., .... Dinner, guests. 4.30 P.M., .... Surgeon's call and inspection. 5.30 P.M., .... Supper, guests. 6.00 P.M., .... Supper, employe's. 6.30 P.M., .... Retreat and change of guard. 9.00 P.M., .... Retiring taps. The yellow-fever hospital camp, under the special charge of Dr. Faget, was located one-half mile from the probation camp. It consisted of 2 frame buildings, 2 hospital and 12 smaller tents, arranged in a double-crescent shape, the avenue in the middle presenting an attractive appearance. Of the 12 small tents, 4 were for nurses, 3 for employes, 2 for convalescents, and 1 each for drug-store, storage- and dead- house. One of the hospital tents was used as a dining- room for employes, convalescents, and parents of the sick. The hospital was established September 3, 1888, and be- tween that date and November 24th 35 cases of yellow fever were admitted and treated, 3 died, and 32 were discharged. Twelve hundred and eleven refugees were received into Camp Perry, nearly all of whom were from the infected district of Jacksonville. Thirty-five cases of yellow fever were caught by the ten days' detention, but no case of fever was contracted at the camp, and of the 1208 refugees who passed the required detention and proceeded to different parts of the country, so far as known, not one subsequently developed or carried the disease elsewhere. CAMPS OF PROBATION. 509 The general plan of the preventive measures adopted during this epidemic will be described under Railroad Quarantine. Detention Camp, Waynesville, Ga. The epidemic of yellow fever in Brunswick, Ga., in 1893, caused the establish- ment of another camp of probation near Waynesville, Ga. Following is the report of the medical officer in command : SIB : I have the honor to present the following report of the opera- tions of the detention camp near Waynesville, Ga. The camp was officially opened for the reception of refugees from Brunswick, Ga., on the 18th of September, 1893, and closed by the order of Surgeon R. D. Murray, Marine-Hospital Service, permitting the return of all refugees to their homes in Brunswick, November 30, 1893. Four hundred and thirty-one persons availed themselves of the privileges of the camp, of whom about two hundred and twenty-five were white and the remainder black and colored. The site of the camp was selected by Surgeon W. H. H. Hutton, and was twenty-three miles west of Brunswick, immediately upon and on the south side of the Brunswick and Western Railway, and upon an eminence about twenty-five feet above the level of the surrounding coun- try, which is generally swampy, and within a mile of the margin of what is locally known as the Buffalo Swamp. As is usual in this sec- tion, the elevation was covered with a dense growth of yellow-pine, scrub-oak, and black-gum trees. The soil was a gray, sandy loam, over- lying a stratum of yellow clay, and the natural drainage of the site in all ' directions was good. On my arrival I found that, under the direction of Surgeon Hut- ton, an area of two hundred feet had been cleared of trees and under- growth, and at the four corners of this square rough but substantial buildings had been erected, which were used, respectively, as kitchen, white and colored dining-rooms, guard-room, quartermaster's store-room, executive office, telegraph office, and commissary. A depot and baggage- room were provided at the railway. Along the lines connecting these buildings, at intervals of twelve feet, were placed wall-tents, twelve by fourteen feet, with flies, and subsequently further rows of tents were pitched behind these and opening on streets fourteen feet wide. All tents were provided with substantial floors raised six inches above the ground, and the following equipment was provided: For each inmate, one spring, wire-bottomed cot, one cotton mattress, one hair pillow, two sheets, one pillow-case, and, for each tent, two tin wash-bowls, two tin cups, and two wooden chairs. Remarkable ingenuity was displayed by the 510 TEXT-BOOK OF HYGIENE. inmates in the construction of articles of furniture from packing-cases, waste lumber, etc. The tents proved of good quality in service, and quite comfortable in all weather. It is suggested, however, that any future tents be constructed with a wall two feet higher and of one foot greater pitch. A hospital establishment of two buildings was provided at a distance of one-half mile from the camp. A lofty pine-tree was fitted with a topmast, and served as a staff for the display of the national colors from sunrise to sunset each day. The following routine was observed, the calls being given by the bugle : 5.30 A.M., . . . Reveille and attendants' breakfast. 6.00 A.M., . . . Breakfast. 8.00 A.M., . . . Sick call. 12.00 M., . . . Dinner. 4.00 P.M., . . . Sick call. 5.00 P.M., . . . Supper. Sunset, . . . Retreat and call to quarters. 9.00 P.M., . . . Tattoo. 9.15 P.M., . . . Taps (extinguish lights). The meals were substantial, abundant, and as varied as possible. In all cases women and children were served at the first table, and the races were served in separate dining-rooms. The following -rules were announced, and seemed to work well in practice : 1. At reveille all inmates will rise and prepare for breakfast. 2. All quarters must be clean, floors swept, and beds made up before first sick call. 3. Meals will be served in the dining-rooms only, and at stated hours, arid no meals shall be carried from the dining-rooms to any quar- ters, except upon the written order of the medical officer, renewed from day to day. 4. At sick calls all inmates will repair to their quarters, and be there visited and inspected by the medical officer, who will prescribe or advise as he may deem best. 5. All suspicious cases of disease will be isolated at once, and until such time as the nature of the same may be determined. 6. All cases of infectious disease will be treated only in the hos- pital provided for the purpose. 7. No baggage from infected localities shall be brought into camp until disinfected by such process as may be directed, and only such wearing-apparel as may be deemed absolutely necessary will be brought into camp alter the disinfecting process. CAMPS OF PROBATION. 511 8. All wearing-apparel shall be a second time disinfected before discharge from camp. 9. Any person taken ill between two sick calls shall at once notify the nearest guard, who will, in turn, at once notify the medical officer. 10. Guards are enjoined by their vigilance to prevent the commis- sion of any nuisance near any quarters; should such nuisance be discov- ered, the inmates of the nearest quarters will be required to police the same under the supervision of the guard, who will make report of the same. 11. Inmates will confine themselves to the inner lines of the camp after retreat (sunset) call. 12. While innocent enjoyment will be encouraged, the strictest pro- priety of conduct will be demanded and enforced. The discipline of the camp was, in the main, good throughout. But two confinements for misbehavior were required during the entire dura- tion of the camp. All baggage was submitted to steam disinfection upon arrival at and departure from camp. The apparatus used was devised by Surgeou H. R. Carter, Marine-Hospital Service, and was constructed in a baggage- car, the steam being supplied by a locomotive. In addition to other duties, nearly sixteen hundred cars, boxes, and flats were disinfected for the B. and W. Railway, sulphur fumigation being used for the boxes and drenching with acid solution of bichloride of mercury (1 to 800) for flat cars. This disinfection of cars enabled the traffic into Brunswick to be carried on with a minimum of delay and hardship. Two cases of yellow fever occurred among the inmates of the camp, one resulting in recovery, one in death. Both cases occurred in the persons of sailors who had arrived in Brunswick on vessels trading there, mid both would seem to show a period of incubation of at least five days, thus justifying our detention of ten days. Recommendations. Experience having shown certain things to be desirable, I would respectfully recommend : 1st. That a disinfecting car be built and kept equipped for service in epidemics. The nine-foot chamber built by the Kensington Engine-Works of Philadelphia for this Service might be easily erected on a specially-con- structed car, and would prove more efficient in practice than extempo- rized apparatus. Another ear might be fitted with apparatus for sulphur and bichloride-of-mercury disinfection, and a tank-car similar to those used for the transportation of petroleum would complete a train that 512 TEXT-BOOK OF HYGIENE. would be always ready for emergencies in any part of the country. Steam could be supplied by a locomotive hired for the purpose. 2d. That while experience has demonstrated the usefulness of tents, those provided in the future should be higher in the pitch and the wall, and that some provision be made for heating in severe weather. It is a question in my mind whether the Sibley conical tent, made with a higher wall, would not be preferable, on this account, to the square tent. 3d. That in future epidemics of yellow fever apparatus be pro- vided for observations into temperature, temperature maximum and min- imum, barometric pressure, dew-point, direction and velocity of the wind, precipitation, and ozone. 4th. That apparatus, instruments, and reagents be provided for in- vestigation into the etiology of yellow fever in future epidemics. Yery respectfully, (Signed) H. D. GEDDINGS, P. A. Surgeon M.-H. S. To the Supervising Surgeon-General Marine-Hospital Service. RAILROAD QUARANTINE AND INSPECTION SERVICE. Railroad quarantine and inspection service may be described by a brief account of the actual measures of this nature made use of during the yellow-fever epidemic in Florida, in 1888, of which Camp Perry, just described, was an important adjunct. (For details, see annual reports Marine-Hospital Service, 1888 and 1889.) The Governor of Florida made application to the national authorities, July 16th, for aid, and it was determined to prevent further spread of the disease by disinfecting all baggage from infected localities before permitting its transportation into other States, and by enforcing, upon all persons from infected localities seeking to leave the State, a probationary detention of ten days. Accordingly, disinfection stations were established at two points, through which all persons leaving Florida by rail were obliged to pass. One of these was at Live Oak, in North- western Florida ; the other at Way Cross, Georgia, near the boundary-line of Northeastern Florida. The only other means of egress from the State was from the sea-ports ; but healthy sea-ports maintained a vigorous quarantine against people from RAILROAD QUARANTINE AND INSPECTION SERVICE. 513 the infected districts, and infected sea-ports were not visited by the steam-ship lines, because their vessels would thereby be made liable to quarantine detention at other ports. The fumigation of baggage at Live Oak and Way Cross was accomplished by means of box-cars specially prepared, and subsequently in warehouses, the agent being sulphur dioxide. Regarding persons, the inspectors, properly uniformed and wearing official shields, boarded the trains when the latter arrived at the inspection stations, and demanded of each passenger a certificate, showing where he had been during the previous ten days, which certificate was considered valid only when it bore the seal or signature of some officer of health, or recognized municipal authority. The inspectors themselves were kept informed regarding all infected or suspected localities, and a person coming from such locality was either made to return to it or given the option of going to the camp of probation, there to spend the ten days' period of probation before being allowed to enter other States. This was Camp Perry, previously described, located 38 miles south of the Way Cross Station, and 40 miles north of Jacksonville, where the epidemic prevailed chiefly. All egress from Jacksonville was, perforce, through Camp Perry and its ten days' probation. This camp was a means of protecting not only other States, but the uninfected portions of Florida itself, more particularly Southern Florida, whose health authorities refused to admit within their limits the refugees from the infected districts unless they had passed the period of probation at Camp Perry. To assist in this protection to Southern Florida, no person was allowed to board a south-bound train between Way Cross, on the north, and Orange Park, a station 20 miles south of Jacksonville. Moreover, through south-bound trains were boarded at Way Cross, and all passengers compelled to furnish evidence of coming from healthful localities. The evidence consisted of 33 514 TEXT-BOOK OF HYGIENE. certificates from local authorities, baggage-checks, or railroad- tickets showing they were purchased in the North, and in some instances letters showing by the superscription and stamps where the person had been. No train, excepting the special government train, was allowed to stop at Camp Perry. A government train also carried those who had passed the period of probation from Camp Perry to a point 3| miles distant, Folkstone, where they were transferred to a regular train running as far north as Way Cross, Ga., where another transfer had to be made to a regular north-bound train. No Florida passenger-car was allowed to go north, and more than 1000 baggage- and freight- cars were disinfected by government officers before being allowed to leave the State. Train-Inspection Service during the Brunswick Epidemic. During the Brunswick epidemic the following regulations for the inspection of trains were promulgated and enforced : Inspectors will allow none to board a train, unless with a certificate, between Way Cross and Savannah. If certificate can be examined before boarding, without detention to train, it must be done, and those which are unsatisfactory will not be allowed to board. After boarding, the certificate and the person must be carefully ex- amined and the inspector assure himself that the passenger is not recently from Jesup. or any infected locality. If the passenger is known to be a recent resident of Jesup or any infected locality, or to have been in such place during the past two (2) weeks, he will not be allowed to board, even if he has a certificate. If, after boarding, either the certificate or the examination of pas- sengers is not satisfactory, the passenger will be turned over to the city authorities at Way Cross or Savannah, or at the place where he desires to stop. If between these places, the facts to be noted and reported. A record will be kept of the names of all passengers inspected, name of signer of certificate and his rank, date of inspection, date of certificate, and place of boarding train ; and where passenger is bound and what dis- position is made of him, whether passed or turned over to local authori- ties ; also any other facts worth notice. Inspectors will aid local quarantine authorities in any way in their RAILROAD QUARANTINE AND INSPECTION SERVICE. 515 power consistent with their duties, and give them any information, obeying all local quarantine regulations. Inspectors report to Surgeon Carter, United States Marine-Hospital Service, or A. P. English, M.D. Rules Adopted by Montgomery Conference for Railroad Quarantine. The following are the rules for railroad quaran- tine adopted by the Quarantine Conference held in Montgomery, Ala., March 5 to 7, 1889 : 1. Quarantine should not be made against any place until it is officially known that yellow fever or other infectious or contagious dis- ease exists at such place. 2. Only competent physicians should be put in charge of quaran- tine stations, and only thoroughly-qualified persons should be employed as inspectors on railway-trains. 3. Quarantine stations located on railroads should be established at convenient points, on one or both sides of a town or station, as may be deemed necessary. 4. If an epidemic of yellow fever or other infectious or contagious disease exist at a town or station, trains carrying passengers or freight should be required to pass through the limits of such towns or stations at a speed of not less than ten miles per hour, without stopping at such towns or stations, but should stop at the quarantine station. 5. Passengers to or from such infected point should only be received or delivered at the quarantine station, under the supervision of the quarantine officer in Charge of the station. 6. Railway-tickets may be sold to persons leaving an infected place to any point willing to receive them. 7. All baggage from any infected point should be properly disin- fected. 8. As far as practicable, the same rules proposed for railroads should be applied to vessels of every kind, stage-coaches, or other means of travel. 9. The passage of railroad-trains through any point on the line of road, whether infected or not, should not be prohibited by any quaran- tine regulations. The conductors of passenger-trains should close the windows and ventilators and lock the doors of cars passing through any place where a train is not permitted to stop. 10. All freight to any infected place should be delivered either at the quarantine station or the nearest railway-station to such infected point where it can be properly cared for. 516 TEXT-BOOK OF HYGIENE. 11. All mail-matter from any infected place should be properly disinfected by the United States Government ; and mail-matter intended for infected points should be put off the trains at the quarantine stations. The United States Government should instruct postmasters to receive and deliver mails at such quarantine stations. 12. Railroads and express companies may receive for transporta- tion from any infected place, during the time such infection exists, any merchandise or traffic consigned to places willing to receive it. 13. State authorities should employ competent persons on passen- ger-trains as inspectors of passengers, baggage, and express matter, as additional precaution; but the fact of inspectors being on such. trains should not relieve trains carrying passengers or express ' matter or baggage from stopping at quarantine stations for such inspection as the officer in charge may determine to be necessary. 14. It is recommended that all quarantines, as far as practicable, should be uniform in their requirements and operations, which will greatly contribute to the prevention of panics, and tend to allay un- necessary excitement and fear on the part of the people. 15. The form of health certificate adopted by the Quarantine Con- vention held at Montgomery, March 5, 1889, should be prepared for health officers to issue to such persons as may be found entitled to re- ceive the same. A copy of this certificate should be printed with these rules, and conspicuously posted at railway-stations. 16. It is the desire and intention of health authorities, as far as practicable, to throw every safeguard around the public health of all localities. Municipal, county, and State authorities are expected to co-operate in every possible way with health officers located in towns, villages, and cities, and in charge of quarantine stations, to enable them to prevent the introduction or spread of yellow fever or other infectious or contagious diseases. It was also resolved by this conference that the best form of disinfectant for personal baggage is moist heat. The methods of railroad quarantine may also be studied in a review of the action taken to prevent the introduction of small-pox into the United States from Canada, where it prevailed extensively in the fall and wiflter of 1885, and January and February, 1886. The following regulations were issued by the Surgeon- General of the Marine-Hospital Service, October 10, 1885 : RAILROAD QUARANTINE AND INSPECTION SERVICE. 517 The act approved April 29, 1878, entitled "An act to prevent the introduction of contagious or infectious diseases into the United States," provides that no vessel or vehicle coming from any foreign port or country where any contagious or infectious disease exists, or any vessel or vehicle conveying persons, merchandise, or animals affected with any contagious disease, shall enter any port of the United States, or pass the boundary-line between the United States and any foreign country, except in such manner as may be prescribed under said act.^ Attention is now directed to the prevalence of the contagious and infectious disease of small-pox in Montreal and other places in the Do- minion of Canada, and the law referred to is held to apply alike to trains of cars ami other vehicles crossing the border, and to vessels entering ports on the northern frontier. Because, therefore, of the danger which attaches to the transporta- tion of persons and baggage, and articles of merchandise, or animals, from the infected districts, the following regulations are framed, under the direction of the Secretary of the Treasury, and subject to the ap- proval of the President, for the protection of the health of the people of the United States against the danger referred to : 1. Until further orders all vessels arriving from ports in Canada, and trains of cars and other vehicles crossing the border-line, must be examined by a medical inspector of the Marine-Hospital Service before they will be allowed to enter the United States, unless provision shall have been made by State or municipal quarantine laws and regulations for such examination. 2. All persons arriving from Canada, by rail or otherwise, must be examined by such medical inspector before they will be allowed to enter the United States, unless provision has been made for such examination. 3. All persons coming from infected districts, not giving satisfac- tory evidence of protection against small-pox, will be prohibited from proceeding into the United States until after such period as the medical inspector, the local quarantine, or other sanitary officer duly authorized, may direct. 4. The inspectors will vaccinate all unprotected persons, who desire or are willing to submit to vaccination, free of charge. Any such person refusing to be vaccinated shall be prevented from entering the United States. 5. All baggage, clothing, and other effects, and articles of mer- chandise, coming from infected districts, and liable to carry infection, or suspected of being infected, will be subjected to thorough disinfection. 6. All persons showing evidence of having had small-pox or vario- loid, or who exhibit a well-defined mark of recent vaccination, may be 518 TEXT-BOOK OF HYGIENE. considered protected ; but the wearing-apparel and baggage of such pro- tected persons who may come from infected districts, or have been exposed to infection, will be subjected to thorough disinfection as pro- vided. 7. Customs officers and United States medical inspectors will con- sult and act in conjunction with authorized State and local health author- ities so far as may be practicable, and unnecessary detention of trains or other vehicles, perfpns, animals, baggage, or merchandise, will be avoided so far as may be consistent with the prevention of the introduction of diseases dangerous to the public health into the United States. 8. Inspectors will make full weekly reports of services performed under this regulation. 9. As provided in Section 5 of said act, all quarantine officers or agents acting under any State or municipal system, upon the application of the respective State or municipal authorities, are empowered to enforce the provisions of these regulations, and are hereby authorized to prevent the entrance into the United States of any' vessel or vehicle, person, merchandise, or animals prohibited under the act aforesaid. 10. In the enforcement of these regulations there shall be no inter- ference with any quarantine laws or regulations existing under or to be provided for by any State or municipal authority. The following are the special instructions for the guidance of sanitary inspectors, issued by Surgeon H. W. Austin, in charge of the inspection service on the Canadian frontier from Buffalo, N. Y., to the Atlantic coast during the epidemic above referred to (see Marine-Hospital Report, 1886): REGULATIONS FOR SANITARY INSPECTORS. The following instructions will be observed by the sanitary inspec- tor on the following-mentioned railroads crossing the United States boundary-line, viz., the Grand Trunk Railway, at Rouse's Point, N. Y., and Island Pond, Vt. ; the Passumpsic Railroad, at Newport, Yt. ; the Central Vermont Railroad, at Highgate Springs or Saint Albans; the Canada Atlantic, at Rouse's Point, X. Y., and the Southeastern Rail- way, at Richford, Yt. : All persons bound for the United States coming from Montreal, or other places in Canada where small-pox prevails, must produce satisfac- tory evidence to the inspector that they are protected by a recent vaccination, or submit to this operation before they are allowed to cross the boundary -line. RAILROAD QUARANTINE AND INSPECTION SERVICE. 519 Inspectors will vaccinate all unprotected persons free of charge. Persons coming from Montreal, or suburban villages, will be care- fully questioned as to their residence, whether small-pox has occurred in their families, or whether they have been in contact with the disease. Inquiries should also be made relative to their baggage, whether it consists of bedding, household goods, etc., likely to be infected; and if any person or article of baggage is considered by the inspector infected or likely to introduce the disease into the country, he or it should not be permitted to cross the line into the United States. You may consider persons protected who may show evidence of having had the small-pox or varioloid, or who exhibit a well-defined mark of vaccination. Accept as evidence of protection a certificate from any physician in good standing that the person presenting the same has been successfully vaccinated. Should you doubt the validity or authenticity of the certificate, you may refuse any such person presenting the same the privilege of crossing the border unless he submits to vaccination. Baggage known to have come from an} 7 infected district, and believed to be infected, will be thoroughly fumigated with sulphur at Rouse's Point, Saint Albans, Richford, Newport, and Island Pond. Weekly reports should be made to Surgeon H. W. Austin, United States Marine-Hospital Service, Burlington, Vt., of the number of trains inspected, number of persons examined, number of persons vaccinated, number of pieces of baggage fumigated, and any other information relative to services performed by the inspector. It will be observed that all the railroads, five in number, over which passengers or freight might be brought direct from Canada into the New England States, were guarded. Besides the line commanded by Surgeon Austin (Atlantic coast to Buffalo), another line was under the direction of Passed Assistant Surgeon Wheeler, at points east of Buffalo, and still another on the Michigan frontier, under command of Surgeon W. H. Long. These lines were established at the request and with the co-operation of the authorities of the respective States. Thirty-six inspectors were employed at 37 stations, who exam- ined 49,631 persons on railroad-trains, vaccinated 16,547, and detained or sent back 603. The contents of more than 7000 pieces of baggage were disinfected. The measures taken were successful. 520 TEXT-BOOK OF HYGIENE. In 1893, at a time when there was imminent danger that cholera might be introduced into the sea-board cities of the United States and carried by immigrants to the far West and the interior cities and towns, a most carefully formulated plan of railroad medical inspection of immigrants was drawn up ; and while it was, fortunately, never necessary to carry out the pro- visions made at the time, the following regulations will well show the scope and general design of the protective and restrictive measures contemplated : RAILROAD MEDICAL INSPECTION OF IMMIGRANTS. TREASURY DEPARTMENT, Office of the Supervising Surgeon-General United States Marine- Hospital Service, WASHINGTON, August 23, 1893. Instructions for the Guidance of Medical Officers of the Marine-Hospital Service, Sanitary Inspectors, and others concerned. 1. One or more medical inspectors shall accompany immigrants from the point of departure of each immigrant train, and shall im- mediately commence making a careful inspection of every passenger man, woman, and child upon the train. This inspection shall consist in identifying each passenger with the health card or cards he or she may hold, and satisfying himself as to the health of each person at the time of said inspection. He shall pass through the train once every hour or oftener, if he has reason to believe any person is suffering with diarrhoea or other symptoms of cholera. 2. The railroad companies will be expected to furnish earth-closets, which should be used, and the regular closets of the car are to be locked. These earth-closets shall be destroyed, before the train reaches its des- tination, at such points as the railroad officials shall designate. It shall be the duty of the inspector to see that the earth-closets are kept clean and frequently disinfected, and the cars properly ventilated and free from all offensive odors and dirt. 3. He shall, upon the least suspicion of cholera among the immi- grants, have the suspected person or persons immediate^ removed to the hospital car at the rear of the train, disinfect all ejecta, and take every precaution possible to prevent the spread of the disease among the passengers by thoroughly disinfecting that portion of the car occupied by the suspects, the simplest means for this purpose being a solution of bichloride of mercury in the proportion of 1 to 800. INTERSTATE QUARANTINE. 521 4. The inspectors will at once notify the conductor of the train upon the first appearance of a suspicious case, in order that the hospital cur may be switched off at the first designated switch, and the health officer of the county in which said switch is located be immediately notified to take charge of this car. 5. It is expected that the railroads will furnish a car for hospital purposes, in which the seats can be readily converted into beds suitable for the care of the sick. The necessary bedding will be furnished by the United States Marine-Hospital Service. 6. Disinfectants, consisting of packages of bichloride of mercury and an alkali, will be furnished the medical inspector in proper quantities for adding to a two-gallon wooden bucket of water; also a quantity of carbolic acid in solution and other approved disinfectants. Each hospital car shall be equipped with a dozen two-gallon wooden buckets for holding disinfecting ffuids, half a dozen mops, one or more hand force-pumps with rose sprinklers, one or more commodes and bed-pans, half a dozen eight-ounce hard-rubber syringes, half a dozen tumblers, one dozen rubber sheets, and one dozen feeding-cups for administering medicine. There shall also be furnished an oil-stove for heating water, and several tin boilers and tin cups. 7. Medical supplies, etc., consisting of tannic acid, hydrarg. chlori- dum mite, tincture of opium, mustard or mustard papers, chloroform or ether sulph., whisky, brandy, and one or more hypodermatic syringes ; also supply of Squibb's Diarrhoea Mixture for checking looseness of the bowels or premonitory diarrhoea. WALTER WYMAN, Supervising Surgeon-General. INTERSTATE QUARANTINE. The general principles governing interstate quarantine are the same as those pertaining to the maritime and foreign quar- antines, with the exception that, instead of dealing with ships as the media of transportation, we must deal with trains on rail- roads, lines of stage-coaches, and steam-boats plying on the inland waters of the United States. The principles are almost sufficiently elahorated in the previous sections on train inspection in the case of yellow-fever epidemics, and the precautions which were under consideration for the prevention of the spread of cholera by means of emigrant trains. An important matter is the one of notification. It will be 522 TEXT-BOOK OF HYGIENE. seen, by a study of the regulations for interstate quarantine which follow, that State and municipal health officers are requested to notify the Supervising Surgeon-General of the ap- pearance of any of the quarantinable diseases in their States or localities, thus enabling appropriate measures to be taken to prevent their spread without the loss of valuable time, for time in the management of epidemics is of the utmost importance. Many an epidemic which has assumed vast proportions would, if recognized in time, have been capable of easy management and of being confined to the seat of its first outbreak. It is always comparatively easy to confront an open enemy ; it is the insidious spread of disease, either unrecognized or concealed for reasons of business policy, that causes delay in the inception of preventive measures, and is most to be dreaded from a sanitary stand-point. The following are the regulations prepared in the Marine- Hospital Bureau to prevent the introduction of contagious dis- eases into one State or Territory or the District of Columbia from another State or Territory or District of Columbia. It is ex- pected that additional regulations will be promulgated from time to time as circumstances demand : INTERSTATE QUARANTINE. ARTICLE I. QUARANTINE DISEASES. 1. For the purpose of these regulations the quarantinable diseases are cholera (cholerine), yellow fever, small-pox, typhus fever, leprosy, and plague. ARTICLE II. NOTIFICATION. 1. State and municipal health officers should immediately notify the Supervising Surgeon-General of the United States Marine-Hospital Service, by telegraph or by letter, of the existence of any of the above- mentioned quarantinable diseases in their respective States or localities. ARTICLE III. GENERAL REGULATIONS. 1. Persons suffering from a quarantinable disease shall be isolated until no longer capable of transmitting the disease to others. Persons exposed to the infection of a qunrantinable disease shall be isolated, INTERSTATE QUARANTINE. 523 under observation, for such a period of time as may be necessary to demonstrate their freedom from the disease. All articles pertaining to such persons, liable to convey infection, shall be disinfected us hereinafter provided. 2. The apartments occupied by persons suffering from quarantin- able disease, and adjoining apartnftnts, when deemed infected, together with articles therein, shall be disinfected upon the .termination of the disease. 3. Communication shall not be held with the above-named persons and apartments, except under tlie direction of a duly-qualified officer. 4. All cases of quarantinable disease, and all cases suspected of belonging to this class, shall be at once reported by the physician in attendance to the proper authorities. 5. No common carrier shall accept for transportation any person suffering with a quarantinable disease, nor any infected article of clothing, bedding, or personal property. Bodies of persons who have died from any of the said diseases shall not be transported save in hermetically-sealed coffins, and by the order of the State or local health officer. 6. In the event of the prevalence of small-pox, all persons exposed to the infection, who are not protected by vaccination or a previous attack of the disease, shall be at once vaccinated or isolated for a period of fourteen days. 7. During the prevalence of cholera, all the dejecta of cholera patients shall be at once disinfected, as hereinafter provided, t prevent possible contamination of the food- and water- supply. ARTICLE IV. YELLOW FEVER. In addition to the foregoing regulations contained in Article I, the following special provisions are made with regard to the prevention of the introduction and spread of yellow fever : 1. Localities infected with yellow fever, and localities contiguous thereto, should be depopulated as rapidly and as completely as possible, so far as the same can be safely done; persons from non-infected locali- ties, and who have not been exposed to infection, being allowed to leave without detention. Those who have been exposed, or who came from infected localities, shall be required to undergo a period of detention and observation of ten days, from the date of last exposure, in a camp of probation or other designated place. Clothing and other articles capable of conveying infection shall not be transported to non-infected localities without disinfection. 2. Persons who have been exposed may be permitted to proceed 524 TEXT-BOOK OF HYGIENE. without detention to places willing to receive them, and incapable of be- coming infected, when arrangements have been perfected to the satisfac- tion of the proper health officer to insure their detention in said places for a period of ten days. 3. The suspects who are isolated under the provisions of paragraph 1, Article III, shall be kept free fronf all possibility of infection. 4. So far as possible the sick should be removed to a central loca- tion for treatment. 5. Buildings in which yellow fever has occurred, and localities be- lieved to be infected with said disease, must be disinfected as thoroughly as possible. 6. As soon as the disease becomes epidemic, the railroad-trains carrying persons allowed to depart from the city or place infected with yellow fever shall be under medical supervision. 7. Common carriers from the infected districts, or believed to be carrying persons and effects capable of conveying infection, shall be sub- ject to sanitary inspection, and such persons and effects shall not be allowed to proceed, except as provided for by paragraph 2. 8. At the close of un epidemic the houses where sickness has occurred, and the contents of the same, and houses and contents that are presumably infected, shall be disinfected as hereinafter prescribed. ARTICLE V. DISINFECTION. For Cholera. 1. The dejecta and vomited matters of cholera patients shall be received into vessels containing an acid solution of bichloride of mer- cury (bichloride of mercury, 1 part ; hydrochloric acid, 2 parts ; water, 1000 parts) or other efficient germicidal agent. 2. All bedding, clothing, and wearing-apparel soiled by the dis- charges of cholera patients shall be disinfected by one or more of the following methods : (a) Ity complete immersion for thirty minutes in one of the above- named disinfecting solutions. (6) By boiling for fifteen minutes, all articles to be completely sub- merged. (c) By exposure to steam at a temperature of 100 to 102 C. for thirty minutes after such temperature is reached. 3. Any woodwork or furniture contaminated by cholera discharges shall be disinfected by thorough washing with a germicidal solution as provided in paragraph 1, Article Y. INTERSTATE QUARANTINE. 625 For Yellow Fever. 4. Apartments infected by occupancy of patients sick with yellow fever shall be disinfected by one or more of the following methods : (a) By thorough washing with one of the germicidal solutions mentioned. If apprehension is felt as to the poisonous effects of the .mercury, the surfaces may, after two hours, be washed with clear water. (b) Thorough washing with a 5-per-cent. solution of pure carbolic acid. (c) By sulphur dioxide, twenty-four to forty-eight hours' exposure, the apartments to be rendered as air-tight as possible. iv Bedding, wearing-apparel, carpets, hangings, and draperies infected by yellow fever shall be disinfected by one of the following methods : (a) By exposure to steam at a temperature of 100 to 102 C. for thirty minutes after such temperature is reached. (6) By boiling for fifteen minutes, all articles to be completely submerged. (c) By thorough saturation in a solution of bichloride of mercury, 1 to 1000, the articles being allowed to dry before washing. Articles injured by steam (rubber, leather, containers, etc.), to the disinfection of which steam is inapplicable, shall be disinfected by thor- oughly wetting all surfaces with (a) a solution of bichloride of mercury 1 to 800, or (6) a 5-per-cent. solution of carbolic acid, the articles being allowed to dry in the open air prior to being washed with water, or (c) \)y exposure to sulphur fumigation in an apartment air-tight, or as nearly so as possible. For Small-pox. 6. Apartments infected by small-pox shall be disinfected by one or both of the following methods : (a) Exposure to sulphur dioxide for twenty-four to forty-eight hours. (6) Washing with a solution of bichloride of mercury 1 to 1000, or a 5-per-cent. solution of pure carbolic acid. 7. Clothing, bedding, and articles of furniture exposed to the infec- tion of small-pox shall be disinfected by one or more of the following methods : (a) Exposure to sulphur dioxide for twenty-four to forty-eight hours. (6) Immersion in a solution of bichloride of mercury 1 to 1000, or a 5-per-cent. solution of pure carbolic acid. (c) Exposure to steam at a temperature of 100 to 102 C. for thirty minutes after such temperature is reached. 526 TEXT-BOOK OF HYGIENE. (d) Boiling for fifteen minutes, the -articles to be completely sub- merged. For Typhus Fever. 8. Apartments infected by typhus fever shall be disinfected by one or both of the following methods : (a) Exposure to sulphur dioxide for twenty-four to forty-eight hours. (6) Washing with a solution of bichloride of mercury 1 to 1000, or a 5-per-cent. solution of pure carbolic acid. 9. Clothing, bedding, and articles of furniture exposed to thf infec- tion of typhus fever, shall be disinfected by one or more of the following methods : (a) Exposure to sulphur . dioxide for twenty-four to forty-eight hours. (6) Immersion in a solution of bichloride of mercury 1 to 1000, or a 5-per-cent. solution of pure carbolic acid. (c) Exposure to steam at a temperature of 100 to 102 C. for thirty minutes after such temperature is reached. (d) Boiling for fifteen minutes, the articles to be completely sub- merged. MUNICIPAL QUARANTINE. It is now generally conceded that a small number of cases of certain ones of the quarantinable diseases may exist in a city of considerable size, without giving rise to serious apprehension, if intelligent and vigorous measures for the prevention of its spread are taken, and if scientific measures for the isolation of patients, the surveillance of those exposed to infection, and the disinfection of apartments and articles infected are carried out. It is regarded as very important that the sick should be removed to centrally-located hospital establishments for treatment, thus increasing ease of management and administration, and dimin- ishing the number of foci of infection. The surveillance of those exposed to infection should, in general, be for a period of time equal to the usual period of incubation of the disease to which they have been exposed. In the case of small-pox it may be unnecessary at times to detain the suspects the full period of incubation, provided they are vaccinated and their clothing and MUNICIPAL QUARANTINE. 527 personal effects are rendered safe by efficient disinfection. They should, however, be kept under observation. For the suppression of small-pox in cities in which it has made its appearance, and in which it threatens to become epi- demic, the following suggestions, made by the health authorities of the Northwest, will undoubtedly prove of value : 1. The city should be divided into districts containing not more than 10,000 people. 2. Each district should be placed under the supervision of a compe- tent medical inspector with necessary assistants (a) to make a house- to-house inspection ; (6) to successfully vaccinate, within the shortest possible time, all persons who have not been vaccinated during the out- break, the first vaccination to be completed within seven days ; (c) to properly disinfect all houses and their contents where small-pox occurs. 3. Necessary means and appliances for efficient disinfection of ma- terials, premises, etc., should be provided as the exigencies of each district may require. 4. Each case of small-pox should be immediately removed to a suitably constructed and properly equipped and officered isolation hospital. 5. Except in extreme cold weather, hospital tents, as prescribed in the United States Army Regulations, floored and warmed, are preferable to the average hospital or private dwelling, and increase the chances of recovery of the patients. Cases of small-pox necessarily retained in their own homes should, with their attendants, be rigidly isolated during the period of danger, and physicians visiting such patients professionally should be subject to such regulations as may be prescribed by the local health officer. 6. Persons exposed to small-pox contagion should be immediately vaccinated and kept under observation for not less than fourteen days from time of last exposure. 7. It is the sense of this Conference that unless such measures are enforced, it will be necessary for neighboring cities and States to exclude all persons from such city who are not protected against small-pox by recent vaccination, and to require proper disinfection of all clothing, bag- gage, and merchandise capable of conveying small-pox infection. The subject of municipal quarantine naturally suggests a subdivision of the subject, viz., domiciliary quarantine, or the ex- ercise of restrictive measures against a particular house or part 528 TEXT-BOOK OF HYGIENE. of a house on account of the occurrence of a quarantinable dis- ease within its limits. These can best be accomplished by the stationing of guards to see that none enter or leave the infected premises except those necessary to care for the sick, viz., phy- sicians and nurses. All intercourse between the outside world and the house under quarantine should be carried on by messengers who should not be allowed to enter the premises, but who should report to the guards. It would be most desirable that the physicians and nurses, on leaving the premises, should practice personal disinfection of hands, at least; though, of course, it would be better if, in ad- dition to this, a change into sterile clothing were made prior to coming into contact with the public. It goes without saying that the room of the patient should be absolutely closed to the ingress of all save the physicians and nurses, and it is a practice of considerable value to provide all room-openings with curtains or hangings, which are to be kept constantly wet with a germicidal solution. The dejecta, vomited matter, and sputum should be promptly disinfected according to circumstances. When the disease has terminated, the house or apartments are to be thoroughly disinfected by one of the methods prescribed in the regulations, the method chosen being adapted to the disease which has prevailed. For the purposes of municipal disinfection the Marine-Hospital Service has had constructed portable apparatus for the use of steam and sulphur, which are, in effect, the same apparatus as have been previously described in this article, modified to meet their special require- ments. An important factor in the measures taken to suppress any epidemic disease is a house-to-house inspection, to ascertain the actual number of cases existing. Whether this inspection should include the whole city, or only the infected district, is a matter for the exercise of judgment ; but, when required, the in- spections should be made at intervals corresponding with the usual periods of incubation of the disease under observation. DIPHTHERIA AND SCARLET FEVER. 529 A very important field for the exercise of municipal and domiciliary quarantine is furnished by those contagious and in- fectious diseases which, while causing large mortality, seldom prevail in epidemic form, viz., measles, scarlet fever, diphtheria, and tuberculosis. MEASLES. Measles may be dismissed with a few words. The course of the disease, uncomplicated, is usually so benign, especially in children, that all that is necessary is isolation. At the conclusion of the case or cases the apartment should be well aired, and it may be advisable to subject the room and the contents, bedding, and clothing to fumigation by sulphur. DIPHTHERIA AND SCARLET FEVER. With diphtheria and scarlet fever the conditions are far different. The diseases are virulent: the infection is subtle, and their spread very much to be dreaded. Vigorous effort alone can prevent their spread. Dwellings where the disease prevails must be placarded, special hospitals should be provided, and disinfection should be intelligently performed by competent municipal authority. The regulations of the Board of Health of the District of Columbia are given here, as embodying the most recent practice in the management of these diseases : REGULATIONS TO PREVENT THE SPREAD OF DIPHTHERIA AND SCARLET FEVER. The following regulations, provided for in the Act of Congress approved December 20, 1890, are promulgated for the information of all concerned : The act referred to provides, in Section 2, " That it shall be the duty of the health officer, in conjunction with the attending physician, to cause the premises to be properly disinfected, and to issue the neces- sary instructions for the isolation of the patient "; in Section 3, " That it shall be the duty of physicians, while in attendance upon cases of scarlet fever and diphtheria, to exercise such reasonable precautions to prevent the spread of the said diseases as may be prescribed by the 34 530 TEXT-BOOK OF HYGIENE. health officer of the District of Columbia in regulations " ; in Section 6, " That the word ' regulations,' as herein used, shall be held to mean, also, rules, orders, and amendments." The term " scarlet fever," as applied in the act, shall be held to in- clude scarlatina, scarlet rash, and canker rash, and each and every case must be reported upon the forms provided. Warning-signs shall remain displayed on houses, in cases of scarlet fever, for a period of not less than four weeks, and in cases of diphtheria for not less than three weeks from date of report to the health officer, and for a longer period, unless report of recovery by the physician in attendance has been made. In cases of death, the warning-sign shall remain displayed upon premises for a period of not less than seven days, and longer, unless the health officer is satisfied that all proper means have been employed for prevention of the spread of the contagion. It shall be the duty of the householder, in every case where a warning-sign has been displayed from the premises which he or she occu- pies, to report prompt!}- the removal of such sign at any time within the periods given. It shall be the like duty of the physician in attendance to make such report to the health officer of the removal of warning-signs, unless assured that the report has been made by some one from the premises where the disease is prevailing or has prevailed. It shall be the duty of the physician in attendance to report, in every instance, on the forms provided, whether or not children in the family or other children in the same building attend school, and at what school-building or buildings. Children shall not be permitted to return to school from infected premises, except upon presentation of the proper certificate from the health officer. All persons suffering from either diphtheria or scarlet fever are to be isolated in rooms as far removed as possible from those occupied by other persons in the building, and upon the top floor, where it is prac- ticable. No person, other than the physician in attendance, the examin- ing official, and the nurse or nurses, shall be admitted to such room during the prevalence of the disease. Every room occupied by a patient suffering from either diphtheria or scarlet fever shall be cleared of all needless clothing, carpets, drapery, and other materials likely to harbor the poisons of the disease. Soiled bed- and body- linen shall be immediately placed in vessels of water containing a solution of bichloride of mercury, chloride of zinc, or other suitable disinfectant. DIPHTHERIA AND SCARLET FEVER. 531 Excremental discharges from the patient shall be received in vessels of water containing such a solution, and all vessels used shall be kept scrupulously clean and thoroughly disinfected. Discharges from the throat, nose, and mouth shall be received upon pieces of cloth, which must be immediately burned. All persons recovering from either diphtheria or scarlet fever shall be considered dangerous, and shall not be permitted to associate with others, or to attend school, church, or any public assembly, until a cer- tificate has been furnished by the health officer to the effect that they may go abroad without danger of disseminating the contagion. It shall be the duty of the person in charge of the premises where a case of diphtheria or scarlet fever exists, to exercise all reasonable care in the prevention of the commingling of persons who come into contact with the patient, or any other persons, whereby the contagion might be disseminated. The body of a person who has died from either diphtheria or scarlet fever shall be immediately disinfected and placed in a coffin, which shall be tightly closed, and shall not be taken to any church or place of public assembly, and shall be buried within forty -eight hours, unless otherwise ordered by the health officer. No public funeral shall be held in a dwelling in which there is a case of either diphtheria or scarlet fever, nor in which a death from either of said diseases has recently occurred. Immediately upon the recovery of a person who has been suffering from either diphtheria or scarlet fever, or upon the death of a person who has been so suffering, the room or rooms occupied shall be thoroughly disinfected by exposure for several hours to the fumes of chlorine gas, or of burning sulphur, and shall thereafter be thoroughly cleaned and exposed to currents of fresh air. All clothing, bedding, carpets, and other textiles which have been exposed to the contagion of the disease shall be either burned, exposed to superheated steam, or thoroughly boiled. No person shall interfere with or obstruct the entrance, inspection, and examination of any building or house, by the inspectors or officers of this department, when there has been reported the case of a person sick with either scarlet fever or diphtheria therein. Diagnosis of Diphtheria. For the more prompt and cer- tain diagnosis of diphtheria, small wooden boxes are distributed to the various pharmacies in Washington, each box holding two glass tubes, one tube containing a small cotton swab, the other 532 TEXT-BOOK OF HYGIENE. containing solidified blood-serum as a culture medium. Each tube is sterilized and plugged with cotton. The following notice is inclosed in each box : DIRECTIONS FOR MAKING CULTURES IN SUSPECTED CASES OF DIPHTHERIA. The patient should be placed in the best light attainable, and, if a child, property held. In cases where it is possible to get a good view of the throat, depress the tongue and rub the cotton swab gently, but freely, against any visible pseudomembrane or exudate. 1 In other cases, including those in which the exudate is confined to the larynx, open the mouth and pass the swab back till it reaches the pharynx, and then rub it freely against the mucous membrane. Without laying the swab down, withdraw the cotton plug from the culture-tube, insert the swab, and rub that portion of it which has touched the exudate gently back and forth along the surface of the blood-serum. Then replace the swab in its own tube, plug both tubes, and send the whole outfit at once to the laboratory. A report will be forwarded the following morning, by mail, or can be obtained by telephone. TUBERCULOSIS. With the discovery by Koch of the cause of tuberculosis, and the numerous researches made by him and other observers into the nature of the tuberculous poison, has grown the con- viction, of late years, that tuberculosis, being communicable, is to a large extent preventable. The bacillus tuberculosis is the etiological factor of most importance in the spread of tuber- culosis ; it has been proved that it is contained in large numbers in the sputum of tuberculous patients, and that, unlike most micro-organisms, its vitality is not destroyed by drying. There- fore, with the careful disinfection or destruction of the expecto- ration of tuberculous patients, one most important factor in the dissemination of tuberculosis will be removed. In almost all large hospitals, at the present day, the practice obtains of either isolating the tuberculous patients or of segregating them in special wards or apartments. With a view of preventing the spread of tuberculosis, the Board of Health of New York City 1 This should be done before any germicide lias been applied, and, if this has been done, allow at least an hour to intervene before making the inoculation. TUBERCULOSIS. 533 has issued in English, German, Hebrew, and Italian the follow- ing circular for popular instruction : Consumption is a disease which can be taken from others, and is not simply caused by colds. A cold may make it easier to take the dis- . ease. It is usually caused by germs which enter the body with the air breathed. The matter which consumptives cough or spit up contains these germs in great numbers ; frequently millions are discharged in a single day. This matter, spit upon the floor, wall, or elsewhere, is apt to dry, become pulverized, and float in the air as dust. This dust con- tains the germs, and thus they enter the body with the air breathed. The breath of a consumptive does not contain the germs, and will not produce the disease. A well person catches the disease from a con- sumptive only by in some way taking the matter coughed up by the consumptive. Consumption can often be cured if its nature is recognized early and proper means are taken for its treatment. In a majority of cases it is not a fatal disease. It is not dangerous for other persons to live with a consumptive if the matter coughed up by the consun\ptive is at once destroyed. This matter should not be spit upon the floor, carpet, stove, wall, or street, or anywhere except into a cup kept for that purpose. The cup should con- tain water, so that the matter may not dry, and should be emptied into the closet at least twice a day, and carefully washed with hot water. Great care should be taken by a consumptive that his hands, face, and clothing do not become soiled with the matter coughed up. If they do become soiled, they should be at once washed with hot water and soap. When consumptives are away from home, the matter coughed up may be received on cloths, which should be at once burned on returning home. If handkerchiefs are used (worthless cloths which can be burned are far better), they should be boiled in water by themselves before being washed. It is better for a consumptive to sleep alone, and his bed-clothing and personal clothing should be boiled and washed separately from the clothing belonging to other people. Whenever a person is thought to be suffering from consumption, the name and address should be sent at once to the health department, on a postal card, with a statement of this fact. A medical inspector from the health department will then call and examine the person to see if he has consumption, providing he has no physician, and, if necessary, will give proper direction to prevent others from catching the disease. Frequently a person suffering from consumption may not only 534 TEXT-BOOK OF HYGIENE. do bis usual work without giving the disease to others, but may also get well, if the matter coughed up is properly destroyed. Rooms that have been occupied by consumptives should be thor- oughly cleaned, scrubbed, whitewashed, painted or papered before they are again occupied. Carpets, rugs, bedding, etc., from rooms which have been occupied by consumptives, should be disinfected. The health department should be notified, when they will be sent for, disinfected, and returned to the owner free of charge ; or, if he so desire, they will be destroyed. QUARANTINE LAWS OF THE UNITED STATES. AN ACT granting additional quarantine powers and imposing additional duties upon the Marine-Hospital Service. [Approved February 15, 1893.] Be it enacted by the Senate and House of Representatives of the United States of America in Congress assembled, That it shall be unlaw- ful for any merchant ship or other vessel from any foreign port or place of [to] enter any port of the United States except in accordance with the provisions of this act and with such rules and regulations of State and municipal health authorities, as may be made in pursuance of, or consistent with, this act ; and any such vessel which shall enter, or attempt to enter, a port of the United States in violation thereof shall forfeit to the United States a sura, to be awarded in the discretion of the court, not exceeding five thousand dollars, which shall be a lien upon said vessel, to be recovered by proceedings in the proper district court of the United States. In all such proceedings the United States Dis- trict Attorney for such district shall appear on behalf of the United States ; and all such proceedings shall be conducted in accordance with the rules and laws governing cases of seizure of vessels for violation of the revenue laws of the United States. SEC. 2. That any vessel at any foreign port clearing for any port or place in the United States shall be required to obtain from the consul, vice-consul, or other consular officer of the United States at the port of departure, or from the medical officer where such officer has been de- tailed by the President for that purpose, a bill of health, in duplicate, in the form prescribed by the Secretary of the Treasun-, setting forth the sanitary history and condition of said vessel, and that it has in all re- spects complied with the rules and regulations in such cases prescribed for securing the best sanitary condition of the said vessel, its cargo, passengers, and crew ; and said consular or medical officer is required, before granting such duplicate bill of health, to be satisfied that the matters and things therein stated are true ; and for his services in that QUARANTINE LAWS OF THE UNITED STATES. 535 behalf he shall be entitled to demand and receive such fees as shall by lawful regulation be allowed, to be accounted for as is required in other cases. The President, in his discretion, is authorized to detail any medical officer of the government to serve in the office of the consul at any foreign port for the purpose of furnishing information and making the inspection and giving the bills of health hereinbefore mentioned. Any vessel clearing and sailing from any such port without such bill of health, and entering any port of the United States, shall forfeit to the United States not more than five thousand dollars, the amount to be determined by the court, which shall be a lien on the same, to be recov- ered by proceedings in the proper district court of the United States. In all such proceedings the United States District Attorney for such dis- trict shall appear on behalf of the United States ; and all such proceed- ings shall be conducted in accordance with the rules and laws governing cases of seizure of vessels for violation of the revenue laws of the United States. SEC. 3. That the Supervising Surgeon-General of the Marine-Hos- pital Service shall, immediately after this act takes effect, examine the quarantine regulations of all State and municipal boards of health, and shall, under the direction of the Secretary of the Treasury, co-operate with and aid State and municipal boards of health in the execution and enforcement of the rules and regulations of such boards and in the ex- ecution and enforcement of the rules and regulations made by the Sec- retary of the Treasury to prevent the introduction of contagious or infectious diseases into the United States from foreign countries, and into one State or Territory or the District of Columbia from another State or Territory or the District of Columbia ; and all rules and reg- ulations made by the Secretary of the Treasury shall operate uniformly and in no manner discriminate against any port or place ; and at such ports and places within the United States as have no quarantine reg- ulations under State or municipal authority, where such regulations are, in the opinion of the Secretary of the Treasury, necessary to prevent the introduction of contagious or infectious diseases into the United States from foreign countries, pr into one State or Territory or the Dis- trict of Columbia from another State or Territory or the District of Columbia, and at such ports and places within the United States where quarantine regulations exist under the authority of the State or munici- pality which, in the opinion of the Secretary of the Treasury, are not sufficient to prevent the introduction of such diseases into the United States, or into one State or Territory or the District of Columbia from another State or Territory or the District of Columbia, the Secretary of 536 TEXT-BOOK OF HYGIENE. the Treasury shall, if in his judgment it is necessary and proper, make such additional rules and regulations as are necessary to prevent the in- troduction of such diseases into the United States from foreign countries, or into one State or Territory or the District of Columbia from another State or Territory or the District of Columbia; and when said rules and regulations have been made they shall be promulgated by the Secretary of the Treasury and enforced by the sanitary authorities of the States and municipalities, where the State or municipal health authorities will un- dertake to execute and enforce them ; but if the State or municipal au- thorities shall fail or refuse to enforce said rules and regulations, the President shall execute and enforce the same and adopt such measures as in his judgment shall be necessary to prevent the introduction or spread of such diseases, and may detail or appoint officers for that pur- pose. The Secretary of the Treasury shall make such rules and regula- tions as are necessar}^ to be observed by vessels at the port of departure and on the voyage, where such vessels sail from any foreign port or place to any port or place in the United States, to secure the best sanitary condition of such vessel, her cargo, passengers, and crew ; which shall be published and communicated to and enforced by the consular officers of the United States. None of the penalties herein imposed shall attach to any vessel or owner or officer thereof until a copy of this act, with the rules and regulations made in pursuance thereof, has been posted up in the office of the consul or other consular officer of the United States for ten days, in the port from which said vessel sailed ; and the certificate of such consul or consular officer over his official signature shall be competent evidence of such posting in any court of the United States. SEC. 4. That it shall be the duty of the Supervising Surgeon-Gen- eral of the Marine-Hospital Service, under the direction of the Secretary of the Treasury, to perform all the duties in respect to quarantine and quarantine regulations which are provided for by this act, and to obtain information of the sanitary condition of foreign ports and places from which contagious and infectious diseases are or may be imported into the United States ; and to this end the consular officer of the United States, at such ports and places as shall be designated by the Secretary of the Treasury, shall make to the Secretary of the Treasurj' weekly reports of the sanitary condition of the ports and places at which they are respect- ively stationed, according to such forms as the Secretary of the Treasury shall prescribe ; and the Secretary of the Treasury shall also obtain, through all sources accessible, including State and municipal sanitary authorities throughout the United States, weekly reports of the sanitiuy condition of ports and places within the United States, and shall pre- pare, publish, and transmit to collectors of customs and to State and QUARANTINE LAWS OF THE UNITED STATES. 537 municipal health officers and other sanitarians weekly abstracts of the consular sanitary reports and other pertinent information received by him ; and shall also, as far as he may be able, by means of the voluntary co-operation of State and municipal authorities, of public associations, and private persons, procure information relating to the climatic and other conditions affecting the public health, and shall make an annual report of his operations to Congress, with such recommendations as he may deem important to the public interests. SEC. 5. That the Secretary of the Treasury shall from time to time issue to the consular officers of the United States and to the medical officers serving at any foreign port, and otherwise make publicly known, the rules and regulations made by him, to be used and complied with by vessels in foreign ports, for securing the best sanitary condition of such vessels, their cargoes, passengers, and crew, before their departure for any port in the United States, and in the course of the voyage ; and all such other rules and regulations as shall be observed in the inspection of the same on the arrival thereof at any quarantine station at the port of destination, and for the disinfection and isolation of the same, and the treatment of cargo and persons on board, so as to prevent the introduc- tion of cholera, yellow fever, or other contagious or infectious diseases ; and it shall not be lawful for any vessel to enter said port to discharge its cargo or land its passengers, except upon a certificate of the health officer at such quarantine station certifying that said rules and regula- tions have in all respects been observed and complied with, as well on his part as on the part of the said vessel and its master, in respect to the same and to its cargo, passengers, and crew ; and the master of every such vessel shall produce and deliver to the collector of customs at said port of entry, together with the other papers of the vessel, the said bills of health required to be obtained at the port of departure and the cer- tificate herein required to be obtained from the health officer at the port of entry ; and that the bills of health herein prescribed shall be con- sidered as part of the ship's papers, and when duly certified to by the proper consular officer or other officer of the United States, over his official signature and seal, shall be accepted as -evidence of the statements therein contained in any court of the United States. SEC. 6. That on the arrival of an infected vessel at any port not provided with proper facilities for treatment of the same, the Secretary of the Treasury may remand said vessel, at its own expense, to the nearest national or other quarantine station, where accommodations and appliances are provided for the necessary disinfection and treatment of the vessel, passengers, and cargo ; and after treatment of any infected vessel at a national quarantine station, and after certificate shall have TEXT-BOOK OF HYGIENE. been given by the United States quarantine officer at said station that the vessel, cargo, and passengers are each and all free from infectious disease, or danger of conveying the same, said vessel shall be admitted to entry to any port of the United States named within the certificate. But at any ports where sufficient quarantine provision has been made by State or local authorities the Secretary of the Treasury may direct vessels bound for said ports to undergo quarantine at said State or local station. SEC. 7. That whenever it shall be shown to the satisfaction of the President that by reason of the existence of cholera or other infectious or contagious diseases in a foreign country there is serious danger of the introduction of the same into the United States, and that notwithstanding the quarantine defense this danger is so increased by the introduction of persons or property from such country that a suspension of the right to introduce the same is demanded in the interest of the public health, the President shall have power to prohibit, in whole or in part, the introduc- tion of persons and property from such countries or places as he shall designate and for such period of time as he may deem necessary. SEC. 8. That whenever the proper authorities of a State shall sur- render to the United States the use of the buildings and disinfecting apparatus at a State quarantine station, the Secretary of the Treasury shall be authorized to receive them and to pay a reasonable compensa- tion to the State for their use, if in his opinion they are necessary to the United States. SEC. 9. That the act entitled " An act to prevent the introduction of infectious or contagious diseases into the United States, and to es- tablish a national board of health," approved March 3, 1879, be, and the same is hereby, repealed. And the Secretary of the Treasury is directed to obtain possession of any property, furniture, books, paper or records belonging to the United States which are not in the posses- sion of an officer of the United States under the Treasur}^ Department which were formerly in the use of the National Board of Health or any officer or employe thereof. REVISED STATUTES. SEC. ^794. There shall be purchased or erected, under the orders of the President, suitable warehouses, with wharves and inclosures, where merchandise may be unladen and deposited, from any vessel which shall be subject to a quarantine or other restraint, pursuant to the health laws of any State, at such convenient places therein as the safety of the public revenue and the observance of such health laws may require. QUARANTINE LAWS OF THE UNITED STATES. 539 SEC. 4795. Whenever the cargo of a vessel is unladen at some other place than the port of entry or delivery under the foregoing provisions, all the articles of such cargo shall be deposited at the risk of the parties concerned therein, in such public or other warehouses or inclosures as the collector shall designate, there to remain under the joint custody of such collector and of the owner, or master, or other person having charge of such vessel, until the same are entirely unladen or discharged, and until the articles so deposited may be safely removed without contra- vening such health laws. And when such removal is allowed, the col- lector having charge of such articles may grant permits to the respective owners or consignees, their factors or agents, to receive all merchandise which has been entered, and the duties accruing upon which have been paid, upon the payment by them of a reasonable rate of storage ; which shall be fixed by the Secretary of the Treasury for all public warehouses and inclosures. SEC. 4796. The Secretary of the Treasury is authorized, whenever a conformity to such quarantines and health laws requires it, and in respect to vessels subject thereto, to prolong the terms limited for the entry of the same, and the report or entry of their cargoes, and to vary or dispense with any other regulations applicable to such reports or entries. No part of the cargo of any vessel shall, however, in any case, be taken out or unladen therefrom, otherwise than is allowed by law, or according to the regulations hereinafter established. SEC. 4797. Whenever, by the prevalence of any contagious or epi- demic disease in or near the place by law established as the port of entry for any collection district, it becomes dangerous or inconvenient for the officers of the revenue employed therein to continue the discharge of their respective offices at such port, the Secretary of the Treasury, or, in his absence, the First Comptroller, may direct the removal of the officers of the revenue from such port to any other more convenient place, within, or as near as may be to, such collection district. And at such place such officers may exercise the same powers, and shall be liable to the same duties, according to existing circumstances, as in the port or district established by law. Public notice of any such removal shall be given as soon as may be. [See Sec. 1776.] SEC. 4798. In case of the prevalence of a contagious or epidemic disease at the seat of government, the President may permit and direct the removal of any or all the public offices to such other place or places as he shall deem most safe and convenient for conducting the public business. [See Sec. 1776.] SEC. 4799. Whenever, in the opinion of the Chief Justice, or, in case of his death or inability, of the Senior Associate Justice of the 540 TEXT-BOOK OF HYGIENE. Supreme Court, a contagious or epidemic sicknets shall render it haz- ardous to hold the next stated session of the court at the seat of govern- ment, the Chief or such Associate Justice may issue his order to the Marshal of the Supreme Court, directing him to adjourn the next session of the court to such other place as such justice deems convenient. The marshal shall thereupon adjourn the court, by making publication thereof in one or more public papers printed at the seat of government from the time he shall receive such order until the time by law prescribed for commencing the session. The several circuit and district judges shall, respectively, under the same circumstances, have the same power, by the same means, to direct adjournments of the several circuit and district courts to some convenient place within their districts respectively. [See Sec. 1776.] SEC. 4800. The judge of any district court, within whose district any contagious or epidemic disease shall at any time prevail, so as, in his opinion, to endanger the lives of persons confined in the prison of such district, in pursuance of any law of the United States, may direct the marshal to cause the persons so confined to be removed to the next adjacent prison where such disease does not prevail, there to be confined until they may safely be removed back to the place of their first confine- ment. Such removals shall be at the expense of the United States. SEC. 4263. The master of any vessel employed in transporting pas- sengers between the United States and Europe is authorized to maintain good discipline and such habits of cleanliness among the passengers as will tend to the preservation and promotion of health ; and to that end he shall cause such regulations as he may adopt for this purpose to be posted up, before sailing, on board such vessel, in a place accessible to such passengers, and shall keep the same so posted up during the voyage. Such master shall cause the apartments occupied by such passengers to be kept at all times in a clean, healthy state; and the owners of every such vessel so employed are required to construct the decks and all parts of the apartments so that they can be thoroughly cleansed ; and also to provide a safe, convenient privy or water-closet for the exclusive use of every one hundred such passengers. The master shall also, when the weather is such that the passengers cannot be mustered on deck with their bedding, and at such other times as he may deem necessary, cause the deck occupied by such passengers to be cleansed with chloride of lime or some other equally efficient disinfecting agent. And for each neglect or violation of any of the provisions of this section the master and owner of any such vessel shall be severally liable to the United States in a penalty of fifty dollars, to be recovered in any circuit or district court within the jurisdiction of which such vessel may arrive QUARANTINE LAWS OF THE UNITED STATES. 541 or from which she is about to depart, or at any place where the owner or master may be found. [Extract from Act of August 1, 1888.] Whenever any .person shall trespass upon the grounds belonging to any quarantine reservation, . . . such person, trespassing, . shall, upon conviction thereof, pay a fine of not more than three hundred dollars, or be sentenced to imprisonment for a period of not more than thirty days, or shall be punished by both fine and imprisonment, at the discretion of the court. And it shall be the duty of the United States Attorney, in the district where the misdemeanor shall have been com- mitted, to take immediate cognizance of the offense, upon report made to him by any medical officer of the Marine-Hospital Service, or by any officer of the Customs Service, or by any State officer acting under authority of Section 5 of said act. [Act of March 27, 1890.] AN ACT to prevent the introduction of contagious diseases from one State to another and for the punishment of certain offenses. Be it enacted by the Senate and House of Representatives of the United States of America in Congress assembled, That whenever it shall be made to appear to the satisfaction of the President that cholera, yellow fever, small-pox, or plague exists in any State or Territory, or in the District of Columbia, and that there is danger of the spread of such disease into other States, Territories, or the District of Columbia, he is hereby authorized to cause the Secretary of the Treasury to promulgate such rules and regulations as in his judgment may be necessary to pre- vent the spread of such disease from one State or Territory into another, or from any State or Territory into the District of Columbia, or from the District of Columbia into any State or Territory, and to employ such inspectors and other persons as may be necessary to execute such regulations to prevent the spread of such disease. The said rules and regulations shall be prepared by the Supervising Surgeon-General of the Marine-Hospital Service, under the direction of the Secretary of the Treasury. And any person who shall willfully violate any rule or regu- lation so made and promulgated shall be deemed guilty of a misde- meanor, and upon conviction shall be punished by a fine of not more than five hundred dollars, or imprisonment for not more than two years, or both, in the discretion of the court. SEC. 2. That any officer, or person acting as an officer, or agent of the United States at any quarantine station, or other person employed to aid in preventing the spread of such disease, who shall willfully violate any of the quarantine laws of the United States, or any of the 542 TEXT-BOOK OF HYGIENE. rules and regulations made and promulgated by the Secretary of the Treasury as provided for in Section 1 of this act, or any lawful order of his superior officer or officers, shall be deemed guilty of a misdemeanor, and upon conviction shall be punished by a fine of not more than three hundred dollars, or imprisonment for not more than one year, or both, in the discretion of the court. SEC. 3. That when any common carrier or officer, agent, or employe* of any common carrier shall willfully violate any of the quarantine laws of the United States, or the rules and regulations made and promul- gated as provided for in Section 1 of this act, such common carrier, officer, agent, or employe shall be deemed guilty of a misdemeanor, and shall, on conviction, be punished by a fine of. not more than five hun- dred dollars, or imprisonment for not more than two years, or both, in the discretion of the court. QUESTIONS TO CHAPTER XXIII. QUARANTINE. What is meant by quarantine? From what is the term derived? Has it now any definite limitation as to time? To what is the term applied ? What are the two natural divisions of quarantine ? What are the principal quarantinable diseases ? What determines the length of quarantine for each of these? Should tuberculosis be quarantinable? What is meant by foreign quarantine? What regulations are now to be observed at foreign ports by vessels clearing for the United States? What officers have charge of this foreign quarantine? What are some of the points considered in the bill of health? What are some of the requirements with regard to vessels and their cargoes ? Regarding passengers and crew ? What are the objects of the inspection card given to passengers ? What requirements are to be observed at sea? What method is prescribed for the disinfection of vessels? Of cargoes? What can be said of the efficiency of the foregoing regulations ? What is meant by domestic quarantine? What will govern the equipment of a maritime quarantine station? What are required at a fully-equipped station ? What is the method of construction of the most recent steam disinfecting chambers, and in what ways are they superior to the earlier models ? What precautions are to be observed in operating them ? What is the principle of construction of the sulphur-furnaces now used at quarantine stations, and wherein are they superior to other methods of producing sulphurous-acid gas? How is the gas to be con- veyed into the holds of vessels, etc. ? What apparatus is provided for using germicidal solutions? Where barracks are necessary, how should they be arranged and equipped ? What facilities for bathing should be provided ? What is to be said of the water-supply ? What regulations are to be observed at ports of entry and on the frontier ? What points are covered by the inspection, and what vessels are exempt from inspection? What vessels are to be quarantined, and for how long? What are the general requirements at quarantine? What treatment must cholera-infected vessels undergo in quarantine? What is the prescribed method of disinfection ? What routine is to be observed with passengers detained on account of cholera ? (543) 544 QUESTIONS TO CHAPTER XXIII. How are the personal effects of passengers and crew and the cargo to be disinfected ? Under what conditions may traffic be allowed from ports infected with yellow fever? What inspection is required of State and local quarantines? What regulations govern the Canadian and Mexican frontiers ? What are some of the points to be observed in the successful management of a quarantine station ? What are some of the special points in the disinfection of wooden vessels for yellow fever ? Is there any evidence that ballast may convey infection ? What is meant by " dipped ballast"? How are the holds of wooden vessels to be disinfected? What other treatment of yellow-fever vessels may be suggested ? What is the treatment required for cholera-infected vessels ? What special measures are to be taken against cholera? Who has supreme command of a cholera camp, and how is it to be divided? What are the regulations to be observed in the detention camp? In the hospital camp ? Why should infected dejecta and ejecta be disinfected immedi- ately upon discharge? How many national quarantine stations are there, and where are they located? Give a brief description of those in the Delaware Bay and River. What government vessel is used as a quarantine station ? What are some of the aids to national quarantine ? What inspection is required of all quarantines ? What is required of all State and local quarantines ? What are the instructions, both general and special, to the officers detailed to inspect State and local quarantines? What is meant by inland quarantine? By the sanitary cordon? When and where has the latter been employed in the United States, and with what success ? What is a camp of probation ? What is the differ- ence between it and a camp of refuge ? How should a camp of probation be equipped, managed, and guarded ? What should be the daily routine of such a camp ? What regulations should be promulgated and enforced for such a camp ? Have these camps been efficacious in preventing the spread of disease ? What is the purpose of railroad quarantine, and how is it to be carried out? How may it be facilitated by train-inspection service? What rules are to be adopted for railway quarantine ? What action has been taken to prevent the introduction of small-pox, etc., from Canada? What are the regulations issued for the guidance of sanitary inspectors? What provisions are there for the medical inspection of immigrants on board trains? What general principles govern interstate quarantine? What are the regulations covering it ? Which of these is the most important ? QUESTIONS TO CHAPTER XXIII. 545 What special provisions are made respecting yellow fever? What are the methods of disinfection prescribed, respectively, for cholera, yellow fever, small-pox, and typhus fever? What are the essential points of municipal quarantine? What pre- cautions are to be taken to prevent the spread of small-pox, measles, diphtheria, and scarlet fever ? To what extent should domiciliary quar- antine be carried ? How long should it be maintained ? How may a diagnosis of diphtheria be made? What means may be taken to prevent the spread of tuberculosis? Give a synopsis of the quarantine laws of the United States. What is the maximum penalty for attempting to enter a port in evasion of them? What information of value to quarantine officers, etc., is furnished weekly? When and by whom may travel and traffic from infected ports and places be prohibited? Who has supreme charge of the enforcement of the quarantine regulations ? In what department of the government does the supervision of quarantine belong ? 35 INDEX. Absolute and relative humidity, 6 Actinoinycosis, 376 Adjustable school-desk, 211 Adulterations in milk, 97 of flour, 113 "A. G. M." water-closet, 184 Aids to quarantine, 497 Air, 1 currents and their influence upon health, 18 examination of, 413 tests for impurities in, 415 Alcohol poisoning, 118 Alcoholic beverages, 117 Alimentary beverages, 117 Alkaloidal beverages, 123 Alum, as a purifier of muddy water, 63 in bread, 437 Ammonia in water, 78 test for, 427 Angus Smith's experiments on carbon dioxide and organic matter, 27 modification of, 419 Aniline poisoning, 236 Animal diseases and ground-water, 142 Annatto in milk, test for, 433 Anthrax, 378 Antiseptics and antisepsis, 387 Arsenie, in wall-papers, 177 poisoning, 241 Ash in flour, 436 in milk, test for, 433 Asiatic cholera, 347 Atmosphere, composition and physical conditions of, 2 its influence upon health, 1 its limit upward, 3 Atmospheric pressure and health, 8 Bacillus anthracis as a cause of diseased meat, 109 Bacillus of anthrax, 378 of glanders, 378 of typhoid fever, 57, 67, 362 tuberculosis, 532 Bacteria in the atmosphere, 32 Bacteriological examination of drinking- water, 81, 430 Baker, H. B., on effects of low tempera- ture on health, 15 Barometric pressure, 3 Barracks, 252, 464 Bathing, dangers of cold, 296 rules for, 295 Baths, and bathing, 293, 465 public, 299 Beer, 122 Berlier's system, 156 Bert's observations on diminished at- mospheric pressure, 10 Beverages, alimentary, 117 alkaloidal, 123 containing alcohol, 117 Birth rate, 406 Births, registration of, 404 Black death, 326 hole of Calcutta, 28 Boccaccio on the plague, 326 Bora, 19 Boric acid in milk, tests for, 434 Boudin on malarial fever from drinking- water, 64 Bovine tuberculosis, 377 Bowditch, H. L, on soil moisture and consumption, 141 Brandy, 120 "Brass-founders' ague," 235 Bread, 112 component parts of, 436 Broad Street pump epidemic of cholera, 68 Bromine poisoning, 232 Buchanan, Dr. G., on earth-closets, 154 on soil moisture and consumption, 142 Building material, 172 Burial-grounds, supposed dangers of, 308 Bury ventilator, 175 Butter, 101 as food, 434 component parts of, 434 Cabiadis on the plague in Bagdad, 329 Cable, G. W., on convict-lease system, 281 Caisson disease, 12 Camp, detention, 492 diseases, 254 hospital, 493 Perry, 506 Waynesville detention, 509 Camps, civilian, 258 of probation, 505 Carbon-bisulphide poisoning, 231 Carbon dioxide in atmosphere, 2, 26 poisoning, 230 Carbon monoxide, in air, 29 poisoning, 229 (547) 548 INDEX. Caterham epidemic of typhoid fever, 65 Census, the, 401 Cerebro-spiual meningitis, 372 Chamber-land's filter, 73 Chambers, J. W., on pollution of hy- drant-water, 70 Chantemesse and Vidal on the bacillus typhoideus in drinking-water, 67 Cheese, 102 Chemical composition of ground-air, 133 Chlorides in water, 76 Chlorine-gas poisoning, 228 Chlorine in water, tests for, 424 Chocolate, 124 "Choke-damp," 230 Cholera, 14, 68 and drinking-water, 354 and ground-water, 140 Asiatica, 347, 520, 524 bacillus, 352 camp, regulations for, 491 causation of, 353 from infected water, 68 prevention of, 356 special quarantine measures against. 488 vessels, treatment of, 486 Cider, 121 Cisterns as storage reservoirs, 51 Civilian camps, 258 Classification of drinking-waters, 82 Clothing, absorption of heat by, 301 how to render non-inflammable, 304 materials, 301 of the soldier, 251 Coal-gas, 30 Coffee, 123 Condiments, 114 Connolly trap, 190 Consumption, among school-children, 218 and soil moisture, 141 prevention of, 533 Contagion and infection, 319 Contagious diseases and schools, 218 Contagium animatum, 313 Contamination of hydrant-water, 70 Cooking, methods of, 115 Cowles, Dr. E., experiments on heating hospitals, 200 Creamometer, 100 Cremation, 162, 310 of sewage and garbage, 162 Crematory at quarantine stations, 465 Cucumber odor in drinking-water, 56 Cultivation of bacteria, 316 Cultures in suspected diphtheria, 532 Cysticercus in meat, 106 Da Costa, Dr. J. M., on irritable heart, 288 Daily allowance of water in American cities, 50 Dead, disposal of, 307 Death-rate and birth-rate 406 Deaths, registration of, 405 Decayed meat and fish as causes of dis- ease, 106 "Dececo" closet, 185 DeChaumont's rule regarding ground- water oscillations, 140 Defective hearing among school-chil- dren, 216 Defoe on the plague, 327 Delabarre, F. A., on physical develop- ment, 288 Dengue, 369 Deodorizers, 388 Diarrhoea and dysentery in armies, 254 Diarrhoeal diseases, 14 Dickson on the plague in India, 329 Digestive derangements among school- children, 217 Diphtheria, 322, 368, 529 diagnosis of, 531 Diseases caused by high temperature, 14 from impure water, 62 from infected and spoiled meat, 105 from infected milk, 98 from soil impurities, 139 of animals communicable to man, 376 of school-children, 213 on shipboard, 271 registration of, 405 Disinfectants and disinfection, 387 Disinfection, methods of, 393 by germicidal solutions, 463 for cholera, 524 for small -pox, 525 for typhus fever, 526 for yellow fever, 525 of wooden vessels, 479 Distilled water, 58 Domestic quarantine, 458 Domiciliary quarantine, 527 Drainage of wet soils, 143 Drinking-water, examination of, 81 sources of, 51 standards of purity of, 59 Drowned persons, restoration of, 296 Duration of infection, 321 Dwellings, and overcrowding, 165 heating and ventilation of, 174 materials of which to be built, 172 Dysentery, 14 Earth-closets, 153 Eberth's bacillus as a cause of typhoid fever, 67 Eggs as food, 111 Elephantiasis, 14 Electric light and its dangers, 179 INDEX. 549 Emigrant ships, sanitary and medical service on board, 273 Emmerich on the innocuousness of im- pure water, 65 Entombment, 309 Epidemic diseases, 320, 372 due to defective ventilation, 29* history of, 325 Erismann on Liernur's system, 155 Examination of air, water, and food, 413 Exercise and training, 285 physiological effects of, 285 Fats in milk, test for, 433 Fever, malarial, 14, 63, 64, 255 mountain, 53 relapsing, 360 scarlet, 99, 322, 367, 529 splenic, 314 typhoid, 65, 67, 141, 256, 322, 361, 409 typhus, 256, 363, 526 yellow, 14, 135, 364, 485, 503, 509, 512, 523, 525 Filtration of water, 73 "Fire-clamp," 30, 230 Flour and bread, 436 component parts of, 436 tests for impurities in, 437 Flushing cistern for water-closets, 187 Fodor on the production of carbon di- oxide, 27 Fohn, 19 Folsom, C. F., "on typhoid fever from infected water, 67 Food, examination of, 431 necessary to health, 87 of the soldier, 250 Foods, classification, of, 95 cooking of, 115 of animal origin, 95 of vegetable origin, 112 Foreign quarantine, 443 Forwood, Dr. W. S., on hydrochloric- acid fumes, 228 Freire on yellow-fever genii in soil, 135 Fresh-air inlet, 191 Fruits and nuts, 114 Gardner, James T., on Rochdale sys- tem, 151 Gas poisoning, 29 Germ theory, 313 Germicidal solutions, disinfection by, 463 Gihon, Dr. A. L., on naval hygiene, 261 on syphilis in the United States, 342 Gin, 121 Glanders, 378 Green vegetables, 114 Ground-air, 132 Ground-water, 137 and cholera, 140 and typhoid fever, 141 Habitations, 165 Habits of the sailor, 261 Haemic diseases, 14 Hammond's experiment on organic mat- ter in the air, 28 Hardness of water, 60 tests for, 428 Harmattan, 19 Heart disease and altitude, 11 Heating and ventilation of dwellings, 174 Hecker on the plague, 326 Hold, ship's, disinfection of, 483 Hopper-closets, 182 Hospital, administration and manage- ment, 203 records, 205 Hospitals, construction of, 195, 463 management of, 203 ventilation and heating of, 199 House, building material of, 172 interior arrangements of, 174 sanitary arrangements, supervision of, 191 water-supply of, 180 House-drainage, 180 Howard, John, on hospital construction, 199 Humidity, and health, 18 of the atmosphere, 5 Hydrophobia, 377 Hygiene, industrial, 223 marine, 261 military and camp, 249 prison, 279 school, 207 Illuminating gas, dangers of, 178 Impurities in water, 59 signification of, 80 tests for, 74 Increased atmospheric pressure, 12 Incubation of infectious diseases, table of, 321 report of, to the London Clinical Society, 321 Industrial hygiene, 223 Infants, mortality among, 408 Influence of barometric pressure upon results of operations, 12 Influenza, 15, 322, 371 Ingrafting, 335 Inland quarantine, 501 Inoculation of small-pox, 335 Interment, 307 in war, 310 Interstate quarantine, 521 regulations governing, 522 Iodine poisoning, 232 Jenner, Edward, and vaccination, 338 Jesty, Benjamin, 338 550 INDEX. Johns Hopkins Hospital, 196 Jones, Dr. Joseph, on syphilis among the mound-builders, 374 Kefyr, 122 Kober, G. M., on mountain fever, 53 Koch, R., on the cholera spirillum in drinking-water, 69 Kumys, 122 Lactometer, 100 Lactoscope, 100 Lakes and ponds as sources of drinking- water, 55 Lambrecht's poly meter, 8 Latrines, 465 Lead poisoning, 233 Legumes, 113 Liernur's pneumatic system, 155 Lighting of dwellings, 177 Lortet's observations on diminished at- mospheric pressure, 8 Low temperature as a cause of respira- tory diseases, 15 Malarial fevers, 14 in armies, 255 Marine hygiene, 261 Maritime quarantine, 458 administration of, 466 Marriages, registration of, 404 Marsh-water and malaria, 63 Marshall, John, on cholera from infected water, 68 Mate", 125 McClellan's trap, 188 McSherry, R., on siguatera, 108 Measles, 322, 367, 529 Meat, 103 extracts and essences, 105 Mercurial poisoning, 234 Metabolism during muscular exercise, 94 Methods of cooking, 115 of sewage removal, 148 Michigan method of restoring the ap- parently drowned, 297 Midden privies, 150 Military and camp hygiene, 249 Milk, as food, 95, 431 adulteration of, 432 component parts of, 432 sickness, 100 tyrotoxicon in, 101 Mineral poisons in water, 79 tests for, 429 Mistral, 18 Montagu, Lady M. W., on inoculation, 335 Montgomery quarantine conference, 515 Moore, J. W., on seasonal prevalence of pneumonia, 17 Morin, on fresh air required in occupied apartments, 40 Mortality among infants, 408 in prisons, 281 Motion of the atmosphere, 7 Mountain fever, 53 sickness, 10 Municipal quarantine, 526 Mumps, 322 Myopia of school-children, 213 National quarantines, 494 aids to, 497 stations, regulations for, 466 Naval hygiene, 261 rations, 268 Neirnsee, J. R., on ventilating hospital wards, 200 Nervous disorders among school -chil- dren, 217 Nichols, A. H., on pollution of drinking- water, 56 Nitrates and nitrites in water, 77 tests for, 425, 426 Norther, 19 Occupation neuroses, 245 Occupations, hygiene of, 223 Oleo-margariue, 102, 434 Organic matter in water, 75 Organisms in small-pox, 334 Oriental plague, 325 Over Darwen epidemic of drinking- water, 66 Overexertion, 288 Oxygen and CO 2 in ground-air, 134 Oxygen in atmospheric air, 3 Ozone in the atmosphere, 7 Pan- closets, 181 Passengers on shipboard, 264 protection of, 273 report on, to American Public Health Association, 274 Pathogenic organisms in ground-air, 134 Pavilion hospitals, 18 Pebrine, 314 Pengra, C. P., on bacteria in drinking- water, 57 Pepper, William, on consumption and soil moisture, 142 Perlsucht, 377 Peroxide of hydrogen in the atmos- phere, 7 Petroleum vapor as a poison, 233 Pettenkofer, on carbon dioxide in air, 420 on ground-air, 133 on ground-water and cholera, 355 Phosphates in water, tests for, 430 Phosphorus necrosis, 242 Phthisis in armies, 256 INDEX. 551 Physical development, table on, 289 training, 286 Physiological action of alcohol, 117 Plague, 325 Plunger-closets, 182 Plymouth epidemic of typhoid fever, 67 Pneumonia and cold weather, 16 Poisonous dust, 237 gases and vapors, 227 Power, W. H., on scarlet fever from milk, 99 Preventive inoculation, 315 Prison hygiene, 279 punishments, 282 Privies, deodorization of contents of, 149 removal of contents of, 149 ventilation of, 149 Privy-vaults, construction of, 148 pits, 150 system, 148 wells, 150 Procopius on the plague, 325 Prudden on typhoid bacilli in drinking- water, 57 Ptomaines in meat, 107 Public baths, 299 Purification of drinking-water, 72 Purulent conjunctivitis, 256 Quarantinable diseases, 442 Quarantine, 441 aids, 497 conference at Montgomery, 515 contrivances, 459 danger from flies in, 494 domestic 458 domiciliary, 527 foreign, 443 regulations, efficiency of, 456 inland, 501 interstate, 521 laws of United States, 534 municipal, 526 , plant, 459 railroad, 512 regulations governing, 466 to be observed at foreign ports and at sea, 443 service, national, 494 stations, management of, 477 maritime, 458 on Delaware Bay and River, 495 Quarantines, national inspection of all, 498 instructions for inspecting officers, 499 Questions to chapter i, 45-48 to chapter ii, 84-86 to chapter iii, 126-129 to chapter iv, 145, 146 to chapter v, 163, 164 to chapter vi, 193, 194 Questions to chapter vii, 206 to chapter viii, 220, 221 to chapter ix, 247, 248 to chapter x, 260 to chapter xi, 278 to chapter xii, 284 to chapter xiii, 291 to chapter xiv, 300 to chapter xv, 305 to chapter xvi, 312 to chapter xvii, 317 to chapter xviii, 323 to chapter xix, 380-385 to chapter xx, 399, 400 to chapter xxi, 411, 412 to chapter xxii, 439, 440 to chapter xxiii, 543-545 Rabies, 377 Rag-sorters' disease, 240 Railroad inspection against small -pox, 516 against yellow fever, 514 medical inspection of immigrants against cholera, 520 quarantine, 512 Rain-water, 52 Registration of births, 404 of deaths, 405 of diseases, 405 of marriages, 404 Relapsing fever, 360 Rennie on the plague, 329 Restoration of apparently drowned per- sons, 296 River-water, 52 Rochdale system, 151 Roy, A., on carbon -dioxide poisoning, 230 Rubeola, 322 Rum, 121 Sailor-life, 261 Sanitary cordon, 501 Sausage poisoning, 107 Scarlet fever, 322, 367, 529 from milk, 99 Schlagintweit's observations on mount- ain sickness, 9 Schone system, 156 School-furniture, 210 -house construction, 207 -hy*giene, 207 -life, diseases of, 213 Scurvy in armies, 256 Sea-bathing, 294 Season and mortality from various dis- eases, 20 Seaton and Buchanan on protective power of vaccination, 341 Self- purification of flowing water, 54 Separate system, 156 552 INDEX. Sewage, and sewerage, 147 farms, 161 final disposal of, 161 irrigation at Pullman, 161 removal, methods of, 148 Sewer- air, 30 Sheep pock, 376 Ship sanitation, 264 Siegfried, Surg. C. A., on naval rations, 271 Simoon, 19 Sirocco, 19 Site for dwellings, 167 Small-pox, 331, 516, 525 limiting the spread of, conference in Chicago, 346 Smart, C., on mountain fever, 53 on pollution of cistern-water, 51 Soap test for hardness in water, 60 Soil, atmosphere of, 132 character of, for building sites, 168 drainage, 143 its physical and chemical characters, 131 moisture and health, 167 pipe, 189 water of the, 137 Solids in water, 75 of milk, tests for, 433 Sources of drinking-water, 51 Spinal curvature in school-children, 217 Spirillum of relapsing fever, 361 Splenic fever, 314 Spongilla fluviatilis, 56 Spring-water, 57 Standards of purity of drinking-water, 59 Statistics, vital, 401 Steam disinfecting chambers, 460 Sternberg, Gr. M., on destruction of pathogenic germs by boiling water, 72 on yellow-fever germs of Freire, 135, 365 Storage of water, 51, 71 Study-hours for pupils, 212 Suicide and season, 26 Sulphur-furnace, 462 Sun-stroke and humidity, 13 Supervision of sanitary arrangements, 191 Sweating sickness, 330 Swell-head, 376 Swill-milk, 99 Syphilis, 373 Table of constituents of animal foods, 90 of constituents of vegetable foods, 91 Tea, 124 Temperature and health, 13 of the air, 5 Temperature of fire -rooms of ships, 268 Tents and huts, 253 Tests for atmospheric impurities, 33, 415 for impurities in drinking-water, 74, 423 in food, 431 Texan northers, 19 Thome on typhoid fever from drinking- water, 65 Tobacco, 125 Toilet's system of barracks, 252 Tracy, Dr. R. S., on infecundity of tobacco-workers, 239 Training, physical, 286 Traps, 187 Trembles, the, 100 Trichina spiralis in meat, 105 Tuberculosis, 532 Tuberculous meat, 110 Turpentine vapor, effects of, 232 Typhoid fever, 361, 322 and ground-water, 141 causation of, 362 from drinking-water, 65 in armies, 256 Typhus fever, 363 in armies, 256 Tyrotoxicon in milk, 101 Vaccination, 337 and syphilis, 343 mode of performing the operation, 341 Valve-closets, 182 Vaughan, V. C., on the bacillus ty- phoideus in drinking-water, 68 on poisonous cheese, 103 on tyrotoxicon as a cause of cholera infantum, 101 Vaughan's daily ration, 89 Vegetables, green, 114 Venereal diseases in armies, 257 Ventilation, 38 and heating of hospitals, 199 of prisons, 282 of ships, 266 Vessels, cholera, treatment of, 486 wooden, disinfection of, 479 yellow-fever, treatment of, 485 Vital statistics, 401 Voit's standard diet-tables, 89 Warms; system at Memphis, 157 examination of, 423 Water, 49 hardness, of, 60 tests for, 428 impurities in, 59 diseases due to, 62 required by human beings, 49 storage and purification of, 71 INDEX. 553 Water-supply, at quarantine stations, 465 in dwellings, 180 tests for impurities in, 74, 423 Water-carriage system of sewage re- moval, 156 Water-closets, 181 Well-water, 57 Whisky, 120 Wines, 121 Wolpert's air-tester, 34 Wolpert's air-tester, modification of, 418 Wool-sorters' disease, 240 Wy man's cuse-record, 205 Yellow fever, 14, 364 causation of, 14, 365 cordon in Texas, 503 epidemic in Brunswick, Ga., 509 in Florida, 512 vessels, treatment of, 485 J >* \\ o* t ^>r. ' > r*- ""'' 913 WA100 R737t Rone, George H Text-book of hygiene . WA100 3737t , George H Text-tc ,giene ... MEDICAL SCIENCES LIBRARY UNIVERSITY OF CALIFORNIA, IRVINE IRVINE, CALIFORNIA 92664